The 28-Day HIIT Challenge – Day 6

Each set in this workout is engineered to work as many muscle groups as possible, super-charging your metabolism. Remember form is especially important – quality trumps quantity! Sprint Cross-Country Seal X-Jack Mountain Climber Squat Reverse lunge Squat Jump Jump Lunge Power Knee Burpee Tiger Push-Up

The 14-Day HIIT Challenge – Day 6

Do each set three times. Rest for 30 seconds after each set. Squat Rotated Donkey Kick Lateral Sweep Reverse Lunge Rotated Donkey Kick Lateral Sweep Star Squat Pedal Grasshopper

The 7-Day HIIT Challenge – Day 6

Rest for one minute after each round. Sprint Mountain Climber Cross Jack Crab Touch Side Suicides Tiger Push Up Skater Jump Russian Twist