Learn why exercise is vital to mental health, immune-system support and healthy aging, and what types of workout really help you the most.
We all know exercise is good for us. But conversations about exercise often revolve around weight loss—oddly, not one of the health effects exercise is most likely to produce, particularly on its own. If you’re hoping to shed a few pounds, transitioning to and maintaining a healthful, whole-foods diet and reasonable portion sizes is more likely to offer success. But that doesn’t mean exercise isn’t important. On the contrary, physical activity is crucial to our health—both physical and mental—in so many ways that whether we hope to shed a few pounds is irrelevant to whether we should commit to a daily exercise program. Exercise’s most commonly noted health effects often center on our cardiovascular systems: Exercise is key to maintaining heart health; reducing risk factors of heart disease; and reducing risk of death from heart disease (as well as all other causes of mortality). But it also yields many additional benefits. Some 90 percent of Americans don’t get enough exercise. In fact, researchers believe many of the declines we consider a natural part of aging may well be as much from lack of use as from the march of time. In case you need a few good reasons to make exercise part of your healthy lifestyle, consider these health effects.
Cancer Prevention: When it comes to cancer prevention, exercise is highly effective at reducing risk—especially against certain forms of cancer. The key, however, is in intensity: Those who exercise vigorously see a significantly higher protective effect than those who exercise at low intensity. In one study, researchers monitored more than 2,500 middle-aged Finnish men for about 17 years, documenting daily activity levels. After controlling for cigarette smoking, fiber and fat intake, age and other variables, the scientists concluded that the most physically active men were the least likely to develop cancer, in particular of the gastrointestinal tract or lungs. But, according to reporting by The New York Times, the intensity of the activity was key—those who jogged or did similarly intense exercise for at least 30 minutes a day had a 50 percent reduction in the risk of dying prematurely of cancer, while those who strolled and walked saw smaller reductions in risk. Quantity is also important: In the comprehensive 2008 national Physical Activity Guidelines Advisory Committee report, the committee found that one hour per day of moderate to vigorous activity reduced risk of breast cancer more significantly than the 2.5 hours of moderate exercise a week recommended by the surgeon general.
Immunity: Exercise’s ability to reduce incidents of cold, flu and infection is well-documented: In one study of about 1,000 healthy adults, aged 18 to 85, over a 12-week period, those in the top quarter for fitness levels (who exercised five days a week) experienced 43 percent fewer days with upper respiratory tract illness compared with the bottom 25 percent of exercisers. Exactly why exercise may boost immunity is unknown. Some researchers hypothesize that exercise helps increase the diversity of the beneficial microorganisms in the gut, thereby improving immunity—studies have linked exercise with greater diversity in the microbiota. Others believe the immune benefits may be connected with exercise’s positive effects on circulation, while others attribute the increase in wellness to the reduction in stress hormones exercise confers. One caveat: After intense, extended workouts (runs of more than two hours, for example) immune function is temporarily diminished.
Bone Health: It’s important to exercise throughout our lives for bone health. When we’re young, exercise helps us build stronger bones, achieving greater peak bone mass (which occurs in our 20s) than those who don’t, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. After that time, we begin to lose bone every year, but exercise can also help prevent bone loss. Not all exercise boosts bone health, however—exercises such as cycling and swimming, while excellent cardiovascular exercises, don’t help protect the bones because they’re not weight-bearing. Instead, try exercises that make the body work against gravity: weight training, hiking and jogging, tennis, dancing or climbing stairs.
Joint and Back Pain: Exercise also strengthens joints, which can reduce the effects of the degenerative disease osteoarthritis. Although it may seem counterintuitive, exercise helps increase joint flexibility and health—many arthritis patients who start an exercise program report less disability and pain, and also remain independent longer than their inactive peers, according to research reported in The New York Times. Some of the best exercises for osteoarthritis sufferers include strengthening exercises such as weight lifting; range-of-motion exercises such as yoga and tai chi; and low-impact aerobics such as swimming, cycling and walking. Lack of exercise may also increase risk of low back pain for those with chronic pain. Some of the best exercises to maintain strength and flexibility in the back include yoga and tai chi, low-impact aerobic exercise, and the development of strong core muscles. Those with chronic low back pain should be guided by professionals, however, as strenuous activity can also exacerbate back pain.
