Tight on time? Can’t hit the gym? Don’t let anyone fool you into thinking you can’t still add some muscle and burn fat at home. Enter this single dumbbell HIIT workout from Strength and Conditioning Coach Jeff Cavaliere, Founder of popular YouTube channel Athlean-X. Not only will it leave your metabolism charged and build total body muscle (if eaten alongside a good diet, of course), but it’ll only take you 16 minutes. No dumbbell? Grab a kettlebell instead.