From birth to old age, our bodies are continually changing. When we put off regular exercise, our bodies are not just frozen in motion, they’re fading. Physical activity stimulates most organs to work at their best. We are made to move, and if we don’t, all systems of the body are affected, right down to the cellular level where our ability to transfer oxygen for energy can be diminished. Inactivity impacts the brain, muscles, heart, blood vessels, bones, liver, gut, sleep, anxiety, depression, self-esteem, and the ability to use glucose (to name a few).
Prolonged Physical Inactivity Can
Contribute to Many Health Problems
Insulin sensitivity deteriorates with inactivity. Type 2 diabetes is characterized by the body’s inability to utilize the insulin it produces. The cells of the body become insulin-resistant. Insulin carries sugar from the blood into the cells of the body. Without the ability to do this, blood sugar levels rise and diabetes develops.
Type 2 diabetes is a sedentary disease. Regular exercise reverses the damage. Insulin sensitivity increases with exercise and the cells become better at taking in and processing glucose.
The impact of activity on diabetes is striking. Every two hours per week of watching TV is linked to a 14% increase in the risk of diabetes. Conversely, every hour of brisk walking per week confers a 34% lower risk of developing diabetes. That’s something to think about the next time you are too tired or busy to put on your athletic shoes.
Exercise affects the heart in several ways. Not only does it strengthen the pump, but it also impacts the pipes. In recent years, researchers have discovered that physical activity makes the lining of blood vessels more flexible, from the largest artery to the smallest capillaries. This allows blood vessels to relax, permitting more blood to be sent to the heart. Think of it in terms of pumping blood through a rubber hose instead of a concrete pipe. This is particularly important where vessels are partially blocked.
Regular exercise also increases HDL (good) cholesterol. This type of cholesterol passes through the arteries instead of sticking to them. For those who already have heart disease, exercise can lower your risk of dying from it. Take that to heart!
Active people are 25% less likely to suffer a stroke than sedentary folks. Exercise affects the arteries to the brain in the same way as the heart. Most strokes occur when a blood clot gets stuck in a partially blocked artery leading to the brain. Hemorrhagic stroke occurs when a blood vessel in the brain bursts. High blood pressure is a risk factor for any type of stroke. Regular aerobic exercise can lower blood pressure significantly.
The metabolic cost of maintaining muscle is high. Muscles require a lot of energy, so if you don’t use them, they become a luxury for the body to maintain. If you don’t use it, you lose it. As we age, we become increasingly inactive and lose muscle mass. But we can rebuild muscle with strength training. The earlier you start, the better. Even those of advanced age can benefit from carefully pumping a little iron. Strong muscles can help to prevent the frailty that makes older people lose their independence. Regular exercise is one way to stay out of a nursing home.
Inactivity and weight gain go hand in hand. When you lose your muscle mass because of inactivity, you need less energy (calories) to maintain what is left. Because of inactivity, it becomes possible to gain weight with a modest calorie intake but nearly impossible to lose weight. The rate of weight gain may be slow, perhaps 1-5 pounds a year, but over 10 years, the pounds add up and the loss of physical fitness is significant.
In order to avoid becoming overweight or obese, 45-60 minutes a day of physical activity is needed. If you’re already overweight or have lost a lot of weight, you need more – between 60-90 minutes of physical activity per day to avoid regaining weight. If this seems daunting, just 30 minutes of exercise a day is enough to reduce the risk of many chronic diseases without significant weight loss.
Bones are living tissue. Every day, minerals move in and out of our bones in response to the demands of daily living. If you stress bone, it responds. If you don’t, the balance between bone gain and loss shifts toward loss. Research shows that strength training preserves bone better that walking or running, and it can increase bone density. The amount that a bone is stressed, or overloaded, determines whether bone formation is stimulated. A small number of repetitions (8-15) with a heavy load can do the trick.
Regular physical activity has also been shown to prevent certain types of cancer, depression, dementia, and improve immunity. If exercise were a pill, it would be called a wonder drug.
To reduce health risks associated with inactivity, at least 30 minutes of moderate-intensity aerobic exercise five days a week or 20 minutes of vigorous aerobic exercise three days a week are required. To maintain less weight, 60-90 minutes a day of exercise is needed. To build muscle and prevent bone loss, you need strength training at least twice a week.
The good news is that it is never too late to start exercising. People well into their 90s can benefit from regular physical activity. And if you’ve been moving all along, you can reach your 90s with vitality and independence. The only “magic bullet” out there that I know of is physical activity. So commit yourself to exercise. Schedule it in your date book. As a well known athletic company says, “Just do it!”
Carol Plotkin, MS, RD, CDN, ACSM is a Registered Dietitian as well as a health- and fitness instructor. She is the owner of On Nutrition, a nutrition practice in upstate New York. As a speaker and writer she feels passionate about communicating the facts of healthy nutrition. She contributes to various blogs and other publications.
The articles written by guest contributors are the sole responsibility of the individual writers in terms of factual accuracy and opinion and do not necessarily reflect the views of the publisher of this blog.