Christina Stiehl

What if a full-body workout was only a matter of hooking yourself up to a system of wires and electrodes, doing a few lunges and squats , and calling it a day? That seems to be the lofty claims of electric muscle stimulation, or EMS, machines, which promise to deliver a rigorous workout in just minutes of simple circuit training.

One purported benefit of HIIT is your body's ability to stay in fat-burning mode long after your workout is finished, which is music to the ears of anyone who follows their Saturday sweat sesh with a boozy brunch. Known as the afterburn effect, this process is said to rev up your metabolism and torch calories for up to 24 hours after exercise. But is this benefit too good to be true?

With their sleek aesthetics, club-inspired music, and cult-like followings, cycling studios have been on top of the trendy boutique fitness totem pole for the better part of the last decade, led by grapefruit-smelling, feel-good-mantra-spouting SoulCycle (which people seem to either love or hate). But there's a whole new game-changer beginning to take over the world of sweaty, sexy group workouts: indoor rowing.

Exercise doesn't exactly top the list of "most fun things to do with your free time." But it doesn't have to be the worst thing in the world. Take it from these people who used to despise working out, and now do it on the regular... and like it!

So, so wrong. Instead of spending money on a gym membership, what you really need is a month-long fitness challenge -- something that tells you exactly what to do every single day, no equipment or gym required. The Gym-Free Fitness Challenge consists of 30 equipment-free workouts (plus an initial assessment) designed to hit all the strength, cardio, and flexibility guidelines suggested by the American College of Sports Medicine. And it's totally free.

There's no magic secret to living a long life. Except maybe whiskey, which is something we can all get behind. But living healthfully into your 80s or 90s mostly requires a deliberate approach to incorporating common-sense, yet annoying habits like eating your vegetables, not drinking too much, and working out regularly.

You probably know to be extra careful when swinging around a heavy kettlebell, or to make sure the treadmill is completely stopped before hopping on; a broken foot or bloody nose can happen in no time, especially if you're clumsy. But there are some things that can go wrong, even when you have the best of fitness intentions. Here are some of the most pervasive dangerous workout myths, debunked.

Six-pack abs without exercise? Sleek and sexy legs with a few simple squeezes? Bulging biceps by just moving a ball thingy around? If it seems too good to be true -- and gives you some borderline-creepy vibes while using it -- it probably is.