Want to work out with the trainer who keeps the Sports Illustrated models in tip-top shape? Then Justin Gelband is your man. Dubbed "the model whisperer," Justin has prepped many models - including the Victoria's Secret Angels, along with the swimsuit models for the iconic annual issue of SI - for the runway and major photo shoots. Learn his fitness philosophy while toning your abs and butt with this 10-minute workout. You don't need any equipment for this sweat session, so no excuses! Press play and get ready to tone.