The best-known use of whey protein supplements is for the purpose of increasing muscle mass and strength.

Whey protein is popular among athletes, bodybuilders, fitness models, as well as people looking to improve their performance in the gym.

The ways by which whey protein promotes muscle/strength gain include:

1. Building blocks: It provides protein and amino acids, which serve as building blocks for increased muscle growth.
2. Hormones: It increases the release of anabolic hormones that can stimulate muscle growth, such as insulin
3. Leucine: It’s high in the amino acid leucine, which is known to stimulate muscle protein synthesis at the molecular and genetic level 
4. Fast absorption: Whey protein is absorbed and utilized very quickly compared to other types of protein

Whey protein has been shown to be particularly effective at increasing muscle growth when consumed right before, after or during a workout. Muscle protein synthesis is usually maximized in the time period after training