The document discusses the influence of intensive physical training on growth and pubertal development in athletes. It finds that while moderate physical activity is beneficial, excessive training can negatively impact growth, especially in gymnastics where energy availability is restricted. In artistic gymnasts, growth potential is attenuated, more so in males. However, in female rhythmic gymnasts genetic predisposition to growth is preserved due to late catch-up growth. Intensive training and negative energy balance also delay puberty in various sports by prolonging the prepubertal stage and shifting pubertal development to a later age based on bone maturation rather than chronological age.
Tamara Valovich McLeod, Ph.D. - "The Impact of Sport-Related Injury on Health...youth_nex
The Youth-Nex Conference on Physical Health and Well-Being for Youth, Oct 10 & 11, 2013, University of Virginia
Tamara Valovich McLeod, Ph.D. - "The Impact of Sport-Related Injury on Health-Related Quality of Life"
Valovich McLeod is the John P. Wood, D.O., Endowed Chair for Sports Medicine and a Professor in the Athletic Training Program at A.T. Still University.
Panel 5 -- Injury Prevention and Treatment. While being physically active is important for positive youth development, injuries can result. This panel will discuss ways to minimize injury, particularly concussions, while addressing the impact of sport-related injury on quality of life. The panel will also provide a blueprint for encouraging life-long physical activity.
Website: http://bit.ly/YNCONF13
Russell Pate, Ph.D. - "Health Effects of Physical Activity in Children and Yo...youth_nex
This document summarizes the evidence on the health effects of physical activity in children and youth. It outlines current physical activity guidelines for children and discusses limitations in the scientific evidence. Specifically, it notes that there is little evidence on the effects of physical activity in children under age 6. Additionally, the influences of physical activity on weight status and the dose-response relationships for most health outcomes are poorly understood. The document also reviews limitations such as a lack of prospective longitudinal studies and large-scale clinical trials.
This study examined differences in physical fitness and physical activity self-efficacy among 1,432 4th grade students from urban and suburban schools. It found that minority and low-socioeconomic status (SES) children scored lower than white and higher-SES peers on fitness tests and a self-efficacy scale. Among girls and boys, significant effects were seen for ethnicity and SES. Post-hoc analysis revealed minority and low-SES students scored lower on mile run, curl-ups, push-ups, BMI, and self-efficacy. The study aims to use these findings to develop school-based interventions to improve physical fitness and health among underserved minority youth.
Charles Hillman, Ph.D. - "The Relation of Childhood Fitness and Adiposity to ...youth_nex
The document discusses the relationship between childhood fitness, obesity, and cognitive and brain health. It summarizes research showing that higher fitness is associated with better performance on achievement tests and cognitive tasks involving inhibition, working memory, and cognitive flexibility. Studies find higher fit children have larger basal ganglia volumes and better relational memory. An intervention study found an after-school physical activity program improved cognitive control as measured by ERPs. Higher adiposity is linked to poorer cognitive performance and brain health. Acute exercise benefits cognitive performance. Collectively, the findings suggest physical activity benefits academic performance and cognitive development by supporting brain health.
The study surveyed 198 Greek students aged 15-17 years on their physical activity levels using the stages of change model. The majority (63%) were physically active in stages 4 or 5, with 53% in stage 5 having maintained an active lifestyle for over 6 months. Boys showed higher activity levels than girls at 75% versus 54%. Younger students (1st grade) had higher activity levels than older students (78% versus 50% for 3rd grade). Thus, inactivity seemed more pronounced among girls and older students. The researchers concluded that physical activity programs and services should emphasize girls and older students more prone to inactivity.
1) The physical health of college students is influenced by their exercise habits, nutrition, sleep, and stress management. However, less than half of students meet the recommended 30 minutes of exercise per day.
2) Physical activity provides mental health benefits like reduced depression and anxiety. It also positively impacts academic performance.
3) Male students are more motivated by intrinsic factors like strength and enjoyment, while females are more influenced by extrinsic factors like weight management and appearance due to societal pressures. Long-term exercise motivation requires intrinsic enjoyment of physical activity.
Physical Activity in Australian Adults: A Public Health PerspectiveLouise Miller Frost
Physical inactivity poses health risks for the majority of Australian adults and is a modifiable risk factor for diseases like cardiovascular disease and diabetes. While guidelines recommend at least 150 minutes of moderate physical activity per week, surveys found about 40% of Australians do not meet this level. Individual education interventions have shown only moderate short-term effectiveness in increasing physical activity levels. Environmental interventions also have limited effectiveness, and population physical activity levels remain largely unchanged. Intersectoral actions across multiple areas may be needed to more successfully promote physical activity.
Tamara Valovich McLeod, Ph.D. - "The Impact of Sport-Related Injury on Health...youth_nex
The Youth-Nex Conference on Physical Health and Well-Being for Youth, Oct 10 & 11, 2013, University of Virginia
Tamara Valovich McLeod, Ph.D. - "The Impact of Sport-Related Injury on Health-Related Quality of Life"
Valovich McLeod is the John P. Wood, D.O., Endowed Chair for Sports Medicine and a Professor in the Athletic Training Program at A.T. Still University.
Panel 5 -- Injury Prevention and Treatment. While being physically active is important for positive youth development, injuries can result. This panel will discuss ways to minimize injury, particularly concussions, while addressing the impact of sport-related injury on quality of life. The panel will also provide a blueprint for encouraging life-long physical activity.
Website: http://bit.ly/YNCONF13
Russell Pate, Ph.D. - "Health Effects of Physical Activity in Children and Yo...youth_nex
This document summarizes the evidence on the health effects of physical activity in children and youth. It outlines current physical activity guidelines for children and discusses limitations in the scientific evidence. Specifically, it notes that there is little evidence on the effects of physical activity in children under age 6. Additionally, the influences of physical activity on weight status and the dose-response relationships for most health outcomes are poorly understood. The document also reviews limitations such as a lack of prospective longitudinal studies and large-scale clinical trials.
This study examined differences in physical fitness and physical activity self-efficacy among 1,432 4th grade students from urban and suburban schools. It found that minority and low-socioeconomic status (SES) children scored lower than white and higher-SES peers on fitness tests and a self-efficacy scale. Among girls and boys, significant effects were seen for ethnicity and SES. Post-hoc analysis revealed minority and low-SES students scored lower on mile run, curl-ups, push-ups, BMI, and self-efficacy. The study aims to use these findings to develop school-based interventions to improve physical fitness and health among underserved minority youth.
Charles Hillman, Ph.D. - "The Relation of Childhood Fitness and Adiposity to ...youth_nex
The document discusses the relationship between childhood fitness, obesity, and cognitive and brain health. It summarizes research showing that higher fitness is associated with better performance on achievement tests and cognitive tasks involving inhibition, working memory, and cognitive flexibility. Studies find higher fit children have larger basal ganglia volumes and better relational memory. An intervention study found an after-school physical activity program improved cognitive control as measured by ERPs. Higher adiposity is linked to poorer cognitive performance and brain health. Acute exercise benefits cognitive performance. Collectively, the findings suggest physical activity benefits academic performance and cognitive development by supporting brain health.
The study surveyed 198 Greek students aged 15-17 years on their physical activity levels using the stages of change model. The majority (63%) were physically active in stages 4 or 5, with 53% in stage 5 having maintained an active lifestyle for over 6 months. Boys showed higher activity levels than girls at 75% versus 54%. Younger students (1st grade) had higher activity levels than older students (78% versus 50% for 3rd grade). Thus, inactivity seemed more pronounced among girls and older students. The researchers concluded that physical activity programs and services should emphasize girls and older students more prone to inactivity.
1) The physical health of college students is influenced by their exercise habits, nutrition, sleep, and stress management. However, less than half of students meet the recommended 30 minutes of exercise per day.
2) Physical activity provides mental health benefits like reduced depression and anxiety. It also positively impacts academic performance.
3) Male students are more motivated by intrinsic factors like strength and enjoyment, while females are more influenced by extrinsic factors like weight management and appearance due to societal pressures. Long-term exercise motivation requires intrinsic enjoyment of physical activity.
