This study investigated the impact of physical activity on exam stress levels by measuring cortisol levels in college students who were either sedentary or physically active. Salivary cortisol was collected at baseline, pre-exam, and post-exam time points. Results showed that sedentary students had a significantly larger percent increase in cortisol from baseline to pre-exam compared to active students, supporting the hypothesis that exercise lowers stress responses. However, the differences between groups were smaller than expected, possibly due to limitations like small sample size and lack of control over exam type. Continued research with a larger, more controlled study is warranted.
Applied Kinesiology - Identifying Internal Conditions with the MusclesRandolph Meltzer, D.C.
Randolph Meltzer, D.C., is a respected New York practitioner of chiropractic and naturopathic medicine. Treating a variety of chronic and acute illnesses, Randolph Meltzer, D.C., emphasizes a holistic approach and employs modalities such as homeopathy and applied kinesiology (AK). Also called muscle strength testing, AK relates to the connections between the specific muscles in the body and corresponding glands and organs.
Avis d'expert rédigé par Jérôme Libeskind, consultant, Michel Leclerc, avocat et Arthur Millerand, avocat sur la livraison collaborative. Article publié dans Supply Chain Magazine le 23 septembre 2016
Discriminative Validity of Metabolicand Workload MeasurementAlyciaGold776
Discriminative Validity of Metabolic
and Workload Measurements for
Identifying People With Chronic
Fatigue Syndrome
Christopher R. Snell, Staci R. Stevens, Todd E. Davenport, J. Mark Van Ness
Background. Reduced functional capacity and postexertion fatigue after physical
activity are hallmark symptoms of chronic fatigue syndrome (CFS) and may even
qualify for biomarker status. That these symptoms are often delayed may explain the
equivocal results for clinical cardiopulmonary exercise testing in people with CFS.
Test reproducibility in people who are healthy is well documented. Test reproduc-
ibility may not be achievable in people with CFS because of delayed symptoms.
Objective. The objective of this study was to determine the discriminative validity
of objective measurements obtained during cardiopulmonary exercise testing to
distinguish participants with CFS from participants who did not have a disability but
were sedentary.
Design. A prospective cohort study was conducted.
Methods. Gas exchange data, workloads, and related physiological parameters
were compared in 51 participants with CFS and 10 control participants, all women,
for 2 maximal exercise tests separated by 24 hours.
Results. Multivariate analysis showed no significant differences between control
participants and participants with CFS for test 1. However, for test 2, participants
with CFS achieved significantly lower values for oxygen consumption and workload
at peak exercise and at the ventilatory or anaerobic threshold. Follow-up classification
analysis differentiated between groups with an overall accuracy of 95.1%.
Limitations. Only individuals with CFS who were able to undergo exercise
testing were included in this study. Individuals who were unable to meet the criteria
for maximal effort during both tests, were unable to complete the 2-day protocol, or
displayed overt cardiovascular abnormalities were excluded from the analysis.
Conclusions. The lack of any significant differences between groups for the first
exercise test would appear to support a deconditioning hypothesis for CFS symp-
toms. However, the results from the second test indicated the presence of CFS-related
postexertion fatigue. It might be concluded that a single exercise test is insufficient
to reliably demonstrate functional impairment in people with CFS. A second test
might be necessary to document the atypical recovery response and protracted
fatigue possibly unique to CFS, which can severely limit productivity in the home and
workplace.
C.R. Snell, PhD, Department of
Sport Sciences, University of the
Pacific, Stockton, California, and
Workwell Foundation, Ripon,
California.
S.R. Stevens, MA, Workwell
Foundation.
T.E. Davenport, PT, DPT, OCS,
Department of Physical Therapy,
University of the Pacific, 3601
Pacific Ave, Stockton, CA 95211
(USA), and Workwell Foundation.
Address all correspondence to
Dr Davenport at: [email protected]
pacific.edu.
J.M. Van Ness, PhD, Department
of Sport Scienc ...
Applied Kinesiology - Identifying Internal Conditions with the MusclesRandolph Meltzer, D.C.
Randolph Meltzer, D.C., is a respected New York practitioner of chiropractic and naturopathic medicine. Treating a variety of chronic and acute illnesses, Randolph Meltzer, D.C., emphasizes a holistic approach and employs modalities such as homeopathy and applied kinesiology (AK). Also called muscle strength testing, AK relates to the connections between the specific muscles in the body and corresponding glands and organs.
