Find out how a strong lower back can transform workouts as you know them.
Never tried crossed-leg, behind-the-back leg lifts? Here's your chance.
Activate that yoga flow with quick bursts of cardio.
Sit-ups for leg strength? Try this video to see what we mean.
Put your legs in the air like you just don't care.
It's basically an entire gym—and a trainer—in a box.
At least you can stretch out beside the crackling fireplace after.
When you're sore the next day, you know it worked.
Wait, which side is up?
Swap the dumbbells for a kettlebell.