Adaptations to Exercise TrainingAdaptations to Exercise Training

IntroductionIntroduction

Exercise training can be defined as Exercise training can be defined as participation in chronic, organized physical participation in chronic, organized physical activity, with the goal of improving athletic activity, with the goal of improving athletic performance or specific health and fitness performance or specific health and fitness parametersparameters

Principles of Exercise adaptationPrinciples of Exercise adaptationSpecificity of TrainingSpecificity of Training– A specific exercise elicits a specific training A specific exercise elicits a specific training

responseresponse

Overload PrincipleOverload Principle– Improvement in performance capacity occur when Improvement in performance capacity occur when

regular physical activity is increased above the regular physical activity is increased above the level that the performer usually experienceslevel that the performer usually experiences

– Three factorsThree factorsFrequencyFrequencyIntensityIntensitydurationduration

The Principle of Individual DifferencesThe Principle of Individual Differences– No two individuals are the sameNo two individuals are the same– Unique motor performance profile, and training Unique motor performance profile, and training

strategies may need to be customized to match the strategies may need to be customized to match the individual’s rate of improvementindividual’s rate of improvement

Types of Anaerobic Exercise TrainingTypes of Anaerobic Exercise TrainingIncreases in muscular strength generally Increases in muscular strength generally require exercise intensities of least 30% of require exercise intensities of least 30% of maximal voluntary contractile strength (MVC)maximal voluntary contractile strength (MVC)

Isometric ExerciseIsometric Exercise– No change in joint positionNo change in joint position– Desirable in some rehab. situationDesirable in some rehab. situation– Little or no equipmentLittle or no equipment– Can be done almost anywhereCan be done almost anywhere– Better to perform at various joint anglesBetter to perform at various joint angles

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Dynamic Resistance ExerciseDynamic Resistance Exercise– Changes in muscle length and joint anglesChanges in muscle length and joint angles– Concentric muscle contractions can offer very Concentric muscle contractions can offer very

forces and thus an appropriate overload stimulusforces and thus an appropriate overload stimulus– Eccentric muscle produce more muscular force Eccentric muscle produce more muscular force

than that obtained during an isometric muscle than that obtained during an isometric muscle contractioncontraction

– Eccentric or lengthening muscle contractions is Eccentric or lengthening muscle contractions is both highly fatiguing and highly susceptible to both highly fatiguing and highly susceptible to muscle sorenessmuscle soreness

Assessing Success of Anaerobic Assessing Success of Anaerobic Exercise TrainingExercise Training

Dynamic muscle strength can be estimated Dynamic muscle strength can be estimated using the 1 RM (repetition maximum)using the 1 RM (repetition maximum)

Anaerobic power maximum amount of force Anaerobic power maximum amount of force that can be generated over a period of timethat can be generated over a period of time– Margaria power test or Wingate cycling terstMargaria power test or Wingate cycling terst

Exercise TestsExercise Tests

Aerobic Exercise TrainingAerobic Exercise Training– Low intensity or relatively low force levelsLow intensity or relatively low force levels– Continuous trainingContinuous training

One type of aerobic exercise trainingOne type of aerobic exercise training– Exercise at a low intensity for a duration sufficient for Exercise at a low intensity for a duration sufficient for

creating an aerobic overloadcreating an aerobic overload

– Workload may be estimated as a percentage of maximum heart Workload may be estimated as a percentage of maximum heart rate or a percentage of VOrate or a percentage of VO2max2max

– Aerobic exercise should be performed at an intensity of about Aerobic exercise should be performed at an intensity of about 60 to 80% of maximal heart rate60 to 80% of maximal heart rate

Rating of Perceived ExertionRating of Perceived Exertion– Borg (1970s) discovered that our sense of effort Borg (1970s) discovered that our sense of effort

bears a close relationship to actual workloadbears a close relationship to actual workload– Borg’s scale correlates well with heart rate and Borg’s scale correlates well with heart rate and

VOVO22 maxmax

Rating of Perceived ExertionRating of Perceived Exertion

Interval TrainingInterval Training– Alternating higher-intensity Alternating higher-intensity

exercise bouts with rest exercise bouts with rest periods, overload stimuli periods, overload stimuli can be applied that stress can be applied that stress the intermediate energy the intermediate energy systems and long-term systems and long-term aerobic systemsaerobic systems

– Major advantage is that Major advantage is that more total work can be more total work can be done by dividing it into done by dividing it into several bouts than by several bouts than by performing it continuouslyperforming it continuously

