When you eat protein after working out, your body uses it to help repair and rebuild the tough tissues in your muscles while you sleep — and exercising makes this process work even better.

Working out in the evening helps your body use protein from food more effectively to repair and rebuild muscle overnight—almost 60% better than just resting.

For older guys who work out with weights, eating protein after exercise helps their body use it better overnight to repair and build muscle tissue while they sleep.

Lifting weights helps your muscles rebuild their internal support structure while you sleep by boosting protein production in the connective tissue inside the muscle.

For older guys who work out and eat a protein shake before bed, their bodies build more connective tissue in muscles overnight than if they just had the shake or did nothing.

Eating 20 to 40 grams of protein before bed might help your muscles repair and grow overnight, especially if you also worked out in the evening.