Change in anthropometrics and physical fitness in norwegian cadets during 3 years of military academy education

Introduction: High physical fitness is associated with increased occupational performance, better health, and reduced risk of injuries in military personnel. Thus, the military emphasizes physical training to maintain or develop physical fitness in their soldiers. It is important to monitor the effect of the physical training regime, but such information is lacking for Norwegian military cadets. Hence, the primary aim of this study was to investigate changes in anthropometrics and physical fitness among male and female army, navy and air force cadets during 3 years of military academy education. Materials and methods: 260 male and 29 female Norwegian cadets from the army, navy, and air force academies volunteered to participate. Anthropometrics, muscular power, muscular endurance, and maximal oxygen uptake were measured at entry (T0) and end of each year (T1, T2, and T3). Linear mixed models were used to examine the development in anthropometrics and physical fitness. We applied to the Regional Committee for Medical and Health Research Ethics to review the study before start-up, but the study was considered exempted from notification. The study was reviewed and approved by the Norwegian Social Science Data Services. Results: Male and female cadets significantly increased their body weight, fat-free mass, body mass index, and percent body fat by 1 to 5% from T0 to T3. Skeletal muscle mass was unchanged. Muscular power (medicine ball throw and vertical jump) and muscular endurance (pull-ups and push-ups) increased by 3 to 20% in male cadets, while female cadets only increased results significantly for the medicine ball throw (10%). Relative maximal oxygen uptake decreased by 4% in both sexes, while absolute maximal oxygen uptake only decreased significantly (by 2%) in male cadets. Most of the observed changes were classified as trivial or small, according to calculated effect sizes. The observed changes were generally of similar magnitude for male and female cadets, and similar among the three academies. Conclusions: Anthropometrics and physical fitness were relatively stable in Norwegian male and female army, navy, and air force cadets during 3 years of military academy education. Observed changes were typically classified as trivial or small. The initial gap in physical fitness between male and female cadets did not narrow during the education years. Norwegian male and female cadets displayed relatively good physical fitness profiles, compared to sex-matched cadets and soldiers from previously studied military populations