Get some cardio in by doing jumping jacks with a twist. It is Dumbbell February so that means we're including dumbbells. All you have to do is hold the dumbbells close to your chest, and do a regular jack opening and closing your legs. Try not to bounce your upper body back and forth as you jump. And note that my knees bend slightly and don't buckle as I land; this is to protect my joints. Do this for 3 rounds of 1 minute each. Mix it up with other cardio exercises.