Developmental Issues in Developmental Issues in Exercise ScienceExercise Science
Physical Responses on Exercise Physical Responses on Exercise Conditioning in AdolescenceConditioning in Adolescence
Developmental ContinuumDevelopmental ContinuumPrenatalPrenatal– EmbryoEmbryo 2-8 weeks2-8 weeks– FetusFetus 8weeks-birth8weeks-birth
NeonateNeonate birth-4 weeksbirth-4 weeks
InfancyInfancy– EarlyEarly birth-12 monthsbirth-12 months– LaterLater 12-24 months12-24 months
ChildhoodChildhood– ToddlerhoodToddlerhood 24-36 months24-36 months– Early Childhood (Preschool)Early Childhood (Preschool) 3-5 yrs3-5 yrs– Late ChildhoodLate Childhood 6-10 yrs6-10 yrs
AdolescenceAdolescence– Pre-pubescencePre-pubescence
FemalesFemales 10-12 yrs10-12 yrsMalesMales 11-13 yrs11-13 yrs
– Post-pubescencePost-pubescenceFemalesFemales 12-18 yrs12-18 yrsMalesMales 14-20 yrs14-20 yrs
AdulthoodAdulthood– Young adulthoodYoung adulthood 18-40 yrs18-40 yrs– Middle adulthoodMiddle adulthood 40-60 yrs40-60 yrs– Older adulthoodOlder adulthood
Young oldYoung old 60-70 yrs60-70 yrsMiddle oldMiddle old 70-80 yrs70-80 yrsFrail oldFrail old 8080++ yrs yrs
Motor DevelopmentMotor Development
Described as “Progressive change in Motor Described as “Progressive change in Motor behavior throughout the life cycle”behavior throughout the life cycle”
1.1. Physical ChangesPhysical Changes
2.2. Biomechanical ChangesBiomechanical Changes
Developmental Changes in Youth Developmental Changes in Youth FitnessFitness
Female 9-11, Male 11-13 children’s bodies Female 9-11, Male 11-13 children’s bodies begin to changes due to hormonal change with begin to changes due to hormonal change with pubertypubertyThese change influence by health-related These change influence by health-related physical fitnessphysical fitness– Muscular strength/enduranceMuscular strength/endurance– Aerobic enduranceAerobic endurance– Joint flexibilityJoint flexibility– Body compositionBody composition
Field based researchField based research– Know about the motor performance of youth is Know about the motor performance of youth is
derivedderived– Conducted in school, play grounds…Conducted in school, play grounds…– Realistic motor performance situations Realistic motor performance situations – More relaxed atmosphere than a formal LabMore relaxed atmosphere than a formal Lab
Muscular Strength and EnduranceMuscular Strength and Endurance
Key components of Health-related physical Key components of Health-related physical fitness.fitness.Measurement: bent knee sits-ups, hand grip…Measurement: bent knee sits-ups, hand grip…Pre-pubertal growth spurt, girls and boys Pre-pubertal growth spurt, girls and boys follow a same pattern until male growth spurt.follow a same pattern until male growth spurt.Obvious gender differences are muscle mass Obvious gender differences are muscle mass increases of maleincreases of male
Aerobic EnduranceAerobic EnduranceCan use treadmill test to measure maximal; oxCan use treadmill test to measure maximal; oxygen capacity in childrenygen capacity in children
Lab tests Lab tests v.s.v.s. Field tests Field tests
Female improve their running time until 14 yrs Female improve their running time until 14 yrs of ageof age
Male show improvement across age groups untMale show improvement across age groups until age 16il age 16
Can be due to increase muscle mass in male anCan be due to increase muscle mass in male and limit physical activity as acquisition of a drivd limit physical activity as acquisition of a driver license in femaleer license in female
Exercise Scientist’s InterestsExercise Scientist’s Interests
Biomechanist: an increase length accompanyiBiomechanist: an increase length accompanying growing bodiesng growing bodies
Physiologist:an increase in body fat on the perfPhysiologist:an increase in body fat on the performance of a prepubescent girlormance of a prepubescent girl
Joint FlexibilityJoint Flexibility
Sit and reach is the test most use in determine Sit and reach is the test most use in determine flexibilityflexibility
Generally increases until about age of 16Generally increases until about age of 16
A reduction in joint flexibility may occur until A reduction in joint flexibility may occur until the muscles and tendons growththe muscles and tendons growth
Body CompositionBody Composition
From age of 10 to 15 yrs, females experience From age of 10 to 15 yrs, females experience an increase in body fatan increase in body fatMale undergo an increase in muscle mass and Male undergo an increase in muscle mass and consistent body fat percentageconsistent body fat percentageMay throughout adolescence and subject to May throughout adolescence and subject to lifestyle behaviors as physical activity levels lifestyle behaviors as physical activity levels and nutritional patternsand nutritional patternsCan help researchers establishing weight Can help researchers establishing weight reduction strategies and so on.reduction strategies and so on.
