填空题

The fitness movement that began in the late 1960s and early 1970s centered (31) aerobic exercise. Millions of individuals became (32) in a variety of aerobic activities, and literally thousands of health spas developed around the country (33) capitalize on his emerging interest in (34) particularly aerobic dancing for females. A number of fitness spas existed prior (35) this aerobic fitness movement, even a national chain with spas in most major cities. However, their focus was (36) on aerobics, but (37) weight training programs designed to develop muscular mass, strength , and endurance in their primarily male enthusiasts. These fitness (38) did not seem to benefit financially from the (39) fitness movement to better health, since medical opinion suggested that (40) training programs offered few, if (41) , health benefits. In recent years, (42) weight gaining has again become increasingly popular for males and for (43) females. Many current programs focus not only on (44) muscular strength and endurance but on aerobic fitness as well.
Historically, most physical fitness tests have usually included measures of muscular strength and (45) , not for health related reasons, but primarily (46) such fitness components have been related to performance in athletics. However, in recent years, (47) has shown that training programs designed primarily to improve muscular (48) and endurance might also offer some health (49) as well. The American College of Sports Medicine now recommends that weight training (50) part of a total fitness program for healthy Americans.