Physical Activity in Australian Adults: A Public Health PerspectiveLouise Miller Frost
Physical inactivity poses health risks for the majority of Australian adults and is a modifiable risk factor for diseases like cardiovascular disease and diabetes. While guidelines recommend at least 150 minutes of moderate physical activity per week, surveys found about 40% of Australians do not meet this level. Individual education interventions have shown only moderate short-term effectiveness in increasing physical activity levels. Environmental interventions also have limited effectiveness, and population physical activity levels remain largely unchanged. Intersectoral actions across multiple areas may be needed to more successfully promote physical activity.
A Practical Measure of Balance, Gait, and Muscular Power in Older Adults: The...Kyle Menkosky
This document describes the Short Physical Performance Battery (SPPB), which is a validated test used to assess physical function in older adults. The SPPB examines balance, gait, and lower body strength through tests of standing balance, walking speed, and repeated chair stands. It provides an overall score of 0-12 based on performance in each test. Studies have shown SPPB scores predict disability, nursing home admission, and mortality in older adults. The document argues the SPPB is a practical test that can be used in cardiac and pulmonary rehabilitation to safely identify frailty and guide exercise interventions to improve outcomes in older patients.
This document outlines a study on factors associated with physical inactivity among first year undergraduate students at Universiti Putra Malaysia. It includes a literature review on previous research examining relationships between physical inactivity and socio-demographic factors, environmental support, mental health, self-efficacy, and body image. The document presents the study objectives, conceptual framework, and methodology, which will involve a cross-sectional study using cluster sampling of first year undergraduates to examine associations between physical inactivity and various independent variables.
Cognitive Benefits of Exercise for Children and TeensMark Dreher PhD
The brain evolves during our childhood years as it continues to develop and is affected by lifestyle habits such as physical activity, cognitive activity, nutrition and sleep.
Although there is growing scientific evidence that exercise is associated with improved cognitive function, academic performance, and overall health in children, the limited amount of time generally dedicated to physical activity during the school day continues to decline in many schools.
The activity requirements for healthy brain and cognitive function are really relatively modest. For children, moderate aerobic activity of about 60 minutes a day can make a big difference, especially in children that are currently low-performers. There is work to be done in the United States and other countries to meet these activity goals as only about 30% of high school students achieve them.
This presentation provides a current summary of the human research on aerobic exercise and cognitive function in children and teens.
Mark Dreher PhD
This study examined the relationship between various modes of physical activity (PA) and academic achievement in adolescents. It found that:
1) Males engaged in higher levels of PA than females across most modes measured, including habitual PA, active transport, physical education, extra-curricular sport, and community-based sport.
2) For males, habitual PA and physical education minutes were positively correlated with academic achievement. For females, only physical education minutes were positively correlated.
3) Physical education minutes emerged as the strongest predictor of academic achievement for both males and females in regression analysis.
The study concluded that physical education should be adequately included in the school curriculum due to its associations with academic achievement. It also noted
A Comprehensive Mixed-Longitudinal Study of Growth in Boys with Autism Spectr...Cherie Green
The first aim in the current study was to replicate previous findings indicating a phase of early overgrowth of HC, height and weight. The second aim was to investigate if growth dysregulation was also apparent in older children and adolescents with ASD. If a general growth dysregulation was found in boys with ASD from birth - 16 years of age, it was hypothesized that this growth dysregulation may be the result of either 1) connective tissue abnormalities, and/or
2) dysregulation of the HPA axis. A further exploratory aim was to identify biologically distinct subgroups within ASD based on specific growth, behavioural, and biological patterns.
The results from both Study 1 and 2 confirmed that an overall growth dysregulation exists in ASD. Boys with ASD are smaller at birth, but then grow at a faster rate, so that by 4 years of age they are larger than TD boys. They then stay larger throughout childhood and adolescence. Although there were no group differences in the overall rate of growth from 4- to 16-years of age, the pattern of growth was visibly different and requires further investigation.
Although the abnormal growth trajectory is clear, the reasoning behind it is less so. Boys with ASD had longer limbs than TD boys, indicating possible connective tissue abnormalities. The HPA axis may also be involved, as more severe autistic symptoms were correlated with a greater CAR and with being large overall. Further research is required to determine if boys who are large overall also have increased CAR and represent a biologically distinct subgroup within ASD.
This document summarizes a study that examined the effects of an eating disorder prevention program on eating disorder characteristics among adolescent ballet dancers. The study had two aims: 1) to have adolescent ballet dancers complete an eating disorder prevention program and compare outcomes to a control group, and 2) to measure eating disorder characteristics before, immediately after, and 6 months post-intervention using the Eating Disorder Inventory-3. The literature review discusses eating disorder prevalence among adolescent dancers, risk factors like perfectionism, and previous prevention programs aimed at dancers.
1) This study examined the effects of an 8-week physical exercise program on happiness among 120 older adults in Iran.
2) Participants were randomly assigned to an experimental group that participated in the exercise program or a control group.
3) Results showed that the exercise program significantly improved happiness in the experimental group, while happiness did not improve in the control group.
The Beighton score is a valid measure for generalized hypermobility in children ages 6 to 12 based on this study of 551 Dutch children. More than 35% of children scored above the cutoff of 5/9 on the Beighton scale, indicating increased joint mobility. Children with higher Beighton scores showed increased range of motion in other joints measured as well. There were no significant differences in prevalence of joint pain or pain after exercise between groups with different Beighton scores. The Beighton score effectively measured generalized joint mobility in this population of school-aged children.
Assessment of nutritional status of children in al hilla cityAlexander Decker
This study assessed the nutritional status of 211 children ages 6-12 in Al Hilla City, Iraq. 73 children were underweight, 100 were overweight or obese, and 38 were a normal weight. There was a higher prevalence of underweight in girls (66%) than boys (34%), and of overweight and obesity in boys (66% and 57%) than girls (34% and 43%). Factors associated with underweight included rural residence, low family income, and mothers who worked. Factors linked to overweight and obesity included sedentary lifestyles, spending excessive time watching TV and using computers, and not being breastfed as infants. The study concluded that inactivity and screen time are risk factors for childhood obesity,
This document provides a bibliography of references related to physical activity and youth. It includes 58 references from 1998 to 2013 on topics such as:
- Physical activity levels and health outcomes in children and adolescents from different countries.
- Relationships between physical activity, sedentary behaviors like TV watching, and health indicators.
- Guidelines and recommendations around physical activity for youth.
- Trends in physical activity and participation in sports over time.
This document discusses changing paradigms in youth sports toward more child-centered models. It outlines trends toward early sports specialization and their negative consequences. It then reviews various youth development models that emphasize motor skill development, physical literacy, and diversified play over early specialization. The Long-Term Athletic Development model framework promotes multi-sport participation and developmentally-appropriate training across childhood. Coaching approaches discussed include focusing on fun, skill-building, and limiting instructions to promote child-centered learning and development through sports.
A therapy for physical and mental fitness of school childrenAlexander Decker
This document discusses the importance of physical and mental fitness for school children. It notes that physical fitness involves more than just the absence of disease, but the ability to study efficiently without undue fatigue. Regular graded physical exercises are needed to develop and maintain fitness, but many teachers no longer prioritize this. The physical and mental fitness of pupils has declined as a result. The document argues that schools must make developing and maintaining pupil fitness a priority through organized physical education programs.
The impact of physical activity participation on the self esteem of the stude...Dr. Mohammed Abou Elmagd
Positive self-esteem helps people to feel good about themselves and gives them confidence to do things and confront social challenges. Positive self-esteem is improved by certain factors including increased physical activity. This can be utilized in the university age group, especially when considering medical and health sciences colleges where higher stress levels are recorded. Aim: To assess the relationship between physical activity and self-esteem among medical and health sciences students. Methods: an online questionnaire-based cross sectional study involved 198 students from RAK Medical and Health Sciences University was conducted to identify the level of physical activity and self-esteem score. Results were tabulated and analyzed using SPSS. Results: there was significant positive correlation between physical activity and self-esteem (r = 0.604). However, the correlation was higher for female students with no significant difference. Correlation among colleges did not show significant differences.
