Get into a half-kneeling position with your right knee down and left foot flat on the ground; the mini band should be around the front of your left foot, with the other side in your right hand. Keeping your back flat, lean forward slightly, and pull your elbow back and up, near your right hip. Lower arm back to start and repeat. Do desired amount reps and then switch sides. 

These small, portable pieces of rubber don't get nearly enough credit: They can be used for overall body strengthening by creating levels of tension on your muscles, and can increase mobility. They're also low-impact and joint-friendly. Basically, mini resistance bands are an all-in-one gym that can be easily stowed in your closet or taken with you on the go.

Right now—while many of us are still under stay-at-home orders—is the perfect time to take advantage of mini resistance bands with this 21-day challenge to help build strength and gain mobility. All you have to do is grab a mini band (pick your own resistance, but make sure to have a few levels on hand), carve out an exercise space at home, and follow the instructions below. This way, when you're finally able to go the gym again, you may be even stronger than you were before COVID-19 hit—or maybe you'll decide you don't need a gym at all to get in a good sweat.

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Over the course of 21 days, you'll alternate working your upper body, lower body, butt, and abs (with rest days worked in, of course). Each day, do 3 sets of 12-15 reps for each exercise listed. On the final day—day 21—you'll do a "Total Body Burner," during which, you'll choose one exercise from each category (upper body, lower body, butt, abs) and do each move for 45 seconds, back to back, for 3 rounds, resting for 60 seconds between each round. See below for examples and directions of each move in this 21-day challenge.