Warm up for about 10 minutes. Do some light aerobic activity and a few dynamic shoulder stretches, such as arm swings or circles.
Lie face down on the floor and extend your arms straight out in front of you, about shoulder-width apart, so your arms are aligned with your torso and your palms face the floor.
Grasp a ruler or a similar straight object in both hands. Keep your arms extended with your elbows locked and your wrists straight. Place your chin on the floor and keep it there throughout the test.
Lift your arms straight up, without bending your wrists or elbows, while you keep the ruler parallel with the floor. Have a training partner measure the distance from the bottom of the ruler straight down to the floor.