Energy Systems and Human Fitness Fitness and training principles
THE HEATH – CARTER ANTHROPOMETRIC SOMATOTYPE
The technique of somatotyping is used to appraise body shape and composition.
It is expressed in a three-number rating representing endomorphy (relative fatness), mesomorphy (relative musculoskeletal robustness) and ectomorphy (relative linearity or slenderness) – always in the same order.
Each component is rated. Ratings of ½ to 2 ½ are considered low, 3 to 5 are moderate, 5 ½ to 7 are high and 7 ½ and above are very high.
For example: a 3-7-1 rating may be that of a weight lifter (high musculature which has tendencies to mesomorph composition) and a swimmer as 2-5-3
Ten anthropometric measurements are needed to calculate the anthropometric somatotype.
Stature (height). Taken against a height scale or stadiometer. Take height with the subject standing straight, against an upright wall or stadiometer, touching the wall with heels, buttocks and back. Orient the head in the Frankfort plane (the upper border of the ear opening and the lower border of the eye socket on a horizontal line), and the heels together. Instruct the subject to stretch upward and to take and hold a full breath. Lower the headboard until it firmly touches the vertex.
Body mass (weight). The subject, wearing minimal clothing, stands in the center of the scale platform. Record weight to the nearest tenth of a kilogram. A correction is made for clothing so that nude weight is used in subsequent calculations.
Skinfolds. Raise a fold of skin and subcutaneous tissue firmly between thumb and forefinger of the left hand and away from the underlying muscle at the marked site. Apply the edge of the plates on the caliper branches 1 cm below the fingers of the left hand and allow them to exert their full pressure before reading at 2 sec the thickness of the fold. Take all skinfolds on the right side of the body. The subject stands relaxed, except for the calf skinfold, which is taken with the subject seated.
Triceps skinfold. With the subject's arm hanging loosely in the anatomical position, raise a fold at the back of the arm at a level halfway on a line connecting the acromion and the olecranon processes.
Subscapular skinfold. Raise the subscapular skinfold on a line from the inferior angle of the scapula in a direction that is obliquely downwards and laterally at 45 degrees.
Supraspinale skinfold. Raise the fold 5-7 cm (depending on the size of the subject) above the anterior superior iliac spine on a line to the anterior axillary border and on a diagonal line going downwards and medially at 45 degrees. (This skinfold was formerly called suprailiac, or anterior suprailiac. The name has been changed to distinguish it from other skinfolds called "suprailiac", but taken at different locations.)
Medial calf skinfold. Raise a vertical skinfold on the medial side of the leg, at the level of the maximum girth of the calf.
Biepicondylar breadth of the humerus, right. The width between the medial and lateral epicondyles of the humerus, with the shoulder and elbow flexed to 90 degrees. Apply the caliper at an angle approximately bisecting the angle of the elbow. Place firm pressure on the crossbars in order to compress the subcutaneous tissue.
Biepicondylar breadth of the femur, right. Seat the subject with knee bent at a right angle. Measure the greatest distance between the lateral and medial epicondyles of the femur with firm pressure on the crossbars in order to compress the subcutaneous tissue.
Upper arm girth, elbow flexed and tensed, right. The subject flexes the shoulder to 90 degrees and the elbow to 45 degrees, clenches the hand, and maximally contracts the elbow flexors and extensors. Take the measurement at the greatest girth of the arm.
Calf girth, right. The subject stands with feet slightly apart. Place the tape around the calf and measure the maximum circumference.
From these measurements you can calculate the anthropometric somatotype by
Entering the data onto a somatotype form
Entering the data into equations derived from the rating form
SUITABILITY OF PHYSIQUE
Triathletes are more muscular than runners but with less leg development than cyclists and less upper body development than swimmers. Low body weight improves the power-to-weight ratio.
Short legs boost balance and stability, allowing players to pivot. They also can prevent back injuries. Speed and aerobic endurance are musts.
Long arms and legs act as levers, allowing swimmers to produce greater force in the water. Like flippers, big hands and feet propel the swimmer faster.
