Join TODAY's Summer Shape-Up Challenge!

/ Source: TODAY

Want to get in shape for summer? Join TODAY's Summer Shape-Up Challenge! We've enlisted three TODAY viewers to participate on air, but you can follow along with them at home. One viewer will only follow Obi Obadike's exercise regimen, one will follow Joy Bauer's Drop 10 TODAY meal plan and the third viewer will do both.


By the end of the series we'll find out: Which is more important to lose weight, diet or exercise? Get started with these workouts! Obadike recommended working out four or five times a week, for 30 minutes at a time.

RELATED: Follow the Drop 10 TODAY meal plan

Bootcamp Cardio Routine:

Aim to complete this workout on Mondays, Wednesdays and Fridays. Perform four cycles of this routine from start to finish. Between each exercise, take an active 15-second rest by running in place.

RELATED: 5 easy moves to tone your body

1. High knees

Run in place very slowly, raising your knees as high as they'll go for 15 to 30 seconds.

2. Basketball jump shots

Jump up in the air like you're shooting a basketball for 15 to 30 seconds.

3. Jump over the towel

Jump over a towel back and forth, then from side to side for 15 to 30 seconds.

4. Squat upper cuts

Begin in a squat position stance and do boxing uppercuts for 15 to 30 seconds.

RELATED: The 1 full-body exercise you should do every day

Circuit-Training Routine

Try to complete this workout on Tuesdays and Thursdays. Perform four cycles of this circuit from start to finish. Take a 15-second rest after each exercise.

1. Standing shoulder dumbbell press

Start with your left leg forward, right leg backward. Holding the weights, face your palms outward while bending your elbows so the weights are at your head. Then push upward. About halfway through switch your legs. Repeat this movement for 15 seconds.

2. Squats

Start with your legs about hip-width apart, feet facing forward. Sit back as if you were sitting in a chair, but keep your back straight. Bend as deep as you can before returning to the standing position and squeezing your glutes as you come up. Continue for 15 seconds.

Nikki Bella demonstrates how to do the perfect squat in the video below!

3. Lunges

Again, start with your legs hip-width apart. Step one leg forward and bend both legs in a 90-degree angle. Repeat this movement for 15 seconds, but alternate legs as you continue.

4. Planks

Watch the video above for a detailed description of how to perfect your plank! But here are a few tips: Start with your elbows on the ground and feet together. Engage your core as you straighten your body into a line. Hold for 25 seconds.

Obi Obadike is a fitness expert and is the author of "The Cut: Lose Up To 10 Pounds In 10 Days And Sculpt Your Best Body."