Lecture 3

Question 1

Where does immediate energy come from?

Answer 1

The ATP-PC System

Question 2

How much energy is stored in our muscles?

Answer 2

ATP=5 mmol/kg

PCr=15mmol/kg

Question 3

What is the purpose of creatine?

Answer 3

to improve muscle performance, promote strength, recovery and performance

Question 4

What is the creatine loading protocol?

Answer 4

-0.3g/kg/day of creatine for at least 3 days then 3-5g/day to maintain elevated stores

Question 5

Theoretical basis for creatine?

Answer 5

• creatine phosphate stores limit ATP production and performance during maximal exercise conducted over short periods of time
• so supplementation will increase cellular CP level and increase the duration of high intensity performance

Question 6

Where does short term energy come from?

Answer 6

The Lactic acid system

Question 7

Where does the ATP from the Lactic Acid system come from?

Answer 7

• ADP comes from glucose and stored glycogen
• system is used with the ATP-PC system is depleted or if oxygen supply is inadequate (or oxygen demand exceeds oxygen utilization)

Question 8

Blood Lactate accumulation

Answer 8

when lactate removal is slower than lactate production does

Question 9

2 classifications of fatigue?

Answer 9

central and peripheral

Question 10

Central fatigue

Answer 10

not localized in a specific muscle and affects the entire body
-CNS, metabolic, and psychological factors

Question 11

Peripheral fatigue

Answer 11

• exhaustion: depletion of energy substrates (ATP, CP, glycogen)
• accumulation: of metabolic by products (H+ from lactic acid)

Question 12

Bicarbonate Loading

Answer 12

loading with sodium bicarb has been proposed to push back the lactate threshold
and bicarb can push accumulating lactic acid from muscle into extracellular spaces for disposal and limit fatigue

Question 13

Bicarb loading protocol

Answer 13

-household sodium bicarb mixed with water
acute method: 0.3g/kg of body weight 1 hr before competition
chronic method: 0.5g/kg divided in 4 doses throughout the 5/6 days leading up to the event

Question 14

Side effects of bicarb loading

Answer 14

G.I distress (nausea, stomach pain, diarrhea, vomiting), can interact with other supplements and foods

Question 15

What system do you use if you need long term energy?

Answer 15

The Aerobic system

Question 16

Oxygen uptake

Answer 16

the use of oxygen by cells

Question 17

Steady state

Answer 17

the plateau of oxygen uptake around 3-4 minutes after oxygen uptake rises rapidly and then remains stable

Question 18

What does aerobic metabolism require?

Answer 18

carbs (glycogen and glucose)

fats (triglycerides and fatty acids)

Question 19

McArdle’s syndrome

Answer 19

Inborn error in muscle glycogen metabolism

• cannot synthesize phosphorylase
• so you can’t break down glycogen in the muscle
• muscle fibres are broken which leads to muscle pain, cramping, fatigue and tenderness

Question 20

Goal of carbohydrate loading

Answer 20

muscle glycogen super compensation

-larger glycogen stores help to ensure the body stays in steady state aerobic metabolism which increases endurance

Question 21

Carb loading approach

Answer 21

• taper training 6-7days prior to event

- gradually increase carb to 65-70% of total calories

Question 22

Benefits for carb loading

Answer 22

• will only benefit endurance athletes
• need to be exercising for 90mins or more
• can nearly double muscle glycogen concentrations=increased endurance

Question 23

Downside of carb loading

Answer 23

• for every g or glycogen store 4g are also stored
• muscle stiffness, heaviness and cramping
• risk for glycogen deposition in cardiac muscle

Question 24

When is protein used as fuel?

Answer 24

only if carb is not available

glucogenic AA are converted to glucose through gluconeogenesis and then glucose is used to generate carbs

Question 25

Oxygen deficit

Answer 25

• difference between total oxygen consumed during exercise and amount that would have been used at steady-rate of aerobic metabolism
• energy during this phase comes from ATP-PC and Lactic acid system

Question 26

EPOC

Answer 26

excess post-exercise oxygen consumption
the measurably increased oxygen uptake observed following vigorous PA
intended to replete the body’s oxygen deficit

Question 27

Recovery Eating

Answer 27

Glycogen repletion is up-regulated in the period right after intense exercise
eating immediately after exercise can help an athlete recover faster and come back to training sooner
goals: high glycemic index foods /beverages within 30 mins of exercise and additional high carb foods within the next 2 hours