Light frames and low body fat levels conserve energy because the runner carries less weight. Muscles will ideally be slow twitch (or fatigue resistant), aiding endurance
Above average height allows a high release position, which adds distance to throws. A strong, heavy body boosts the throwers momentum. Must be muscular in upper and lower body but can carry a little fat.
All over muscle and lower body fat levels give sprinters their explosive powers. Muscles must be fast twitch, meaning they contract quickly. Height does not matter, so long as stride length is efficient.
For mid court players, powerful legs enable leaps to intercept high passes and sprint speed to chase the ball. End court players are usually in the top 10 percent, with long arms for shooting and defending.
Short legs lower the weight lifters centre of gravity (CoG), improving stability. Short arms reduce the arc through which the weight must be lifted. A stocky, thick set adds power, but also stabilises and protects the joints.
Long limbs in relation to the body boost the gymnasts power-to-ratio. Low body fat results in better muscle definition. Broad shoulders and narrow hips promote maximum upper body strength. Small compact gymnasts use less energy in difficult training regimes
BODY TYPES SOMATOTYPE Endomorph
Oval-shaped person with concentration of weight in the centre of the body, abdominal sag, flabby limbs and poorly toned muscles.
Prone to being fat because of a good food absorption system but too efficient storage (fats) system
BODY TYPES SOMATOTYPE Mesomorph
Big-chested person endowed with dense muscle and huge, strong bones. Although the body mass is well proportioned, this body type has a tendency to accumulate adipose tissue in later adult years, particularly if inactive.
Prone to muscularity.
BODY TYPES SOMATOTYPE Ectomorph
Extreme thinness, protruding neck, sunken chest, round shoulders, undersized musculature and a fragile skeletal system.
Thin because of a poor food assimilation (protein coupling causing overheating and loss of energy due to this) system.
Everyone has some part of each of the three types, but those high in endomorphic characteristics must regulate caloric intake to avoid overweight.
MAN evolved from quadrupedal to bipedal through adaptations of the musculoskeletal system over millions of years.
FOUR LEGGED ANIMALS have a skeletal system similar in shape to a bridge. They have an arched backbone to support internal structures.
THROUGH EVOLUTION: Changes to an upright posture
Vertebrae adapted to the vertical weight bearing stress, thus the vertebral arch evolved to an “S” shape.
There became more burden on the pelvis , thus the shape of the pelvis changed to be able to support the weight of the upper body.
The foot changed shape to permit bending and twisting movements of the spine. The feet were required more for weight bearing and less for grasping and so the toes shortened. The arch of the foot had to bear more stress under the body weight.
The individual vertebrae changed shape to permit bending and twisting movements of the spine. This change in shape has actually weakened the vertebral column, particularly in the lumbar region where herniated discs are common due to stress.
STATIC AND DYNAMIC POSTURE
STATIC posture is when a person is in equilibrium or motionless.
DYNAMIC posture is when an individual is in motion.
Definition: A state of muscular and skeletal balance, which protects the supporting structures of the body against progressive deformity or injury.
Advantages: Mechanically functional and economical.
WHY GOOD POSTURE?
Allows internal organs to be supported well.
Gives impression of enthusiasm, confidence and initiative.
CENTRE OF GRAVITY
The center of gravity is the point through which gravity acts. It passes between the hips and forward of the sacrum.
WE MAINTAIN BALANCE BY?
Eyes – visual cues
Middle Ear – equilibrium
Receptors in our joints and muscles
WHEN ARE WE MOST STABLE?
We are most stable in the sitting position because we have a wide base of support and a lowered Centre of gravity
We are least stable whilst standing because we have a small base of support and a raised Centre of gravity.
GRAVITY pulls on bones and joints. Therefore:
With a well aligned body, the bones take pressure of resisting gravity and muscles maintain correct alignment.
With a poorly aligned body, the muscles and ligaments bear the strain of the effects of gravity. The muscles are unbalanced and strained which leads to postural deviations.
STRUCTURE is related to FUNCTION:
Functional deviations due to soft tissue response to exercise can become structural deviations, which result in permanent changes in bone shape. This requires surgery or some other medical intervention (e.g. leg braces) to correct.
