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. Once you are lying down, bring the dumbbells down to your sides with elbows slightly bent (to 90 degrees). Palms are facing forward (thumbs next to each other). Your shoulders and elbows are parallel.
Push the dumbbells up over your chest using your pectoral muscles. Continue going up until both dumbbells touch each other in the upper position. Keep your wrists in the same position without any rotation all the way through. 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. Make sure your hands are in the correct position and avoid extensive dorsal flexion in your wrists. 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 a heavier weight. Choose the number of repetitions to match your training type.
Decline dumbbell bench press is supposed to strengthen and build the lower part of the pectoralis muscle (lower chest).
This assumption is probably wrong considering the findings of 1995 study by Barnett and colleagues.