This explosive exercise works the big, powerful muscles around your glutes and quads, and sends your heart into overdrive, according to research from the University of Wisconsin. In the study, participants burned 81kj a minute and their average heart was 93% of its max for the course of a 20-minute workout. "The kettlebell swing works you so hard because it's not a movement you're used to," says strength coach Dan John. "You’re not super efficient at it, which taxes your body."
Moderate-intensity rope jumping—about 100 to 120 skips per minute—burns about 54kJ a minute, according to the Compendium of Physical Activities. This mode of exercise uses more muscle groups than jogging, and challenges your balance, and coordination—especially if you practice drills that require extra hand and foot skills.
Tabata Jump Squats
This four-minute miracle drill burns major calories both during a workout and after. In an Auburn University at Montgomery study, participants who did eight rounds of all-out jump squats—20 seconds of hard work, separated by 10 seconds of rest—burned 54kJ per minute and doubled their post-exercise metabolic rate for at least 30 minutes.
In a recent study comparing various workout styles, battling-rope exercises came in first in terms of total oxygen consumption and an average calorie burn of 41 kJ per minute.
Zipping along on skis delivers a better heart-pounding workout compared to running at about the same pace, thanks to the fact that the sport requires you to push with your lower-body and pull with your upper. In fact, a good cross-country ski session can burn more than 50 kJ a minute, according to the Compendium of Physical Activities. That explains why skiers consistently collapse in exhaustion at the finish line of Olympic races.