Descending colon. The colon is part of the large intestine, the final part of the digestive system. Its function is to reabsorb fluids and process waste products from the body and prepare for its elimination.The colon consists of four parts: descending colon, ascending colon, transverse colon, and sigmoid colon.escending colon. The colon is part of the large intestine, the final part of the digestive system. Its function is to reabsorb fluids and process waste products from the body and prepare for its elimination.
The USDA's Recommended Dietary Allowance (RDA) for protein is .8 grams per kilogram (or .36 grams per pound) of body weight. But that's not enough for athletes, according to the ISSN, which says endurance athletes like runners need 1.0 to 1.6 grams per kilogram a day (or .45 to .72 grams per pound).
Foods are made up of carbohydrates, protein, and fat. Marathon runners and athletes in general should eat a diet high in carbohydrates, moderate in protein, and low in fat. Another key nutrient that is a must for athletes is water.ndurance athletes need up to 50% more protein than sedentary adults. Protein should contribute 12-15% of total calories per day. To figure out the amount for you, multiply your weight in kilograms by 1.3, or multiply your weight in pounds by 0.6 to calculate the number of grams of protein you should consume per day.