here's another. Have someone

out a coin at shoulder height. When they drop it, you throw as many punchs as possible, using both hands, extending each arm fully, before the coin hits the ground. It will do so in 3/4 second. Your reaction time to seeing it drop, if you are truly ready to start, should be 1/4 second or less. So you get .50 second in which to throw punchs. you should get 3-5 punches before the coin hits.