The Importance of Protein for Muscle Growth Protein is an essential macronutrient for muscle growth and repair. Whether you’re trying to build muscle, improve strength, or recover from an intense workout, protein plays a vital role in the process. In this article, we’ll delve into why protein is so important for muscle growth and how to ensure you’re getting enough. 1. Supports Muscle Repair and Growth After you exercise, your muscles experience tiny tears, and protein helps repair and rebuild these fibers.