Avis d'expert rédigé par Jérôme Libeskind, consultant, Michel Leclerc, avocat et Arthur Millerand, avocat sur la livraison collaborative. Article publié dans Supply Chain Magazine le 23 septembre 2016
Discriminative Validity of Metabolicand Workload MeasurementAlyciaGold776
Discriminative Validity of Metabolic
and Workload Measurements for
Identifying People With Chronic
Fatigue Syndrome
Christopher R. Snell, Staci R. Stevens, Todd E. Davenport, J. Mark Van Ness
Background. Reduced functional capacity and postexertion fatigue after physical
activity are hallmark symptoms of chronic fatigue syndrome (CFS) and may even
qualify for biomarker status. That these symptoms are often delayed may explain the
equivocal results for clinical cardiopulmonary exercise testing in people with CFS.
Test reproducibility in people who are healthy is well documented. Test reproduc-
ibility may not be achievable in people with CFS because of delayed symptoms.
Objective. The objective of this study was to determine the discriminative validity
of objective measurements obtained during cardiopulmonary exercise testing to
distinguish participants with CFS from participants who did not have a disability but
were sedentary.
Design. A prospective cohort study was conducted.
Methods. Gas exchange data, workloads, and related physiological parameters
were compared in 51 participants with CFS and 10 control participants, all women,
for 2 maximal exercise tests separated by 24 hours.
Results. Multivariate analysis showed no significant differences between control
participants and participants with CFS for test 1. However, for test 2, participants
with CFS achieved significantly lower values for oxygen consumption and workload
at peak exercise and at the ventilatory or anaerobic threshold. Follow-up classification
analysis differentiated between groups with an overall accuracy of 95.1%.
Limitations. Only individuals with CFS who were able to undergo exercise
testing were included in this study. Individuals who were unable to meet the criteria
for maximal effort during both tests, were unable to complete the 2-day protocol, or
displayed overt cardiovascular abnormalities were excluded from the analysis.
Conclusions. The lack of any significant differences between groups for the first
exercise test would appear to support a deconditioning hypothesis for CFS symp-
toms. However, the results from the second test indicated the presence of CFS-related
postexertion fatigue. It might be concluded that a single exercise test is insufficient
to reliably demonstrate functional impairment in people with CFS. A second test
might be necessary to document the atypical recovery response and protracted
fatigue possibly unique to CFS, which can severely limit productivity in the home and
workplace.
C.R. Snell, PhD, Department of
Sport Sciences, University of the
Pacific, Stockton, California, and
Workwell Foundation, Ripon,
California.
S.R. Stevens, MA, Workwell
Foundation.
T.E. Davenport, PT, DPT, OCS,
Department of Physical Therapy,
University of the Pacific, 3601
Pacific Ave, Stockton, CA 95211
(USA), and Workwell Foundation.
Address all correspondence to
Dr Davenport at: [email protected]
pacific.edu.
J.M. Van Ness, PhD, Department
of Sport Scienc ...
Journal Club: Telomere Length And Cortisol Reactivity In Children Of Depresse...Ashutosh Ratnam
Here's a Journal Club Presentation I made on the article 'Genetic Predisposition to Schizophrenia Associated with Increased Use of Cannabis' which appeared in the Sep 14 issue of Molecular Psychiatry. It examined and found a correlation between shortened telomere length in women and a risk for depression in their daughters.
Undergraduate Research Poster on Stress, Physical Activity and Inflammation in college students. A theoretical model for future research and methods paired with Anthropology Lab Methods course in the Human Biology Lab at UNC CH.
The Study of the Relationship between Flow and Cortisol Release under Stressf...inventionjournals
Flow is an enjoyable experience and occurs when individual fully immersed in an activity. Based on Stress Exchange Model, if individuals evaluate situational challenges as threats and beyond their skill levels, stress will occur. But if the task is assessed as challenge, flow can also be experienced in stressful situations. Flow is between the fatigue and anxiety spectrum. Therefore, when people are experiencing flow, they can also experience moderate arousal. Recent studies have shown a positive relationship between flow and physiological arousal, but no research has been conducted to examine the relationship betweenflow and high arousal in response tostressful situations of team sports yet. Therefore, the aim of the present study is to answer this question: ‘Is flow related to the physiological response of cortisol release in stressful situations of team sports? To this aim, 24 students of physical education were divided into 4 teams, based on their performance level and according to the research purpose, and each team competed with the other three teams. Before and after each competition, salivary cortisol samples of the athletes were taken and at the end of eachcompetition, the athletes completed theflow scale. The collected data has been analyzed by Analysis of Covariance (ANCOVA). The results show that there is an Inverted-U relationship betweenflow andcortisol release, and the average cortisol concentration facilitates the experience of flow, while more or lesscortisol release interferes with the experience of flow. Using the literature of Stress Exchange Model (such asLazarus and Folkman, 1984) and in parallel withCsikszentmihalyi (1990), it can be said that if situational demands are assessed as challenges, they can lead to the flow experience [2]. As a result, flow is associated with the moderate level of arousal that is experienced as a challenge and reminds moderate and positive forms of stress, such as good stress.
