If you're working out at home, start outside, going for a quick run to get your heart rate up. First, jog for two to three minutes, and as soon as you feel warm, run quickly — this should feel like a 7 or 8, out of 10, in terms of difficulty — for about five to 10 minutes. "This will get your heart rate way up so you burn tons of calories in the moves that follow, and get your body warm so you don't get injured," Lyuda told POPSUGAR.