Association of lipid profile and waist circumferenc (2)Shahid Nawaz
The study evaluated the association between overweight/obesity and cardiovascular risk factors among 315 Qatari children aged 6-11. It found that overweight and obese children had significantly higher rates of increased waist circumference, hypertriglyceridemia, low HDL levels, and atherogenic index compared to children of normal weight. The results indicate that overweight and obese Qatari children are at greater risk for cardiovascular disease later in life.
Association of lipid profile and waist circumferenc (2)Shahid Nawaz
1) The study evaluated the association between overweight/obesity and cardiovascular risk factors like lipid profiles and waist circumference in Qatari children aged 6-11.
2) Around 31-33% of the children were found to be overweight or obese. Overweight and obese children showed significantly increased risks of high waist circumference, hypertriglyceridemia, low HDL-C, and high atherogenic index.
3) The results indicate that overweight and obese Qatari children have elevated cardiovascular risks related to lipids and waist circumference, suggesting control of excessive weight gain in children could have long-term health benefits.
The document discusses validating the short version of the Physical Activity Enjoyment Scale (S-PACES) for use with Spanish children. An exploratory factor analysis found the S-PACES has good reliability and measures enjoyment as a single factor. Scores on the S-PACES correlated positively with intrinsic motivation and negatively with amotivation and BMI z-score. While there was no difference in scores between normal weight and overweight children, enjoyment of physical activity decreased as BMI z-score increased. The study concludes the S-PACES is a useful tool for measuring enjoyment of physical activity in Spanish children.
El documento describe los servicios y actividades que ofrece Agua Viva, incluyendo clases de natación para bebés, niños, adultos y alto rendimiento, así como aquafitness y entrenamiento en gimnasio. También resume brevemente la historia de Agua Viva, desde sus inicios en 1991 hasta la actualidad, donde cuenta con instalaciones ampliadas como gimnasio, salones y vestidores.
The author reflects on their experience completing a Master's degree in Disability Studies. They discuss how the rigorous curriculum and hands-on experience working with clients increased their confidence, compassion, and understanding of how to advocate for marginalized groups. Their sympathy for those living with disabilities grew into true compassion through their studies and clinical work. The program challenged them but also provided an enriching experience that prepared them to fulfill their goal of empowering people with disabilities through advocacy.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCESjk_l33 mn_3l
This document discusses the influence of intensive physical training on growth and pubertal development in athletes. It finds that:
1) Intensive training can negatively influence growth, especially in artistic gymnastics where both male and female gymnasts exhibited attenuated growth potential compared to their genetic predisposition and target height.
2) In rhythmic gymnasts, genetic predisposition to growth was preserved and even exceeded, as rhythmic gymnasts continued growing into later ages and achieved heights above their target heights.
3) In most other sports not requiring strict dietary restrictions, no negative impact on growth was found. Intensive training delayed pubertal development and sexual maturation in various sports, especially gymnastics,
The influence of intensive physical training on growth and pubertal developm...jk_l33 mn_3l
This document discusses the influence of intensive physical training on growth and pubertal development in athletes. It finds that:
1) Intensive training can negatively influence growth, especially in artistic gymnastics where it was found to attenuate growth potential more in males than females.
2) In female rhythmic gymnasts, genetic predisposition to growth was preserved and even exceeded due to a late catch-up growth phenomenon.
3) In most other sports not requiring strict dietary restrictions, no negative impact on growth has been documented.
4) Intensive training and negative energy balance can delay pubertal development and prolong the prepubertal stage in various sports, with effects being more pronounced in gym
A Practical Measure of Balance, Gait, and Muscular Power in Older Adults: The...Kyle Menkosky
This document describes the Short Physical Performance Battery (SPPB), which is a validated test used to assess physical function in older adults. The SPPB examines balance, gait, and lower body strength through tests of standing balance, walking speed, and repeated chair stands. It provides an overall score of 0-12 based on performance in each test. Studies have shown SPPB scores predict disability, nursing home admission, and mortality in older adults. The document argues the SPPB is a practical test that can be used in cardiac and pulmonary rehabilitation to safely identify frailty and guide exercise interventions to improve outcomes in older patients.
This document outlines a study on factors associated with physical inactivity among first year undergraduate students at Universiti Putra Malaysia. It includes a literature review on previous research examining relationships between physical inactivity and socio-demographic factors, environmental support, mental health, self-efficacy, and body image. The document presents the study objectives, conceptual framework, and methodology, which will involve a cross-sectional study using cluster sampling of first year undergraduates to examine associations between physical inactivity and various independent variables.
Cognitive Benefits of Exercise for Children and TeensMark Dreher PhD
The brain evolves during our childhood years as it continues to develop and is affected by lifestyle habits such as physical activity, cognitive activity, nutrition and sleep.
Although there is growing scientific evidence that exercise is associated with improved cognitive function, academic performance, and overall health in children, the limited amount of time generally dedicated to physical activity during the school day continues to decline in many schools.
The activity requirements for healthy brain and cognitive function are really relatively modest. For children, moderate aerobic activity of about 60 minutes a day can make a big difference, especially in children that are currently low-performers. There is work to be done in the United States and other countries to meet these activity goals as only about 30% of high school students achieve them.
This presentation provides a current summary of the human research on aerobic exercise and cognitive function in children and teens.
Mark Dreher PhD
This study examined the relationship between various modes of physical activity (PA) and academic achievement in adolescents. It found that:
1) Males engaged in higher levels of PA than females across most modes measured, including habitual PA, active transport, physical education, extra-curricular sport, and community-based sport.
2) For males, habitual PA and physical education minutes were positively correlated with academic achievement. For females, only physical education minutes were positively correlated.
3) Physical education minutes emerged as the strongest predictor of academic achievement for both males and females in regression analysis.
The study concluded that physical education should be adequately included in the school curriculum due to its associations with academic achievement. It also noted
A Comprehensive Mixed-Longitudinal Study of Growth in Boys with Autism Spectr...Cherie Green
The first aim in the current study was to replicate previous findings indicating a phase of early overgrowth of HC, height and weight. The second aim was to investigate if growth dysregulation was also apparent in older children and adolescents with ASD. If a general growth dysregulation was found in boys with ASD from birth - 16 years of age, it was hypothesized that this growth dysregulation may be the result of either 1) connective tissue abnormalities, and/or
2) dysregulation of the HPA axis. A further exploratory aim was to identify biologically distinct subgroups within ASD based on specific growth, behavioural, and biological patterns.
The results from both Study 1 and 2 confirmed that an overall growth dysregulation exists in ASD. Boys with ASD are smaller at birth, but then grow at a faster rate, so that by 4 years of age they are larger than TD boys. They then stay larger throughout childhood and adolescence. Although there were no group differences in the overall rate of growth from 4- to 16-years of age, the pattern of growth was visibly different and requires further investigation.
Although the abnormal growth trajectory is clear, the reasoning behind it is less so. Boys with ASD had longer limbs than TD boys, indicating possible connective tissue abnormalities. The HPA axis may also be involved, as more severe autistic symptoms were correlated with a greater CAR and with being large overall. Further research is required to determine if boys who are large overall also have increased CAR and represent a biologically distinct subgroup within ASD.
This document summarizes a study that examined the effects of an eating disorder prevention program on eating disorder characteristics among adolescent ballet dancers. The study had two aims: 1) to have adolescent ballet dancers complete an eating disorder prevention program and compare outcomes to a control group, and 2) to measure eating disorder characteristics before, immediately after, and 6 months post-intervention using the Eating Disorder Inventory-3. The literature review discusses eating disorder prevalence among adolescent dancers, risk factors like perfectionism, and previous prevention programs aimed at dancers.
1) This study examined the effects of an 8-week physical exercise program on happiness among 120 older adults in Iran.
2) Participants were randomly assigned to an experimental group that participated in the exercise program or a control group.
3) Results showed that the exercise program significantly improved happiness in the experimental group, while happiness did not improve in the control group.
The Beighton score is a valid measure for generalized hypermobility in children ages 6 to 12 based on this study of 551 Dutch children. More than 35% of children scored above the cutoff of 5/9 on the Beighton scale, indicating increased joint mobility. Children with higher Beighton scores showed increased range of motion in other joints measured as well. There were no significant differences in prevalence of joint pain or pain after exercise between groups with different Beighton scores. The Beighton score effectively measured generalized joint mobility in this population of school-aged children.
