Chapter 16 - Training for Sport

postive stress

training that causes improvements in exercise performance

how long do major training adaptations take?

6-10 weeks

what is positive stress dependent on?

volume and intensity of training

rate of adaptation is ______

genetically limited

balance of volume and intensity

• must include trest

• correct balance enhances performance

overtraining

• performance decrements

• chronic fatigue

• overuse injury, overtraining syndrome

progressive overload necessary

• progressively increases with stimulus as body adapts

• stimulation of continuous improvements

undertraining

• insufficient stimulus

• adaptations not fully realized

• optimal performance

overtraining

• loss of benefits

• no additional improvements

• performance decrements, injury

optimizing training: a model

• undertraining

• acute overload

• overreaching

• overtraining

under training

• off-season

• optimal time for break

acute overload

• average training load

• think of it as a workout every time you wou

overreaching

• decrement, then benefit

• ex: you lift and then your arms are sore the next day

• ex: ex resting and overtime perform more

overtraining

• maladaptations

• performance decreases

• overtraining syndrome, excessive training

overreaching definition

• systematic attempt to overstress body for a short period of training

• short performance decrement followed by improved performance and function

systemic attempt to over stress body for a short period of time (overreaching)

• allowed body to adapt to stronger stimulus

• not same as excessive training

• caution: easy to cross into overtraining

excessive training

• volume, intensity, or both to extreme

• possible decrease in strenght, sprint to performance

• training volume should be sport specific

• value of high-volume training is questionable

• intensity and volume are inversely related

• increase in intensity + increase in volume → negative effects

volume, intensity, or both to extreme

• for years, many athletes undetrained

• as intensity or volume increases, so did performance

• but more is better is not true after a point

• ex: swim training 3-4 hours a day no better than 1-1.5 hours a day

possible decrease in strength, sprint performance

• max out your training

• just because you can do more doesn’t mean you should do more

swim study (excessive training)

• single vs. multiple daily training sessions

• result: no evidence that more is better

  • similar heart rate and blood lactate improvements

  • no additional improvements from 2 times per day

value of high-volume training is questionable

• in some sports, half the volume may maintain benefit and decrease risk

• ex: low-intensity, high-volume approach is inappropriate for sprint-type performance

intensity and volume are inversely proportional

• if volume increases, intensity should decrease

• if intensity increase volume should decrease

• different emphasis leads to different fitness results

• applies to resistance, anaerobic, and aerobic training

  • applies to basically everything

periodization of training definition

schedule out training

periodization of training characteristics

• traditional periodization programd divide into cycles ranging from multipyear to microcycles (a few days)

• best for athletes who focus on one competition

• not optimal for team sports or for sports requring skill development

• includes general exercises and specific exercises to stimulate motor skills

block periodization

• gaining popularity

• allows focus on a few skills or attributes

• uses tree or four blocks that last 2-4 weeks

overtraining

• unexplained decrease in performance and function for weeks, months, or years

  • cannot be remedied by a short-term decrease in training, rest

  • may have psychological and physiological causes

  • can occur with all forms of training

• not all fatigue product of overtraining

overtraining system

• highly individualized, subjective

• necessary to rule out other causes

• possibly related to intensity of volume (training errors)

symptoms of overtraining syndrome

• decrease in strength, coordination, capacity

• fatigue

• change in appetite; weight loss

• sleep and mood disturbances

• lack of motivation, vigor, or concentration

• depression

psychological factors of overtraining syndrome

• emotional pressure of competition → stress

• parallel with clinical depression

physiological factors of overtraining syndrome

• autonomic,endocrine, and immue

• not a clear cause-and-effect relation but significant parallels

overtraining syndrome: sympathetic nervous system

• increased blood pressure

• loss of appetite

• weight loss

• sleep and emotional disturbances

• increased basal metabolic rate

overtraining syndrome: parasympathetic nervous system

• early fatigue

• decreased resting heart rate

• decreased resting blood pressure

• rapid heart rate recovery

• more common with endurance athletes

overtraining syndrome: endocrine responses

• resting thyroxine and testosterone decrease

• resting cortisol increase

• testosterone-to-cortisol ratio

• Volume-related overtraining apparently more likely to affect hormones

• increased blood urea concentration

• resting catecholamines increas

outside factors of endocrine system with overtraining syndrome

• overreaching may produce same trends

• time between last training bout and resting blood sample is critical

• blood markers are helpful but not definitive diagnostic tools

overtraining syndrome: neural and endocrine factors

• overtraining stressors may act primarily through hypothalamic signals

• hormonal axes are involved

overtraining stressors may act primarily through hypothalamic signals

• can lead to sympathetic neural activation

• can ldea to pituitary endocrine cascade

hormonal axes are involved

• sympathetic-adrenal medullary (SAM) axis - epinephrine and norepinephrine

• hypothalamic-pituitary-adrenocorticcal (HPA) axis - cortisol

overtraining syndrome: immune responses

• circulating cytokines

• inflammation → increase in cytokines via monocytes

• may act on brain and body functions, contribute to overtraining symptoms

• compromised immune function is a factor in onset of overtraining syndrome

• overtraining suppresses immune function

circulating cytokines

• “low-level” sick

• mediate inflammatory response to infection, injury

• increase in response to muscle, bone, and joint trauma

• increase in physical stress + decrease in rest → systemic inflammation

overtraining suppresses immune function

• mores susceptible to getting sick

• abnormally decreases lymphocytes and antibodies

• increase in inciddenc of illness after exhaustive exercise

• exercise during illness → immune complications

How to predict overtraining syndrome?