This summary focuses on two articles that correlate stress and external factors. The first article by Theodore. B. Vanitallie, (2002) examines the pathology of stress while the research experiment by Bloch, M. (2007) investigates the effect of divorce on stress levels and physiological responses.
The views expressed in the presentations are that of the author and do not necessarily reflect the views of the Government of Canada. Presentations are shared in the original format received from the presenter.
Presentations given at the Conference to Develop a Federal Framework on Lyme Disease are the property of the author, unless otherwise cited. If you reference the author's work, you must give the author credit by naming the author and their work as well as the place and date it was presented.
For more information, contact the Lyme Disease Conference Secretariat at maladie_lyme_disease@phac-aspc.gc.ca
Leukocyte, Leukocyte Subsets, and Inflammatory Cytokine Response to Resistanc...
FInal SUURA paper
1. Measurement of Sedentary vs. Active College Students’ Exam Stress Levels
By Bailey Archer, mentored and funded by Dr. Stephen Luckey
Abstract:
A numberof investigationshave demonstratedthatphysical activity(suchasexercise) positively
impactsa person’s mental andphysical well-being.Moreover,studieshave suggestedthatphysical
activityreducesanindividual’sstressresponse.Investigatorshypothesizethatexercise itself isaphysical
stressorand,therefore,the bodyadaptstoexperiencingstressresultinginareducedresponse toother
stressors.Cortisol isthe primaryhormone releasedbythe bodyinresponse tostress.Althoughcortisol
may have short-termbenefits,chronicelevationof cortisol levelshasbeenlinkedtoanxiety,depression,
emotionchallenge,fear,andhelplessness.Cortisolcaneasilybe measuredinsalivawhichcanprovide
an indicationof the physiologicalstressanindividual isexperiencingduringthe time the sample istaken.
In thisstudy, salivarycortisol levelsinstudentswhoare eitherphysicallyactive (getatleast150 minutes
of moderate torigorousphysical exerciseperweek)orsedentary(little tonoexercise) were takenat
differenttime points.The time pointsincludedabaseline non-stresstime,immediatelypriortoa final
exam,andimmediatelyfollowingafinal exam. Itwashypothesizedthatphysical activity wouldloweran
individual’sresponsetostressand wouldtherefore decrease salivacortisol levelsduringstressful
situations. The dataobtainedprovedthe hypothesistobe correctbecause itdemonstratedthatthe
sedentarystudentshadasignificantlylargerpercentincrease incortisol levelsfromtheirbaseline levels
to justprior tothe examthanthe exercise studentsdemonstrated. Thisfindingbenefitstudentswho
wishto lowertheirstresslevelsaroundexams whichcouldleadtoimprovedacademicperformances.
Introduction:
A numberof investigationshave shownthatphysical exercisehasapositive impacton a
person’s mental andphysical well-being.Moreover,studieshave suggestedthatphysical activity
reducesanindividual’sstressresponse.Investigatorshypothesize thatexercise itself isaphysical
stressorand,therefore,the bodyadaptstoexperiencingstressresultinginareducedresponse toother
stressors2
.
Cortisol isa glucocorticoidreceptormade bythe adrenal cortex and isthe primaryhormone
releasedbythe bodyinresponse tostress. The effectsithasonthe body include,butare notlimitedto,
elevatedbloodpressure,elevatedbloodsugarlevels,andreductionof the body’simmune response.
