Isotonic routines require no equipment; just make sure you remind the students to fully engage (tighten) their muscles to get the maximum benefit. Have students stand. Engage the biceps by making a tight fist and do 20 biceps curls. Next, have them raise their arms straight out to the sides at shoulder level, engage their shoulder area, and lower arms on a 3-count, then lift them back up to shoulder level on a 3-count. Do 20. Then, have students tighten their abs and alternate touching right elbow to left knee and right knee to left elbow for 30 lifts. Repeat the entire routine one or two more times.