Select the appropriate weight matching your type of training and your fitness level. Lie down on an incline bench and secure your legs at the end. Grab the dumbbells with an overhand grip. As you are lying down, extend your arms and bring both dumbbells above your chest. Palms holding the dumbbells are facing each other. Your elbows are slightly bent.
With a slight bend on your elbows, lower your arms at both sides. Continue until your shoulders are at the same level with your wrists, your elbows slightly below your shoulders. Keep your wrists in the same position without any rotation. Contract the chest muscles as you go up to the stretch above your chest from the lower position. Continue going up (arm extension) until both dumbbells touch each other in the upper position. Maintain the correct stance without bending your back backwards (lumbar lordosis). Breathe in as you go down; breathe out as you go up.
Do not over overrate your capacity while selecting the appropriate weight. Be careful about correct positioning of your hands and keep your elbows slightly bent at all times, especially in the lower position. Make sure you avoid straining your lower back; both your chest and entire torso must be straight and firm all the way through. Eliminate using your upper trapezius muscles.
It is advised to use a spotter, especially if you are working out with heavier weight. Choose the number of repetitions to match your training type.
Decline dumbbell flyes are supposed to strengthen the inner lower part of pectoralis (chest) muscle.
The movement itself is damaging the shoulder joint and rotator cuff. Out of that, a study by Barnett and colleagues from 1995 showed that decline bench has no advantages over flat bench – the lower pecs are better worked on flat bench.
If you still wish to do this exercise pay special attention to how deep do you lower the dumbbells. Do not lower them too much, this is exactly the position creating huge stress on your shoulders.
Keep pressure on the muscles during the whole set.