Exercise & Fitness Archive

In the journals

How many push-ups can you do in a minute? The number may predict your risk of heart disease, suggests a study published online Feb. 15, 2019, by JAMA Network Open.

Harvard researchers analyzed data from 1,104 healthy firefighters, average age 40, who did not have cardiovascular disease. Each man performed as many push-ups as possible in one minute. The men also had treadmill tests to measure their cardiovascular health and aerobic fitness. After 10 years, the researchers found that the men who had originally performed the most push-ups were least likely to get heart disease.

Ask the doctors

Q. I recently read that I don't need to exercise all at once during the day to get health benefits. Is this true?

A. It's true — at least according to the newest version of the Physical Activity Guidelines for Americans published by the U.S. Department of Health and Human Services (HHS).

Running for 15 minutes a day or walking for an hour reduces the risk of major depression, according to a recent study.

It may be possible to outrun depression, according to a study published online January 23 by JAMA Psychiatry.

"We saw a 26% decrease in odds for becoming depressed for each major increase in objectively measured physical activity," says study author Karmel Choi, a clinical and research fellow at the Harvard T.H. Chan School of Public Health. "This increase in physical activity is what you might see on your activity tracker if you replaced 15 minutes of sitting with 15 minutes of running, or one hour of sitting with one hour of moderate activity like brisk walking."

Research we're watching

You've probably heard that it's harmful to your health to spend too much time sitting around. But a study published January 14 in the American Journal of Epidemiology shows that it may be possible to reverse some of that harm by engaging in short periods of movement throughout the day.

Researchers recruited 8,000 people ages 45 and older and asked them to wear an activity monitor for a week. The device tracked them throughout the day to see how much they sat and how much they moved.

Exercise and stretch daily to keep ankles flexible.

Ankle stiffness can do a number on your mobility. It can make it difficult to remain active or even get out of bed in the morning and walk across the room. "Motion restriction usually occurs more in the upward than downward direction, so it becomes harder to walk uphill, wear flat shoes, or keep feet pointed straight ahead," says Dr. Christopher DiGiovanni, chief of foot and ankle surgery at Harvard-affiliated Massachusetts General Hospital.

A tricky joint

The ankle is a vulnerable structure. It's made of the ends of the lower leg bones (the tibia and fibula), which hold the talus bone of the foot in between them. The joint is stabilized by ligaments and powered by muscles that work in concert to enable ankle and foot motion and accommodate uneven surfaces when you stand or walk.

News briefs

We often tell you about using aerobic exercise and a healthy diet to try to stave off dementia. But will those approaches help if you already have the slight but noticeable change in memory and thinking known as mild cognitive impairment (MCI)? A small randomized trial (the gold standard type of study) published online Dec. 19, 2018, by Neurology suggests the combination of diet and exercise may indeed help. Researchers studied 160 sedentary older adults who had MCI as well as one or more cardiovascular disease risk factors, such as high cholesterol. Participants were randomly assigned to do aerobic exercise, to follow a heart-healthy diet (the Dietary Approaches to Stop Hypertension, or DASH, diet), to do a combination of aerobic exercise and the DASH diet, or to just get weekly heart health education. After six months, people who just exercised several times a week got a little bump in executive function (thinking skills that help us plan and organize), but the biggest change was seen in people who both followed the DASH diet and did aerobic training three times a week. Their improved planning skills were equivalent to reversing nearly 10 years of brain aging, compared with study participants who didn't exercise or improve their diets. The findings demonstrate that it's never too late to start exercising and eating right.

Image: © adamkaz/Getty Images

News briefs

Many people think the only reason for regular exercise is that it helps you maintain a healthy weight. Not true. A sedentary lifestyle can cancel the potential heart benefits of weight control, according to a study published online Dec. 4, 2018, by the American Journal of Cardiology. Researchers looked at five years' worth of health survey responses and weight calculations from thousands of overweight and normal-weight people ages 40 to 79 who'd never had heart disease. Scientists noted the participants' amount of abdominal fat, waist size, and self-reported amounts of physical activity, then calculated everyone's cardiovascular disease risk. The results: 30% of sedentary people with a normal weight had about the same risk for a heart attack or stroke as people who were overweight. Sedentary adults whose weight was normal also had higher levels of belly fat, shortness of breath upon exertion, and an unhealthy waist circumference compared with normal-weight adults who exercised regularly. However, people with a normal weight who exercised at least 150 minutes per week were 58% less likely to have a heart attack than those in the study who were overweight.

 Image: Halfpoint/iStock

In addition to boosting fitness and easing stress, yoga may also help you embrace a healthier lifestyle.

Many people think of yoga mainly as an activity that promotes flexibility and balance. But this ancient tradition also includes breathing exercises, relaxation, and meditation. Together, these practices can lead to measurable improvements in factors connected with cardiovascular health, such as lower blood pressure, better sleep, and less artery-damaging inflammation.

"There are four distinct but interconnected areas in which yoga has specific benefits, not just for heart disease but any disease," says yoga researcher and neuroscientist Dr. Sat Bir Singh Khalsa, assistant professor of medicine at Harvard Medical School. Following are summaries of the four areas.

Research we're watching

The more steps you take per day, the more flexible your arteries may be, a new study suggests. Elastic, flexible arteries are a sign of a healthy cardiovascular system, while stiff, inflexible arteries are a harbinger of heart disease.

Researchers pooled findings from 10 studies that measured people's daily step counts and their arterial stiffness, using a technique called pulse wave velocity. With every heartbeat, a wave of blood travels through the body's network of arteries. Measuring the speed of the pulse wave provides information about how stiff or how flexible the arteries are. The stiffer the arteries, the faster this wave travels.