The number of women in the military has grown significantly in recent decades. Women now make up about 14 percent of active duty forces, up from about 2 percent in the early 1970s. Their role has also evolved from the traditional concentration in medical and administrative occupations; women are now eligible to serve in over 80 percent of all military jobs, including many air, sea, and other combat-related positions. The growing role of women has also resulted in debate within and outside of the Department of Defense (DOD) over fundamental and sometimes contentious issues, including whether physical fitness standards are fair and appropriate to both men and women. The Defense Advisory Committee on Women in the Services reported that men and women at military installations across the country are confused about the need for differing standards among the services, particularly those regulating body fat, and lack confidence in the fairness of the standards. In addition, the Rand Corporation recently reported that some military men believe that fitness standards have been adjusted to the point of being too easy for women. Physical fitness is a fundamentally important part of military life for all military personnel. DOD guidance requires that servicemembers pass physical fitness tests at least annually regardless of age and gender. Personnel who fail to meet fitness standards can be denied promotions, schooling, and other activities and may be forced to leave the military. In recent years, the downsizing of active duty forces and the increased rate of deployments and redeployments for peace operations and other activities have increased the physical demands on soldiers. DOD’s guidance, issued in 1981 and updated in 1995, requires that the services establish physical fitness and body fat programs, which include fitness requirements for all servicemembers. The program guidance states that individual servicemembers need to possess the cardiorespiratory endurance, muscular strength and endurance, and whole body flexibility to successfully perform in accordance with a service-specific mission and military specialty. However, the guidance does not identify requirements for specific activities or levels of difficulty. In addition, the guidance states that maintaining desirable body composition is an integral part of physical fitness, general health, and military appearance. The Assistant Secretary of Defense for Force Management Policy is responsible for oversight of the program and coordinating with the Assistant Secretary of Defense for Health Affairs, who is responsible for establishing a health promotion program to be implemented in conjunction with the fitness and body fat program. DOD guidance states that each service must develop its own program according to its particular needs, placing primary emphasis on maintaining general health and physical fitness. Evaluation of individual fitness is an integral component of the program. DOD Instruction 1308.3 sets out a number of key requirements for this evaluation, including the following: The services must use physical fitness tests of cardiovascular endurance, such as running a certain distance within a specified time limit, and muscular strength and endurance, such as sit-ups and push-ups. All servicemembers are to be tested regardless of age. Testing standards may be adjusted for age and must be adjusted for physiological differences between men and women. All servicemembers are to be formally tested for the record at least annually. Efficiency or fitness reports must include comments if the servicemember fails to meet physical fitness standards. DOD’s instruction also sets out body fat control policies and procedures. The instruction requires the services to use a two-tier screening process. If a servicemember exceeds the weight parameters for his or her height in a screening table or the member’s immediate commander determines that his or her appearance suggests an excess of body fat, then the servicemember’s percent of body fat is to be estimated. To standardize as much as possible, DOD requires the services to use similar validated circumferential equations for the prediction of body composition. The men’s equation involves measurements of the neck and waist or abdomen. The women’s equation requires measurement of the hips, waist, and neck, but allows for optional measurements of the abdomen and wrist, and/or forearm. For both the fitness and body fat components of the program, servicemembers who fail to perform successfully against the established standards are to be given at least 3 months to improve. Servicemembers who have not progressed during that time are to be referred to medical authorities for further evaluation. If servicemembers continue to fail over time, they are to be considered for administrative separation under service regulations. Two kinds of physical performance requirements are placed on members of the military: job-specific physical performance standards that are applicable to particular occupations and general physical fitness standards that are applicable to all members regardless of their occupation. The purpose of job-specific physical performance standards is to ensure that those personnel assigned to physically demanding jobs are capable of performing the requirements of those jobs. On the other hand, the primary purpose of general fitness standards is to maintain the overall health and conditioning of personnel. As such, these standards are not intended to specifically enhance the performance of a particular service mission or job. Section 543 of the Fiscal Year 1994 National Defense Authorization Act