Youth SportsYouth Sports
American children in 1999 are 13 pound American children in 1999 are 13 pound heavier than same age group were in 1983heavier than same age group were in 1983
10 yrs old required longer time to run a mile in 10 yrs old required longer time to run a mile in 1989 than those measure in 19801989 than those measure in 1980
Modern children may be fatter, less fit, more Modern children may be fatter, less fit, more susceptible to chronic diseasesusceptible to chronic disease
School system tried to solve budgetary School system tried to solve budgetary problem by decreasing physical education problem by decreasing physical education classes of eliminating them entirelyclasses of eliminating them entirely
After school youth sport program like After school youth sport program like community soccer and Little League baseballcommunity soccer and Little League baseball
Those program can serve to develop skills for Those program can serve to develop skills for enjoyable fitness activities enjoyable fitness activities
Considerations of Athletic Training Considerations of Athletic Training
Training principles and injury susceptibility Training principles and injury susceptibility and preventionand prevention
SpeedSpeed
While pre-puberty, boy’s and girl’s are similar While pre-puberty, boy’s and girl’s are similar in their average running velocity and pattern of in their average running velocity and pattern of speed improvementspeed improvement
While pubertal change begin, male continue tWhile pubertal change begin, male continue to improve in speed and female begin to plateao improve in speed and female begin to plateauu
Muscular strength is a major component of runMuscular strength is a major component of running speeds in male ning speeds in male
Girl tends to plateau in speed at about age 11 Girl tends to plateau in speed at about age 11 and may due to puberty-related gain in body and may due to puberty-related gain in body fatfat
Speed also largely related to genetically Speed also largely related to genetically determined muscle fibers type of young determined muscle fibers type of young athletes, but improved with trainingathletes, but improved with training
Muscular PowerMuscular Power
The result of a forceful muscular contraction The result of a forceful muscular contraction performed rapidlyperformed rapidly
Most adolescents participate require muscular Most adolescents participate require muscular power to successful skill performancepower to successful skill performance
Performance patterns are similar to the patterns Performance patterns are similar to the patterns observed in other fitness characteristicsobserved in other fitness characteristics
Increases in muscle mass in male and body fat Increases in muscle mass in male and body fat in female are major contributors to the in female are major contributors to the performance patterns following the onset of performance patterns following the onset of pubertypuberty
Muscle power is highly individual’s Muscle power is highly individual’s genetically determined muscle fiber genetically determined muscle fiber characteristics characteristics
Scientist may help determine an athlete’s Scientist may help determine an athlete’s potential in a power-oriented skillspotential in a power-oriented skills
Measurement of musculMeasurement of muscular power have a skill coar power have a skill component that may reducmponent that may reduce their validitye their validity
Reaction TimeReaction Time
Time interval from the onset of a signal to the Time interval from the onset of a signal to the initiation of the appropriate movement initiation of the appropriate movement responseresponse
Ability to process movement-oriented Ability to process movement-oriented information rapidlyinformation rapidly
Can improve their reaction time throughout Can improve their reaction time throughout adolescence and then begin to plateauadolescence and then begin to plateau
Factors Influence Reaction TimeFactors Influence Reaction Time
The familiarity of the The familiarity of the skill to be performedskill to be performed
The opportunity to The opportunity to practice the required practice the required skillskill
The number of The number of movement choices from movement choices from which the performer which the performer must selectmust select
Intensive Training and Health Intensive Training and Health Considerations for the Young Considerations for the Young
AthletesAthletes
High-intensity Training ConsiderationsHigh-intensity Training Considerations
Children are not miniature adultsChildren are not miniature adults
Young athletes differ from adult athletesYoung athletes differ from adult athletes– Cognitively: conceptualize and strategize in sport Cognitively: conceptualize and strategize in sport
situationssituations– Psychologically: motivated differ from parents and Psychologically: motivated differ from parents and
coachcoach– Physically:Physically:– Physiologically: immature bodies response to Physiologically: immature bodies response to
intense trainingintense training
Degree o f Skeletal MaturityDegree o f Skeletal MaturityBone growth take place at the epiphyseal growBone growth take place at the epiphyseal growth plateth plateExcessive weight bearing or shearing forces caExcessive weight bearing or shearing forces can result in fractures of the platen result in fractures of the plateA reduction in blood flow to the growing bone A reduction in blood flow to the growing bone and subsequent premature cessation of bone grand subsequent premature cessation of bone growth owth Growth plate remain a concern for prepubesceGrowth plate remain a concern for prepubescent and adolescent population until the ages of 1nt and adolescent population until the ages of 18 to 20 yrs.8 to 20 yrs.
