Carbohydrate loading is a strategy used by endurance athletes to increase muscle glycogen stores, enhancing performance by delaying fatigue and sustaining higher exercise intensity. This study examines the effects of glycogen depletion and subsequent replenishment to assess how well carbohydrate loading increases muscle glycogen stores for endurance sports. This study measures the amount of glycogen in muscle tissue using sterile containers, muscle biopsy needles, and high-performance liquid chromatography. Participants followed a two-phase regimen: a high-intensity exercise and low-carb diet during the depletion phase and a low-intensity exercise and a high-carb diet during the carbohydrate loading phase. Glycogen levels decreased dramatically during depletion, but according to the results, they increased significantly after loading and exceeded their pre-depletion values. The mechanism of increasing glycogen stores is confirmed by statistical research, which supports its application to increase endurance performance and delay fatigue. This chapter focuses on finding potential physiological benefits by discussing various techniques of carbohydrate periodization across studies.