Think about how you feel doing your 12-3-30 routine on the treadmill versus during a high-intensity interval (HIIT) class. You probably feel like you could maintain that first one for a pretty solid ...

When you’re crunched for time and need to squeeze in a workout, it’s fair to want to get the most out of your effort. But while there’s been an ongoing debate about the merits of aerobic vs. anaerobic ...