Answer to Question 1
Without enough energy to meet the added demands of physical activity, an athlete can lose muscle and hence strength and endurance.
Answer to Question 2
Carbohydrate loading is used to promote an increase in glycogen stores for additional fuel usage during competitive events lasting longer than 1 hour. Carbohydrate loading is accomplished in a two-stage process. During the first stage athletes must consume enough carbohydrates to replenish and maintain stores while training (6-8 g/kg body weight/day). 1 -2 days prior to competition, athletes should taper work intensity and increase carbohydrate intake by 60 to 10-12 g/kg body weight per day.