WHAT HAPPENS WHEN YOU OVERWORK YOUR MUSCLES?

Materials: pencil and paper watch with second hand

Experiment: a) Open one of your hands up as much as you can. Close that hand quickly to make a tight fist. b) Repeat opening and closing your hand like in "a" for one minute not stopping and remember to do it as fast as you can handle. c) Count and record what you can do during the first 30 seconds and then what you can do during the last 30 seconds. 1. How does you numbers from the first 30 seconds compare to the last 30 seconds? 2. Do you think it would make a difference to switch hands? 3. Do you think you would have been able to make more fists if you had gone slower? 4. If you do the experiment again with the same hand, do you think you would be able to make as many fists? 5. If you can't make the same number of fists in the second try, how long do you have to wait until you can?

This and many more experiments can be found in the book Science in Elementary Education by Peter C. Gega and Joseph M. Peters (Merril/Prentice Hall,Upper Saddle River, New Jersey, 1998. 8th Ed.)

Cole, Joanna. The Magic School Bus Inside the Human Body.

Gega,P. & Peters, J. Science in Elementary Education.

Lauber, P. Who eats what? Food chains and food webs.

Rubbel, David. Scholastic Kids' Encyclopedia: Science.

Showers, P. What happens to a hamburger?