Compared to the pumping intensity of spin or Zumba, a tai chi class looks like it’s being performed in slow motion. But this exercise program is far more dynamic than it looks. As an aerobic workout, tai chi is roughly the equivalent of a brisk walk. And as a resistance training routine, some studies have found it similar to more vigorous forms of weight training. It is especially useful for improving balance and preventing falls—a major concern for older adults. Tai chi helps improve balance because it targets all the physical components needed to stay upright—leg strength, flexibility, range of motion, and reflexes—all of which tend to decline with age. It also offers an emotional boost to balance by removing the fear of falling that can make some people afraid to exercise.
Exercise and Fitness
We tend to think of type 2 diabetes as a disease that afflicts people who are overweight. But it can also appear in people with perfectly healthy weights—and be more deadly in them. A study published in the Journal of the American Medical Association indicates that normal-weight people diagnosed with type 2 diabetes have double the risk of dying from heart disease and other causes than overweight people with diabetes. Such apparent “protection” by excess weight has been called the obesity paradox. It’s been seen with other conditions, like heart failure and end-stage kidney disease. That doesn’t mean gaining weight is a healthy strategy. Instead, it probably means that something else besides weight—like the amount of fat around the waist—may be contributing to the onset and severity of type 2 diabetes. These new findings underscore the importance of strength training for everyone, no matter what their weight.
Nicely timed for the 2012 Olympic Games in London, the British Medical Journal (BMJ) has published several articles revealing the “truth about sports drinks.” That truth is this: drink when you are thirsty and don’t waste your money or calories on sports drinks—choose water instead. Before the rise of sports drinks, athletes (and the rest of us) drank water when we exercised or got sweaty. How did we know when to drink, or how much? The way humans have known for eons—thirst. But as the BMJ team describes, sports drink makers spent a lot of money sponsoring less-than-rigorous research damning thirst as a guide to hydration and casting doubt on water as the beverage for staying hydrated. The bottom line is that thirst remains an excellent gauge of hydration, and plain old water is still the best way to replace lost fluid.
Thanks to medical advances in detecting and treating stroke, the risk of dying from one is now lower than it used to be. Unfortunately, many stroke survivors are left with a disability. In fact, stroke is the leading cause of serious long-term disability in the United States. A new study from Indianapolis suggests that yoga may benefit some stroke survivors. In this study, 47 stroke survivors were divided into three groups. Some took part in a twice weekly group yoga session for eight weeks, and others received standard follow-up but no yoga. There were several benefits in the yoga group, including improved balance, improved quality of life, reduced fear of falling, and better independence with daily activities. Although small, this study adds to findings from other research that yoga may help stroke survivors in several ways.
Is there a spring in your step—or a wobble in your walk? The speed and stability of your stride could offer important clues about the state of your brain’s health. According to new research, an unsteady gait is one early warning sign that you might be headed for memory problems down the road. A group of studies reported last week at the Alzheimer’s Association International Conference in Vancouver, Canada, revealed a strong link between walking ability and mental function. What’s behind this connection? Walking is a complex task that requires more than just moving the leg muscles. Walking requires scanning the environment for obstacles and safely navigating around them, all while talking and carrying out various other tasks. The studies found that walking rhythm was related to information processing speed; walking variations and speed were associated with executive function (the mental processes we use to plan and organize); and walking speed became significantly slower as mental decline grew more severe.
If you start an exercise program, it only seems fair that you should see your hard work reflected in lower numbers on the scale. If it isn’t, don’t despair—or quit exercising. You are still helping your heart, lungs, and every other part of your body. A study in the Journal of the American College of Cardiology looked at the effects of exercise and/or weight loss on cardiovascular health among more than 3,000 men and women who were initially overweight. As I write in the July issue of the Harvard Health Letter, those who exercised consistently and lost weight had the biggest reduction in heart attack risk over six years of follow-up. Exercising without losing weight and losing weight without exercising offered smaller benefits. Although exercise and weight don’t always move in the same direction, they are both important for health.
Daily exercise appears to reduce a woman’s risk of developing breast cancer, according to a study published online in the journal Cancer. The type or intensity of the exercise didn’t seem to matter, as long as it was done often. How much exercise is needed to lower breast cancer risk? In this study of 3,000 women, 10 to 19 hours a week (about two hours a day) had the greatest benefit. Age didn’t seem to matter—physical activity reduced breast cancer risk in younger women during their reproductive years and older women after menopause. What did make a difference in the effect of exercise was weight gain—especially after menopause. Gaining a significant amount of weight essentially wiped out the benefits of exercise on breast cancer risk in older women.
A new book from First Lady Michelle Obama, “American Grown: The Story of the White House Kitchen Garden and Gardens Across America,” details the challenges and joys the First Lady has experienced with her now-famous White House garden. It also looks at community gardens all across America, and how they can improve health. The book contains helpful hints for starting your own vegetable garden, as well as a school or community garden. This effort dovetails with Mrs. Obama’s “Let’s Move” initiative. In addition to getting more physical activity, so the thinking goes, eating more food harvested from the ground and less from packages can help kids — and adults — become healthy or stay that way. The health benefits of growing your own food range from helping you eat more fresh fruits and vegetables to deciding what kinds of fertilizers and pesticides come in contact with your food.
Exercise makes cells burn extra energy—that’s one way it helps control weight. It also generates a newly discovered hormone, called irisin, that transforms energy-storing white fat cells into energy-burning brown fat cells. Irisin also appears to help prevent or overcome cellular changes that lead to type 2 diabetes. The hormone does this by helping transform energy-storing white fat cells into energy-burning brown fat cells. White adipose tissue, more commonly known as body fat, is the tissue that dimples thighs, enlarges waists and derrieres, and pads internal organs. Each white fat cell stores a large droplet of fat. Brown fat, in comparison, is chock full of energy-burning mitochondria. Its main function is to generate body heat by burning fat. A team led by Dr. Bruce Spiegelman, professor of cell biology and medicine at Harvard Medical School, has identified irisin in mice and humans and showed how irisin transforms white fat cells into brown ones, at least in mice.
Surviving cancer was once a challenging achievement. Today, more than 12 million Americans are cancer survivors, and many live long after their diagnoses. New guidelines from the American Cancer Society (ACS) offer them science-based advice for eating better and staying active—two keys to healthy living for cancer survivors and everyone else. The report, called Nutrition and Physical Activity Guidelines for Cancer Survivors, is available for free from the ACS website. The guidelines provide specific advice for survivors of a variety of major cancers: prostate, colorectal, lung, breast, ovarian, endometrial, upper GI, head and neck, and hematologic. They urge cancer survivors to maintain a healthy weight, avoid inactivity and return to normal daily activities as soon as possible following diagnosis, eventually aim to exercise at least 150 minutes per week, and follow an eating pattern that is rich in vegetables, fruits, and whole grains.