Althoughcortisol mayhave short-termbenefits,chronicelevation of cortisol levelshasbeenlinkedto
anxiety,depression,emotionchallenge,fear,andhelplessness3
.Chronicincreasedcortisol levelshave
alsobeen showntodecrease memoryrecall4
.Cortisol caneasilybe measuredinsalivawhichcan
provide anindicationof the physiological stressanindividual isexperiencingduringthe time the sample
istaken,howeveritshouldbe notedthatbodilycortisol levelsfluctuate basedontime of day.Cortisol
levelsare generallyhighestbetween2-3hoursthat an individual normallywakesupandgradually
decrease throughoutthe restof the day.Peaksincortisol levelscanoccurdue to stressful situations,
eating,drinking,aswell asduringstrenuousphysical exercise1
.
Methods:
2. Due to the fact thatthe studycontainedhumansubjects,anIRBprotocol wasfirstwrittenand
approvedbefore anytestingwasperformed.Subjectswere thenrecruitedforeachgroup(sedentary
and exercise).Inordertobe consideredasedentaryindividual,participantsmustcomplete lessthan 150
minutesof exerciseperweek. The exerciseindividuals,onthe otherhand,mustcomplete more than
150 minutesof moderate torigorousexercise eachweekwhichisthe WorldHealthOrganization’s
minimumrecommendedamountof weeklyexerciseahealthy individual shouldperformeachweek.
Once the subjectswere recruited,theywererequiredtomaintaintheirstatusof beingsedentaryor
active and logthe exercise performedeachweek.Salivarycortisol levelswereobtainedusingsalivettes
at three differenttime periodsthroughoutthe course of the study.The initial cortisol samplewastaken
duringa non-stressfuldayatthe same time of dayas the individual wouldbe takingtheirfinal examin
the future because cortisol levelsre influencedbytime of day.The secondsample wastakenjustprior
to the individualtakingafinal exam,andthe thirdsample wastakenjustafterthe individual’sfinal exam
was completed.
The salivetteswere thenspundownandthe salivafromeachindividualwasrunintriplicate
usingan LDN Cortisol SalivaELISA. A standardcurve was thengeneratedfromthisELISand the cortisol
levelswere obtainedbycomparingthe wavelengthsobtained fromthe ELISA foreach sample tothis
standardcurve.The cortisol concentrationswerethenaveragedandthe percentincreasesand
decreasedwere calculatedforeachindividual ateachtime pointandcompared.
Data and Results:
Overall,21 studentswere includedinthe studywith5beingstudentathletes,10beingnon-
studentathlete exercisers,and6sedentaryindividuals.Several individualswere thrownoutdue to
beingonbirthcontrol or anxietymedication.Also,one individual wasincludedinthe exercisegroup
whois a studentathlete butwasinjuredatthe beginningof the studyandwas unable todo much
exercise throughoutthe course of the study. The individualwasincludedinthe exercise groupbecause
of the amountof rigorousexercise theirbodywasusedtogoingin to the study,eventhoughthatlevel
of exercise wasn’tcontinuedthroughoutthe time periodinwhichthe cortisol sampleswere taken.
The studentathlete groupdefinitelyhadthe highestaverage numberof minutesof exercise per
week(figure 1),howeverthe percentchangesincortisol levelswereextremelysimilartothose of the
non-studentathlete exercise groupmemberswhoexercisedasmalleramountof time perweek.The
sedentaryindividualshadsome exerciseperweek,butthe exerciseamountdidnotexceedthe amount
necessaryforthemto be consideredinthe exercise group.
The percentdifferences(figure 2) of cortisol levelsforeachgroupof individualsare shownin
figure 2. The crucial sectionof the graphto note are the firstsetof bars showingthe percentincreases
incortisol levelsfromthe baselinetojustpriorto the exam.The difference betweenthe twoaverage
percentincreaseswassignificant,withap-valueof .013. The other twosetsof comparisonsdonotshow
significantdata.
Table 1. Numberof subjectsineachgroup and the
rationof malestofemalesinthe individualgroups.
3. Group # of participants Male to Female Ratio
Athletes 5 2:3
Exercise 10 3:7
Sedentary 6 6 female
Figure 1. demonstratesthe average numberof exerciseinminutesperformedeachweekbyeachgroup
of participants.Standarderrorbarsincluded.
0
100
200
300
400
500
600
700
800
900
1000
Student Athletes Non-Student
Athelete
Exercise
Sedentary
AverageExercise(Minutes)
Average Exercise (minutes) For Each Group
4. Figure 2. The graph showsaverage cortisol concentrationsof all participantsineachgroupwith
standarderror bars. Pvalues:A to B: P=.013, A to C: P>.05, B to C: P>.05.
