DEAR DR. BLONZ >> I go to the gym a few times a week with a routine that includes weights and time on the Stairmaster. The word at the gym is that protein needs are especially important for those doing workouts. Aside from the protein, are there any additional nutritional requirements for one such as myself?

W.J., Chicago, Illinois

DEAR W.J. >> The nutritional needs of athletes include supplying raw materials for building and maintaining muscles and providing the energy and nutrients for the muscles to perform. Intensive muscle building or endurance events can increase protein requirements, but given the high protein consumption common with athletes, few will have to add more to meet their needs. In fact, excess protein converts to fat, causing dehydration, an increased load on the kidneys and the loss of calcium in the urine. Despite this, protein supplements with alluring pictures of bulging muscles remain prevalent in gym culture.

Food remains the best source of nutrients. Those who opt for a balanced and varied selection of protein-rich foods and complex carbohydrates from all the food groups will have little difficulty meeting their nutritional needs. Athletes should rely on carbohydrates as a main energy food. Complex carbohydrates from vegetables, grains, fruit, breads and pasta provide a steady energy supply, so these are preferred over simple sugars such as glucose or sucrose.

Athletes and other active individuals should also resist overdoing it with fat-laden fast foods. Nuts, seeds and dried fruits make a great snack food because aside from being low in saturated fat, they provide vitamins, minerals, fatty acids and fiber.

Research has shown that intense exercise will slightly increase the demand for some vitamins and minerals. The body’s supply of iron, the most common nutritional deficiency in the country, is further drained by the demands of endurance exercise. The best food sources of iron include lean red meat, dark green leafy vegetables and iron-fortified cereals.

Calcium and magnesium, needed for muscle work as well as the health of the bones, are also traditionally low in the American diet. There are reports of bone thinning and osteoporosis in runners and older athletes. Athletes who don’t eat dairy products may be at greater risk. Aside from dairy products like milk, cheese and yogurt, calcium can also be found in greens, such as collards and kale, almonds, chickpeas and tofu.

Finally, water is key in any discussion of athletic performance. Water keeps the body cool via perspiration and shuttles waste products from the body through the urine. Even mild dehydration impairs performance and can cause the body to overheat. Because one’s awareness of thirst can be lost during exercise, it’s best to make drinking water a central part of any workout routine.

Kensington resident Ed Blonz has a PhD in nutrition from UC Davis. Email him at cctimes@blonz.com.