18a. Sports Nutrition - Energy

Question 1

What are the key goals in sports nutrition?

Answer 1

Energy and stamina
Build/maintain strength
Adaptation
Immunity
Recovery
Focus and concentration

Question 2

Why are energy and stamina important in sports nutrition?

Answer 2

Spare muscle glycogen and protein
Keep body fuelled for longer

Question 3

Why is adaptation important in sports nutrition?

Answer 3

Training the body to perform better with less
Perform in adverse conditions

Question 4

What is maximal performance?

Answer 4

Races/events
When the person wants to be the best they can
Setting PBs
All out

Question 5

What is training?

Answer 5

Regular practice to allow the person to get better
Stimulate race conditions

Question 6

What are the two types of energy systems?

Answer 6

Anaerobic (high intensity)
Aerobic (high volume)

Question 7

What does the anaerobic energy system consist of?

Answer 7

Phosphate energy system
Lactate energy system

Question 8

What is the phosphate energy system?

Answer 8

Uses phosphocreatine as fuel
For bursts of speed up to 6 seconds duration
Produces no waste products

Question 9

What is the lactate energy system?

Answer 9

Uses stored muscle glycogen and serum glucose only
Lasts 30 secs at 95% intensity
Lasts 30 mins at 60% intensity
Produces lactic acid as a by-product

Question 10

Where is creatine produced?

Answer 10

Liver

Question 11

Which amino acids is creatine produced from?

Answer 11

Glycine
Arginine
Methionine

Question 12

What happens to creatine once made?

Answer 12

Transported to muscle cells
Combines with phosphate to produce phosphocreatine

Question 13

Where is phosphocreatine stored?

Answer 13

Muscles
(so it can be quickly used for max energy)

Question 14

How is phosphocreatine used for energy?

Answer 14

Phosphate and creatine bond broken down
Phosphate used to regenerate ADP/ATP

Question 15

How much creatine can be stored in muscles?

Answer 15

Up to 120g

Question 16

What happens to free, unstored creatine?

Answer 16

Recycled into more PC
Converted into creatinine which is excreted in the urine

Question 17

What happens during the lactate energy system?

Answer 17

Without oxygen, glucose conversion halts at pyruvate
Excess is converted into lactate
Lactate is reconverted into glucose via liver

Question 18

What can compromised lactate energy conversion lead to?

Answer 18

Reduced energy recycling
Poor cognitive performance during exercise

Question 19

When is the aerobic energy system used?

Answer 19

When oxygen supply and usage matches energy demand
(glycolysis, Kreb cycle, ETC)

Question 20

Which energy system does the body switch to when oxygen demand is succeeded?

Answer 20

Anaerobic

Question 21

Which fuel source does the aerobic energy system mostly use?

Answer 21

Carbs
Lipids

Question 22

What type of exercise mostly uses anaerobic energy?

Answer 22

Long distance
High volume events

Question 23

What are the major fuels used for short bursts of activity lasting less than 6 secs/high intensity lasting up to 30 secs? (strength training/HIIT)

Answer 23

ATP
Phosphocreatine

Question 24

What are the major fuels used for high intensity activity lasting up to 15 mins?

Answer 24

Muscle glycogen

Question 25

What are the major fuels used for mod-high intensity activity lasting 15-30 mins? (5K run)

Answer 25

Muscle glycogen
Adipose tissue

Question 26

What are the major fuels used for moderate intensity activity lasting longer than 60 mins? (long run/marathon)

Answer 26

Muscle glycogen
Liver glycogen
Blood glucose
Intra-muscular fat
Adipose tissue

Question 27

What does VO2max measure?

Answer 27

Oxygen uptake to skeletal muscle

Question 28

What is VO2max measured by?

Answer 28

ml/kg bodyweight/min

Question 29

What can a higher VO2max do in terms of energy systems?

Answer 29

Longer aerobic energy production

Question 30

Which energy store is used for anaerobic high intensity exercise e.g. sprinting, lifting heavy weights, burst of energy?

Answer 30

Muscle glycogen

Question 31

Which energy stores are used for aerobic moderate intensity exercise e.g. steady jog/swim?

Answer 31

Muscle glycogen
Lipids

Question 32

Which energy store is used for aerobic low intensity exercise e.g. walking, yoga?

Answer 32

Lipids

Question 33

What happens to muscle glycogen as the duration of the exercise increases?

Answer 33

Decreases

Question 34

What energy fuel kicks in during a long period of exercise as muscle glycogen utilisation dips?

Answer 34

Lipid catabolism

Question 35

What does aerobic training increase?

Answer 35

Fat-oxidising enzymes
Number of capillaries supplying muscles
Number of mitochondria within muscle cell

Question 36

What does the increased number of capillaries supplying muscles during aerobic training do to lipids?

Answer 36

Increases transportation

Question 37

What does the increased number of mitochondria within the muscle cells during aerobic training do to lipids?

Answer 37

Increases utilisation and ATP production

Question 38

Which fuel source is used more during a low carb diet?

Answer 38

Fats

Question 39

What fuel does RBC rely on?

Answer 39

Glucose

Question 40

Which fuels does the brain rely on?

Answer 40

Glucose
Ketones

Question 41

Which fuels does adipose tissue rely on?

Answer 41

Glucose
Fatty acids

Question 42

Which fuel does the liver rely on?

Answer 42

Fatty acid

Question 43

Which fuels do muscle cells rely on?

Answer 43

Glucose
Fatty acids
Amino acids

Question 44

Which fuels does cardiac muscle rely on?

Answer 44

Fatty acids
Ketones