Overuse injuries due to the repeated Overuse injuries due to the repeated application of many small stresses that by application of many small stresses that by themselves create no apparent injury as stress themselves create no apparent injury as stress fractures and tendinitisfractures and tendinitis
May have originated before an athlete reached May have originated before an athlete reached puberty but cumulative effect may reveal until puberty but cumulative effect may reveal until adolescenceadolescence
Thermoregulation in the Young AthleteThermoregulation in the Young Athlete
Children loss heat rapidly, due to small body Children loss heat rapidly, due to small body surface area to mass ratiosurface area to mass ratioChildren tend to perspire less than adultsChildren tend to perspire less than adultsWhen training in warm or hot temp.When training in warm or hot temp.– Training lighter than normalTraining lighter than normal– Session should shorter than normalSession should shorter than normal– Frequent rest in the shadeFrequent rest in the shade– Drink fluids before thirst levelsDrink fluids before thirst levels– Training time and intensity should be increased Training time and intensity should be increased
gradually until athlete become acclimatedgradually until athlete become acclimated
When training in cool or cold temp.When training in cool or cold temp.– Out of water when not training or competingOut of water when not training or competing– When water below 22 , stay in the water a ℃When water below 22 , stay in the water a ℃
maximum of 15 min maximum of 15 min
Exercise scientist need to educate about Exercise scientist need to educate about developmental differences in thermoregulation developmental differences in thermoregulation and take step to prevent the athlete’s healthand take step to prevent the athlete’s health
Nutritional ConcernsNutritional Concerns
Growing bodies of young athletes require a Growing bodies of young athletes require a healthy diethealthy dietExcessive caloric restrictions can result in loss Excessive caloric restrictions can result in loss of bone mineral densityof bone mineral densityYoung athletes have either intrinsic or Young athletes have either intrinsic or extrinsic pressure to obtain a leaner body build extrinsic pressure to obtain a leaner body build may attempt rapid weight loss by unhealthy may attempt rapid weight loss by unhealthy behaviorsbehaviorsYo-Yo dieting as gain weight after meet and Yo-Yo dieting as gain weight after meet and loss before meetloss before meet
Resistance Training with the Resistance Training with the Prepubescent AthletePrepubescent Athlete
Two concernsTwo concerns
1.1. Potential damagePotential damage of epiphyseal plate as a r of epiphyseal plate as a result of excessive weight bearing on growiesult of excessive weight bearing on growing bonesng bones
2.2. Prepubescent resistance training is its Prepubescent resistance training is its efficefficacyacy
Safety Guidelines for Prepubescent Safety Guidelines for Prepubescent Strength Training ProgramStrength Training Program
Neural EfficacyNeural Efficacy
Levels of testosterone are need for muscle hypLevels of testosterone are need for muscle hypertrophy to occur and then strength increaseertrophy to occur and then strength increase
Short-term weight training in prepubescents reShort-term weight training in prepubescents reveal a strength gains occur without changes in veal a strength gains occur without changes in muscle size without hypertrophy may concern muscle size without hypertrophy may concern neural efficiencyneural efficiency
Adult Development and AgingAdult Development and Aging
Aging is the accumulation of changes in a Aging is the accumulation of changes in a person over timeperson over time– Juvenile [via infancy, childhood, preadolescence, Juvenile [via infancy, childhood, preadolescence,
adolescence (teenager)]: 0-19adolescence (teenager)]: 0-19– Early adulthood: 20-39Early adulthood: 20-39– Adulthood (20 to 40 yrs)Adulthood (20 to 40 yrs)– Middle adulthood (40-60 yrs)Middle adulthood (40-60 yrs)– Old adulthood (60Old adulthood (60++ yrs) yrs)
The Demographics of AgingThe Demographics of Aging
Many factor Many factor contributing to this contributing to this trend toward a greater trend toward a greater proportion of older proportion of older adultsadults– Health careHealth care
– Proper dietProper diet
– Physical activityPhysical activity
– Smoking Smoking
The Physiology of AgingThe Physiology of AgingAging in humans refers to a multidimensional Aging in humans refers to a multidimensional process of physical, psychological, and social process of physical, psychological, and social changechange
Understanding the effects aging has on specifiUnderstanding the effects aging has on specific physiologic systems assists the professional c physiologic systems assists the professional working upon principles of working upon principles of – Task specificityTask specificity– Interindividual / intraindividual variabilityInterindividual / intraindividual variability
Nervous and muscular systems are of particulNervous and muscular systems are of particular importance when motor performance of oldar importance when motor performance of older adults is examineder adults is examined
Muscle in AgingMuscle in Aging
With increasing ageWith increasing age– Slow-twitch fiber increaseSlow-twitch fiber increase– Fast-twitch fiber decreaseFast-twitch fiber decrease– May represent a model of disuseMay represent a model of disuse– Total muscle size and muscle strength decreaseTotal muscle size and muscle strength decrease
