Can Sex Improve Your Running Performance?

Here’s a compelling argument for getting racy before heading out for a run: 48 percent of runners under age 40 say that having sex before a race fueled their performance, according to a new survey of 1,000 male and female runners from Brooks Running.

Okay, so it’s not like this was a scientific poll or anything. But it made us wonder—can sex give your running workout an edge? The answer is a definite yes, says sexologist Yvonne K. Fulbright, Ph.D. First, sex is like any cardio activity, getting your blood pumping and your heart rate going. But since most sex sessions aren’t crazy physically demanding (which is why sex doesn't really count as a workout), it serves as kind of a warm-up to your run, heating muscles and joints and making you more flexy.

4 Things to Do Today to Sleep Better Tonight

In a perfect world, your dozing hours look something like this: As you kill the lights, receptors in your eyes signal your body to prep for the sandman. Your brain releases the snooze-inducing hormone melatonin, slows your heart rate, reduces your body temp, and puts a stop order on stimulating stress hormones like cortisol. After you fall asleep, you oscillate between light and deep slumber every 60 to 90 minutes; it's in the latter stage that your cells may fight off illness and recover from injury.

But if you had a hectic day, stress can trigger your brain to pump out excess cortisol, which may hurt your ability to power down, says Natalie Dautovich, Ph.D., an environmental scholar at the National Sleep Foundation (NSF). That means tossing and turning and a racing mind (Is my bank account overdrawn? Is my relationship on the rocks?). It also means you won't reach the deeper, restorative phases of sleep. Come morning, you feel like a vengeful member of The Walking Dead.

How His Childhood Eating Habits Affect His Boner

As you're probably well aware, there are quite a few reasons why a guy might not be able to get hard. From his relationship with his mom to weird masturbation habits, you might think you've heard it all—but you would be wrong. His erection troubles might also be to blame on how much sugar he ate as a kid, according to a recent study published in The Journal of Sexual Medicine.

For the latest boner-killing study, researchers gave newborn male rats water spiked with different dosages of fructose (the type of sugar found in fruit). The control group drank regular water, a second group drank water with five percent fructose, and the third group drank water with 10 percent fructose. After eight weeks, researchers tested the rats' blood-glucose levels, testosterone levels, and erectile function.

Are You a Sex Addict ... or Just a Guy?

Here's a shocker: Men love sex. Thinking about it, watching it, doing it—your day is probably sprinkled with sexual urges. How often? Ten, 20, 50 times a day? Is once every 10 minutes a reason to start worrying? Where’s the line between having a sex addiction ... and just being a living, breathing guy?

Studies have shown that as many as 1 in 25 people report an uncontrollable obsession with sexual thoughts, feelings, or behaviors. But whether sex addiction is even a real thing is up for debate. As it's clinically known, hypersexuality didn’t make the cut to be included in the newest version of the Diagnostic and Statistical Manual of Mental Disorders (DSM), the bible of diagnosing mental disorders. But if you were to ask Tiger Woods, a voracious sexual appetite is  a very real thing.

Sitting on Your Butt All Day Is More Risky Than Being Obese

Consider this your daily reminder to get off your bum: Being sedentary may be twice as dangerous as being obese, according to a new study from the University of Cambridge.

Researchers tracked over 334,000 people for 12 years and compared activity levels and weights among the subjects who died during that time. They calculated how many deaths could have been avoided if all the participants had been more active versus at a healthy weight, and determined that physical activity could have saved twice as many people as weight loss.

6 Ways You Kill Her Orgasm

She’s right on the edge of ecstasy, and then you do something dumb in bed that derails her pleasure, throws her off her game, and ruins the rest of the night. Some maneuvers may seem innocuous, but they actually distract her from her ultimate endgame: achieving orgasm. Avoid these six sex moves at all costs.

(And while you're at it, look out for the 5 Signs You Might Be Bad in Bed—and discover how to change both of your sex lives for the better.)

This is Why You Don't Have the Body You Want Yet

I've heard stories  about athletes who enhance their performance by sleeping in high-altitude chambers, drinking kale smoothies every four hours, getting deep tissue massages every day, or training with equipment that looks like NASA's castoffs. Great for them. But for most of us, just finding 20 minutes a day to exercise is an impressive feat.

That's why I remind the average guy to keep it simple. You don't need Space Age equipment when a barbell works just fine.  In order to make continuous progress and stay healthy, I've learned over the years that you just need to follow four principles. They're not earth shattering or original, but they work. Follow them, and you'll set yourself up for a lifetime of fitness success.

Why Men Suddenly Develop Pregnancy Symptoms When YOU'RE Expecting

This article was written by Ali Eaves and provided by our partners at Men's Health.

It's nothing compared to what women's bodies goes through—but men experience hormonal changes when their partners are pregnant, finds a new University of Michigan study. Researchers tested the hormone levels of first-time fathers-to-be and found that their testosterone dropped as the baby grew.

Don't panic—we're not talking clinically low T levels, says study author Robin Edelstein, Ph.D. But the changes could be just enough to subtly influence his personality, like making him more nurturing and devoted to you and your future child (not such a bad thing).