Interval Training

This hard-hitting session will increase your endurance and agility while delivering some new muscle and definition to your back, shoulders and arms.

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These time-efficient, hard-HIITing plans use free weights, machines and your bodyweight to help you get your sweat on.

There's no getting around it: Hill training is rough. But if you do it correctly, it's worth it.

These tips can help you make the most of your HIIT workout.

Try David Siik’s precisely calculated treadmill system to engage your mind, preserve your joints and burn a ton of fat in less than half an hour.

Build strength and shed bodyfat fast with these two high-intensity interval workouts.

This winter, you may find yourself looking at more indoor cardio. Try these four time-to-sweat workouts.

Oxygen’s fat-melting interval plan will get you ready to feel the heat — and see results!

In Month 3 of The Ultimate Oxygen Challenge Erin Stern introduces Tabata. Watch as she performs her circuit in real time!

Use high-intensity interval training to reveal awesome abs. Try these three do-anywhere routines.

Determining your optimal work-rest intervals for HIIT.

High-intensity interval training (HIIT) is an effective and time-saving training method, but is it possible to overdo it?

Science supports it, your body responds to it and it saves you time. Learn the truth about high-intensity interval training, and hop aboard the interval bandwagon.

Get the most out of your cardio workout with these two high-intensity interval routines.