AS Exercise Physiology - Diet and Nutrition

Question 1

Define glycogen loading and which performers would typically use this

Answer 1

Dietary manipulation - increase muscle glycogen stores above normal - increases performance duration and intensity

Used by endurance athletes

Question 2

Describe the process of glycogen loading

carb-cycling

Answer 2

• 6 days before competition - diet high in protein and exercise intensity is higher for 3 days - fully depletes glycogen stores
• Followed by 3 days of high carbs and lighter training
• Theory is that depleting always stores to be increased by up to 2 times the original amount

Question 3

Positive and negative effects of glycogen loading

Answer 3

Positive:
- Increased glycogen storage
- Increased muscle glycogen 
- Delays fatigue
- Increased endurance capacity
Negative:
- Water retention - causes bloating
- Heavy legs
- Weight increase
- Irritability during depletion phase
- Lack of energy during depletion phase

Question 4

Positive and negative effects of creatine monohydrate

Answer 4

Positive:
- Aims to provide ATP
- Replenishes PC stores
- Allows ATP-PC to last longer
- Increases muscle mass
Negative:
- Possible side effects: muscle cramps, diarrhoea, water retention, bloating, vomiting
- Hinders aerobic performance 
- Mixed evidence

Question 5

Positive and negative effects of sodium bicarbonate

Answer 5

Positive:
- Increases buffering capacity of blood - neutralising effects of lactic acid and hydrogen ions
- Delays fatigue
- Reduces acidity in muscle cells
Negative:
- Possible side effects: cramps, pain, diarrhoea, bloating, vomiting

Question 6

Positive and negative effects of caffeine

Answer 6

Positive:
- Stimulant - increases mental alertness
- Reduces effect of fatigue
- Allows fat to be used as an energy source - delays use of glycogen stores
- Improves decision making/reaction time
- Benefits aerobic performance - fats used for energy
Negative:
- Loss of fine control
- Against rules in some sports - large quantities
- Possible side effects: dehydration, insomnia, muscle/stomach cramps, diarrhoea, irregular heartbeat, vomiting