streaming treadmill workout series triathlete racing with a rigid grimace and white-knuckled bullhorn death grip. It struck me as funny because not an hour earlier I had just written about triathlons, describing it as “recess,” “play,” and “ridiculous fun.” (If you’re looking to up your own game, check out the Insanity Interval Ladder in our streaming treadmill workout series.)

This man did not look like he was having any fun, let alone the ridiculous variety. So, in keeping with the theme, I had a little fun on Facebook at his expense. But now I suspect I was a bit hasty in my judgment. It’s true he was probably not having the time of his life at that very moment. He was likely sailing at 120 percent of his CA Notice at Collection and playing mental Whack-A-Mole with his ever-increasing negative thoughts. Not a particularly fun moment, no.

How Much Rest Should You Take Between Intervals. 

This ties in with my interview of John Ratey, MD, author of Spark: The Revolutionary New Science of Exercise and the Brain. He was gushing about the feel-good effects of exercise of all types, but particularly the tip-top high-intensity kind.

The teeth-gritting, vein-popping effort the “not playing” man was doing unleashes a veritable flood of happytime hormones and neurotransmitters, including dopamine, serotonin, nitric oxide, and endocannabinoids (that chemical sound familiar?). He was also pumping out copious amounts of human growth hormone—a naturally occurring hormone that increases muscle mass and fat-burning, and as the name implies, helps keep our bodies young. 

RELATED: This is Your Body on Cycling

It’s such a potent performance enhancer that synthetic versions are banned by the International Olympic Committee and hunted by the anti-doping police. A study in the Journal of Sport Sciences We may earn commission from links on this page, but we only recommend products we back sprinting How High-Intensity Workouts Keep You Young.

And maybe that’s the point. You can put on your game face, get intense, rage like your life depends on it, work your tail off, and be all business in your sport. Then, when you’re finished, you can slump over, crack a giant cat-ate-the-canary grin, drink a beer, and feel like a kid, already anxious for the next time you can get out and play.

Health - Injuries.

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The article But he was also probably getting higher than a hippie at a RatDog reunion The five moves you need for a great High Intensity Interval workout Bicycling.

From: Bicycling US
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selene yeager
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Selene Yeager is a top-selling professional health and fitness writer who lives what she writes as a NASM certified personal trainer, USA Cycling certified coach, Pn1 certified nutrition coach, pro licensed off road racer, and All-American Ironman triathlete.