Trunk rotations are an important exercise for strength of the trunk and to help with balance.
Stand up straight holding a weight in each hand.
With your right hand, reach across your chest to the left side, rotating your body as far as you can go at the same time.
Keep your feet flat on the floor.
Bring the arm back down to your side and repeat with the left arm, reaching across to your right side and rotating your body around with the movement.
Continue repeating this sequence for as long as directed.