Set the height of the TRX straps so that you can sit beneath them and only just reach the handles with outstretched arms. With your hips directly under your shoulders and an upright torso, take grip of the handles. Focusing the tension in your lats and arms pull your body upwards, exhaling as you do so. Aim to get your upper chest to the same level as the handles. Hold the top position for a second, and then lower your body back to the start position, inhaling as you do so. Try not to use your legs to aide you.