Assessment of nutritional status of children in al hilla cityAlexander Decker
This study assessed the nutritional status of 211 children ages 6-12 in Al Hilla City, Iraq. 73 children were underweight, 100 were overweight or obese, and 38 were a normal weight. There was a higher prevalence of underweight in girls (66%) than boys (34%), and of overweight and obesity in boys (66% and 57%) than girls (34% and 43%). Factors associated with underweight included rural residence, low family income, and mothers who worked. Factors linked to overweight and obesity included sedentary lifestyles, spending excessive time watching TV and using computers, and not being breastfed as infants. The study concluded that inactivity and screen time are risk factors for childhood obesity,
This document provides a bibliography of references related to physical activity and youth. It includes 58 references from 1998 to 2013 on topics such as:
- Physical activity levels and health outcomes in children and adolescents from different countries.
- Relationships between physical activity, sedentary behaviors like TV watching, and health indicators.
- Guidelines and recommendations around physical activity for youth.
- Trends in physical activity and participation in sports over time.
This document discusses changing paradigms in youth sports toward more child-centered models. It outlines trends toward early sports specialization and their negative consequences. It then reviews various youth development models that emphasize motor skill development, physical literacy, and diversified play over early specialization. The Long-Term Athletic Development model framework promotes multi-sport participation and developmentally-appropriate training across childhood. Coaching approaches discussed include focusing on fun, skill-building, and limiting instructions to promote child-centered learning and development through sports.
A therapy for physical and mental fitness of school childrenAlexander Decker
This document discusses the importance of physical and mental fitness for school children. It notes that physical fitness involves more than just the absence of disease, but the ability to study efficiently without undue fatigue. Regular graded physical exercises are needed to develop and maintain fitness, but many teachers no longer prioritize this. The physical and mental fitness of pupils has declined as a result. The document argues that schools must make developing and maintaining pupil fitness a priority through organized physical education programs.
The impact of physical activity participation on the self esteem of the stude...Dr. Mohammed Abou Elmagd
Positive self-esteem helps people to feel good about themselves and gives them confidence to do things and confront social challenges. Positive self-esteem is improved by certain factors including increased physical activity. This can be utilized in the university age group, especially when considering medical and health sciences colleges where higher stress levels are recorded. Aim: To assess the relationship between physical activity and self-esteem among medical and health sciences students. Methods: an online questionnaire-based cross sectional study involved 198 students from RAK Medical and Health Sciences University was conducted to identify the level of physical activity and self-esteem score. Results were tabulated and analyzed using SPSS. Results: there was significant positive correlation between physical activity and self-esteem (r = 0.604). However, the correlation was higher for female students with no significant difference. Correlation among colleges did not show significant differences.
Association of lipid profile and waist circumferenc (2)Shahid Nawaz
The study evaluated the association between overweight/obesity and cardiovascular risk factors among 315 Qatari children aged 6-11. It found that overweight and obese children had significantly higher rates of increased waist circumference, hypertriglyceridemia, low HDL levels, and atherogenic index compared to children of normal weight. The results indicate that overweight and obese Qatari children are at greater risk for cardiovascular disease later in life.
Association of lipid profile and waist circumferenc (2)Shahid Nawaz
1) The study evaluated the association between overweight/obesity and cardiovascular risk factors like lipid profiles and waist circumference in Qatari children aged 6-11.
2) Around 31-33% of the children were found to be overweight or obese. Overweight and obese children showed significantly increased risks of high waist circumference, hypertriglyceridemia, low HDL-C, and high atherogenic index.
3) The results indicate that overweight and obese Qatari children have elevated cardiovascular risks related to lipids and waist circumference, suggesting control of excessive weight gain in children could have long-term health benefits.
The document discusses validating the short version of the Physical Activity Enjoyment Scale (S-PACES) for use with Spanish children. An exploratory factor analysis found the S-PACES has good reliability and measures enjoyment as a single factor. Scores on the S-PACES correlated positively with intrinsic motivation and negatively with amotivation and BMI z-score. While there was no difference in scores between normal weight and overweight children, enjoyment of physical activity decreased as BMI z-score increased. The study concludes the S-PACES is a useful tool for measuring enjoyment of physical activity in Spanish children.
El documento describe los servicios y actividades que ofrece Agua Viva, incluyendo clases de natación para bebés, niños, adultos y alto rendimiento, así como aquafitness y entrenamiento en gimnasio. También resume brevemente la historia de Agua Viva, desde sus inicios en 1991 hasta la actualidad, donde cuenta con instalaciones ampliadas como gimnasio, salones y vestidores.
The author reflects on their experience completing a Master's degree in Disability Studies. They discuss how the rigorous curriculum and hands-on experience working with clients increased their confidence, compassion, and understanding of how to advocate for marginalized groups. Their sympathy for those living with disabilities grew into true compassion through their studies and clinical work. The program challenged them but also provided an enriching experience that prepared them to fulfill their goal of empowering people with disabilities through advocacy.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCESjk_l33 mn_3l
This document discusses the influence of intensive physical training on growth and pubertal development in athletes. It finds that:
1) Intensive training can negatively influence growth, especially in artistic gymnastics where both male and female gymnasts exhibited attenuated growth potential compared to their genetic predisposition and target height.
2) In rhythmic gymnasts, genetic predisposition to growth was preserved and even exceeded, as rhythmic gymnasts continued growing into later ages and achieved heights above their target heights.
3) In most other sports not requiring strict dietary restrictions, no negative impact on growth was found. Intensive training delayed pubertal development and sexual maturation in various sports, especially gymnastics,
The influence of intensive physical training on growth and pubertal developm...jk_l33 mn_3l
This document discusses the influence of intensive physical training on growth and pubertal development in athletes. It finds that:
1) Intensive training can negatively influence growth, especially in artistic gymnastics where it was found to attenuate growth potential more in males than females.
2) In female rhythmic gymnasts, genetic predisposition to growth was preserved and even exceeded due to a late catch-up growth phenomenon.
3) In most other sports not requiring strict dietary restrictions, no negative impact on growth has been documented.
4) Intensive training and negative energy balance can delay pubertal development and prolong the prepubertal stage in various sports, with effects being more pronounced in gym
The document discusses the development of a mobile app called "GB Queen's Award Buddy" to help Girls' Brigade members complete their Queen's Award certificate. The Queen's Award programme takes place over two years for girls aged 16 to 25 but has a high dropout rate due to the difficulty of organizing the various requirements. The app aims to lower the dropout rate by allowing users to track their progress, set reminders, and communicate with others. It would provide features like hours and word counters, reminders, and a secure chat function. The app developers believe this specialized tool could significantly help girls earn the qualification by making the process easier to manage.
This document provides information about studying in Germany. It outlines that Germany has a strong and growing economy and degrees are recognized worldwide. Students need to submit documents like a high school diploma, CV, and German language certificate. Non-native German speakers must pass the DSH or TestDaF exams to prove their German language ability. Studies are affordable, with student fees between 200-600 Euros per semester and many discounts available. The deadline to apply is July 15th for the winter term or January 15th for the summer term.
This study examined bone mineral density (BMD) in 54 children and adolescents with juvenile idiopathic arthritis before and after a 12-week exercise program. The participants were randomly assigned to an exercise group or control group. The exercise group performed 100 two-footed jumps with a rope and muscle strength exercises 3 times per week. BMD was measured at the start, after 3 months, and after 6 months using dual-energy x-ray absorptiometry. The results showed that BMD values in the total body increased significantly in the exercise group after the program, while BMD measurements remained stable in the control group and for all participants remained within the normal reference range compared to other children. Thus, a short-
POSITION STATEMENTOveruse Injuries and Burnout in Youth Sp.docxharrisonhoward80223
POSITION STATEMENT
Overuse Injuries and Burnout in Youth Sports:
A Position Statement from the American Medical Society for
Sports Medicine
John P. DiFiori, MD,* Holly J. Benjamin, MD,† Joel Brenner, MD, MPH,‡ Andrew Gregory, MD,§
Neeru Jayanthi, MD,¶ Greg L. Landry, MD,∥ and Anthony Luke, MD, MPH**
(Clin J Sport Med 2014;24:3–20)
Executive Summary
BACKGROUND
• Youth sport participation offers many benefits including
the development of self-esteem, peer socialization, and
general fitness.
