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No-Fuss vertical jump Programs
For the back of your arm try kickbacks; hold a dumbbell in one hand while bent over slightly at the waist and raise the dumbbell up and behind you while keeping your elbow tucked into your side.
Take a belt or any piece of rope and tie one arm to your body. There is also the multiple contact opportunity that can be seen as a disadvantage because you might have to wait a few hours to get an answer.