After strength training, a whey protein shake can help kick-start muscle recovery. When you get done with a run, carbohydrates help replace the energy your body used to fuel the effort. A study published in the International Journal of Sport Nutrition and Exercise Metabolism looks at how both nutrients affect fat oxidation.
Twelve recreationally active women took part in an incremental 23 minute bike ride where the effort ranged from 30% to 80% of maximal oxygen consumption. Then they exercised for an hour at 75% of capacity. After this workout, subjects received 20 grams of protein, 20 grams of carbohydrates or a placebo.
Whole body fat oxidation doubled during the second trial and the rate of fat oxidation while subjects were at rest wasn’t significantly different between protein and placebo conditions. Carbohydrate consumption did reduce the increase in fat oxidation after exercise.