• causes unknown, diagnostics difficult

• threshold different for each athlete - individual

• intuition (unreliable) used by most coaches and trainers

• no preliminary warning symptoms

• biological markers: limitedd effectiveness

no preliminary warning symptoms

• no noticeable change in mood, performance, or behavior

• coaches do not realize until it is too late

• recovery takes days, weeks, or months of rest

treatment of overtraining syndrome

• reduced intensity

• rest (weeks, months)

• councseling to deal with stress (therapy)

prevention of overtraining syndrome

• periodization training

• adequate caloric intake (especially carbohydrates)

Execise addiction

• maladaptive because can threaten overall health, increase injury, ruin professional and personal relations

• distinguished by continuing to exercise despite injury, inconvenience, disruption, and lack of time

peak performance

• tapering involves reducing training volume or intensity

• results in increased muscular strength

• does not result in deconditioning

• leads to improved performance

tapering involves reducing training volume or intensity

• not stopping, just slowing down

• before major compeittion (recovery, healing)

• 4-28 days (or longer)

• most appropriate for infequent competition

results in increased muscular strength

• possibly associated with contractile mechanisms

• muscles repaired, glycogen reserves replenished (remake everything)

does not result in deconditioning

• reduce intensity

• considerable training to reach VO2max

• possible to reduce training volume by 41-61% and maintain VO2 max

leads to improved performance

• 3% improved race time

• 25% improved arm strength, power

• effects unknown for team sports, marathons

detraining

• loss of training-induced adaptations

• brief period = tapering

• longer period = detraining

• immobilization

• training cessation

• Loss mitigated by low-level exercise

• muscle endurance decreases quickly

• oxidative enzyme activity decreases by 40-60%

• muscle glycogen stores decrease by 40%

• significant acid-base imbalance

• weekly exercise test during detraining

• significant cardiorespiratory losses

loss of training-induced adaptations

• partial or complete

• due to training reduction or cessation

• musch mores substantial change than tapering

bried period =

tapering

longer period =

detraining

immobilization

• immediate loss of muscle mass, strength, power

• injury

training cessation

• variation in rate of strength and power loss

• “I don’t feel like working out anymore”

causes of detraining

• atrophy (immobilization)

• reduced ability to recruit muscle fibers

• altered rates of protein sythesis versus degradation

loss mitigated by low-level exercise

• any training is better than none

• lessen the amount of injury

muscle endurance decreases quickly

• change seen after 2 weeks of inactivity

• not clear whether results from muscle changes or cadiovascular changes

with detraining, oxidative enzyme activity decrease by

40-60%

with detraining, muscle glycogen stores decrease by

40%

weekly exercise test during detraining:

• blood lactate accumulation increases

• bicarbonate decreases

• pH decreases

training

only moderate increase in speed and agility

speed and agility with detraining

• only moderate decrease in speed and agility

• form, skill, flexibiilty are lost

• sprint performance still suffers

bed rest studies with detraining

• significant increase in submaximal heart reate

• 25% decrease in submaximal stroke volume (due to decrease in plasma volume)

• 25% decrease in maximal cardiace output

• 27% decrease in VO2 max

in trained athletes, VO2max lost is ____ with detraining, and regained more ______

faster, slowly

how much activity is needed to prevent losses in physical conditioning?

• losses occur when frequency and duration decrease by 2/3 of regular training load

____ if VO2 max training is sufficient to maintain maximal aerobic capacity

70%

losses occur when frequency and duration decrease by ____ of regular training load

2/3

detrainig in space

• microgravity exposure = detraining

• muscle mass and strength decrease

• stroke volume increases

• total blood volume decreases

• VO2 max decreases immediatly postflight

• with bed rest, VO2 max decreases

microgravity exposure = detraining

• normal gravity challenges heart and muscles

• detraining may be beneficial in space

muscle mass and strength decreases

• particularly postural muscles

• type I, II fiber cross-sectional area decreases

• without muscle stress, bone loss is about 4%

stroke volume increase with detraining in space

• less hydrostatic pressure, no blood pooling in lower extremities

• more venous return

total blood volume decreases with detraining in space

• plasma volume decreases due to decrease in fluid intake, increase capillary filtration

• red blood cell mass decreases

• in space → beneficial adaptation

• on earth → orthostatic hypotension

VO2 max decreases immediately post flight with detraining in space

• due to decrease in plasma volume and leg strength

• preflight, in-flight VO2 max data unknown

with bed rest, VO2 max decreases with detraining in space

• decrease in total blood volume

• decrease plasm volume and maximal stroke volume

what helps preserve astronauts’ long-term health?

in-flight exercise