1. Stand in front of a line (preferably two feet long) and start jumping back and forth over the line.
Each muscle is made up of thousands of fibers.
President's Council on Physical Fitness and Sports. 701 Pennsylvania Avenue, NW. Suite 250. Washington D.C. 20004
The President's Challenge. Poplars Research Center, 400 East 7th Street. Bloomington, IN 47405
Hand Drawn Illustrations by Mrs. Terry Burger, Art Teacher, Wyckoff, NJ