How you can reboot your circuit training routine by ditching the rest interval.

Pro surfing’s go-to trainer Paul Hiniker lays down 10 steps to get your body ready for anything this summer

Marco Sanchez demonstrates.

Marco Sanchez demonstrates.

Marco Sanchez demonstrates.

Marco Sanchez demonstrates.

I run a lot and feel like I’ve had back pain forever. I read about a new study that found bacterial infections cause 40 percent of chronic back pain. Does that study apply to athletes with back pain? Should I ask my doctor about getting tested for a bacterial infection?

The ultimate guide to finding your ideal race

Increase your hip flexibility and take your upper body and core strength to the next level

Whenever I have a tough task to complete at work, I feel like my after-work workout suffers. Can thinking hard hurt my physical performance? Does my brain use up more energy the harder I have to think?

Now that I’m 40, I feel like I don’t recover as quickly from workouts as I did when I was younger. Is there a scientific explanation for this? Or is it all in my head?

First, ditch the salt tablets. “The biggest misconception is that exercise-associated muscle cramping is due to dehydration or electrolyte imbalances,” says Martin Schwellnus, a professor of exercise science at the University of Cape Town, in South Africa, and one of the world’s leading researchers on the subject.

Is it possible to be strong without having big muscles, or to be huge but not very strong?

Move over EPO: Dynavision’s CoreControl cooling glove enhances performance with just a vacuum and ice

The extreme polar explorer on rock lifting, noodles, and scheduling conflicts

Would taking a shot from an EpiPen during my race give me an advantage?

I read that NFL players over hydrate before their games. Should I be doing the same thing before my marathon?

Should I take ibuprofen before or after hard training to limit pain?

I want to go water skiing on spring break. Got any tips on how to prepare so I can stay up for longer than a minute and don’t hurt myself?

I just finished my first marathon, and I’m ready for a rest. How long before I start losing the benefits of my peak fitness level?

What kind of damage do bumps do to your body? What can I do to strengthen beforehand and counteract the aftereffects?

Or will I be totally out of shape this spring?

The prosecutor in the Oscar Pistorius bail hearing claimed that the athlete was found with a box of steroids. How likely is it that PEDs could contribute to a murderous rampage?

The upstart climbing phenomenon reveals the secrets to his success

My buddies and I are training for a race together, and the other day we got on the topic of pre-sporting event sex. Some of the guys swear it can have a negative impact on race-day performance; I say it helps calm my nerves. Who’s right?

It’s not just the pros who can benefit from a few sessions with a sports psychologist. Here’s how you can, too.

My gym has one of those vibration machines that’s supposed to help you lose weight by standing on it. Do these things really work—and are they safe?

Decades of research into the compounds that make up snake venom has led to some startling discoveries

As climbing moves toward its shot at the Olympics, the stakes are rising for the next generation of athletes. Will the temptation to get an edge be too much for some of them to handle?

David Roth went to the Monster Energy Invitational, and he found a sport still trying to figure out how to make its place on the American sports landscape

When he competes in triathlons, nine-year-old Conner Green puts in extra work so that his seven-year-old brother Cayden Long can race with him. Cayden has cerebral palsy and can't walk on his own. In the swim portion, Connor pulls Cayden in a raft. In the running portion, he…

I’ve heard a lot about how exercise can help me live longer, but does it matter what type of exercise I do?

Do athletes have a higher pain tolerance?

If I want to drop pounds in the new year, should I focus more on cardio conditioning or strength training?

Outside, inside, gravity, space, time, whatever: this thing transcended every boundary

Probably not

I’ve read a lot of claims recently that exercise makes you smarter. But how, exactly, does it work?

I’ve been having trouble with Achilles tendinosis, so a friend mentioned that I should look into prolotherapy. What’s the difference between that and PRP, and is it worth it?

Weekend gladiators are lining up in droves to risk hypothermia and electroshock in obstacle races by the millions and contributing to one of the fastest growing industries in our world

Pain is the name of the game at Tough Mudder, Spartan Race, and other big obstacle-course races

Is it therapy for a society deeply affected by the wars of our time, a renegade sport for rebels who can't stand rules and restrictions, or something else entirely?

I’m usually not hungry right after I work out. Does exercise suppress appetite? If so, how does that affect weight loss?

Everything you need to improve your time on the course

I have trouble figuring out how I should be training during the holidays, when the weather’s dreary, the food’s plentiful, and I don’t have any races planned. But I don’t want to pull a Jan Ullrich. What should I do?

Chrissie Wellington. Photo: Triitalian/Flickr Triathlete Chrissie Wellington announced on her blog yesterday that she is retiring from Ironman triathlons. Wellington won the Ironman World Championship in 2007, 2008, 2009, and 2011. The 35-year-old…

I hike every Wednesday morning at 6:30 a.m. with two friends. They're very fast and charge right up the hill, whereas I'm much slower at that time of the morning. But in the afternoon, I'm much faster. Is there any physiological or scientific reason why one person is faster in the morning and another is faster in the afternoon? And is there any truth to "morning" people and "nighttime" people in terms of athletic performance?

