Feel the burn in your thighs, calves, arms -- everywhere, really. These hour-long workouts can help build up your endurance and your strength from head to toe:
• $38.99 ($120 value) for one month of unlimited CrossFit classes
• Classes are scheduled daily
These dynamic programs feature squats, lunges, kettlebell swings, battle rope drills, and more. Since the lineup of exercises is always changing, your body won't know what to expect -- that means muscles can continue to develop at a pace you'll love.