This quick workout combines strength moves with bursts of cardio to target the lower body. Perform each exercise in the circuit for the specified time, and repeat the circuit twice for a 20-minute workout. Warm up and cool down for three to five minutes to complete your exercise session.

Around the World Lunges 60 seconds

Stand with feet hip-width apart and step forward with your right foot into a lunge. Return to standing. Step the same foot to the right as you lower into a side lunge with your right knee bent, bottom pushed back, and left leg fully extended. Return to standing and move into a reverse lunge by stepping your right foot behind you and lowering the knee to the ground. Repeat on the left, then alternate sides for the duration of the exercise.

Jump Squats 90 seconds

With the feet hip-width apart, sit back into a squat. Push yourself up as you jump and propel into the air. Land in the starting position and repeat.

Step Ups 60 seconds

With a 5 to 10 pound dumbbell in each hand, stand in front of a stair or small step stool. Step up onto the stair with your right foot. Tap your left foot on the stair, return it to the ground, and then return the right foot to the ground. Continue stepping with your right foot for 30 seconds, then repeat with your left foot.

High Knee Jog 90 seconds

Jog in place as you lean back slightly and lift your knees high towards your chest.

Squats with a Side Leg Lift 60 seconds

Stand with feet hip-width apart, then sit back into a squat. As you return to standing, extend your right leg out to the side and lift your foot off the ground. Lift only to the point where you feel your hip muscles engage. Hold for one count and return to the starting position. Squat and repeat on the left side.

Front Kicks 90 seconds

Stand facing forward. Lift your right knee to waist level, extend your leg, and kick your foot out in front of you. Lower the leg, then repeat on the left side. Kick more quickly to increase the intensity.

Weighted Calf Raises 60 seconds

Stand on the floor with a 5 to 15-pound dumbbell in each hand. Raise up on your toes as you contract your calf muscles. Lower and repeat.

Side Jumps 90 seconds

Place a jump rope on the floor or choose a point on the ground to serve as a line (such as a groove in the sidewalk). Jump quickly from side to side over the line, jumping high and moving as quickly as you can.

*When doing squats and lunges its important to practice safe form to protect your knees. Sit your bottom back as you squat, and lower your body straight down when lunging to ensure your knees do not push past your toes.

Lori Rice, M.S., is a nutritional scientist and author with a passion for healthy cooking, exercise physiology, and food photography.