required the Secretary of Defense to prescribe physical performance standards for any occupation in which the Secretary determined that strength, endurance, and cardiovascular capacity was essential to the performance of duties. The act required that any such standards developed were to pertain to job activities that were commonly performed in that occupation, relevant to successful performance, and not based on gender. In other words, job-specific physical performance standards would identify the absolute minimum level needed for successful performance in those occupations. Anyone in that occupation, regardless of gender, would be required to meet the same standard. In 1996, we reported on the development and use of gender-neutral occupationally specific performance standards in the military. Neither the Navy nor the Marine Corps had adopted occupational strength standards. Although the Army categorized each enlisted occupational specialty into one of five categories based on physical demand, it discontinued testing recruits’ physical capabilities to perform such activities in 1990 and had previously used the results of that testing only for counseling recruits about serving in certain occupations. The Air Force had categorized each of its enlisted occupations into one of eight physical demand categories. It used a strength aptitude test administered to recruits to screen out those who would be likely to have difficulty performing physically demanding jobs, but it did not incorporate the strength test into the required annual fitness evaluation for personnel in those jobs. The DOD physical fitness program involves more than just periodic testing against standards. Passing an annual fitness test is not synonymous with maintaining a high level of health and physical fitness. The research literature provides a large body of information linking physical activity to health and a variety of recommendations for the amount and intensity of exercise needed to achieve fitness. For example, organizations such as the American College of Sports Medicine and the Department of Health and Human Services recommend 20 to 60 minutes of cardiovascular exercises most days of the week at a moderate level of intensity—for example over 50 percent of the maximum heart rate—as well as resistance exercises to condition the major muscle groups for strength and endurance. Some groups also recommend exercises to maintain flexibility. Although these recommendations were directed at the general U.S. population, a 1998 National Academy of Sciences report recommended that DOD personnel follow a similar regimen. DOD guidance recommends that servicemembers engage in regular physical fitness training of about 1-1/2 hours, three times a week. Duty time can be authorized for such training. Research literature also supports linking body fat percentages, cardiovascular endurance, and muscular endurance to the overall health objective. For example, the 1998 report by the National Academy of Sciences indicates that increases in the percentage of body fat are associated with health problems and a decrease in some aspects of fitness. Individuals with excess accumulation of abdominal fat appear to be at increased risk for a number of diseases. Research has identified little correlation between performance on timed runs, push-ups, sit-ups, and other fitness tests and specific military task performance. According to the 1998 National Academy of Sciences report, the majority of the military’s physically demanding occupations involve occasional to frequent lifting and load carrying. However, the report found little association between performance on push-up, sit-up, and unloaded distance running tests, and lifting and load carrying ability. Researchers concluded that tasks, such as unloaded distance running, were rarely a part of a soldier’s military duties and that the larger body type required to excel at lifting, for example, was different from the leaner body type required to excel at distance running. The relationship between the percentage of body fat and task performance is more complex. Some research has found that the higher the percentage of body fat the lower the performance in running tests. However, research also shows that women recruits who failed body fat standards were stronger than their counterparts who passed. This situation presents a dilemma for the military: setting a high body fat limit favors selection of women who are strong but may lack optimum endurance, and vice versa. The Academy’s report pointed out that, to some degree, current body fat standards may discriminate against women who would be the most capable of performing jobs requiring strength, which might be the most critical for survival in a combat situation. In addition, the 1998 report by the National Academy of Sciences, as well as an earlier report in 1992, concluded that the “appearance” objective does not seem to be linked to performance, fitness, nutrition, or health. Research conducted in 1990 explored this relationship by having a panel of military officers and enlisted personnel rate the military appearance of 1,075 male and 251 female Army personnel in uniform, and then comparing these judgments to measures of the percent of body fat for each participant. The results were only a “modest” correlation (0.53 for males, and 0.46 for females), and the report concluded that factors other than body composition, notably subjective judgment, influence appearance ratings. The National Academy of Sciences reports recommended that the military should develop objective criteria with which to judge appearance if it deems such a standard necessary.