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After swimming, rats that drank whey protein had more leucine inside their muscles than those drinking other proteins for up to 1.5 hours after eating.
Descriptive
After swimming, rats that drank whey protein had more leucine in their blood than those drinking other proteins at 1 and 1.5 hours after eating.
When rats ate more milk protein up to a certain amount, their muscle building increased, but eating even more didn't help further.
When measuring overall muscle building over several hours, milk protein showed the highest total effect, then caseinate, whey, and soy, but the numbers weren't statistically tested.
When rats swam for two hours and consumed dairy proteins (whey, milk, or caseinate), their muscle building rates were higher than those eating soy protein at specific times after eating.
When rats swam for two hours and then consumed caseinate, their muscle building rate peaked at 120 minutes with a value of 7.85% per day.
When rats swam for two hours and then consumed milk protein, their muscle building rate peaked at 90 minutes with a value of 8.34% per day.
When rats swam for two hours and then consumed whey protein, their muscle building rate peaked at 60 minutes with a value of 7.76% per day.
Experienced weightlifters lose over half their protein retention per body weight when delaying protein and carb intake after a workout, but beginners aren't affected much by the timing.
Quantitative
For experienced lifters, eating protein and carbs right after a workout leads to better protein retention per pound of body weight than waiting six hours, but this isn't the case for beginners.
Experienced weightlifters retain less protein in their bodies after workouts compared to beginners, regardless of when they eat protein and carbs.
For men new to weightlifting, eating protein and carbs right after a workout or waiting six hours doesn't change protein retention in the body.
For men who regularly lift weights, eating protein and carbs right after working out leads to better protein retention in the body compared to waiting six hours.
Causal
Neither type of whey protein affected insulin levels in rats' blood an hour after exercise, regardless of dose.
Both types of whey protein at a higher dose activated the mTOR pathway in rats' muscles compared to no protein.
A larger dose of regular whey protein activated a key muscle-building pathway more than hydrolyzed whey protein or no protein in rats.
When rats ate a larger dose of regular whey protein, their blood had more leucine than when they ate the same amount of hydrolyzed whey protein an hour later.
Correlational
For rats, the best time for muscle protein building after eating regular whey protein is about an hour later.
A small dose of whey protein hydrolysate made a key muscle-building signal stronger in rats than regular whey protein or no protein.
When rats exercised and then ate a small amount of whey protein hydrolysate, their muscles built protein faster than when they ate regular whey protein at the same dose.
Vegan men who don't exercise much and have been vegan for a year lose protein when eating the standard protein recommendation for 5 days.
Based on the protein loss observed, vegans might need about 20% more protein (0.96g/kg/day) to stay balanced.
The standard protein recommendation for adults (0.8g/kg/day) isn't enough to keep protein levels stable in men who've been vegan for a year and aren't very active.
For these vegan men, how long they'd been vegan, their age, muscle mass, or activity level didn't affect whether their bodies were losing protein on this diet.