Warm up before doing dumbbell pullovers. Walk briskly for 5 minutes, do jumping jacks or ride an exercise bike.
Spread a yoga mat out on the floor and stand the dumbbell on end at the top of the mat. Lie down on the mat with your back and feet on the floor, your legs bent and your head at the same end as the dumbbell.
Extend your arms overhead and grasp the underside of the top weight of the upended dumbbell. Your palms should face up, with your fingers and thumbs overlapping to support the weight.
Exhale as you lift your arms straight up. Stop the lift when your hands are directly over your chest. The dumbbell will be hanging down, pointing at your sternum.
Inhale as you lower your arms back to starting position. Do not set the weight back down; allow it to hover about 1/2 inch above the floor.
Repeat the pullover as many times as possible until you feel muscle fatigue. Work up to three sets of 10 to 15 repetitions.