>> push-ups. then jumping jacks for 20 seconds. >> you're actually going to do what's called skier flings. set your hips back, squeeze up. this is going to work the entire backside of your body. again, 40 seconds of that. super fast. >> watch out. watch out for that window. >> keep your arms straight. kick your hips back, throw them up. so you're squeezing your butt when you come up. kind of like the momentum carries the weight. it's really fast. then after 40 seconds of that, go back into jumping j ining ja. >> is this cross training? what is this? >> metabolic workouts. you're combining strength and cardio, which allows you to get a lot done in a short period of time. hinge at your hips, keep your