Lie down with your back to the floor with one arm stretched #90º to the ground so that your hand are above your head. Stand up, always keeping your arm stretched above your head and perpendicular to the ground. Return to the starting position. Keep looking at the raised hand throughout this movement.
Count one repetition each time you stand up.
– Always keep the raised arm perpendicular to the ground.
– Alternate the arm that you raise in each repetition.
– Mountain climber