To prepare for the cross-country meet, a skier decides to significantly increase the amount of carbohydrates in his diet (a technique also known as carbohydrate loading). Why might this be beneficial to the cross-country skier? Check all that apply. Carbohydrates are used to build actin filaments in the myofibrils, which increases muscle bulk and performance. The liver can store copious amounts of ingested carbohydrates as glycogen, which can then be slowly broken down to release the glucose needed to fuel aerobic respiration. As long as oxygen is present, the glucose stored in the ingested carbohydrates can provide a steady stream of ATP, thus meeting the demands of prolonged periods of exercise. Eating more carbohydrates leads to more glycogen stores in muscles, which then equates to larger energy stores for short, explosive bouts of energy use.