Scientists have already created a device that reduces the energy cost of running and predict mainstream applications within four years.

It depends—but you can hold your breath longer in cold water

She won Olympic gold in a sport that chose her. Can she do the same in the one she truly loves?

The perfect summer day in this California beach town

Forget about counting reps in your head. This clever jump rope uses embedded LEDs to project that number in front of you.

American churches are building first-class gyms to get followers in shape and attract new members to the flock. Critics see lucrative businesses masked as ministries, but the programs are a spirited defense against our obesity epidemic.

How endurance athlete Patrick Sweeney puts away nearly 3,000 calories a day on the ketone diet

Two weeks of full-time, one-on-one instruction at Exos can set you back $4,800. Here’s how to get many of the same performance benefits without taking out a second mortgage.

Goodbye crazy binges, hello almond butter?

An expert look at the most feasible—and nuttiest—submissions

Inside Specialized and Stanford University’s new alliance to research cycling’s effects on kids with ADHD

The suit, filed after 28-year-old Avishek Sengupta drowned at the 2013 Tough Mudder Mid-Atlantic event, had major implications for the obstacle-course-racing industry

The secret to unlocking your athletic potential is in your genes, but scientists don’t know what they’re telling us—yet

And why they’re more susceptible to diet trends

And when they'll be smashed—because half the fun of records is watching them fall

Inside the revolution to reclaim city waterways for recreation

Sorry, that wildly popular New York Times story is not for you

A lawsuit reveals the personal spat that brought an end to the iconic endurance event

A new detergent called DeFUNKit promises to scrub stinky bacteria from synthetic workout apparel. We put the stuff to the test during a week of skiing, running, and traveling—and found we smelled as good on day seven as we did on day one.

Why Aussie athletes often turn to supplements when living high

The somewhat simple answer to a popular question

Champ Amby Burfoot and streak runner Ben Beach give the DL on the world’s most storied marathon

Everything you need to know about ultrarunning's ultimate gateway drug

What you need to know to start competing in the ultimate chill winter sport

Insider tips on conquering Aspen’s hottest event

Essential race-day, gear, and training intel

Faves tweaked to optimize performance and recovery

4 strategies to help you quit worrying and learn to love the snow

The right moves make you faster and more resilient. Here's how to get the most important part of your training routine right.

Outsmart three winter-specific risks before, during, and after your workout

The new genetic tool has the potential to increase resistance to muscular injury or stress fractures—even produce stronger, faster athletes—but it's a puzzle that could take decades to solve

The sport ends its most outrageous elements in a quest for longevity

A new study brings up two more glaring reasons to avoid hitting the wall in training

Inside the first ever Faith and Fitness Conference in New Orleans

Turns out the navigation devices routinely overestimate distance traveled. Why that quirk hasn't—and won't—affect cyclists.

An effort by any other name won’t make you as great

And how to put off being totally, utterly f*ed

The spirit of long-distance triathlons is being swallowed by behemoths like the World Triathlon Corporation. And it's our own fault.

Researchers say there is indeed too much of a good thing, and it’s killing your athletic potential

New research shows that while high-intensity movement is beneficial, nothing compares to the benefits of more movement

Oxygen seeks to show the beauty of female athleticism—and that women can be kick-ass athletes for life

Athletes competing for no country are not new to the Games, but a concentrated effort to recruit more of them could bring exciting new competition next year

Do you really need the calories or just want them out of habit?

DNA testing service 23andMe is now FDA approved

You've probably been taught to run on soft surfaces whenever possible. Truth is, it doesn't make a difference.

In search of the everyman who will make bike commuting the norm

Cameras that shoot 360-degree footage could make virtual fitness classes a reality. But the tech’s not quite there yet.

Ultra coaches Eric Orton and Jason Koop on the importance of strength and speed over mileage

We like the price, but can this bra stand up to more expensive options from established sports brands? We put three models to the test to find out.

The so-called superfood is attempting a comeback, but don’t be fooled by its siren call

What the purchase by a Chinese billionaire means for the sport

We test three of the latest performance fuels in search of the ultimate podium snack

From extreme athlete Niccolo Porcella, the man who survived The Biggest Wipeout Ever

No, athletes aren't OD'ing on salt pills. But here's when you should lay off of them.

Columbia Sportswear announces it will pay two people a full six-month salary, plus benefits, to test gear around the world

A semi-scientific guide to sussing out the cheats

Have a blast while keeping your bike tire side down

A primer from overall winner of the Canadian Death Race, Alissa St. Laurent

Brought to you on film by running’s greatest bromantical couple

The trick is educating them with these honest, science-supported reasons why pets make our lives better

Once AT speed record attempt is complete

Exercises guaranteed to up your game, no matter your sport

Forget complicated workout regimens. CrossFit phenom Christmas Abbott shows simple strength exercises are all you need to start feeling fierce