Calisthenics are simple exercises that you can do to keep fit and healthy. the American spelling of callisthenics (kallos + sthenos ). Systematic rhythmic bodily exercises (e.g., jumping jacks, push-ups), usually performed without apparatus. Calisthenics promote strength, endurance, flexibility, and general well-being by placing regular demands on the cardiovascular system. The exercises, initially conceived as primarily for women, arose in the 19th century in Germany and Sweden. Catharine Esther Beecher in the U.S. advocated women's calisthenics. As their health benefits became known, they became an activity for both sexes