• However, an emphasis on competitive success, often driven
by goals of elite-level travel team selection, collegiate schol-
arships, Olympic and National team membership, and even
professional contracts, has seemingly become widespread.
• This has resulted in increased pressure to begin high-
intensity training at young ages.
• Such an excessive focus on early intensive training and
competition at young ages rather than skill development
can lead to overuse injury and burnout.
PURPOSE
• To provide a systematic, evidenced-based review that will:
∘ Assist clinicians in recognizing young athletes at risk
for overuse injuries and burnout.
∘ Delineate the risk factors and injuries that are unique to
the skeletally immature young athlete.
∘ Describe specific high-risk overuse injuries that present
management challenges and/or can lead to long-term
health consequences.
∘ Summarize the risk factors and symptoms associated
with burnout in young athletes.
∘ Provide recommendations on overuse injury prevention.
METHODOLOGY
• Medical Subject Headings (MeSHs) and text words were
searched on March 26, 2012, for MEDLINE, CINAHL,
and PsychINFO.
• Nine hundred fifty-three unique articles were initially
identified. Additional articles were found using cross-
referencing. The process was repeated July 10, 2013,
to review any new articles since the original search.
• Screening by the authors yielded a total of 208 relevant
sources that were used for this paper.
• Recommendations were classified using the Strength of
Recommendation Taxonomy (SORT) grading system.
DEFINITION OF OVERUSE INJURY
• Overuse injuries occur due to repetitive submaximal
loading of the musculoskeletal system when rest is not
adequate to allow for structural adaptation to take place.
• Injury can involve the muscle-tendon unit, bone, bursa,
neurovascular structures, and the physis.
• Overuse injuries unique to young athletes include apoph-
yseal injuries and physeal stress injuries.
EPIDEMIOLOGY
• It is estimated that 27 million US youth between 6 to 18
years of age participate in team sports.
• The National Council of Youth Sports survey found that
60 million children aged 6 to 18 years participate in some
Submitted for publication November 2, 2013; accepted November 6, 2013.
From the *Division of Sports Medicine and Non-Operative Orthopaedics, Depart-
ments of Family Medicine and Orthopaedics, University of California, Los
Angeles, California; †Departments of Pediatrics an.
This document discusses exercise physiology in pediatrics from ages 0-22. It covers growth, development and maturation processes and divides the period of life into infancy, childhood, and adolescence. It also summarizes the development of body tissues, organ systems, and fitness norms at different ages. Key physiological responses to exercise like heart rate, lung function, and metabolic capacity are described across childhood and adolescence.
Nutrition, Sports, and Covid-19 Lockdown Impact on Young Competitive Artistic...Austin Publishing Group
Young artistic swimmers require a variety of athletic abilities for their sport and have high energy needs. The COVID-19 lockdown disrupted their training and highlighted issues with their nutrition. A study of 25 young female artistic swimmers found that during the lockdown, their macronutrient intake ratios were inverted from recommendations, with lower energy intake versus needs. Young athletes, families, and coaches need better nutrition guidelines and education to support healthy food choices that meet athletes' growth and performance needs.
- Resistance training (RT) can provide health and fitness benefits for youth if properly designed and supervised. While previously thought to be ineffective and risky, research now shows RT can significantly increase strength in youth beyond normal growth levels with a low risk of injury.
- Potential risks of RT for youth include injury to growth plates, psychological harm, and overuse soft tissue injuries. However, no injuries have been reported in supervised youth RT programs, and studies show RT can improve psychological well-being in youth. Risks are low when age-appropriate guidelines are followed and supervision is provided.
- Common overuse injuries in youth from RT include muscle strains, especially in the lower back. Many injuries result from weaknesses, improper technique,
Evidence based physical activity for school age youthbeatriz9911
This document summarizes an expert panel's review of evidence on the effects of physical activity on health outcomes in school-age youth. The panel identified over 850 relevant articles through a systematic search. They found:
1) Most intervention studies showed benefits of 30-45 minutes per day of moderate to vigorous physical activity 3-5 days per week. However, the panel believed greater amounts would be needed for benefits under normal circumstances.
2) The panel concluded that school-age youth should participate in 60 minutes or more per day of moderate to vigorous physical activity from a variety of activities.
3) Physical activity was associated with reduced adiposity, especially for overweight youth, and improved cardiovascular health factors like blood lipid levels and aer
Abstract—
A birth weight that is too small could signal the occurrence of growth disorders or even growth deficiency, as well as a variety of disorders of bodily functions, including impaired glucose tolerance, insulin resistance and hypertension. However, so far the relation between birth weight and aerobic capacity has not been studied.
Objective: To compare the aerobic capacity of physically active young adults with different birth weights.
Methods: 159 people born at full term of a single pregnancy (F: 45%, n = 71; M: n = 88), first-year students studying Physical Education. In all cases the subjects’ body composition was estimated, height and weight (BW) was measured, and the maximal oxygen uptake during exercises performed on an ergometer bicycle was established.
Results: the smallest birth body weight (BBW) was 2200 g; 3% of students (n = 5) were born with a BBW of less than 2500 g, and only 2% were born with BBW deficiency (<2><1> 2 s);
2. We suggest that when enrolling women for sports disciplines requiring their best aerobic capacity, birth weight should be taken into consideration, and based on the observations from the study it is furthermore suggested that a search for talent should be conducted among girls with BBW between 2300 and 3800 g.
Physical literacy presenation USC Sport conferenceMark McKean
This document summarizes research on physical literacy and movement competency in children. It discusses how low physical literacy is linked to issues like obesity and inactivity. The research aims to assess movement competency in primary school children using tests of 7 fundamental movements and skills. Initial results show a relationship between better performance on movement tests and meeting daily physical activity guidelines. Girls generally scored higher than boys. The research will next implement an intervention using movement breaks and modified PE lessons to improve competency over the school year while monitoring changes. The goal is to better understand movement competency and how it relates to lifestyle factors and physical literacy.
The impact of physical activity on academic performance among medical and hea...Dr. Mohammed Abou Elmagd
Physical activity is a crucial component of school curricula as it is suggested to increase the students’ academic performance. This may be applied in the university age group, especially when considering medical and health sciences colleges where higher stress levels are recorded. Aim: To assess the relationship between physical activity and academic performance among medical and health sciences students. Methods: an online questionnaire-based cross sectional study involved 198 students from RAK Medical and Health Sciences University was conducted to identify the level of physical activity and academic performance. Results were tabulated and analyzed using SPSS. Results: there was significant positive correlation between physical activity and academic performance (r = 0.208). However, the correlation was higher for BDS College with no significant difference with regard to nationality, age and gender.
ORIGINALARTICLESEVIDENCE BASED PHYSICAL ACTIVITY FOR SCH.docxalfred4lewis58146
ORIGINAL
ARTICLES
EVIDENCE BASED PHYSICAL ACTIVITY FOR SCHOOL-AGE YOUTH
WILLIAM B. STRONG, MD,* ROBERT M. MALINA, PHD,* CAMERON J. R. BLIMKIE, PHD, STEPHEN R. DANIELS, MD, PHD,
RODNEY K. DISHMAN, PHD, BERNARD GUTIN, PHD, ALBERT C. HERGENROEDER, MD, AVIVA MUST, PHD, PATRICIA A. NIXON, PHD,
JAMES M. PIVARNIK, PHD, THOMAS ROWLAND, MD, STEWART TROST, PHD, AND FRANCxOIS TRUDEAU, PHD
Objectives To review the effects of physical activity on health and behavior outcomes and develop evidence-based
recommendations for physical activity in youth.
Study design A systematic literature review identified 850 articles; additional papers were identified by the expert
panelists. Articles in the identified outcome areas were reviewed, evaluated and summarized by an expert panelist. The strength
of the evidence, conclusions, key issues, and gaps in the evidence were abstracted in a standardized format and presented and
discussed by panelists and organizational representatives.
Results Most intervention studies used supervised programs of moderate to vigorous physical activity of 30 to 45 minutes
duration 3 to 5 days per week. The panel believed that a greater amount of physical activity would be necessary to achieve similar
beneficial effects on health and behavioral outcomes in ordinary daily circumstances (typically intermittent and unsupervised
activity).