Definition: The faulty relationship of the various segments of the body, producing increased stress on the supporting structures.
Poor posture makes it more difficult to maintain efficient balance over the base of support and causes sagging, which will permanently stretch muscle groups.
WHAT CAUSES POOR POSTURE?
Poor standing, sitting, walking
Poor nutrition (e.g. rickets causes bow legs)
Lack of exercise (muscle atrophy – waste)
Clothing – high heeled shoes cause lordosis
Poorly designed furniture – shape of chairs to promote good sitting posture
Specific sports – gymnastics (lordosis); breastroke (round shoulders)
Emotional/Self esteem Factors – hunch shoulders
Symptoms of poor posture can include:
Bent knees when standing or walking
Head that either leans forward or backward
Body aches and pains
MUSCLES AND POSTURE YOU NEED TO WORK THESE MUSCLES TO MAINTAIN CORRECT POSTURE YOU NEED TO STRETCH THESE TO MAINTAIN CORRECT POSTURE Tibialis anterior Gastrocnemius, Soleus Quadraceps Hamstrings Gluteals Ilio Psoas Abdominals Erector Spinae Trapezius Pectorals, Latissimus Dorsi MUSCLES RESISTING GRAVITY MUSCLES ASSISTING GRAVITY
Poor posture interferes with a number of the body's postural mechanisms, including:
Slow-twitch and fast-twitch muscle fibres
Muscle strength and length
Nervous system feedback on the body's position in space.
Slow-twitch and fast-twitch muscle fibres
Skeletal muscle is made up of two types of muscle fibre - slow-twitch and fast-twitch. Generally, slow-twitch muscle fibres are found in the deeper muscle layers. They help us to maintain posture without too much effort, and contribute to balance by 'sensing' our position and relaying this information to the brain. Fast-twitch muscle fibres are used for movement and activity. Slow-twitch fibres burn energy slowly and can keep working for a long time without tiring. However, fast-twitch fibres quickly run out of steam. Poor posture causes muscle fatigue because it calls on the fast-twitch fibres instead of slow-twitch fibres to maintain the body's position.
Muscle strength and length
Over time, poor posture that demands support from fast-twitch fibres causes the deeper supporting muscles to waste away from lack of use. Weak, unused muscles tend to tighten, and this shortening of muscle length can compact the bones of the spine (vertebrae) and worsen posture.
Nervous system feedback on the body's position in space
The deeper layers of muscle are concerned with 'sensing' our position in space and relaying this information to the brain. If this function is taken over by muscles that mainly contain fast-twitch fibres, the brain gets an incomplete picture. The brain assumes that the body needs to be propped up to counteract the effects of gravity, so it triggers further muscle contraction. This adds to the general fatigue and pain felt by the person with poor posture.
Listen to your body
Good posture feels effortless, which is why traditional 'good posture' suggestions like throwing your shoulders back and sticking out your chest may feel uncomfortable too. Instead, listen to your body. Make minor adjustments while standing and sitting. Which position feels the easiest and most graceful? In most cases, concentrating on other tasks (such as work) can direct attention away from any feelings of physical discomfort. Get into the habit of regularly tuning in to your body. If you feel muscle tension or fatigue, move into another position.
POSTURE AND SOMATOTYPE
ECTOMORPHS: have more postural deformities than other groups and are related to the vertebral column e.g. poked head, round shoulders, kyphosis, lordosis, scoliosis.
ENDOMORPHS: suffer mainly from leg deformities, due to the added burden of extra weight e.g. knock knees, flat feet, duck feet
MESOMORPHS: tend to be free from postural defects.