Balance: Every year, more than a third of seniors age 65 or older fall, and these falls can have serious health impacts when they lead to fractures or concussions. Balancing exercises are important to help maintain health, and they can also make us more agile and thus less prone to injury during other types of exercise. Balance is readily regained with practice, and balancing exercises are easy to do at home. The National Institutes of Health recommends seniors practice balance exercises a few times a week, using a sturdy chair to hold onto. These simple exercises include standing on one foot, walking heel to toe, and doing back and side leg raises. To get a home program for balance, visit National Institutes of Health.
Muscle Loss: Often considered a hallmark of aging, muscle loss can be related to falls and injuries. Muscle loss also makes it harder to do everyday tasks such as climbing stairs and carrying grocery bags. Although some drugs can help rebuild muscle in the severely debilitated (severe muscle loss is known as sarcopenia), researchers say prevention is the best tactic for age-related muscle decline.
Some decline is unavoidable—beginning at age 30 we lose about 1 percent of muscle every year—but researchers are finding that we can significantly slow this decline with weight training. “A 70-year-old active individual is probably younger from a biomarker standpoint—muscle strength, balance, body composition, blood pressure, cholesterol levels—than a 40-year-old inactive individual,” Miriam Nelson, a professor of nutrition at Tufts University, told The Boston Globe. She found in studies that previously sedentary postmenopausal women could increase muscle strength by 80 percent by lifting weights twice a week for a year. Beginning in middle age, everyone should aim to do twice-weekly strength training—weight lifting or bodyweight-bearing exercises such as push-ups, squats and lunges.
However, to build muscle, we also need to consume adequate protein. The government daily recommended allowance for protein is 46 grams for women and 56 grams for men but, according to an article published in The Boston Globe, research is mounting that seniors may need nearly double that amount to avoid accelerated muscle loss. In a 2009 study, researchers found that consuming 25 to 30 grams of protein (the amount in a three-egg cheese omelet or 4 ounces of lean beef) at breakfast boosted the body’s muscle-building rate by 50 percent. But don’t eat all of your protein at one meal—aim to eat a lot of protein in the morning, then consume protein throughout the day.
Exercise is key to mental health and clarity, affecting the way our brains produce and process hormones and chemicals. Exercise even spurs the formation of new brain cells—something scientists had long thought impossible. The mental benefits of exercise can be hard to tease out: Exercise affects so many processes in our brains and bodies, the mechanisms through which it impacts us are often not clear. However, the results are clear: In many cases, a regular exercise regimen can ease symptoms of mental health afflictions as effectively as pharmaceuticals.
Anxiety and Depression: Anxiety and depression are among the most common mental illnesses. Depression, the most common, affects some 25 percent of Americans at some point in their lives. Anxiety disorders affect another 18 percent of Americans. Prescription drugs are the most common treatment—use of prescription antidepressants increased by 400 percent between 1988 and 2008, according to the Centers for Disease Control and Prevention, and more than one in 10 Americans older than 12 takes an antidepressant. Yet multiple studies have found exercise to be just as effective as pharmaceuticals in treating the symptoms of depression and anxiety. A 1999 randomized controlled trial found that an aerobic exercise program improved symptoms in depressed adults as much as the drug Zoloft, reports The Atlantic. A 2006 meta-analysis of 11 studies backed up these findings. Researchers have also found exercise to positively impact the pathophysiological processes of anxiety, with numerous studies and meta-analyses finding exercise to be associated with reduced anxiety. Although researchers can’t be sure of all the ways exercise benefits those with these disorders, one recent study suggests that exercise may calm neurons in the brain. Researchers have long known that exercise can build new neurons. Often these new neurons are predisposed to be easily excited, firing wildly at the slightest provocation—however, exercise also creates new neurons specifically designed to release the brain-calming neurotransmitter GABA. In essence, exercise helps the brain respond quickly to stress, but to calm down much more quickly after the stressful event, keeping unnecessary anxiety at bay. For benefits, researchers say quantity and intensity are important. Most recommend 45- to 60-minute sessions three to five days a week, aiming to reach 50 to 85 percent of maximum heart rate.
