Let’s start with an indisputable fact: exercise is good for you. Period.
It can help you fight certain diseases and health conditions, control your weight, improve your balance, brighten your mood, boost your energy, and put the zing back in your love life. Building strong muscles and bones can help you maintain your independence as you age. There’s also medical evidence that exercise can help boost your immunity, which naturally declines as you grow older.
Chronic lower respiratory disease is among the three leading causes of death for people 65 and older, according to the Centers for Disease Control. On average, most adults get two to three upper respiratory infections a year. David C. Nieman, DrPH, director of the Human Performance Labs at the North Carolina Research Campus, is a respected expert on the impact of exercise on the immune system. Through decades of research, Nieman has determined that regular moderate exercise can help improve immunity, leading to fewer infections.
In addition to helping support the skeleton system, the muscular system pumps blood and lymph throughout the body, circulating the cells—lymphocytes—that attack the cause of infections. Bone marrow and the thymus produce B- and T-lymphocytes which move to the spleen and eat bacteria and viruses as blood passes through the organ. The body then flushes out the invaders through urination. The older you are, the fewer B- and T-cells your body will produce, thus decreasing your ability to fight off infections. Keeping the circulation of the lymphocytes moving through exercise helps increase the immune system’s effectiveness as you age.
Interestingly, working out too hard can have the opposite effect. Through his research, Dr. Nieman has established that intense exercise depresses the immune system, at least temporarily, causing increases in respiratory infection rates. Writing in Nature, Dr. Nieman, who holds a doctorate in public health, said “many components of the immune system exhibit adverse change after prolonged, heavy exertion.” Tests on urine and blood samples from athletes and non-athletes, before and after intense exercise, confirmed changes in immunity protection in the upper respiratory tract, the lungs, the skin, blood, and muscle.
The changes cause a window of opportunity—anywhere from three to 72 hours—when the person exercising intensely is most vulnerable to viruses and bacteria. Dr. Niemen said the risk of infection is even greater during this period if the person is under severe mental stress, lacking sleep, and/or eating poorly. According to another study that Dr. Nieman conducted, the impact on the immune system from the intense workout was the same regardless of whether the person was doing cardiorespiratory exercise or resistance training, such as leg squats.
Moderate exercise—weightlifting or aerobic—is the way to proceed if you want to boost your ability to fight off viruses and bacteria before they take hold. The World Health Organization recommends at least 150 minutes of moderate aerobic exercise a week for adults. WHO suggests that be bolstered by muscle-strengthening exercises involving major muscle groups at least twice a week. As always, check with your doctor before starting any exercise program.
If you want more advice on how to protect yourself from the flu and colds, check out the CDC’s website here: www.cdc.gov