Mod 1: Intro to Exercise Physiology and Bioenergetics

Question 1

What is bioenergetics?
The study of _______ _____ via __________ ________ in __________ ____________

Answer 1

The study of energy transfer via chemical reactions in living tissues

Question 2

what does the first law of thermodynamics state?

Answer 2

” Energy cannot be created nor destroyed…only transferred from one form to another”.

delta E= usale E(free E) + Non usable E (heat)

Question 3

list 4 factors that affect enzyme activity

Answer 3

1. substrate and product concentrations
2. Modulator(eg, ADP)
3. temp
4. pH

Question 4

what is the relationship between the amount of substrates and enzyme activity?

Answer 4

as the amount of substrate increases, the ROR increases until all enzymes are saturated. To increase the ROR further, get more enzymes through exercise adaptations(training)

Question 5

What is the effect of modulators on the ROR

Answer 5

affect ROR at given substrate concentration.
-can speed or slow ROR (stimulators speed up(cap opens when stimulator is present ex. ADP), inhibitors slow down because cap doesnt open)

Question 6

What is the effect of temp on enzyme activity?

-what temp do they work best at?
-do they denature faster at hotter or colder temps?

Answer 6

-work best at 38 degrees
-denature faster at hotter temps(more steep)

Question 7

What is the effect of pH on enzyme activity?

-what pH do they work best at?

-give lactic acid example, how do athletes counter acidic blood when exercising?

Answer 7

-work best at 7.0 pH (normal body pH=7.1)

-when exercising, lactic acid accumulates, pH goes from 7–> 6.5 (acidic)

-athletes counter this by taking Tums (sodium bicarbonate) prior to exercise to make muscle pH basic (increase) so when they start exercising and pH decreases it reaches around 7 so their enzymes can work optimally. can cause GI distress

-ergogenic: intended to improve physical performance, stamina, recovery

Question 8

Catabolism vs. Anabolism

Answer 8

Catabolism: breakdown of molecules
Anabolism: synthesis of molecules

Question 9

what are the 3 types of ATPase enzyme and their purpose?

(DEMAND)

Answer 9

1. Ca 2+ ATPase: release energy for Ca to be released from sarcoplasmic reticulum
2. Myosin ATPase: allows crossbridge muscle contraction cycling
3. Na/K ATPase: nerve impulses

Question 10

what are the 3 SUPPLY

(muddy concept) supply vs demand

Answer 10

1. phosphagen breakdown
2. non-oxidative glycolysis
3. oxidative metabolism

Question 11

give 3 characteristics of Type 1 (slow twitch) fibres

Answer 11

1. can maintain exercise for prolonged periods
2. require oxygen for ATP production
3. recruited for low-intensity aerobic exercise and daily activities

Question 12

give 3 characteristics of Type 2(fast twitch) fibres

(chart comparing 1 and 2 in mods last slide)

Answer 12

1. fatigue quickly
2. produce more force
3. produce ATP anaerobically

(IIA vs IIX)

Question 13

What does the stimulator and inhibitor bind to?

(Substrate or enzyme?)

Answer 13

ENZYME

Question 14

Exercise is the demand that results in buildup of ADP through breakdown of atp by ATPases .

What is the supply to meet the energy demand?

Answer 14

-3 ways to produce ATP: phosphagen breakdown, nonoxidative glycolysis(both anaerobic), in cytoplasm of mitos, oxidative metabolism( aerobic, relies on oxygen to produce ATP IN mitos)

Question 15

What are some oxidative metabolism substrates?

Answer 15

fats(stored in adipose tissue (triglycerides),
free fatty acids to transport in bloodstream to get to muscle, triglycerides)
and carbs

Question 16

Once glucose is in skm can it go back out in to the bloodstream? Why?

Answer 16

NO
- trapped in cell by adding phosphate group to it by enzyme Hexokinase in muscle and phosphofruktokinase in liver
-when glucose enters muscle its stored as glycogen to broken down anaerobically(glycolysis) or aerobically