Can be test by measuring tape and MRICan be test by measuring tape and MRI
– The relationship between muscle size and muscle The relationship between muscle size and muscle strength is not perfect in older adultsstrength is not perfect in older adults
The Central Nervous SystemThe Central Nervous SystemSome evidence that the number of brain cells Some evidence that the number of brain cells decreases with advancing agedecreases with advancing age
The numbers of connections or synapses The numbers of connections or synapses between brain neurons decrease with agebetween brain neurons decrease with age
Motor behavior in older adult may be altered Motor behavior in older adult may be altered because of deteriorated neural pathwaysbecause of deteriorated neural pathways
Aging brain also susceptible to the reception Aging brain also susceptible to the reception of an inadequate amount of oxygen, hypoxiaof an inadequate amount of oxygen, hypoxia– The nerve cells’ function and longevity are The nerve cells’ function and longevity are
affectedaffected
Reaction time and AgingReaction time and Aging
The ability of react quickly to certain The ability of react quickly to certain situations may diminishedsituations may diminishedRT demonstrate a tendency to ward slowing RT demonstrate a tendency to ward slowing with age.with age.Age-related structural changes in the brain are Age-related structural changes in the brain are inevitable, older adults can moderate the inevitable, older adults can moderate the influence of aging on brain functioninfluence of aging on brain function– Physical activityPhysical activity
Maintenance or enhancement RT ability in older adult Maintenance or enhancement RT ability in older adult may stem from an increase in cerebral blood flow and may stem from an increase in cerebral blood flow and increase oxygen to brain cellincrease oxygen to brain cell
BalanceBalance
Involves many variables (vestibular system, soInvolves many variables (vestibular system, somatosnesory system…)that interacts to control matosnesory system…)that interacts to control an individual’s posture and prevent fallsan individual’s posture and prevent falls
Seniors may use different methods to recover fSeniors may use different methods to recover from loss of balance (older adults tend to activarom loss of balance (older adults tend to activate muscle groups of the lower body of a differete muscle groups of the lower body of a different pattern) nt pattern)
Compensatory mechanism to prevent fallsCompensatory mechanism to prevent falls– Environmental considerationsEnvironmental considerations
Firm surface underfootFirm surface underfoot
Improving room lightingImproving room lighting
– Muscle fitnessMuscle fitnessIncreasing the muscular strength of the ankle, knee, and Increasing the muscular strength of the ankle, knee, and hiphip
Skeletal SystemSkeletal System
Following skeletal maturity, age-related changes in bFollowing skeletal maturity, age-related changes in bone characteristics are generally not noticeable until one characteristics are generally not noticeable until old adulthoodold adulthoodIn older adults, reduction in the water content of interIn older adults, reduction in the water content of intervertebral discs, spinal misalignment, and loss of bone vertebral discs, spinal misalignment, and loss of bone mineral densitymineral densityLoss of water in the discs of the spinal column, reducLoss of water in the discs of the spinal column, reduces their shock absorption and capacities, and discs coes their shock absorption and capacities, and discs compression may reduces the length of spinal columnmpression may reduces the length of spinal column
OsteoporosisOsteoporosisBone mineral production and absorptioBone mineral production and absorption are ongoing processesn are ongoing processesWhen absorption becomes more acceleWhen absorption becomes more accelerated than what is accounted for by the rated than what is accounted for by the normal aging, it is known as osteoporonormal aging, it is known as osteoporosissisTwo major concerns become apparentTwo major concerns become apparent– Brittle bones may experience fracturBrittle bones may experience fractur
es form withines form withinUsual seen in vertebae of the spinUsual seen in vertebae of the spinal columnal column
– The potential for bone fractures follThe potential for bone fractures following event minimal traumaowing event minimal trauma
Sensory SystemsSensory Systems
Visual systemVisual system– Many changes adversely affect the quality of Many changes adversely affect the quality of
vision (fig.)vision (fig.)– Functional changesFunctional changes
Decrease in visual clarityDecrease in visual clarity
Reduction in the constricting and dilating properties of Reduction in the constricting and dilating properties of the eye musclethe eye muscle
Decline I n the ability to adapt to dim light settingsDecline I n the ability to adapt to dim light settings
– ImprovementImprovementSurgical procedure for cataractsSurgical procedure for cataracts
Increasing room illuminationIncreasing room illumination
Wearing corrective eye wearWearing corrective eye wear
Auditory SystemAuditory System– Presbycusis, or age-related hearing loss, is the cumPresbycusis, or age-related hearing loss, is the cum
ulative effect of aging on hearing. Also known as pulative effect of aging on hearing. Also known as presbyacusis, it is defined as a progressive bilateral resbyacusis, it is defined as a progressive bilateral symmetrical age-related sensorineural hearing loss symmetrical age-related sensorineural hearing loss (fig.)(fig.)
