Protein - daily protein needs for athletes

Question 1

How does protein synthesis change with exercise?

Answer 1

With exercise: variations in protein synthesis are greater in the fed state and decline less in the fasted state

Question 2

When is exercising muscle most sensitive to protein synthesis?

Answer 2

Exercising muscle most sensitive during early phase of post exercise recovery.

However responses after this are still far higher than if no exercise is performed

Question 3

When is protein synthesis at its greatest: rest, rest + AA feeding, resistance exercise, resistance exercise + AA feeding?

Answer 3

resistance exercise + AA feeding = greatest anabolic stimulus

Question 4

What % of proteins do myofibrillar proteins make up?

Answer 4

65% - however they have a relatively low FSR (low protein turnover)
- turns over between 1-2% per day
- equates to 300-600g of muscle protein

Question 5

How do mitochondrial proteins differ to myofibrillar proteins?

Answer 5

Lower % (5-10) make up overall protein content. Much Higher FSR (high protein turnover rate).

Question 6

In terms of the synthesis of proteins, how does resistance and endurance exercise differ?

Answer 6

Resistance exercise increases synthesis of force producing proteins.

Endurance exercise increases synthesis of energy producing proteins.

Question 7

What is the estimated average requirement and recommended dietary allowance of protein intake?

Answer 7

EAR = 0.66g/kg bw
RDA - 0.8g/kg bw

Question 8

How does exercise effect MPS?

Answer 8

1. Demanding exercise stimulates a prolonged elevation of muscle protein synthesis (MPS).
2. In the post-exercise period, the MPS response to protein ingestion is enhanced.
3. This augmented fed-state MPS response may persist for 1-2 days post-exercise

Question 9

What is the optimal protein dose for MPS in Young healthy Adults?

Answer 9

0.24 g/kg
Amount of protein consumed relative to bodyweight - protein synthesis response measured.

Question 10

Daily protein requirements are even higher during post-exercise recovery vs rest, what are they?

Answer 10

~2.0 g/kg/day maximised whole-body anabolism in resistance trained men after exercise

~2.5-fold higher than the
current RDA

Question 11

How are Daily Protein Requirements Higher than Current Recommendations for Endurance Athletes?

Answer 11

The mean EAR and upper 95% CI (approximating the RDA) protein requirement were 2.1 and 2.6 g/kg/day,
respectively.

~3.2-fold higher than current EAR and RDA