Please choose the correct ending to complete the given sentence: Health: [header] How to understand the impact of carbohydrate loading [title] Know when to carbohydrate load. [step] For carbohydrate loading to have an impact, you must be doing an endurance activity lasting longer then 90 minutes. The muscles typically store enough energy for 60 to 90 minutes of activity.

Ending1: [substeps] Exercising regularly can have a lasting impact on the body because it puts more energy into the muscles on the break from a long day. The endurance of an activity allows the bones to regenerate in response to lack of carbohydrate by regulating the blood supply to the body. Ending2: [substeps] Carbohydrates include fat, muscle fibers, eggs, cheese, nuts, and fruits and vegetables. Monounsaturated fats help maintain our body's electrical power, which keeps our brain active. Ending3: With carbohydrate loading you should have enough energy to last more than 90 minutes without fatigue. [title] Understand how carbohydrate loading impacts performance. Ending4: If the recommended number of calories is low, you can stay more stable throughout the day by doing a vigorous exercise. Wait around 15 minutes to rest your muscles and avoid burning out.

Answer format: ending1/ending2/ending3/ending4