Other Types of Exercise TrainingOther Types of Exercise Training

Fartlek training Fartlek training – Designed by Swedish exerciseDesigned by Swedish exercise– A type of alternating fast-slow trainingA type of alternating fast-slow training

Hollow sprintsHollow sprints– Alternate periods of sprint, jogging, and walkingAlternate periods of sprint, jogging, and walking

Long-Term Adaptations to Anaerobic Long-Term Adaptations to Anaerobic Exercise TrainingExercise Training

Muscle StrengthMuscle Strength– Muscle strength to Muscle strength to

increase with long-term increase with long-term resistance exercise resistance exercise trainingtraining

– Initial strength increase Initial strength increase can be dramaticcan be dramatic

– Most of gain occurs Most of gain occurs during the first month, during the first month, subsequent gains much subsequent gains much more slow,more slow,

– Strength decrease as Strength decrease as detraining persistsdetraining persists

– Major part of initial gain Major part of initial gain in strength originates in in strength originates in the nervous systemthe nervous system

– Learn how to activate Learn how to activate more motor units in the more motor units in the muscles responsible for muscles responsible for action or how to activate action or how to activate them more efficientlythem more efficiently

– Nervous system learns Nervous system learns task in a more task in a more coordinated fashioncoordinated fashion

Training the BrainTraining the Brain– Thinking about performing a maximal voluntary Thinking about performing a maximal voluntary

muscle contraction on a regular basis can improve muscle contraction on a regular basis can improve muscular strengthmuscular strength

Muscle Fiber AdaptationsMuscle Fiber Adaptations

Slow twitch muscle fibers Slow twitch muscle fibers are recruited or brought are recruited or brought into action first, with the into action first, with the fast twitch muscle fibers fast twitch muscle fibers recruited as the force recruited as the force increasesincreases

Fast-twitch fibers to Fast-twitch fibers to hypertrophy even more hypertrophy even more than slow-twitch fibersthan slow-twitch fibers

Long-Term Adaptations to Aerobic Long-Term Adaptations to Aerobic Exercise TrainingExercise Training

An expect of VOAn expect of VO2max2max to increase as the aerobic to increase as the aerobic

training program progresstraining program progress

Increase the efficiently of the oxygen Increase the efficiently of the oxygen utilization systemutilization system

Respiratory AdaptationsRespiratory Adaptations– Lung become more capable at extracting from the Lung become more capable at extracting from the

inhaled air and exchanging it for COinhaled air and exchanging it for CO22

Oxygen-Carrying AdaptationsOxygen-Carrying Adaptations– Increase myoglobin in muscle with endurance Increase myoglobin in muscle with endurance

exercise, facilitating the delivery of Oexercise, facilitating the delivery of O22 to to mitochondriamitochondria

Blood-Delivery AdaptationsBlood-Delivery Adaptations– Endurance training increases the size of the heartEndurance training increases the size of the heart– Total blood volume increases helps OTotal blood volume increases helps O22 delivery delivery

and regulation of body temperatureand regulation of body temperature– An increase in the number of RBC helps to An increase in the number of RBC helps to

provide more oxygen-carrying hemoglobinprovide more oxygen-carrying hemoglobin– Stroke volume increases with training Stroke volume increases with training

Energy Production AdaptationsEnergy Production Adaptations– More mitochondria in the trained individualsMore mitochondria in the trained individuals– Enzymes for aerobic metabolism increase in Enzymes for aerobic metabolism increase in

concentration and efficiencyconcentration and efficiency– Muscle learns to contain more glycogen Muscle learns to contain more glycogen – Beta-oxidation increases to better use fat stores for Beta-oxidation increases to better use fat stores for

energyenergy

Other Aerobic AdaptationsOther Aerobic Adaptations– Increase in the proportion of slow-fibersIncrease in the proportion of slow-fibers– Increase fatigability of most muscle fibersIncrease fatigability of most muscle fibers– Better handle the heat producedBetter handle the heat produced

Summary of Anaerobic and Aerobic Summary of Anaerobic and Aerobic Training AdaptationsTraining Adaptations

The The specificityspecificity and and overloadoverload principles are key principles are key to understanding and predicting adaptations to understanding and predicting adaptations that occurs with trainingthat occurs with training

