Which nutrient is primarily responsible for tissue repair and growth after exercise?

• A. Carbohydrates
• B. Proteins
• C. Fats
• D. Vitamins only

Answer: (B)

Protein is the nutrient most directly tied to tissue repair and growth after exercise. When you train, especially with resistance work, tiny tears form in muscles and connective tissues. Protein provides the amino acids that are used to rebuild and strengthen these tissues, supporting muscle repair and growth. Carbohydrates are important for restoring energy (glycogen) after exercise and supporting overall recovery, while fats supply energy and essential fatty acids, but they don’t provide the primary building blocks for new tissue. Vitamins assist metabolism, but they aren’t the main driver of tissue repair. So, protein best explains why tissues repair and grow after activity.