Nutrition plays an important role in increasing muscle strength through fueling exercise and promoting recovery and exercise-induced adaptations. These processes are mainly influenced by protein and carbohydrate intake. Evidence suggests that a total daily protein intake of about 1.6 grams per kilogram of body weight is ideal for supporting increases in strength.[1][2]
Muscle glycogen is a primary fuel source during resistance exercise,[3] and glycogen depletion is associated with muscle fatigue and impaired muscle contraction efficiency,[4] so consuming at least 3–5 grams of carbohydrate per kilogram of body weight per day is recommended to maximize strength gains.[1]
With that said, many studies have not found differences in strength gains between higher- and lower-carbohydrate diets,[5] particularly when the resistance exercise routine includes low volumes (< 10 sets per workout), high loads (≥ 80% of 1-repetition maximum), and long rest periods (≥ 3 minutes of rest between sets). However, there is a lack of evidence demonstrating benefits of lower-carbohydrate diets for muscle strength.