Ten years after gathering people’s baseline fitness habits—including workout length and intensity—researchers found that those who reported jogging or brisk walking 2 to 4 hours a week cut their risk of developing MS by 35 to 50 percent. (About 19 percent of inactive people developed MS, compared to just 12 percent of very active people.)
The cardiovascular impact of high-intensity training (HIT) exercise versus less intense exercise has been a longstanding debate, says cardiologist Eric Topol, M.D., director of the Scripps Translational Science Institute and a Men’s Health expert advisor. While the jury remains out, the new study lends credence to the high-intensity camp.
“Higher-intensity exercise does have a whole different impact on the body’s physiology,” says Dr. Topol. Everything is more pronounced: your heart rate is higher, your blood vessels are more dilated, and you’re revving up your cardiovascular system as you would a car, Dr. Topol adds.
The results of this study on the effects of different workout intensties and workout length on health are consistent with past studies on the topic: There’s some kind of a threshold that you need to surpass in order to see changes in your body and health. And it’s possible that shoort intense exercise triggers beneficial changes in glucose and lipid metabolism and blood pressure, lowering the risk factors that trigger metabolic syndrome and the associated diseases, according to David Maron, M.D., a cardiologist at Vanderbilt University’s medical center.
But don’t give up your leisurely evening walks just yet. There are still a number of studies indicating that low intensity exercise, when done consistently has several health benefits.
Many in-depth research studies have shown that regular daily exercise walking can cut your risk of death (from any and all diseases) in half! Walking at a moderate 3 mile per hour (mph) pace for at least three and a half hours every week (30 minutes a day) has been shown to dramatically reduce your risk of diabetes, heart disease, stroke, hip fractures, glaucoma, osteoporosis, cancer, depression and many other health problems.
The Honolulu Heart Study of 8000 men found that walking just two miles a day cut the risk of death almost in half. The walkers' risk of death was especially lower from cancer. Other studies have had similar findings - if you keep walking, you improve your chances of a longer and healthier life. A study by the Graduate School of Public Health, University of Pittsburgh, discovered that walking for 30 minutes a day cut diabetes risks for overweight as well as non-overweight men and women. A recent study in the Journal Circulation also supports this finding. The study found that just 2.5 hours of light exercise a week can reduce inflammation in your body thought to be a major contributing factor for developing heart disease. The key: Make sure your heart rate hovers around 120 beats per minute (think: not quite heavy breathing, but breathing more heavily than normal), and that you put in the recommended 2.5 hours for the week.
So maybe the happy medium is to combine both approaches for optimal health? While the BMJ Open study found that light physical activity didn’t decrease the participants’ metabolic syndrome risk—even if they walked for 2 hours a week—brisk walking was categorized as high intensity. If going hard for you means brisk walking, do that until it becomes easy, then take it up a notch. “Rigorous aerobic activity is really the best,” Topol says. So, if you enjoy your nightly stroll, just make sure you’re sweating it out in the morning, too.