Conclusion School-age youth should participate daily in 60 minutes or more of moderate to vigorous physical activity that
is developmentally appropriate, enjoyable, and involves a variety of activities. (J Pediatr 2005;146:732-7)
R
ecommendations for appropriate amounts of physical activity for the US
population, including school-age youth, have been developed by several
organizations and agencies.1 Although recent reviews have summarized the
benefits of regular physical activity on the health of youth and its potential for reducing the
incidence of chronic diseases that are manifested in adulthood,
2-5
a more systematic
approach is indicated. This report presents results of a systematic evaluation of evidence
dealing with the effects of regular physical activity on several health and behavioral
outcomes in US school-age youth, with the goal of developing a recommendation for the
amount of physical activity deemed appropriate to yield beneficial health and behavioral
outcomes.
METHOD
Under a contract with the Divisions of Nutrition and Physical Activity and
Adolescent and School Health of the Centers for Disease Control and Prevention and the
Constella Group, an expert panel was convened to review and evaluate available evidence
on the influence of physical activity on several health and behavioral outcomes in youth
aged 6 to 18 years. The co-chairs of the panel selected panelists on the basis of expertise in
specific areas: adiposity, cardiovascular health (lipids and lipoproteins, blood pressure, the
metabolic syndrome, type 2 diabetes mellitus, cardiovascular reactivity, heart rate
variab.
This document discusses at what age it is too young to start strength and conditioning training programs for youth. The key points are:
1) Participation in youth sports is increasing, leading more children to start strength training at younger ages. However, concerns have been raised about safety.
2) Starting integrative neuromuscular training (INT) programs early can help children develop motor skills and reduce injury risk by increasing their "training age". Training age refers to the duration and consistency of a child's participation in physical activities and training programs.
3) INT programs that incorporate strength, power, agility and other exercises can safely and effectively train children as young as ages 6-8, provided the training is
This study investigated the relationship between body fat percentage and physical fitness performance among 30 male basketball players aged 19-25 who participated in intervarsity games. The AAHPER test was used to measure physical fitness, while the Jackson & Pollock equation was used to determine body fat percentage. Pearson's correlation found a significant relationship between higher body fat percentage and lower physical fitness performance. This suggests that increased body fat negatively impacts athletic performance in sports requiring body movement.
The document discusses growth and development from an orthodontic perspective. It covers several key points:
1. Growth involves increases in size, changes in proportions, and increasing complexity over time from embryological development through childhood, adolescence and adulthood.
2. Factors like heredity, nutrition, illness, socioeconomics, and environment can influence growth.
3. Growth occurs in rhythmic patterns with growth spurts, including one in early childhood and another during adolescence.
4. Understanding normal growth patterns, variability, and timing is important for orthodontic treatment planning and assessment.
2 y, 16 CEC
Associate: 2 y, 24 CEC
Master: 2 y, 32 CEC
2 y, CEC 24 h
2 y, CEC 24 h
2 y, CEC 24 h
2 y, CEC 24 h
2 y, CEC 24 h
Recertification
Requirements
CEC indicates continuing education credits; MC, multiple choice; NSPA, National Strength Professionals Association.
Home examination
Home examination
Written examination, 150 MC questions,
proctored examination
Written examination, 150 MC questions,
proctored examination
Written examination, 150 MC questions,
proct
Adolescent athletes face unique physical and mental health challenges due to the cognitive, emotional, and physical changes during this developmental period. It is important to support healthy nutrition, prevent overtraining and injuries, address potential eating disorders, and promote cognitive development in adolescent athletes. Coaches, trainers, parents, and schools all play a role in educating young athletes to make choices that optimize both physical performance and long-term well-being.
The document discusses 10 common myths about youth strength training and provides evidence against each myth. It finds that strength training is safe and beneficial for youth when performed with proper form and supervision. Regular strength training can improve muscle fitness, bone density, body composition, motor skills, and injury resistance in children and teenagers.
- Early sports specialization, or intense training in a single sport at the exclusion of others from a young age, has been associated with increased injury risk and attrition from sports. Specialization occurs earlier in individual sports than team sports.
- A systematic review examined the effects of early specialization on youth and adolescent athletes. Several studies found that early specialization was linked to higher rates of overuse injuries and dropping out of sports during young adulthood. However, the evidence on optimal timing of specialization is still limited.
- Athletic trainers should educate young athletes, parents, and coaches on the risks of early specialization, including overuse injuries, and encourage taking adequate rest and participating in multiple sports while young.
Seminar - Growth and Development and theories of growthMMCDSR , Haryana
Growth and development are complex processes involving both quantitative and qualitative changes over time. Growth refers mainly to increases in size, while development involves increasing organization and complexity of structures and functions. Several theories attempt to explain the patterns and mechanisms of growth, including concepts of growth fields, drift, and remodeling. Understanding the genetic influences and multiple factors that can affect growth timing and rates is important for orthodontic treatment planning.
The study explored the incidence of athlete burnout among youth, high school, and college athletes and examined the associations between competitive trait anxiety, personal control, and athlete burnout. A sample of 153 athletes completed questionnaires measuring burnout, anxiety, and perceived control. Results showed a low overall incidence of burnout. A positive relationship was found between burnout and anxiety, and a negative relationship between burnout and perceived control. Younger athletes reported lower burnout than older athletes, and women reported higher burnout than men.
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1. Ann. N.Y. Acad. Sci. ISSN 0077-8923
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
Issue: Women’s Health and Disease
The influence of intensive physical training on growth
and pubertal development in athletes
Neoklis A. Georgopoulos,1
Nikolaos D. Roupas,1
Anastasia Theodoropoulou,2
Athanasios Tsekouras,2
Apostolos G. Vagenakis,2
and Kostas B. Markou2
1
Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, University of Patras Medical School,
University Hospital, Patras, Greece. 2
Division of Endocrinology, Department of Medicine, University of Patras Medical School,
University Hospital, Patras, Greece
Address for correspondence: Neoklis A. Georgopoulos, Division of Reproductive Endocrinology, Department of Obstetrics
and Gynecology, University of Patras Medical School, University Hospital, Rio-26500, Patras, Greece. neoklisg@hol.gr
Genetic potential for growth can be fully expressed only under favorable environmental conditions. Although
moderate physical activity has beneficial effects on growth, excessive physical training may negatively affect it. Sports
favoring restricted energy availability, in the presence of high energy expenditure, are of particular concern. In
gymnastics, a different pattern in skeletal maturation and linear growth was observed, resulting in an attenuation
of growth potential in artistic gymnasts (AG), more pronounced in males than in females. In female rhythmic
gymnasts (RG), the genetic predisposition to growth was preserved owing to a late catchup growth phenomenon.
In all other sports not requiring strict dietary restrictions, no deterioration of growth has been documented so
far. Intensive physical training and negative energy balance alter the hypothalamic pituitary set point at puberty,
prolong the prepubertal stage, and delay pubertal development and menarche in a variety of sports. In elite RG and
AG, prepubertal stage is prolonged and pubertal development is entirely shifted to a later age, following the bone
maturation rather than the chronological age.
Keywords: athletes; gymnasts; growth; pubertal development; skeletal maturation; bone acquisition
Introduction
Somatic growth and biological maturation are dy-
namic processes regulated by a variety of genetic and
environmental factors. Changes in body composi-
tion, in body proportions, in skeletal maturation,
and in pubertal development constitute indispens-
able components in the evaluation of the growth
process,complementingthetraditionalaspectofthe
assessment of stature as the main focus of growth
evaluation. Thus, growth and physical maturation
should be regarded as a complex, and dynamic pro-
cess, including a large variety of molecular and so-
matic changes.
Genetic predisposition to growth can be fully
expressed only under favorable environmental
conditions.1
Environmental factors can act inde-
pendently or in combination to modify the individ-
ual genetic potential. Athletic training when exerted
during childhood and adolescence has a huge im-
pact on physical growth and pubertal maturation.
