Older guys who lift weights and take a protein shake after workouts and before bed get the same muscle-building effect as those who take a fake shake with the same calories — so the protein might not...

For older guys who lift weights, having a protein shake with 3 grams of leucine right after workouts and before bed doesn’t help build more muscle or strength than just having a placebo drink with the same calories.

Older guys (60–75) who already eat enough protein don’t get stronger or build more muscle from extra protein shakes, even if they drink them after working out or before bed—just lifting weights is enough.

Drinking a protein shake with casein before bed helps your muscles grow and get stronger while you sleep, especially if you're working out.

For older guys in their 60s and 70s who already eat enough protein, taking 40 grams of protein right after working out or just before bed doesn’t help build bigger leg muscles any more than just working out — the muscle gains are about the same no matter when they take it.

Older adults might need to eat about 40 grams of protein before bed to help their muscles repair and grow overnight, because 20 grams isn’t enough as their bodies become less responsive to smaller amounts of protein with age.