Set a bench at an incline and sit with your chest against the back rest and your legs either side of the bench. Hold a dumbbell firmly in each hand and your arms extended on either side of the bench toward to the floor. This is your start position. Keeping your chest against the bench and your elbows close to your body, pull the dumbbells up and back towards your hips. Squeeze your back muscles as you do and exhale. Hold for a count of one before returning to the start position. Inhale as you do so. Repeat for the required reps (or time).