Floor-and-ceiling effect of hemoglobinFloor-and-ceiling effect of hemoglobin

Antagonism between Anaerobic and Aerobic Antagonism between Anaerobic and Aerobic TrainingTraining– Training aerobically may hinder anaerobic Training aerobically may hinder anaerobic

performance and vice versaperformance and vice versaStrength training decrease muscle myoglobin contentStrength training decrease muscle myoglobin content

Resistance exercise training increase the proportion of Resistance exercise training increase the proportion of fast-twitch muscle fibersfast-twitch muscle fibers

DetrainingDetrainingOnce training stops, the positive effects of Once training stops, the positive effects of resistance exercise or endurance training wear resistance exercise or endurance training wear off at about the same rate that training off at about the same rate that training occurredoccurred

The Space EnvironmentThe Space Environment

30 days of space flight, 30 days of space flight, – muscle may atropy as much as 20%, muscle may atropy as much as 20%, – muscle strength decrease by about 20%muscle strength decrease by about 20%– Bone mass decrease about 1 to 2 % per monthBone mass decrease about 1 to 2 % per month– Problems in balance and postural controlProblems in balance and postural control

VOVO2max2max can decrease by as much as 25% after can decrease by as much as 25% after

20 day of bed rest20 day of bed rest

Percent change in Percent change in gastrocnemius and gastrocnemius and soleus muscle volume soleus muscle volume from preflight to from preflight to postflight recovery days postflight recovery days 4 (R+4) and 19 (R+19). 4 (R+4) and 19 (R+19). *P < 0.05 vs. preflight. *P < 0.05 vs. preflight. †P < 0.05 vs. †P < 0.05 vs. gastrocnemius. gastrocnemius.

Scott Trappe et al., 2009

OvertrainingOvertraining

Overtraining is a physical, behavioral, and Overtraining is a physical, behavioral, and emotional condition that occurs when the emotional condition that occurs when the volume and intensity of an individual's volume and intensity of an individual's exercise exceeds their recovery capacity. exercise exceeds their recovery capacity. They cease making progress, and can even They cease making progress, and can even begin to lose strength and fitness. begin to lose strength and fitness. Overtraining is a common problem in weight Overtraining is a common problem in weight training, but it can also be experienced by training, but it can also be experienced by runners and other athletes.runners and other athletes.

OvertrainingOvertraining

General adaptation syndromeGeneral adaptation syndrome– Hans Selye (1950s), stressed and allowed to Hans Selye (1950s), stressed and allowed to

recover, rats grew stronger, if repeatedly stressed recover, rats grew stronger, if repeatedly stressed without sufficient time for recovery, rats grew without sufficient time for recovery, rats grew weakerweaker

Cure for overtrainingCure for overtraining– Reduce the intensity, duration, frequency of Reduce the intensity, duration, frequency of

exerciseexercise– Training levels should be increased slowly and Training levels should be increased slowly and

regular rest periodregular rest period– Maintain adequate diet and plenty of sleepMaintain adequate diet and plenty of sleep

TaperingTaperingRefers to the practice of reducing exercise in the days Refers to the practice of reducing exercise in the days just before an important competition.just before an important competition.

Tapering is customary in many endurance sports, Tapering is customary in many endurance sports, such as the marathon, athletics and swimming. such as the marathon, athletics and swimming.

For many athletes, a significant period of tapering is For many athletes, a significant period of tapering is essential for optimal performance. The tapering essential for optimal performance. The tapering period frequently lasts as much as a week or moreperiod frequently lasts as much as a week or more

TaperingTapering

Swimmers decrease their training for 15 days Swimmers decrease their training for 15 days resulted in a 25% increase in muscular power resulted in a 25% increase in muscular power and 4% performance improvementand 4% performance improvement

Reducing training volume several weeks Reducing training volume several weeks before big meet to enhance performancebefore big meet to enhance performance

Tapering may be one way of compensating for Tapering may be one way of compensating for overtraining during part of the training period overtraining during part of the training period

DiscussionDiscussion

What biochemical changes may occur each What biochemical changes may occur each bout during interval training (glucose, lactate bout during interval training (glucose, lactate etc.) and why. etc.) and why.

Can you using the University’s campus, Can you using the University’s campus, (gymnasiums, stadiums, buildings etc.) to plan (gymnasiums, stadiums, buildings etc.) to plan a Fartlek training (drawing a running course) a Fartlek training (drawing a running course) for distance runner.for distance runner.

How do you do to detect subjective and How do you do to detect subjective and objective overtraining to athletes.objective overtraining to athletes.