Table 2.
A
meal containing carbohydrates, fats, and protein should be consumed
roughly 3-4 h prior to competition to allow for digestion and for a
maximizing of endogenous energy stores. Glycogen stores can be enhanced
with a carbohydrate beverage (1-2 g CHO/ kg) approximately 1 h prior;
this also helps to supplement energy stores and provide adequate fluids
for hydration. A beverage containing 6% simple sugar (i.e., sucrose,
fructose, glucose) provides optimal absorption compared with other more
concentrated beverages such as juice or carbonated drinks that delay
gastric absorption and cause stomach upset. Nutritionally complete
snacks that contain fat and protein may be effective in preventing
late-onset postexercise hypoglycemia if they are consumed immediately
after the activity .
In general, approximately 1.0-1.5 g CHO/kg
body weight/h should be consumed during exercise performed during peak
insulin action in young adults with diabetes. As mentioned above,
tables of exercise exchanges that estimate carbohydrate utilization may
be helpful in determining the carbohydrate intake regime for younger
individuals. To treat hypoglycemia, 15 g is recommended and a retest of
blood glucose level is needed prior to resuming exercise. Carbohydrates are not only required for energy during activity but also
to replace the energy derived from liver and muscle glycogen stores.
Because insulin sensitivity remains elevated for hours postexercise,
carbohydrate stores must be replenished quickly to lower the risk of
hypoglycemia during the first few hours postactivity. For patients who
tend to experience postexercise, late-onset hypoglycemia during the
night, a complex carbohydrate (e.g., uncooked corn starch), or a mixed
snack containing fat and protein may be particularly beneficial at
bedtime. Fluid requirements have been extrapolated from adult needs
and are estimated to be approximately 1.6 L/d for basic requirements
and an additional 0.5-1 L/h of vigorous physical activity. In warmer
environments, fluid requirements are higher for youth as they
experience greater heat accumulation and they perspire less than adults
do. Those with diabetes may be at particular risk because a prior bout
of hyperglycemia reduces body fluid levels.