We all know the importance of varying your routine at the gym: doing the same set of reps over and over just doesn't do much good—and, what's more, it's just a bit boring. Changing things up can open up a whole new world of exercise opportunity, especially if you're open to the idea of including a partner in your workout. We've tapped two of Twistys' exercise experts to demonstrate some of the benefits of partnered weightlifting. It works wonders for the body—and believe us, it's anything but boring.. . . Click to view · Twistys (twistys.com)