A man is instructing in a gym how to properly lift certain weights for the arms.
A man is in a gym and showing how to do a exercise with the arms.
A person uses a piece of equipment to exercise while other people exercise and move around in the background, and one person drinks from a drinking fountain.
A man is giving a demonstration of how to lift weights properly.
A man in a gym showing how to pump weights with a machine.
In a gym, a man is explaining how to work on arms while he is performing the action.
A group of people are in a gym, one man is talking and showing  how to work out his arms.,
A man in showing how to perform a certain exercise on equipment at the gym.
A man demonstrates how to do an exercise for the arms using a pull down weight machine.
A man at the gym is demonstrating how to correctly do tricep press downs.