ES - Knowledge of Anatomical, Physiological, and Biomechanical differences of athletes

Question 1

Sex Differences - Body Size and Composition
Stature
BF, Muscle, BMD
Anthropometric measurements

Answer 1

Adult men have greater over stature than adult women.
On average, adult women tend to have more body fat, less muscle, lower bone mineral density, and tend to be a lighter weight than men.
Although some women have lower BF% than men, extremely low BF% in women may be associated w/ adverse health consequences.
Anthropometric measurements: men tend to have broader shoulders relative to hips to support more muscle tissue and provide a mechanical advantage for muscles acting at the shoulder.
Women have broader hips relative to their waist and shoulders.

Question 2

Sex Differences - Absolute strength

Answer 2

women generally have ~2/3 strength of men. The absolute lower body strength of women is generally closer to male values as compared to the absolute values for upper body strength.
Women are generally weaker than men b/c of their lower quantity of muscle.

Question 3

B/c the average man and woman differ considerably in body size, it’s useful to compare sex differences in strength relative to… (3)

Answer 3

body weight
fat-free mass
muscle cross-sectional area

Question 4

Relative to body weight, lower body strength of women is…

If comparisons are made relative to….

Answer 4

Relative to body weight, lower body strength of women is similar to men, while upper body strength of women is still somewhat less.
If comparisons are made relative to fat-free mass, differences in strength between men and women tend to disappear.

Question 5

Eccentric v Concentric Strength in men v women

Answer 5

data suggests eccentric strength msg be more similar between men and women than concentric strength when compared relative to fat-free mass.

Question 6

Strength differences relative to muscle cross-sectional area for men v women

Answer 6

when strength is expressed relative two muscle cross-sectional area, no significant difference exists between sexes, which indicates that muscle quality (peak force per cross-sectional area) is not sex specific.

Question 7

Sex differences and muscle fibers

Answer 7

Even though muscle fibers in men and women are also similar in fiber type distribution sand histochemical characteristics, men tend to have a larger muscle fiber cross-sectional area.

Question 8

Sex difference and power output

Answer 8

similar to muscle strength.
Women’s power output relative to total body weight was ~63% of men’s during snatch and clean pulling movements.
Vertical and standing broad jumps are lower than men (smaller gap when compared relative to fat-free mass).
Sex related differences in rate of force development and the recruitment strategy of muscle activation partly explain these findings.

Question 9

Basic differences in physiological adaptations that occur between prepubescents as compared to adults

Answer 9

a

Question 10

How does bone mineral density change w/ age?

Answer 10

BMD decreases and bone porosity (full of tiny holes) increases, causing bones to become fragile over time.
Osteopenia: BMD of -1 to -2.5 standard deviation of young adult mean/
Osteoporosis: BMD of

Question 11

Osteopenia and Osteoporosis

Answer 11

Osteopenia: BMD of -1 to -2.5 standard deviation of young adult mean/
Osteoporosis: BMD of

Question 12

How does force production change w/ age?

Answer 12

Reductions in the size and number and the gradual denervation of muscle fibers lead to a decrease in power generation and force production.
Decrease in force production affects ability for older adults to perform activities like climbing stairs and walking.
Power decreases at a faster rate than muscle strength w/ aging.
Decrease in muscle cross-sectional area, decreased muscle density, reductions in tendon compliance, and increased intramuscular fat after age 30.

Question 13

How does aerobic endurance change w/ age?

Answer 13

Maximal aerobic power decreases w/ age b/c of reduced muscle mass and strength, and increased fat mass in both trained and untrained.

Question 14

Aerobic power in men v women

Answer 14

On average, when men and women are matched by age, aerobic power values of women range from 73%-85% of the values of men. These differences may be caused by physiological differences such as: women’s higher BF% and lower blood hemoglobin and men’s larger heart size and blood volume.

Question 15

Initial adaptations that account for strength gains as a result of resistance training?
What adaptations occur later?

Answer 15

Table 5.2

Question 16

Unchanged or decreased adaptations to resistance training

Answer 16

Decreased:
Capillary density (no change possible)
Mitochondrial Density
BF%

No change:
Myofibrillar Density
Lactate dehydrogenase
Aerobic power (may increase slightly)

Question 17

What adaptations of resistance training occur later?

Answer 17

As an individual continues resistance training, the CNS may adapt by allowing the recruitment of more motor units in a nonconsecutive order; i.e. by recruiting larger motor units first to promote greater production of power or speed in a movement.
Level of tissue activation also results from chronic resistance training for hypertrophy. As muscle size increases it doesn’t require as much neural activation to lift a given load. Suggesting the importance of progressive overloading.

Question 18

Physiological adaptations of aerobic exercise - (Performance)
Muscle strength
Muscle endurance
Aerobic power
Max rate of force production
Vert Jump
Anaerobic power
Sprint speed

Answer 18

MS - no change
ME - increases for low power output
AP - increases
Max ROFP - no change or decreases
VJ - ability unchanged
AP - no change
SS - no change

Question 19

Physiological adaptations of aerobic exercise - (Muscle Fibers)
Fiber size
Capillary density
Mitochondrial density
Myofibrillar packing density and volume
Cytoplasmic density
Myosin heavy chain protein

Answer 19

FS - no change or increase slightly
CD - increases
MD - increases
Myofib. PD and V - no change to either
Cyto Den. - no change
MHCP - no change or decreases in amount

Question 20

Physiological adaptations of aerobic exercise - (Enzyme activity)
Creatine phosphokinase
Myokinase
Phosphofructokinase
Lactate dehydrogenase
Sodium-potassium ATPase