Mental Performance and Concentration: Exercise can also help improve mental function including memory, concentration and mental sharpness, according to research by Harvard Medical School. While regular, moderately intense workouts benefit the brain by maintaining healthy blood pressure, lifting mood and lowering stress, it also has a direct affect on brain chemicals. Exercise stimulates brain regions involved in memory to release a chemical called brain-derived neurotrophic factor (BDNF), according to Harvard Health Publications, the media division of Harvard Medical School. BDNF rewires memory circuits to work more effectively. “Not so long ago, neuroscientists assumed that humans were born with a certain number of brain cells—and that was it throughout one’s life,” writes Karen Postal, a neuropsychologist and clinical instructor at Harvard Medical School. “Now it’s clear that new cells are born throughout our lives, in the area of the brain responsible for laying down new memories, and this process is triggered by exercise. When we exercise—and it has to be enough to really sweat—neurogenesis, or the birth of new cells, is the result.” And, while exercise is how we generate new cells, we must put them to work in order for them to stick around. So consider taking a run, then following it up with a crossword puzzle, by practicing a new language or instrument, or by cooking an unfamiliar dish.
Sleep: Exercise’s relationship with sleep seems obvious: Fatigue our bodies during the day, sleep better at night. And for those without sleep disorders, this is often the case. However, when using exercise to treat insomnia in formerly sedentary individuals, results might take a while. A clinical psychologist and sleep researcher at Northwestern University, Kelly Glazer Baron was fond of prescribing exercise for her patients with insomnia. However, she often heard them complain that it didn’t help. Yet studies had shown exercise to be an effective treatment for the disorder. Digging into past studies, Baron discovered that, because those with sleep disorders tend to have “what we characterize as a hyper-arousal of the stress system,” as she told The New York Times, it takes longer for exercise to benefit their sleep. In fact, it can take as much as four months—long enough for exercise to help calm the underlying physiological arousal. Although results aren’t immediate (and exercising consistently can be more difficult without adequate sleep), after four months, the test subjects Baron examined were getting at least 45 minutes more sleep per night, which she says is as good or better than the most current treatment options, including pharmaceutical drugs.
Although any type of exercise is better than none, to reap the most health benefits from workouts— and maximize their potential to contribute to losing weight or maintaining a healthy weight—try these tips.
1. Go heavy. Lifting heavy weights is the best tactic for building muscle mass, which helps our bodies burn fuel more effectively, contributes to good balance and reduced falls, and more. Lift weights two to three times a week, giving muscles a rest between days. Find a weight-lifting program you like (you can find many from trainers online) and can do at home or at the gym; take a weight-lifting class; or set up an appointment with a personal trainer to customize an exercise plan for you. And don’t get complacent: Once the weight starts to feel less than challenging, step it up.
2. Go fast. Incorporating speed intervals into workouts is one of the most efficient ways to achieve results—even a few minutes of speed intervals can substantially improve health and cardiovascular fitness, according to reporting in The New York Times. In one study, researchers in Denmark found one type of exercise particularly beneficial—mostly because people stuck with it. Known as 10-20-30 training, this system can be used with any type of cardio exercise: for example, running, bike riding or rowing machine. Simply do the exercise gently for 30 seconds, at a moderate pace for 20 seconds and as hard as possible for 10 seconds (it need not be totally precise; you can count in your head). Do five such sets in a row with no pause, then rest for two minutes (stand still or walk slowly), then do five consecutive sets once more—the whole thing lasts just 12 minutes. Tack on your own warm up and cool down, five minutes each, for a quick, research-backed workout.
Mother Earth Living editor-in-chief JESSICA KELLNER is an exercise enthusiast who enjoys mixing it up with running, group fitness classes, yoga, weight training and more.