The fitter you get, the more likely you are to feel that you can’t get enough oxygen during hard exercise

Contrary to what scientists once thought, even superficial cooling is enough to interfere with muscle oxygen supply.

Arbitrary goals are nonsensical. They also can be the source of great joy.

Singer-songwriter David Lindes found his way into running with help from the most unexpected teacher: a bull moose

Embarking on four days of total blackout, inside the sensory equivalent of a tomb, our writer went on a dark-cave retreat, the same one that quarterback Aaron Rodgers did

Look around the start line of an endurance race and you don’t see many tall competitors. Look on the podium, and you never see any. Why is that?

The benefits of training your mental skills are, by definition, all in your head. So how do we prove that it works?

The two pursuits have more in common than meets the eye

How do you make the best of a golf addiction? Add running.

Marijuana is still a banned substance for athletes, but new research is chipping away at the idea that it makes you faster

The logic is good and the anecdotes are common, but the evidence is shakier than expected, researchers find

Colin Gay, a 48-year-old father of two from Virginia, is doing something that few of us could ever imagine

New research suggests exercise may boost the “love hormone,” the latest in a long line of brain-boosting molecules

What’s an acceptable baseline of fitness? According to the most adventurous American president in U.S. history, it was an ultra endurance trek.

Our strength-running coach recommends occasionally going off script to reach your running goals

The pursuit of performance in a bottle inherently undermines our attempts to get faster, stronger, and healthier, our Sweat Science columnist argues

AI is improving with hyperspeed sophistication. Can it prepare you for the most beloved marathon in the world?

Is Taylor Swift an elite endurance athlete? On the Eras tour, the singer-songwriter is performing three nights a week, singing and dancing for as long as it takes most people to run a marathon.

InsideTracker’s massive database of more than 23,000 runners shows that more mileage is associated with better biomarkers

After a certain number of hours, endurance races are basically eating competitions

Adults will take recreational cues from their children, “unprocessed” will become a marketing asset, and rodents will show us the way to eternal life. 

It turns out you can absorb more carbohydrates than sports nutritionists thought. But does it actually make you faster?

The 26th president once demanded that military personnel be able to walk 50 miles in 20 hours. I set off on an ill-fated mission to see if I could do it myself.

In the form of a handy little email, or a push notification, anything to remind me that I’m not heading too quickly toward the afterlife just yet

We try to gain a competitive edge from things like nutrition, recovery, weight training, and new shoes. But what if becoming a parent does the trick?

You felt fine a day after your long run—so why the heck are you slogging through your easy workout two days later?

A selection of (mostly) new titles for fans of science, endurance, fitness, and adventure

Over the past century, “maximal oxygen uptake” has turned out to be a valuable marker of both endurance and health.

You won’t freeze your lungs exercising outdoors this winter, but there are reasons to be cautious about inhaling extremely cold air

This summer Courtney Dauwalter made history, becoming the first athlete to win the three biggest races in ultrarunning in the same year: the Hardrock 100, the Ultra-Trail du Mont Blanc, and the Western States Endurance Run. What’s her secret?

Want to ride like Pete Stetina? Learn how he and other top athletes use Wahoo’s latest tools and technology to achieve their goals—and how you can too.

Tap your full potential with advice from professional coaches and athletes—and the inspiring stories of runners who refuse to be limited

Both require self-motivation, incremental and attainable goals, and a whole lot of follow-through

To ward off cognitive decline, a new analysis suggests that strength matters more than how much muscle you have

People all over the place are creating outrageous unofficial athletic contests that are equal parts grueling and just plain silly. What’s going on?

When you’re plodding so slowly it feels like you're moving backwards, wouldn’t it be better to just... walk?

The new science of skill acquisition can help coaches and athletes get more out of their workouts

News flash: All that data you’re mining may not be good for your health

Scientists want to know why we don’t keep getting bigger and stronger forever

A rural road relay offers the author a chance to return home and consider important questions, like: Who has the aux in the support van and where did they find this weird club track?

A new federal law, the Rodchenkov Act, has the potential to dramatically clean up international sports. A case involving a Texas doping ring illustrates how the new legislation works.

Toss out the marathon prediction equations. Understanding what determines ultra performance takes a whole different approach.

All the digital training data in the world may not tell you whether your workout was any good

A rigorous new study finds small changes in heart rate and subjective feelings of recovery. Do they matter?

A new study of athletic career trajectories finds that early success is less meaningful than you’d think

How failing in training and racing can make you a stronger runner

‘The Runcast’ is a podcast hosted by KEXP’s John Richards that focuses on mental wellbeing through running and music. It’s never been more popular.

Coach Cory Leslie fosters a new team of distance runners at the Under Armour headquarters

Under Armour Coach Lara Rogers shows how women can excel in the pro ranks

Three variations of the glute bridge to strengthen and and add power to your stride

Researchers assess the potential benefits—and downsides—of the hundreds of bioactive compounds in your morning brew

Running fast is important, even for beginners and endurance athletes. Here’s why, plus four essential workouts to start.

Find out how you can achieve your fitness goals and raise money for blood cancer patients and families at the same time

Tramadol has a long history of suspected abuse among cyclists, and now there’s enough data to put it on WADA’s banned list

Sports scientists weigh in on the trends that will keep the PRs coming

Analyzing glucose data from endurance athletes offers new(ish) insights, with the potential of more to come

You can boost performance by tackling heavy blocks of training—if you avoid excess fatigue. Here’s how to walk the line.

Feeling out of shape? Maybe you should run up and down a mountain three times.

To optimize your health or supercharge your training, you sometimes need to look beyond the lab

This avid runner wore his GPS watch 24 hours a day for one month, performing every single workout it suggested

Cutting-edge benefits from being race-fit at 83

After seeing more and more people join in on this outdoor fitness craze, I decided to try it for 30 days

A high-tech approach called metabolomics offers a new perspective on how your body bounces back from 26.2 miles

Running volume is important, but how you structure your training might matter more

Four unconventional ways to manage chafing—and effective alternatives

She knew she was going to be the best triathlete in the world one day. But first she had to learn to swim.

These five red flags might be keeping you from running faster

The latest research suggests that muscle oxygen can detect exercise thresholds, with no blood required

Researchers present new findings on mental fatigue, mental training, and the importance of your surroundings

This one trick can get you out the door and into a routine of consistency and health, whatever life brings

How much mileage should you be running? Two top coaches share helpful ways to think about the volume question so that you can find your optimal mileage number.

At the end of my mother’s struggle with Alzheimer’s disease, I realized I needed to handle my sorrow the same way I approached athletic training

Scientists reconsider the assumption that it only helps strength and power athletes

After being hit by a car, the entrepreneur was afraid to cross the street. Training for a marathon helped her take back her life.

Plyometrics can make you a more efficient runner, and it turns out they don’t need to be complicated or risky

Running can give you a longer life, better sleep, improved immunity, mood, and more—it’s even good for your knees and lower back

To build endurance as a runner is to build “capacity.” But what does this look like? Strength running coach Jason Fitzgerald explains. 

In an excerpt from her forthcoming book, ‘Up to Speed: The Groundbreaking Science of Women Athletes,’ longtime Outside contributor Christine Yu argues that female athletes deserve their own benchmarks for athletic success.

Researchers look back on the lessons from 25 years of “live high, train low”

Maybe you should start writing a little something about your run, too