Gretchen Reynolds

In a study done with mice, horses and people, researchers found clues as to which types of exercise suppress appetite and why.

By Gretchen Reynolds

A new study found exercisers expel a shocking number of tiny aerosol particles when they are working hard.

By Gretchen Reynolds

Science says you may need less exercise than you think to live a long and healthy life.

By Gretchen Reynolds

In her new book, Jennifer Heisz blends personal experience and the latest science about how exercise can improve your mental well-being.

By Gretchen Reynolds

It’s the one exercise most of us should be doing. But we need to do it right.

By Gretchen Reynolds and Brown Bird Design

Men and women who briefly contracted their arm muscles as hard as possible once daily increased their biceps strength by up to 12 percent in a month.

By Gretchen Reynolds

People who worked out in even moderately polluted air did not show the kinds of brain improvements tied to a lower risk of dementia.

By Gretchen Reynolds

This was featured in live coverage.

By Gretchen Reynolds

A 90-minute walk, jog or bike ride after getting vaccinated may boost your body’s immune response.

By Gretchen Reynolds

The need for healthy, active grandparents who can help with child-rearing may be encoded in our genes.

By Gretchen Reynolds

Ten minutes of moderate exercise daily would prevent more than 111,000 premature deaths a year, a new analysis found.

By Gretchen Reynolds

Working out at different times of the day might have unique benefits for health, an ambitious new study in mice suggests.

By Gretchen Reynolds

Cross-country ski racers were less likely to develop anxiety disorders. The good news is less intense aerobic activities may provide similar benefits.

By Gretchen Reynolds

Muscles develop a lasting molecular “memory” of past resistance exercises that helps them bounce back from long periods of inactivity.

By Gretchen Reynolds

The most vital exercise science of 2021 provided a reminder that our bodies and minds can flourish, no matter our circumstances.

By Gretchen Reynolds

People who are aerobically fit and work out a lot tend to imbibe more than their less fit peers.

By Gretchen Reynolds

A new analysis of data from “The Biggest Loser” highlights the complex ways the body compensates when we drop pounds.

By Gretchen Reynolds

Among 52 incentives to exercise, giving people a 9-cent award if they returned to the gym after missing a workout helped the most.

By Gretchen Reynolds

Simple activities like walking boost immune cells in the brain that may help to keep memory sharp and even ward off Alzheimer’s disease.

By Gretchen Reynolds

For most of us, exercise impacts our hunger and weight in unexpected and sometimes contradictory ways.

By Gretchen Reynolds

More than 46,000 cancers in America each year, or about 3 percent of cases, could be prevented by meeting physical activity guidelines.

By Gretchen Reynolds

What you need to know about high-intensity interval training, or HIIT.

By Gretchen Reynolds

Working out may seem like the last thing someone in pain wants to do. But it can bring relief.

By Gretchen Reynolds

Twenty minutes of cycling may prime muscles in the arms to grow more while lifting.

By Gretchen Reynolds

A study in mice raises intriguing questions about the ways that hormones influence the brain and motivate the body to move.

By Gretchen Reynolds

Focusing on external sights and sounds, rather than what’s going on in your body, made running feel easier and improved performance.

By Gretchen Reynolds

Women undergoing chemotherapy for breast cancer who stayed physically active had fewer problems with memory and thinking.

By Gretchen Reynolds

People typically lower their risks of heart disease and premature death far more by gaining fitness than by dropping weight.

By Gretchen Reynolds

Our bodies compensate for at least a quarter of the calories we expend during exercise, undermining our best efforts to lose weight by working out.

By Gretchen Reynolds

Two studies suggest the sweet spot for longevity lies around 7,000 to 8,000 daily steps or about 30 to 45 minutes of exercise most days.

By Gretchen Reynolds

Climbing stairs, doing jumping jacks or even taking as few as 15 steps during mini-breaks improved blood sugar control among office workers.

By Gretchen Reynolds

Irisin, a hormone produced by muscles during exercise, can enter the brain and improve cognition, a mouse study suggests.

By Gretchen Reynolds

Scientists are developing devices and clothing that make running and walking easier and more enjoyable.

By Gretchen Reynolds

High-intensity interval training has surprising benefits for fitness and physical power, but don’t stay seated the rest of the day.

By Gretchen Reynolds

The best world-class athletes often dabble in a range of sports when young before rising to the top of their game in one, a new analysis found.

By Gretchen Reynolds

Falling during skateboarding or other activities does not have to end in serious injury. Olympic athletes, coaches and scientists tell us how.

