Kin 381 - Adaptation

homeostasis

- the tendency for the human body to keep all systems at a default level

heterostasis

- idea that different parts of the body can be maintained deliberately out of sync with each other
- body desires to "normalize as quick as possible"

regular exercise

- body learns to maintain the normal function values longer in balance and restore function more quickly

adaptation

- the body learns to cope with the repeated demands through functional and morphological adaptations

aerobic training adaptations

- increased:
> cardiac output
> blood volume
> hematocrit
> heart volume
> blood flow to lungs
> size/number of mitochondria
> mitochondrial enzyme activity
> capillarization
> fat oxidation enzyme activity
> blood supply to heart
> stroke volume
> left ventricle volume
> ventricular wall thickness
- Decreased:
> peripheral resistance

resistance training adaptations

- increased
> muscle strength
> muscle power
> balance and coordination
> BMR
> lean tissue mass
> muscle endurance
> motor performance
> insulin sensitivity
- Decreased:
> % body fat
> low back pain
> sarcopenia and osteoporosis
> insulin concentration/response to glucose challenge

- increase of individual cross-section of a muscle fibre
- dependent on resistance to muscle contraction and total number of concentrations

myofibril hypertrophy

- contractile hypertrophy

sarcoplasmic hypertrophy

- non-contractile hypertrophy
- increase interfibrillar fluid, ATP, glycogen, phosphocreatine, mitochondria

fast glycolytic

- increase with training
- high contraction rates
- large force

fast oxidative-glycolytic

- increase with training
- high oxidative and glycolytic enzymes
- increased potential for powerful muscle contraction

60

Myosin makes up ____% of the total protein content of a muscle fibre with actin and tropomyosin making the next largest contributions therefore - increased myofibrillar protein

fibre type %

- aerobic exercise causes increase in more type 1 fibre (oxidative)
- same is true for any other type of activity including resistance training

true

True or False: fibre type is genetically determined

aerobic training (enzymes)

- increases activity of oxidative enzymes (citrate synthase, Krebs cycle, presence of mitochondria)
- reduction in activity of anaerobic enzymes
- increased blood volume
- increased mitochondrial and capillary density

neural adaptation

- level of the CNS and spinal level
- increase strength without increase cross-sectional area
- increased neural drive of agonist activation
- increased motor unit firing, increased motor cortex signal
- decreased antagonist activation

connective tissue adaptations

- most animal studies indicate that endurance and resistance training can increase max strength of tendons and ligaments

bone adaptations

- PA (stress/strain) causes an increase in BMD
- weight bearing / tendon stress through resistance training are indicated
- site specific

wolff's law

- the densities, and to a lesser extent, the sizes and shapes of bones are determined by the magnitude and direction of the acting forces applied to bone

first 2-6 weeks (resistance training)

- rapid increase in strength due to neural adaptations
- no difference in rate of progressions between males and females
- some cellular / mechanistic adaptations
- hypertrophy may occur faster than previously thought

10+ weeks (resistance training)

- continued strength gains mostly due to cellular adaptations
- greater hypertrophy in males due to presence of androgenic anabolic hormones (testosterone)