You've seen the 30-day squat challenges, but do they work? The what, why and how of squats

Once again, 30-day fitness challenges are all the rage on social media. Whether it's a family workout challenge, a flat-abs-in-30-days challenge, or a popular 10-minutes-of-yoga-a-day-for-30-days challenge, fitness influencers keep pushing new workout ideas − usually contained within month-long windows.

Among the most popular challenges today is the 30-day squat challenge, which pushes participants to dedicate a few minutes each day to mix up basic squat movements with more advanced ones while keeping in some rest days. 

Whether you're taking on the 30-day squat challenge or are just looking to implement a new movement in your workout routine, experts weigh in on body squat techniques and the health benefits of the exercise.

How to do squats

A body squat is a lower body strengthening exercise performed by squatting down from a standing position. It's popular, in part, because it's often a bodyweight movement alone and usually requires no equipment. Plus, doing it requires very little space yet still provides a meaningful workout. 

Squats are performed by standing with one's feet shoulder-width apart, placing hands behind one's head as if doing sit-ups, then lowering the body until one's thighs become parallel to the floor and then returning to the original standing position. 

The movement is usually repeated over multiple reps and can be amplified by adding leg kicks between squats, by using resistance bands or holding a weighted barbell against one's shoulders, by standing with feet wider than shoulder-width apart, or by reaching one's arms high and low with each knee bend up and down. Some people also choose to jump with each movement upward, allowing their feet to lift off the floor to bring more cardio into the exercise.

What muscles do squats work?

While different squat variations may target additional muscle groups, the primary exercise works one's "quadriceps and gluteus maximus muscles to regulate your descent and bring you back up," explains Loren Fishman, MD, a professor of physical medicine and rehabilitation at Columbia University and the medical director of Manhattan Physical Medicine and Rehabilitation. "To squat, you also need the adductor and abductor muscles to hold the legs in place and the iliopsoas to fine-tune your descent and keep you in balance," he adds. 

Quadriceps are the muscles at the front of one's thigh, the iliopsoas muscle is the major flexor of one's hip joint, abductor muscles help with leg rotation, and adductor muscles are in one's groin region and are mostly used for bringing the thighs together − a movement known as adduction. 

Squats also target the muscles along the back of one's thigh (hamstrings), and one's calves, though butt and thigh muscles get the best workout from the exercise. 

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What are the benefits of body squats?

In addition to being a great way to target and grow specific muscle groups, squats also burn calories, get one's heart rate up, and can enhance the power, strength and endurance of lower body muscles. "The movement also strengthens your tendons, bones and ligaments around the leg muscles," explains Michael Fredericson, MD, director of the Physical Medicine and Rehabilitation division of Stanford University. "And it helps with stability around the knees, which is why it's a critical exercise to do when recovering from a knee injury."

Squats also enhance bone density in the spine and lower body area, says Fredericson, and they improve one's flexibility as well − benefits especially important for older adults. "Your tendons, muscles, and ligaments become less elastic as you age. Doing squats can help slow down this process and keep you flexible," Fredericson says. 

One caveat of doing body squats is to make sure your form is right and that you aren't trying to carry too much barbell weight if you aren't using your bodyweight alone. Another tip to avoid injury is to make sure your knees never get closer together than shoulder width apart as failing to do this will put excess strain on your knees and hips. Also avoid letting your chest sag as keeping that area tight and upright, plus breathing in on the way down and out on the way up, will further help avoid lower back injury when performing the exercise. Some people also choose to support their lower back and help maintain form with the help of a back brace or weightlifting belt. 

"Squatting offers many benefits for overall fitness and daily mobility," says Fredericson, "but only provided you use proper form."