By Gretchen Reynolds

A cellular chat after your workout may explain in part why weight training burns fat.

By Gretchen Reynolds

Older men and women who walked for six months showed improvements in white matter and memory, while those who danced or did stretching exercises did not.

By Gretchen Reynolds

People who regularly do muscle-strengthening exercises are about 20 to 30 percent less likely to become obese over time than people who do not.

By Gretchen Reynolds

The advice that we take 10,000 steps a day is more a marketing accident than based on science. Taking far fewer may have notable benefits.

By Gretchen Reynolds

Runners who made eight or more changes to their running routines were at high risk of injury, especially if they were feeling stressed.

By Gretchen Reynolds

As record high temperatures batter much of the country, expert advice on staying active this summer.

By Gretchen Reynolds

People who start to exercise before or during middle age typically save from $824 to $1,874 annually on health care costs after retirement.

By Gretchen Reynolds

Researchers are studying the proteins in blood to learn why some of us respond to certain forms of exercise better than others.

By Gretchen Reynolds

Men who had physically strenuous jobs lived, on average, about a year longer than those who were deskbound.

By Gretchen Reynolds

Almost half of the athletes this year will be women, more than in any Games in history. And in some events, women and men will compete together.

By Gretchen Reynolds

Late-day exercise had unique benefits for cholesterol levels and blood sugar control, a study of overweight men eating a high-fat diet found.

By Gretchen Reynolds

Pedal-assisted electric bikes provided a faster and more “fun” commute while raising breathing and heart rates enough to contribute to fitness.

By Gretchen Reynolds

Physical activity can promote a sense of purpose in life, creating a virtuous cycle that keeps you moving.

By Gretchen Reynolds

Even a gentle session of leg lifts set off an exaggerated nervous system reaction in older women with rheumatoid arthritis.

By Gretchen Reynolds

Physical activity during pregnancy might have long-lasting benefits for a child’s health, new research suggests.

By Gretchen Reynolds

Icing muscles after strenuous exercise is not just ineffective, it could be counterproductive, a new study in mice suggests.

By Gretchen Reynolds

People who tended to be sedentary were far more likely to be hospitalized, and to die, from Covid than those who exercised regularly.

By Gretchen Reynolds

Scientists have found that grizzlies, like people, seem to choose the path of least resistance.

By Gretchen Reynolds

Older people with mild cognitive impairment showed improvements in brain blood flow and memory after a yearlong aerobic exercise program.

By Gretchen Reynolds

A new study hints that excessive HIIT may harm your mitochondria, the energy generators found in every cell of your body.

By Gretchen Reynolds

Indoor fitness classes, which often result in heavy breathing in poorly ventilated rooms, can be risky. Here’s a guide to help you decide if your gym is doing enough to prevent the spread of Covid-19.

By Tara Parker-Pope and Gretchen Reynolds

Dogs orient and move in synchrony with family members, which may have implications for the emotional development of people and pets.

By Gretchen Reynolds

For years we’ve been crediting endorphins, but it’s really about the endocannabinoids.

By Gretchen Reynolds

Sedentary, older adults who took aerobic dance classes twice a week showed improvements in brain areas critical for memory and thinking.

By Gretchen Reynolds

What we eat may be more important than how much we move when it comes to fighting obesity.

By Gretchen Reynolds

The more you do, the better, but even mild exercise like walking produces benefits for cardiovascular health, a large new study found.

By Gretchen Reynolds

We can thank our heads and shoulders — and not just our knees and toes — that we evolved to run as well as we do.

By Gretchen Reynolds

To spur innovation and ideas, try taking a walk.

By Gretchen Reynolds

Men at risk for diabetes had greater blood sugar control and lost more belly fat when they exercised in the afternoon than in the morning.

By Gretchen Reynolds

High-intensity workouts get a lot of attention and can be great for health. But moderate physical activity may have metabolic advantages.

By Gretchen Reynolds

Five minutes of burpees, jump squats and other calisthenics, alternating with rest, improved aerobic endurance in out-of-shape men and women.

By Gretchen Reynolds

Inactive people started moving more if they received daily step targets that exceeded their usual number by about 500 steps.

By Gretchen Reynolds

Four seconds of intense intervals, repeated until they amount to a minute of total exertion, led to rapid improvements in strength and fitness in middle-aged and older adults.

By Gretchen Reynolds

Including high-intensity training in your workouts provided better protection against premature death than moderate workouts alone.

By Gretchen Reynolds