HOW TO DO IT: Assume a wide sumo stance with your feet farther than shoulder-width apart and your toes pointed out slightly. Drop your weight into your heels and lower your hips until your palms reach the box without rounding your lower back. Jump your feet back into a plank. Reverse the movement and repeat for 30 to 60 seconds. Add height to the box if the movement is too difficult.
It boosts immunity. Regular exercise can reduce your risk of certain serious health conditions, including heart disease, diabetes and some cancers. It can also decrease your chances of developing -- and getting stuck with -- more common illnesses, such as flus and colds. (According to one recent study, colds lasted 43 percent longer for people who exercised once a week or less.)
“Push-ups are a great exercise that can be done regressively or progressively. Adding things like shoulder taps, mountain climbers, or even negatives are great ways to add more effectiveness to push-ups done without weight,” explained Septh. Similarly, Barajas mentioned a change simple as switching up your hand placements (wide, narrow, etc.) will work different parts of the muscles.
The workout includes a dynamic warm-up to get your blood flowing and prep your body for the rest of the work ahead, and a cool-down to help you slow back down and wrap it all up. If you want to make the workout more challenging—maybe you've done it a handful of times and are ready to turn things up a notch—add weights to the lunge and squat movements. You can also, like Sims said, add another round of the main strength circuit.
It decreases PMS. Women often report feeling irritable and bloated before their periods, but exercise appears to minimize these conditions. In a survey of nearly 2,000 New Zealand women, researchers found that those who exercised, rested and wrote in a journal about their symptoms fared better than those who took specific vitamins or followed other DIY advice.
Essentially, circuit weight training, or circuit bodyweight training, burns more calories than interval training, and that in turn burns WAY more calories than steady cardio. When you strength train, you burn calories. Then, your body needs to spend hours and hours afterwards rebuilding your muscles, which in turns burns even more calories (they call this the ‘afterburn effect).
The skin also serves as a release point for heat. (See “Why Does My Face Turn Red When I Exercise?” for more on that.) When you exercise, your muscles generate a lot of heat, which you have to give up to the environment so your body temperature doesn’t get too high, Hackney says. The heat in the muscle transfers to the blood, which shuttles it to the skin; it can then escape into the atmosphere.