CAUSES OF POSTURAL DEFECTS Mental attitude Wearing high heals Other causes Mostly seen in the lower limbs e.g. in extreme cases would result in scoliosis. Skeletal Imbalance Acquired by repeating the same body alignment e.g. leaning over a desk, slouching in a chair. When body segments are held out of alignment for extended period of time the surrounding muscles rest in a lengthened or shortened position. Habit Weakens bones and muscles and causes joints to lose their strength e.g. arthritis, osteoporosis. Disease Weakens the support normally provided to the total framework. Injury RESULT CAUSE
POSTURAL DEFECTS Caused by the pelvis tilting too far forward (anterior pelvic tilt – APT). Abdominal muscles become stretched and weakened. Correction - stretch erector spinae and hip flexors - strengthen thigh extensors and abdominals LORDOSIS (hollow back) Increases the curve in the thoracic region. Correction - stretch the upper anterior thoracic region - strengthen the muscles of the posterior thoracic region. KYPHOSIS (round-back, Sheuermannis disease) Due to a weakened trapezius and rhomboid muscles Correction - stretch anterior thoracic muscles of the upper body - strengthen adductor muscles of the scapula ROUND SHOULDERS Neck is slightly flexed Head is partially tilted forward Associated with round shoulders (abducted scapula) Correction - stretch anterior neck muscles - strengthen posterior muscles POKED HEAD ANTERIOR/POSTERIOR POSITION EXPLANATION/CAUSE/CORRECTION DEFECT
Lateral curvature of the spine
In severe cases also causes longitudinal rotation of the vertebrae
Caused by uneven leg lengths, muscle imbalance and ligament lengthening
Begins with an e-shaped curve = functional scoliosis
Correction - for functional scoliosis:
Use orthotic device in shoe which increases leg length
Internal rotation at the hip joint leading to inward knee rotation leading to inverted feet.
Correction - stretch medial rotators of the hip joint
strengthen lateral rotators of the hip joint
Inverted feet “ Pigeon Toes” Genetic Needs medical attention early in life Correction - general strengthening exercises for leg muscles Bow Legs and Knock Knees
DESIRABLE POSTURES FOR HIGH LEVEL SPORT PERFORMANCE
APT, protruding buttocks, “overhanging knee”.
Reasonable spinal curvature
Inverted feet promotes fast steps and good balance.
Reasonable degree of spinal curvature
Inverted feet to promote quick stepping
APT, protruding buttocks and “overhanging knee” for players who need bursts of speed.
Characteristics are thought to relate to heavy training rather than predisposed bone shape.
Cyclists have slightly rounded backs and “overhanging knee”.
“ overhanging knee” is due to the heavy musculature in the thighs and buttocks.
Athletes with APT and protruding buttocks are excellent sprinters.
Common in Africans and European females.
Athletes who also have “overhanging knee” where the patella is forward of the ankle joint have an advantage in sprinting.
Female gymnasts with lordosis and APT are able to hyperextend their spine more easily.
People with inverted feet are suited to backstroke, freestyle and butterfly.
People with everted feet (duck feet) are suited to breastroke.
Inverted feet (pigeon toes) results in a speed advantage over a short distance because they have to take short steps.
Racquet Sports DESIRABLE POSTURE SPORT
IMPROVE YOUR GENERAL POSTURE
Remember the rule of 'curve reversal' - for example, if you've been leaning over your desk, stretch back the other way.
Perform stretching exercises two or three times per week to boost muscle flexibility.
Exercise regularly to improve muscle strength and tone.
Stretch your neck muscles regularly by turning your head from one side to another.
Your abdominal muscles support your lower back, so make sure they are in good condition. Do 'abdominal crunches' (lie on your back and curl your ribcage and pelvis as close together as possible) rather than straight-backed sit-ups (which exercise the muscles of the hips and thighs).
Avoid standing on one foot for long periods of time.
Cross your legs at the ankle, rather than the knee.
Avoid sitting in soft, squashy chairs.
Use lumbar rolls to support your lower back when sitting in regular chairs or driving the car.
Switch to ergonomic chairs in the office, or for any activity that requires you to sit for long periods of time.
Make sure your mattress is supportive enough to keep your spine straight when lying on your side.
Use a pillow that supports your neck.
Keep your back straight and use your thigh muscles when lifting heavy weights.
THINGS TO REMEMBER
The complications of poor posture include back pain, spinal dysfunction, joint degeneration, rounded shoulders and a potbelly.
Suggestions to improve your posture include regular exercise and stretching, ergonomic furniture, and paying attention to the way your body feels.