There is strong evidence that regular physical ac-
tivity is important for good body function and de-
velopment. At the same time, there is a growing
concern regarding the influence of stress and inten-
sivephysicaltrainingongeneralhealth.Beginningat
an early age, athletes performing at a high compet-
itive level are exposed to high levels of physical and
psychological stress resulting from many hours of
intense training and competitions. The damaging
effects of these factors on somatic growth, skele-
tal, and pubertal maturation, have been described
in individuals performing a variety of sports. Indi-
vidual sports exert unique influences on biological
maturation, depending on the sport-related specific
character, technical skills and training methods and
the stage of growth and sexual maturation of the
individual athlete. Therefore, the whole picture is
doi: 10.1111/j.1749-6632.2010.05677.x
Ann. N.Y. Acad. Sci. 1205 (2010) 39–44 c 2010 New York Academy of Sciences. 39
2. Growth in athletes Georgopoulos et al.
extremely complex and should be approached with
extreme caution and responsibility.
Somatic growth in athletes
The major factor influencing linear growth is ge-
netic predisposition. Both adult final height and the
rate of growth are greatly influenced by genetic fac-
tors.2
Studies involving twins, revealed that the aver-
age difference in final height between monozygotic
twins was less than 3 cm, compared to 12 cm for
dizygotic twins.3
Final height is best correlated to
target height (midparental height) especially when
parents are not of disparate heights.4
Environment
and heredity continuously interact throughout the
entire period of growth. Children with similar ge-
netic potential are expected to reach comparable
final height under optimal environmental condi-
tions. On the other hand, children with the same
genetic background exposed to entirely different en-
vironmental conditions, can end up with a different
adult height. Furthermore, children of parents from
underdeveloped areas, born and raised in industri-
alized countries, present taller as adults, compared
to their target height. In industrialized countries, an
increase in height has been documented, attributed
to the improvement in socioeconomic conditions.1
Growth and maturation are complex processes
and genetic predisposition is achieved only when
favorable conditions exist during the entire period
of growth. Major environmental factors that may
alter somatic growth are intensive physical exercise
and stress. The impact of stress and intensive phys-
ical training on growth depends on the combined
effects of intensity, frequency, and duration of exer-
cise. Intensive athletic training of 18 hours per week
is capable of attenuating growth.5
Although moder-
ate physical activity has beneficial effects on growth,
as it is associated with cardiovascular benefits and
favorable changes in body composition, extensive
physical training may negatively affect growth, es-
pecially during puberty.6
The effect of intense phys-
ical training on growth and maturation depends
on a variety of factors, including the type of phys-
ical training, the age of training initiation, and the
intensity of training. Each sport requires a spe-
cific type of exercise and is characterized by unique
athletic demands that favor a particular optimal
somatotype.
The period of maximum training during the
growth process is of particular importance. For ex-
ample, in female gymnasts, the greatest physical ex-
ertion coincides with the period of pubertal devel-
opment, whereas in male gymnasts, the maximum
training is required toward the end of puberty. Over
the past few decades, the demands of high compe-
tition level have increased the intensity of training
within the same sport. For example, it is known that
gymnasts are trained much more intensely nowa-
days than previously, usually 26–32 hours per week
compared to 15 h during the seventies and 20 h
during the eighties.
Sports that require a strict control of energy in-
put in combination with a high energy output are of
particular concern. Thus, it is not reasonable to gen-
eralize when trying to evaluate the particular effects
of the activity of each sport on somatic growth. The
major sports that require intensive physical training
during childhood and adolescence are mainly gym-
nastics (both Rhythmic and Artistic), and to a lesser
extent swimming, rowing, wrestling, track and field
athletism, and tennis.
Rhythmic gymnasts (RG) and artistic gymnasts
(AG)aretwodistinctgroupswithinthefieldofgym-
nastics. They include different training methods,
athleticperformanceobjectives,andrequirespecial-
ized and distinct skills. Each sport is characterized
by specific athletic requirements that favor a partic-
ularoptimalsomatotype.Ashort-limbedindividual
would have a greater mechanical advantage in artis-
tic gymnastic performance, whereas a long-limbed
individual could benefit from a similar advantage in
rhythmic gymnastics. Indeed, performance scores
in elite female artistic gymnasts are negatively cor-
related with the degree of fatness or endomorphy
of the individual.7
Therefore, trainers (coaches) ex-
pectedly select individuals that best match certain
anthropometric criteria for each sport. The sport-
specific selection criteria for artistic gymnastics im-
ply that a short stature with relatively short limbs,
broad shoulders, and narrow hips is due to deter-
mined genetic predisposition, rather than a result
of the specific sport training and performance.8
Thus, genetic predisposition should always be con-
sidered when studying the impact of gymnastics on
growth.
Artistic gymnasts
Until recently, AG anthropometric measurements
andprospectivegrowthpredictionsappearedwithin
normal limits.9–12
In all these reports, the adult
40 Ann. N.Y. Acad. Sci. 1205 (2010) 39–44 c 2010 New York Academy of Sciences.
3. Georgopoulos et al. Growth in athletes
height of AG remained proportional for the re-
ported target height despite the method used to
estimate predicted adult height. Another prospec-
tive study documented a reduction of growth po-
tential and a decrease in mean height predictions
over time, in a smaller group of AG.13
However,
in another study by the same group evidence was
provided that the predicted adult height was not
reduced in AG, demonstrating the inherent inac-
curacy of height predictions.14
Although these data
provide useful information, no definite conclusions
should be made until adult height has been attained.
In a large cross-sectional study, we have shown
that female AG were shorter and lighter than aver-
age, with mean height and weight SD scores below
0 (the 50% percentile), following their respective
target height SD score, which was also below 0.15
However, the actually measured height was lower
than their target height. The major factors nega-
tively affecting height in AG were low weight, low
body fat, and intensity of training.
The majority of previously reported data referred
only to female AG. We, therefore, evaluated compar-
atively both male and female AG.16
At the time of ex-
amination, although both female and male AG were
shorter than their age-related population mean, fe-
male AG showed a greater height deviation from
their age-related population mean. Male AG pre-
senting with a height closer to their age-related pop-
ulation mean, had a genetic predisposition toward
a much higher final height than female AG. As a re-
sult, the difference between target height and actual
height SD score ( Target height − Actual height SD
score) was greater in males than in females. Consid-
eringthesedata,itisreasonabletoassumethatinAG
the growth process in males might be more suscep-
tible to the detrimental effects of intensive physical
training.
For both sexes, current measured height was cor-
related positively to target height, indicating that
genetic predisposition to growth, although altered,
was not disrupted. In the group of athletes—of both
sexes—that have reached their final adult height, fi-
nalheightfailedtomeettheirgeneticpredisposition,
providing additional evidence for growth attenua-
tion in AG.
Rhythmic gymnasts
In RG, female RG were taller and thinner than av-
erage for age, with height velocity SD score for each
age group above 0 (50% percentile) for all ages.17,18
Interestingly, although linear growth in normal girls
comes to an end by the year of 15, in RG growth con-
tinued up to the age of 18. Their final adult height
was identical to the estimated predicted height at
first evaluation, and higher than the genetically de-
termined target height, denoting that genetic po-
tentials to final height was not only achieved, but
even exceeded. Furthermore, target height was the
only independent parameter proved to positively
influence height velocity, therefore genetic predis-
position remained the main driving force for the
observed efficient catch-up growth. Comparing AG
with RG leads to the conclusion that their reported
target height SD score was similar to their own mea-
sured heights (above 0 for the RG and below 0 for
the AG), indicating once more the determining role
of genetic predisposition and preselection. RG fol-
lowed a growth pattern that was higher than their
reportedtargetheight,whereasAGexhibitedalower
growth pattern.
In conclusion, studies in gymnasts performing at
thehighestcompetitivelevel,documentedadeterio-
ration of growth potential in AG, more pronounced
in males than in females; whereas, in female RG,
the genetic predisposition to growth was not only
preserved, but even exceeded.