Answer 20

Cr PhoKi. - increases
Myokinase - increases
PFK - variable
LDH - variable
NaK ATPase - may slightly increase

Question 21

Physiological adaptations of aerobic exercise - (Metabolic energy stores)
Stored ATP
Stored Creatine phosphate
Stored glycogen
Stored triglycerides

Answer 21

ATP - increases
CP - increases
Glycogen - increases
Triglycerides - increase

Question 22

Physiological adaptations of aerobic exercise - (Connective Tissue)
Ligament strength
Tendon strength
Collagen content
Bone density

Answer 22

Ligament strength - increases
Tendon strength - increases
Collagen content - variable
Bone density - no change or increases

Question 23

Physiological adaptations of aerobic exercise - (Body comp.)
%BF
Fat-free mass

Answer 23

%BF - decreases

FFM - increases

Question 24

Performance improvements following anaerobic exercise - (Muscular strength)

Answer 24

During periods of 4 weeks to 2 years, mean strength can increase approx. 
40% in untrained
20% in moderately trained
16% in trained
10% in advanced
2% in elite

Positive shift in muscle fiber types for higher-order MU’s. Type Iix transitions to II and reflects greater fatigue resistance at similar absolute force outputs.

Question 25

Performance improvements following anaerobic exercise - (Power)

Answer 25

Optimal load for maximizing peak power in jump squat is 0% 1RM (body weight).
Optimal load for maximizing peak power output in trained power athletes w/ higher loads is 30%-60% squat 1RM.
Peak power in squat is maximizing at 56% 1RM and 80% for power clean.
Upper body, peak power output is can be maximized during “ballistic bench press throw” using loads corresponding to 46%-62% 1RM of bench press.

Question 26

Performance improvements following anaerobic exercise - (Local Muscular Endurance)

Answer 26

Enhanced muscle endurance and subsequent muscular adaptations consistent w/ improved oxidative and buffering capacity.
Fiber type transitions from Type Iix to Type IIb, as well as increases in mitochondrial and capillary numbers, buffering capacity, resistance to fatigue, and metabolic enzyme activity.

Question 27

Performance improvements following anaerobic exercise - (Body Composition)

Answer 27

Resistance training can increase free-fat mass and reduce body fat.
Increases lean tissue mass, daily metabolic rate, and energy expenditure during exercise are also outcomes.

Question 28

Performance improvements following anaerobic exercise - (Flexibility)

Answer 28

Anaerobic training has positive impacts on flexibility.
A combo of resistance training and stretching seems to be the most effective method to improve flexibility w/ increasing muscle mass.

Question 29

Performance improvements following anaerobic exercise - (Aerobic Capacity)

Answer 29

In untrained people, heavy resistance training can increase VO2max from 5% to 8%.
In trained people, resistance training does not significantly increase aerobic capacity.

Question 30

Performance improvements following anaerobic exercise - (Motor Performance)

Answer 30

increases seen in running economy, vertical jump, sprint speed, tennis serve velocity, swinging and throwing velocity, and kicking performance.

Question 31

Improvements following aerobic exercise - (Respiratory System)

Answer 31

decreased submaximal respiration rate

Question 32

Improvements following aerobic exercise - (Cardiovascular System)

Answer 32

Decrease HR for fixed submax. workloads associated w/ increased stroke volume and cardiac output.
Increase blood volume to support increase stroke volume and cardiac output.

Question 33

Improvements following aerobic exercise - (Musculoskeletal System)

Answer 33

Increased arterial-venous O2 differences associated w/ increased capillarization in muscle, increased oxidative enzyme concentrations, and increased mitochondrial size and density.

Question 34

Improvements following aerobic exercise - (Aerobic Power; max O2 uptake)

Answer 34

Increase maximal O2 uptake (VO2max).
Elite athletes may show minor changes in VO2max w/ training (5%-10%). Untrained can see as much as 20%.
A high VO2max combined w/ increased lactate threshold allows enhanced performance for running sports as well as sports requiring intermittent sprinting (soccer, basketball, etc.).

Question 35

Improvements following aerobic exercise - (Lactate threshold)

Answer 35

Increased absolute lactate threshold, allowing the highly trained individual to work at both higher relative and absolute percentage. These increases result in: running at higher % of VO2max for a race (resulting in faster times), covering more distance during a game, enhanced recovery for second-half performance, and working at higher exercise intensities throughout an event.
Higher % of VO2max = better maintenance of power output.

Question 36

Improvements following aerobic exercise - (Effective utilization of substrate)

Answer 36

Greater use of fats as a substrate for exercise w/ a relative sparing of carbs. By sparing carbs, the endurance athlete can can maintain higher-intensity exercise for longer periods of time.
Aerobic exercise may be improved through various carb loading manipulations to increase endogenous (internal) glycogen stores.

Question 37

Improvements following aerobic exercise - (Muscle fiber adaptations)

Answer 37

elite distance runners have higher proportion (percentage) of Type 1 fibers, and the available Type I fibers are functionally very efficient for aerobic metabolism (increased mitochondrial density and oxidative enzyme capacity and capillary net=work for oxygen delivery).
Long distance and intermittent aerobic training results in increased oxidative capacity of Type I fibers.
Muscle fibers can alter their myosin heavy chain and internal characteristics, leading to alterations in classification of fibers and the observation that Type Iix fibers are increased in endurance trained athletes.
These metabolic and fiber changes result in more efficient use of aerobic energy production.

Question 38

Improvements following aerobic exercise - (Exercise efficiency)

Answer 38

Mostly a function of technique and biomechanics.
An athlete w/ more efficient exercise (i.e. requiring less energy to maintain the same power output) will sustain same power output for longer duration, even if two athletes have the same VO2max and lactate threshold.