DEAR DR. BLONZ: How do the nutritional needs of an older athletic individual -- that's me -- differ from one who has chosen a sedentary lifestyle? My lifelong friend, who happens to be the same approximate height and weight, doesn't do much exercise, and I keep trying to encourage him to get with the program, but he doesn't see the upside. -- F.L., Walnut Creek, California
DEAR F.L.: There is a big difference in how contrasting lifestyles impact the body, so don't think that the fact that you and your friend might wear the same size clothes be viewed as a pass for his non-active lifestyle. As for nutritional requirements, those for the average older athlete will be similar to those of an individual who is sedentary, with two exceptions: water and calories. Both require a varied diet that focuses on nutrient-dense fruits, vegetables, grains, nuts, seeds and dairy products, with a modicum of high-protein foods such as fish, poultry and meat.
The body's metabolism goes through radical changes as we progress through mid-life into our senior years. The need for dietary calories decreases because of the continually decreasing calorie-burning capacity of our cells. In addition, the digestive system, through which nutrients are digested and absorbed, gradually becomes less efficient. The ability to feel thirst also tends to diminish, resulting in an inadequate water intake.
The body's skeleton shifts into "negative balance." This is where the removal of minerals, such as calcium from the bones, proceeds more rapidly than they can be replaced. The net result is a gradually weakening bone structure and an increased risk of osteoporosis. A sedentary lifestyle allows all these changes to proceed unabated. When you're active, though, the body behaves differently.
Because muscle movement is required during exercise, the calorie-burning capacity of our cells does not decrease as rapidly. The bones need to retain more strength so less of their precious minerals will be lost. The joints will tend to retain more flexibility to help support the physical activity. Circulation, needed to provide fuel to the working muscles, improves, and the heart muscle tends to remain stronger. In essence, activity, even if it's only regular daily walks, will help to keep you younger, longer.
Water is especially essential before, during and after exercise because it helps to keep the body cool via perspiration. In addition, water helps to shuttle waste products from energy production out of the body through the urine. Dehydration, even when mild, impairs performance and can cause the body to overheat and malfunction. This can be especially dangerous in the older athlete because the kidneys do not operate as efficiently. Because one's awareness of thirst can be lost during exercise, it's best to make drinking water a part of any exercise routine.
I am hopeful that your friend will be able to grasp the big picture that activity should be considered an investment that is especially important for seniors. It not only affects the quality of our day-to-day lives and capabilities, but it bolsters the resilience with which we are able to handle the inevitable curveballs that life throws our way.
Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to email@example.com. Due to the volume of mail, personal replies cannot be provided.