– Can be result from a loss of nerve cells in the inner Can be result from a loss of nerve cells in the inner ear, a decreased in the flexibility of the bones and ear, a decreased in the flexibility of the bones and membranes of the middle ear, and the increased semembranes of the middle ear, and the increased secretion of cerumen (earwax)cretion of cerumen (earwax)
– Older adults experience tinnitus, which is a constaOlder adults experience tinnitus, which is a constant ringing or buzzing noise in the earsnt ringing or buzzing noise in the ears
Longitudinal Versus Cross-Sectional Aging Longitudinal Versus Cross-Sectional Aging researchresearch– Longitudinal research involves observation of the Longitudinal research involves observation of the
dame individuals for an extended duration dame individuals for an extended duration – Cross-Sectional research might study a group with Cross-Sectional research might study a group with
similar similar aged aged
GeneticsGenetics
Lifetime physical activityLifetime physical activity
Nutritional historyNutritional history
General socioeconomicGeneral socioeconomic
Medical backgroundMedical background
Intervention Strategies Intervention Strategies
Compensatory techniques for offsetting these aCompensatory techniques for offsetting these age-related declined using principles of task spege-related declined using principles of task specificity, interindividual and intraindividual varicificity, interindividual and intraindividual variabilitiesabilities
Altering environmental conditionsAltering environmental conditions
Use medical advancesUse medical advances
Increasing muscular strengthIncreasing muscular strength
Practice postural stability taskPractice postural stability task
Risk Factors for Falling and Possible Risk Factors for Falling and Possible Intervention StrategiesIntervention Strategies
Possible Risk FactorsPossible Risk Factors
Of the Older AdultOf the Older Adult
Possible Intervention StrategiesPossible Intervention Strategies
Decrease in muscular strengthDecrease in muscular strength Strength training exerciseStrength training exercise
Assistance device (cones, walkers, handrails)Assistance device (cones, walkers, handrails)
Decrease in joint flexibilityDecrease in joint flexibility Active lifestylesActive lifestyles
Stretching exerciseStretching exercise
Decrease in visual abilitiesDecrease in visual abilities Increased room lightingIncreased room lighting
Reduced glareReduced glare
Eye glassesEye glasses
Surgical treatmentSurgical treatment
Decrease in auditory abilitiesDecrease in auditory abilities Removal of cerumenRemoval of cerumen
Hearing assistance devicesHearing assistance devices
Decrease in proprioceptionDecrease in proprioception Firm walking surfaceFirm walking surface
Focused attention on taskFocused attention on task
Allowance for practice of taskAllowance for practice of task
Increased motivationIncreased motivation
MedicineMedicine Awareness of drug side effectsAwareness of drug side effects
Awareness of drug interaction side effectsAwareness of drug interaction side effects
Adapted from Gallahue & Ozmun, 1995Adapted from Gallahue & Ozmun, 1995
Elite Motor Performance in Older Elite Motor Performance in Older AdulthoodAdulthood
Gerontology is the scientific study of Gerontology is the scientific study of the aging processthe aging processChronologic age v.s. biologic ageChronologic age v.s. biologic ageMotor performance in adulthood is hiMotor performance in adulthood is highly variableghly variableSome older individuals may be come Some older individuals may be come to frail and suffer serious health probto frail and suffer serious health problems at a early older agelems at a early older ageContinue to excel in their performancContinue to excel in their performance throughout adulthood and appear to e throughout adulthood and appear to be minimally affected by the aging prbe minimally affected by the aging processocess