For fitness enthusiasts who need a little cardio variety, HIIT (or high-intensity interval training) has long been a popular ...

Keep scrolling for 21 great high-intensity workout options to try that range from five to 45 minutes and include all different protocols. Note that since HIIT has such a broad definition we used ...

This 4-minute routine is designed to push your heart rate up, engage multiple muscle groups, and maximize fat loss. Unlike steady-state cardio, which primarily burns calories only during the workout, ...

Because the best HIIT workouts aren’t meant to last longer than 30 minutes or so, they’re mega efficient for honing your muscles. No gym? No sweat. (Actually, there will be lots of sweat.) ...

Set up interval training workouts the right way with these expert tips. But instead of putting together a 30-minute, non-stop workout, break up your program into shorter all-out intervals with ...