Discussion:
The data obtainedinthisstudyprovedthe hypothesisthatstudentswhodonotexercise will
have higherpercentincreasesincortisol levelsthanthose studentswhodoexercisetobe correct. The
resultsshowedasignificantdifference inpercentcortisolincreasesfrombaselinetopre-examtime
betweenthe twotestgroupsindicatingthatexercise doesimpactthe body’sstresscortisol responsesin
a positive manner.Thismeansthatstudentswhoexerciseregularlywill have smallerpercentincreases
intheirbodilycortisol levelsgoingintoexamswhichispotentiallyveryimportantbecauseif increased
cortisol levelsaroundexamtime decreasememoryrecall,highercortisol levelswill likelyinhibitthe
student’sabilitytorecall informationneededforthe examandthustheywill notdoas well onthe
exam.
Althoughthe studyyieldedsignificantresultsprovingthe hypothesistobe correct,the data
wasn’texactlyasextreme aswas hoped,meaningthatthe difference betweenexercisersandsedentary
studentswasn’taslarge as it wasinitiallypredictedtobe.There were several crucial limitationstothis
study.Firstof all, the sample size obtainedwasrathersmall,especiallythe numberof sedentary
individualsobtained. Also,ahuge issue wasnot findingenoughindividualsfromthe same class which
meantthat not everyone tookthe same final examandthereforenoteveryonewasintroducedtothe
same amountof stressinthat the OCHEM final examwasprobablyalittle more stressinducingthanthe
philosophyUCORfinal exam. Finally,amajorconcernwiththisstudy wasthat the exercise grouptended
to have lowerstressresponsesoverall,howeveracouple of individuals still hadfairlylarge increasesin
cortisol levels(largerthansome of the sedentarystudents’response increases). A possibleexplanation
0%
100%
200%
300%
400%
500%
600%
Non-Stress to Pre-
Exam
Non-Stress to Post-
Exam
Pre-Exam to Post-
Exam
PercentDifferenceinCortsol
Level
Percent Differences of Cortisol Concentration
Exercise vs. Sedentary
Exercise
5. for thiscouldbe that thiscortisol increase seemslike alot,butmaybe it‘sinfact small comparedto
whatthe increase wouldbe if theyweren’texercisingregularly.
Since there were some clearlimitationstothe study, itwouldbe greatto continue the study
witha much largersample size,all of whom are sedentarytobeginwith.Initial baseline non-stress
samplescouldbe takenandthen the subjectscouldall be introduced tothe same stressorandpre and
poststressorsamples couldbe obtainedlikebefore.Then,these same individualscouldbe put ona
regularworkoutroutine for6 monthsand thenintroducedto a slightly differentstressorinducinga
similarstresslevel andcortisol samplescouldbe takenduringthisstressoraswell.The percent
increasesforeachindividualcouldthenbe analyzed tosee if there were decreasesinthe amount of
stressresponse theyshowedfromwhentheywere sedentarytowhentheywere exercising.
References:
1. Cortisol SalivaELISA." Immunoassaysandservices.LDN.
2. GERBER, M; PÜHSE, U. Do exercise andfitnessprotectagainststress-inducedhealthcomplaints?
A reviewof the literature.ScandinavianJournalof PublicHealth.37,8, 801-819, Nov.2009.
ISSN:14034948.
3. Rimmele,Ulrike,et.Al (2007). TrainedMen Show LowerCortisol,HeartRate,and Psychological
ResponsestoPsychosocial StressComparedwithUntrainedMen. Psychoneuralendocrinology,
32, 628-635.
4. Wolf,O.T.; Convit,Antonio;McHugh,P.F.; Kandil,E.;Thorn,E. L.; De Santi,S.; McEwen,B. S.; de
Leon, M. J. Cortisol differentiallyaffectsmemoryinyoungandelderlymen.Behavioral
Neuroscience,Vol 115(5), Oct 2001, 1002-1011. http://dx.doi.org/10.1037/0735-
7044.115.5.1002Wolf, O. T.; Convit,Antonio;McHugh,P.F.;Kandil,E.;Thorn, E. L.; De Santi,S.;
McEwen,B. S.; de Leon,M. J. Behavioral Neuroscience,Vol 115(5),Oct 2001, 1002-1011.
http://dx.doi.org/10.1037/0735-7044.115.5.1002