We've put together the best squat challenges, featuring multiple squat exercises that tighten and tone. There's a reason everyone is still so crazy about squats: They're awesome for your glutes, thighs, and core, meaning you're burning caloriess and building muscles in one fantastic move. Take up our 30 to 100(!) Day Squat Challenges and tone up and boost your leg and butt muscles and body strength to the max and get into the perfect summer shape that you’ve been dreaming of for so long. In general, 30-day challenges are a great way to work on your fitness, because they give you an achievable (short-term) goal to keep you focused. The motivation to lose weight or get fitter is obviously great, but without something clear and defined to work towards, it’s all too easy to skip a session or two then slide back into inactivity. And of all the 30-day challenges you might try, a squat challenge is one of the best. That’s because the unweighted squat is a strong contender for the finest bodyweight exercise in town. It works almost every muscle in your lower body, hitting big muscle groups like the quads, hamstrings and glutes especially hard.