Other sports
In all other sports, no deterioration of growth has
been reported. In swimmers, probably due both to
preselection bias by trainers and to high energy in-
put, the currently measured height was well above
the population mean.19–21
Another longitudinal
study, found no impact of regular intensive physical
training on the final height of female swimmers and
tennis players.22
In young distance runners, mean
height for both males and females approximates the
reference medians and estimated height velocities
are, on average, similar to age and sex-specific pop-
ulation means.23
Girls training for approximately 12
hours per week in sports including rowing, track,
and swimming for an average of 4 years during
puberty, revealed no difference in height velocity
compared to the population means, although a ten-
dency towarda slightly laterpeakheightvelocity was
noted.24
Female swimmers training for 8 hours per
week presented, after a follow-up of 2–3 years, nor-
mal heights and normal height velocities compared
to their population means, whereas AG training
Ann. N.Y. Acad. Sci. 1205 (2010) 39–44 c 2010 New York Academy of Sciences. 41
4. Growth in athletes Georgopoulos et al.
for 22 hours per week showed significantly lower
growth velocities.13
Assessment of anthropometric
data of elite junior tennis players, revealed signifi-
cantly taller top ranked, compared to lower ranked,
female tennis players.25
No difference in growth has
been found between seasonal wrestlers and controls
as all changes in dietary intake, body composition,
and muscular strength were reversed during the
post seasonal period.26
Growth rate was assessed
as normal in a large cohort of school wrestlers, al-
though no information was provided whether or
not a lower growth rate was observed during the
sport season followed by a catch-up growth during
the nontraining season.27
Anthropometric charac-
teristics showed that male rowers were similar in
most aspects to a student control sample, whereas
data on a large sample of elite junior rowers showed
a tendency toward a taller height, more pronounced
among finalists compared to nonfinalists, indicating
the influence of preselection bias.28,29
Inconclusion,intensivephysicaltrainingandath-
letic performance at high level did not negatively af-
fect somatic growth in all sports not requiring strict
dietaryrestrictionsleadingtoenergyimbalance.The
attention should be drawn to elite AG of both sexes,
engaged in highly strenuous competitions.
Pubertal development in athletes
Growth specifically refers to increase in body size,
whereas maturation includes the progress leading to
the biologically mature state. Thus, growth cannot
be fully evaluated without determining the timing
and tempo of biological maturation. Puberty is a
dynamic period of development with rapid changes
in body size, shape, and composition. The onset of
puberty corresponds to a specific biological age, as
determined by skeletal maturation, and namely, a
bone age of 13 years for boys and 11 years for girls.30
Prolonged intensive physical training has great im-
pact on skeletal maturation, leading to a signifi-
cant delay in bone age compared to chronological
age. As in the general population, pubertal devel-
opment in highly trained athletes seems to follow
bone age rather than chronological age.31
However,
genetic predisposition and variation among indi-
viduals should always be considered. Specific sports
favor the early matures, whereas others, such as
gymnastics, offer advantage to the later develop-
ing individuals. Therefore, any assessment of sexual
maturation must take into account the biological
indicators of bone age and peak height velocity.
Delayed pubertal development and sexual mat-
uration has been observed in a variety of sports,
mainly gymnastics, dancing, and long-distance run-
ning.32
The documented delay is determined by the
type, the frequency, the intensity, and the duration
of exercise and is more pronounced in sports requir-
ing strict dietary restrictions that result in higher
energy expenditure in the presence of a deficient
energy input. In the case of gymnasts performing
in the high competitive level of the Olympic games,
delayedmenarchehasbeennoted, comparedtohigh
school, college, and club-level athletes.7
Young girls
or adolescents engaged in sports requiring training
less than 15 hours per week do not show menstrual
disturbances or delay in sexual maturation.33
In elite RG and AG, the prepubertal stage was
prolonged and pubertal development was shifted to
a later age, retaining a normal progression rate.15–18
Expectedly, the progression of puberty followed the
bone age rather than the chronological age.16,17
It
is to be underlined that for both RG and AG, pu-
bertal progression, although delayed, was not pro-
longed. Normal girls require an average of 1.96 ±
0.93 years (mean±SD) for their breast development
toprogressfromTannerstageIItoTannerstageIV.34
A comparable period of time was observed for both
RG and AG in our study. Therefore, pubertal matu-
ration was entirely shifted to a later age, maintaining
a normal rate of progression.
The major factor responsible for the delay in the
onset of breast and pubic hair development in both
sports was low body weight. Low body weight re-
flects an energy deficit, prominent in both sports, as
a result of intensive physical training (high energy
expenditure) on the one side and caloric under-
nutrition (low energy input) on the other. Gym-
nasts indeed are subject to a significant energy
drain, occurring early in prepubertal age, and are
highly motivated to achieve low body weight con-
sistent with their sports requirements for a thin
somatotype.
On the other hand, in ballet dancers under high-
energy drain and low-diet intake, a delayed the-
larche and a normal pubarche were noted.35
This
implies that independent central mechanisms are
involved in triggering these aspects of pubertal de-
velopment. Indeed, breast development and sub-
sequently menarche are related to estrogen levels,
42 Ann. N.Y. Acad. Sci. 1205 (2010) 39–44 c 2010 New York Academy of Sciences.
5. Georgopoulos et al. Growth in athletes
whereas pubarche is mainly related to adrenal an-
drogen production.36
In conditions of energy im-
balance and consequent reduction in adipose tissue
mass, estrogen production is decreased and breast
development and menarche are delayed. It is the on-
set,theduration,andtheextentofenergydeficitthat
determine the degree of involvement in all aspects of
pubertal development. Indeed, ballet dancers with
a normal pubarche start their training at the age of
8–9 years of age with only 3.5–7.3 hours per week,
whereas the RG and AG we examined started their
training at the age of 6.4–7.7 years of age with more
than 30 hours of training per week.35
Female athletes involved in a large variety of
sports, including runners, swimmers, tennis play-
ers, ballet dancers, and gymnasts, present a well-
documented delayed menarche.22,35,36–38
In RG,
menarche was significantly delayed compared to
their mothers and not trained sisters, an observa-
tion arguing against a genetic predisposition toward
delayed menarche.18
It is well known that a minimum weight, for,
height and a critical lean, to, fat mass ratio is re-
quired for menarche. According to Frisch theory,
the attainment of a critical percentage of body fat
lowers the metabolic rate and induces a sensitization
of the hypothalamus to gonadal steroids.39
Indeed,
leptin and estrogen production by the adipose tissue
play a central role in triggering menarche.40
These
adjustments reflect a natural adaptation of the body
to high energy demands. In AG and RG, low body
fat, low body weight (low energy input), and pro-
longed intensive physical training (high energy out-
put) were the major factors influencing menarche.
Low body weight, however, remained the most sig-
nificant factor in delaying the onset of puberty. It is
to be noted that in both RG and AG, older athletes
without menarche presented lower height, weight,
and BMI compared to their contemporaries with
menarche.
In conclusion, in RG and AG intensive physical
training and negative energy balance prolong the
prepubertal stage and delay pubertal development,
by regulating the hypothalamic pituitary set point
at puberty, without affecting the duration of the
pubertal process.
Conclusions
Genetic predisposition to growth can be fully ex-
pressed only under favorable environmental con-
ditions. Moderate physical exercise has beneficial
effects on growth as it is associated with cardiovas-
cularbenefitsandfavorablechangesinbodycompo-
sition. Conversely, extensive physical training may
attenuate growth, especially during puberty.
The effect of stress and intensive physical training
on growth and maturity is related to the combined
effects of age of exercise onset, exercise intensity,
exercise frequency, and exercise duration.
Sports that require a strict control of energy con-
sumption, combined with a high-energy expendi-
ture, are of particular concern. In gymnastics of the
highest competitive level, a delay in skeletal mat-
uration was observed, leading to a deterioration of
growth potential in AG, more pronounced for males
than for females, whereas in female RG the genetic
potential for growth was finally achieved by com-
pensation via a late catch-up growth phenomenon.
In all other sports not requiring strict dietary re-
strictions, no deterioration of growth has been
documented.
Intensive physical training and negative energy
balance, by modulating the hypothalamic pituitary
set point at the expected time of puberty, prolong
theprepubertalstageanddelaypubertalprogression
in a variety of sports.
In elite RG and AG, prepubertal stage was pro-
longed and pubertal development was entirely
shifted to a later age, following the bone age
rather than the chronological age and maintain-
ing a normal rate of progression. Female ath-
letespresentawell-documenteddelayedmenarcheal
age, compared to their mothers and nontrained
sisters.
Conflicts of interest
The authors declare no conflicts of interest.
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