Just about every time I work out, my face turns beet red. Sometimes it lasts long after I’ve stopped exercising, which makes running during my lunch break difficult. Why does this happen? And is there anything I can do about it?

Len Stanmore, 60, is currently in Antarctica, competing in one of the world's most grueling footraces. If he completes it, he'll not only be a one-time overweight retiree who got sick of the golf course, but also the first person to climb the Seven Summits, ski to both poles, and complete the 4 Deserts Grand Slam.

How does implanted saline and silicone behave under extreme conditions, whether at jet-cruising altitude or during a deep-sea dive?

I always get the post-workout chills, even when it’s warm outside. What causes them, and is there anything I can do to avoid it in future?

I heard alternating hot and cold water is just as effective as an ice bath at speeding up recovery, but way less painful. Is this true? How do I do it?

An Olympic sport at the turn of the 20th century tries to find its way back into the modern Games

Is it true that sleeping well two nights before an event is more important than sleeping well the night before?

I’ve been reading about how sitting at work all day can cause heart attacks and early death. But if I’m training 15 hours a week, should I still get a standing desk, or do I need to sit to recover faster?

Taking Fido along for a hike in the woods can be rewarding and fun, but you need to be prepared in the event of an unexpected emergency

I read that the human sleep cycles last 90 minutes, so people are more rested if they sleep in increments of 90 minutes—7.5 hours, for example, is better than eight. Is that true? And what about sleeping for 4.5 hours at night, then supplementing with a few 90-minute naps? Is that the same as sleeping for 7.5 hours?

When I was in college, the head of athletics held an all-team meeting at which he said that every alcoholic drink we had would set us back a week of training. True or false?

Tens of thousands of people are hurt while riding their bikes every year in the United States alone. Follow these 10 basic guidelines to make sure you avoid injury and stay safe.

We asked three hard-charging Outside readers how they manage to stay supremely fit while balancing work and family. The secrets to their success are easier than you think.

Our best writing on America's obstacle racing craze and the personalities behind it

Lance Armstrong allegedly doped and won seven Tour titles. So if I dope, I should at least dominate some local races, right?

In Argentina, rival soccer fans don’t just hate, they kill, and the violent partisans of top clubs fuel crime syndicates that influence the sport at its highest levels. Patrick Symmes braves the bottle rockets, howling mobs, urine bombs, and drunken grannies on a wild ride through the scariest fútbol underworld on earth.

The obstacle course craze is taking over America. This year some 1.5 million people will enter an event. But behind all the dirty fun is a nasty business and legal battle between entrepreneurs looking to cash in. Here, in a preview of Outside’s November cover story, is a glimpse at just how far they’ll go to sell you their brand of pain.

I always get sausage fingers and puffy hands whenever I go on day hikes. My friend says it’s because I’m not eating enough salt. But doesn’t salt cause bloating? What’s going on here?

I’m running the Twin Cities Marathon in October. I’ve been getting a massage about once a month while I’ve been training, but I'm not sure when to schedule my final massage before the race for optimal performance. Got any tips?

Sometimes winning just means not losing any blood

I was about halfway through a 17-mile run in preparation for a marathon. I was wearing a hydration belt that contained a cell phone, mace, endurance beans and two 10-ounce water bottles. During the run, a man on a bike pulled up to me and told me that I was going to "ruin my back" carrying that much weight. While I haven't done 100 marathons, this isn't my first time. I have been working hard to keep my core strong, and I try to position the weight so I carry it on my hips. Is he right?

I’ve seen conflicting reports on whether it’s better to exercise in the morning before or after breakfast to promote weight loss. Which is it?

A rundown of the biggest moments of the 2012 Paralympics in London, from conflicts to triumphs. https://youtube.com/watch?v=6SLxh0ceP70 10. Armless Archer Wins a Silver MedalWhen Matthew Stutzman, 29, first became interested in archery, he Googled, “How to teach a guy without arms how to shoot a bow.” Nothing came up.

File this one under fun: Cal Coast Track Team Daily Jump. Photo: The Daily Jump We recently caught wind of a new DIY fitness trend that’s going viral. You can do it anywhere, anytime, with anyone. By yourself. On a trail. with your kids in…

There can be only one super-specific, outdoor sport

I watched Jen Kessy smack gum throughout her Olympic beach volleyball matches. Can gum help performance, or does Kessy just have really bad breath?

Fitness magnate Bahram Akradi is buying up some of the most beloved endurance events in the country—and he has plans to improve them. So what's everybody afraid of?

All of my non-cotton workout clothes reek after I workout. What the heck? Are there any technical workout clothes that won’t hang onto my B.O. for eternity?

When’s the best time to use a foam roller, before or after a workout?

Can I convert my fast twitch muscles to slow twitch muscles and vice versa?

David Hill thought he was joining a bookstore-sponsored basketball league in Brooklyn, but it turned out to be a lot more than just thick-framed glasses and set shots

The U.S. men's soccer team made history against Mexico last night. But what makes one win so impressive?

I got heatstroke in a running race two years ago and passed out. Am I more likely to get it again than someone who’s never had it?

My lower back can can get stiff and sore between workouts. Will sitting on an exercise ball while at work help me to strengthen it?