How much would you pay for a drug that could lower your risks of chronic illness, increase your life expectancy, improve your sex life, minimize your stress and expand your happiness? The good news is that at no cost to you, you can achieve all of those benefits in return for 30 minutes of your time each day. And the “medication” is exercise.
But despite these very well-known advantages, exercise among Americans over the last five decades has declined sharply as the number of jobs that involve intense physical activity has shrunk from 50% in 1960 to 20% today, and the time we spend in front of TV and computer screens has grown dramatically.
As a result, obesity and chronic illness in the U.S. have steadily risen and reached epidemic proportions.
As an avid runner and skier, I am addicted to exercise and its benefits. And as a physician, I routinely encourage patients to engage in physical activity. Two years ago I provided five steps to ease into a healthier lifestyle, and many readers told me how exercise had positively impacted their lives. The benefits of physical activity are so great that we in Kaiser Permanente have made “Exercise a Vital Sign” a signature initiative and encourage all patients at each visit to begin a program.
Now that spring has arrived, bringing more daylight and higher temperatures, people can more easily venture outside and be active. So now is an opportunity to focus on fitness and health. This week’s column reviews the benefits of exercise and provides one approach–admittedly, mine–for an exercise regimen.
Five Key Benefits
- Cardiovascular health
The heart is a powerful muscle that pumps blood to the rest of the body, and exercise strengthens the heart. Exercise cuts the risk of heart disease by raising “good” cholesterol (high-density lipoprotein, or HDL) and reducing unhealthy fats (triglycerides) in our blood, helping to prevent blood vessel blockages that could result in a heart attack or stroke.
- Weight management
There is a direct correlation between calories taken in, calories burned and weight gain or loss. In general, if we consume 3,600 calories more than we burn, we gain a pound, and when the opposite happens, we lose a pound. The average-sized adult male burns 100 calories for every mile covered, slightly more if he races, while the typical female burns slightly less per mile due to a smaller body mass. Walk, jog or run a mile and you burn approximately 100 calories. As a result, run three miles a day, five days a week, and you will lose over 10 pounds per year, provided your calorie intake stays the same.
The advantages of avoiding excess weight are many, beginning with reducing the chance of developing adult-onset diabetes. With increasing amounts of fat, the cells of the body become relatively resistant to the hormone insulin, which facilitates the delivery of sugar from the blood into the tissues. When the pancreas can’t produce enough insulin to overcome the relative resistance to insulin, the level of blood sugar or glucose rises. High levels of glucose in the blood are toxic, damage blood vessels and nerves and lead to many of the symptoms of diabetes. Patients with diabetes have an increased risk of heart attack, kidney failure, blindness and loss of blood circulation to the feet, potentially leading to amputation. When patients develop all three–elevated blood lipids, diabetes and hypertension–the combination can be lethal. And exercise can prevent and reverse all three.
- Increased happiness and energy
When we exercise, our brains release a chemical called endorphin that makes us feel good, increases our optimism and diminishes the sensation of pain. The experience of euphoria produced by release of endorphins is often referred to as “runners’ high.”
For millennia, life and death were determined by the level of stamina our ancestors demonstrated, and whether they could hunt even when tired and discouraged. As such, the release of this powerful brain chemical had major survival benefits. Even though we don’t hunt for survival today, exercise can produce the endorphins that help us overcome the stresses of life.
Starting each day with a three-mile run, half-hour bike ride or 30 minutes of fast-paced walking helps us feel more energetic, less depressed and more optimistic for hours to come. And when we feel positive, we are more likely to be successful at fulfilling our potential and meeting our goals in life.
The benefits are a bonus. As our heart and lungs become stronger and more efficient at oxygenating our blood and pumping it to the tissues of our body, we feel better and stronger. And the exercise we do during the day helps our natural biorhythms kick in at night. We doze off more easily and have a deeper, more restful sleep. For older individuals, weight-bearing exercise helps prevent frailty, preserves bone mass and reduces falls. And growing evidence shows that exercise diminishes the likelihood of decreased cognitive function as we age, and may significantly lower the odds of developing Alzheimer’s disease.
- Improved intimacy
Regular exercise contributes in many ways to intensifying sexual pleasure. It boosts energy and stamina. It tones your muscles, and as a result, improves the appearance of your body. And it can combat the likelihood of erectile difficulties in men by helping avoid blockage of the arteries to the penis and increasing pelvic blood flow and arousal in women.
- Expanded social network
Exercise is a great activity to share with friends and strangers alike. Finding a walking, running or biking partner increases the chances you will get out of bed in the morning and make exercise a daily habit. Walkers and runners often describe how conversation flows more easily and friendships grow over time. In most cities and towns, groups of individuals meet in the morning or after work to walk, bike, run or play a variety of sports.
The benefits of exercise correspond mainly to the amount of time during which your muscles are being used and your heart is beating faster than normal. Although high-intensity exercise has the greatest impact, any exercise with sustained elevation of heart rate proves effective. In fact, the biggest advantage of running fast, rather than jogging, comes from the added distance covered, rather than the added speed itself. For this reason, if you don’t enjoy running or biking, then you can dance, play tennis, golf (walking rather than riding in a cart) and do aerobics. If you have lower extremity joint problems, swimming is a great option. And of course those who prefer yoga reap the benefits of exercise combined with meditation.
Individuals who are healthy can safely begin an exercise program at any time. For those with cardiovascular disease or diabetes, and people taking multiple medications, checking with a physician first is prudent. As a physician and experienced runner, I enjoy helping others discover just how much exercise can improve their health.
If you decide to start an exercise program, I recommend a combination of walking and running. When it comes to time efficiency, this approach burns the most calories and improves cardiovascular function in the least amount of time each day. And as stamina increases, and more distance is covered in the same number of minutes, the benefits rise proportionately.
Thirty minutes of exercise, five days a week, is a great place to start. In half an hour, most walkers can cover a mile and a half, and by adding intermittent jogging, the distance quickly grows to two miles. As muscles become stronger, endurance increases, jogging becomes running, 30 minutes stretch to 50 and the health benefits expand significantly. A recent study in the Journal of the AMA (JAMA) demonstrated that life expectancy increases dramatically at this level compared to sedentary individuals, although the benefits don’t peak until approximately 7 hours a week.
I use a health app on my smart phone to track distance covered and my total number of steps. For people beginning an exercise program, 10,000 steps a day serves as a laudable goal. For those who don’t want to carry their phone with them on runs, there are many monitoring tools you can buy and wear on your wrist.
A general rule if you want to maximize the results of your exercise regimen is to add about 10% more distance per week. This can be accomplished by quickening the pace, logging more time or both. Depending on where you exercise, you can measure the increased distance by blocks covered, laps completed on the neighborhood track or total minutes spent. And of course, any way you measure it, your steps will go up in parallel.
Here’s a fact that should fuel your motivation: The longer you maintain an exercise program, and the more you do, the easier it becomes. And as you experience its benefits, you’ll feel inspired to do even more. This is often referred to as a “virtuous cycle.” But if we do the opposite–skip exercise, gain weight, lose energy and cardiovascular fitness–we create a “vicious cycle.”
Our bodies evolved from thousands of years of daily exercise as we survived through hunting and gathering. As a result, we are genetically programmed to benefit from daily activity. So this spring make the commitment. If you can exercise five days a week for three months, it will be a habit you are unlikely to break. And the only question you’ll ask yourself will be why it took you so long to get going.
This article appeared on 4/14/16 on Forbes.com