HOW TO DO IT: Start in a high plank. Push your hips back without arching your lower back until your knees flex to about 90 degrees. Pause for a beat, then explosively extend through your knees, ankles and hips while also pulling with your upper back as you lower into the bottom of a push-up. Keep your elbows tucked into your sides to protect your shoulders. Skip the push-up and just maintain a hold if you need it to be easier.
Think you can’t get a good workout while you’re sitting? Think again. In fact, the seated lat pulldown is one of the best exercises for toning those arms in a hurry. Using a pulldown machine, grip the bar and pull to chest level, and then raise again. This exercise makes it easy to build your biceps quickly and helps strengthen and tone your shoulders, which can make your arms look leaner, as well.
Start the clock, and immediately do 10 pushups in perfect form. When you’re done with the pushups, go straight into jumping jacks until the clock reads 1:00. Then move on to the next move, spider lunges (total, not per side). Do 10 of those with good form, and then jumping jacks until the minute is up. Then move on to the next move — 10 perfect reps of the jumping lunges, and then do jumping jacks until the end of the minute. And finish up with 10 perfect walkouts.
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.