30-Minute Treadmill Workout

Be prepared to sweat with this killer treadmill workout [7], designed by the mastermind behind Equinox's Precision Running [8]! You can tailor it to fit whatever level of fitness you're currently at by modifying the speeds however you see fit. Keep in mind the whole workout is intervals, so pace yourself in the beginning so you don't burn out too quickly.

20-Minute HIIT Circuit

After a quick warmup, this 20-minute workout [9] focuses on cardio moves that will strengthen your legs, but we threw in a couple of core moves for good measure. Illustrated with GIFs, this workout is easy to follow and fun to do. Get ready to sweat!

30-Minute Tabata

Tabata is a form of HIIT that alternates between 20 seconds of intense bursts of work and 10 seconds of rest in four-minute rounds. This 30-minute video [10], which treats you to a few rounds of Tabata along with a warmup and cooldown, hits every muscle while burning serious calories.

45-Minute Belly-Shrinking HIIT Workout

This is a Tabata workout [11], which is a form of HIIT, and it's proven to help diminish belly fat [12] better than steady-state cardio. Each four-minute section of this workout involves eight rounds of 20 seconds on and 10 seconds off. What makes this workout so intense is that it's long: 45 minutes total! [13]

Equipment needed: jump rope (or just pretend!) and a set of medium-weight dumbbells

30-Minute HIIT Workout

If running isn't helping you lose weight, do this 30-minute HIIT workout [14] instead. It involves alternating between burpees and classic strength-training moves like kettlebell swings.

Jump Rope HIIT and Strength-Training Workout

You'll get it all in this one workout [15]: HIIT cardio and strength training. Just grab a jump rope; the rest is done with your bodyweight. If you're sceptical about using a jump rope to get in a good workout, just trust us. You'll sweat your butt off.

HIIT Workout From Revenge Body Trainer

Corey Calliet, Michael B. Jordan's trainer who appeared on Revenge Body, gave us an exclusive HIIT workout [16] he does with his clients. All you need is a box or platform to do your box jumps and the rest is bodyweight movement.

Seated Russian Twist

• Sit on the ground with your knees bent and your heels about a foot from your butt.
• Lean slightly back without rounding your spine at all. It is really important, and difficult, to keep your back straight, but don't let it curve.
• Hold a weight or a medicine ball just below your chest. Keep the weight close to you and progress by moving weight further away from your body.
• Pull your navel to your spine and twist slowly to the left. The movement is not large and comes from the ribs rotating, not from your arms swinging. Inhale through centre and rotate to the right. This completes one rep.
• Do 16 full rotations.

Pilates Corkscrew

• Lie on your back and pull your knees into your chest. Reach your legs up to the ceiling, and tightly squeeze them together, focusing on connecting your inner thighs.
• Reach the legs over to the right, allowing the hips to lift away from the floor.
• Reach the legs back to centre but still engaged, ensuring that the lower back remains on the floor.
• Reach the legs over to the left, grounding the shoulders and allowing the hips to move first, the rib cage if possible next. Pull the legs back up in toward the body. This counts as one rep.
• Repeat 10 times.

This classic Pilates move strengthens your obliques, core, and legs, while stretching your hips away from your ribs.

Plank and Rotate

Twisting in a plank position fires up the core and works those love handles.

• Begin in a plank position holding a five-pound dumbbell in each hand, keeping your wrists stiff to protect the joints. Open your feet a little wider than hip distance.
• Lift your left hand to the ceiling, twisting through your entire torso. Your pelvis will rotate, but keep it level.
• Bring your left hand back to the floor, and repeat this action on the other side to complete one rep.
• Do 10 to 15 reps to complete a set.

Use five- to eight-pound dumbbells.

Birdog

• Get on all fours, with your knees under your hips and your hands under your shoulders. Remember to keep abs engaged and keep your back flat.
• Reach out with your right hand and extend your left leg out behind you.
• Round your back and head to connect your right elbow with your left leg under your body. Extend right hand and left leg back out.
• Repeat for a total of 15 times, then switch sides.

See the quadruped in action here [17].

Ball Pike to Plank

Make sure the ball is sized to your body; you should be able to sit on the ball with 90-degree angles at your hips and knees.

• Start in a plank position with your hands directly under your shoulders and your shins on the ball.
• Do not allow your lower back to arch. Keep your feet, pelvis, and shoulders in one long line.
• On an exhale, pull your abs deeply to your spine and use your abs to fold your body in half, pulling the ball forward toward your hands as your pelvis moves up in the air.
• Your toes will move onto top of ball and your back will become perpendicular to the floor like a handstand. Allow your head to fall between your arms, keeping your neck long and in line with your spine.
• Lower yourself back into a plank position and do not allow your pelvis to sag below your shoulders.
• Do 10 reps for two to three sets.

Alternating Two-Point Plank

• Start in a plank position with your hands directly under your shoulders and your feet in line with your hips. Lift your left leg off the ground so your heel is even with your pelvis.
• Keeping your torso steady, reach your right arm forward. Really brace through your abs by pulling your navel to your spine. Hold this position for about three seconds. It's harder than you think!
• Return to plank, then switch sides lifting your right leg off the ground and reaching your left arm forward. Hold for three seconds and return to plank. This is one rep.
• Do two to three sets of 10 reps each.

Plank With Bunny Hop

• Begin in a plank position with feet touching.
• Pull your abs in, and jump your feet to the right, bringing your knees toward your right elbow. Your torso will twist to the right.
• To complete one rep, jump your feet back to plank.
• Repeat on the other side and continue alternating sides for 20 reps total.

Kettlebell Windmill

• Begin standing with your feet slightly wider than hip distance apart.
• Rotate your left toes outward and raise your right arm above your head, keeping your eyes trained on the weight.
• Shift your hips to the right. Don't let your pelvis swing behind you as you move into the sassy position.
• As you shift your hips right, your weight will shift to the right, too. You should feel about 60 percent of your weight in your right foot.
• Lower your torso toward the floor, so the kettlebell hovers just off the floor.
• Keep your body as flat as possible, with the ankles, hips, and shoulders in one plane. This position feels a lot like a tight Triangle pose in yoga.
• Keep your torso still as you bring your left hand to your left shoulder in a biceps curl.
• Keeping your left arm bent and your right arm pointing to the ceiling, come to standing position. Imagine your waist doing all the work to move your torso upright.
• Shift your pelvis back to centre once again to distribute your weight evenly between both feet.
• Complete the rep by bringing your left arm overhead, working your shoulder. Lower your left arm down to return to starting position, and repeat.
• Do three sets of eight to 10 reps on each side.

Follow our step-by-step tutorial of the windmill [18] to learn the subtleties of the exercise. Don't worry if you don't have kettlebells — you can use dumbbells, too.