Impact of a 15-week ability-based training program on body composition and physical fitness in university-based fire academy recruits

Background Firefighters must be prepared to perform strenuous tasks in extreme environments (i.e. elevated heat and humidity, natural disasters, etc.). One of the main purposes of a fire academy is to prepare recruits for the rigors of this profession. This study aimed to determine the impact of a 15-week ability-based physical training (PT) program on body composition and physical performance among university fire academy recruits.Methods Thirty-two (n = 32; male = 29 and female = 3) fire academy recruits (age = 21.22 ± 3.17 yrs; height (HT) = 179.17 ± 7.85 cm; body mass (BM) = 76.55 ± 16.12 kg; body fat percentage (BF%) = 17.14 ± 8.77%) voluntarily agreed to participate in a physical assessment battery at the commencement and at two additional time points during their academy training. In addition to HT, which was measured using a stadiometer, BM, BF%, and skeletal muscle mass (sKM) data were collected using bioelectrical impedance (InBody 270). Physical performance tests included the countermovement jump (CMJ), isometric mid-thigh pull (IMTP), pull-ups, cadenced push-ups (80 bpm), and a 1.5-mile run. Follow-up testing occurred at weeks 7 and 15. In the interim, students participated in an ability-based physical training (PT) program, including sandbag and bodyweight training and a running program based on time-based finish classifications. A series of repeated measures ANCOVA, with participant sex as a covariate, were utilized to determine the impact of the training program on the measured variables. Normality was confirmed while sphericity was violated. Therefore, Greenhouse-Geisser corrections were applied. No multivariate outliers were detected in the model; significance was set at p < 0.05.Results Significant improvements (p ≤ 0.001) in sKM and BF% were observed between testing sessions 1 and 2, with statistically insignificant improvements between testing sessions 2 and 3, suggesting the overall program was impactful in providing positive body composition changes. Regarding performance, average 1.5-mile run times significantly improved over baseline during subsequent testing sessions, indicating improved cardiovascular fitness with running a maximum of 2 days/wk. No other significant improvements in performance were observed.Conclusions Large group ability-based training in firefighter recruits yielded significant improvements in body composition, including increases in sKM and decreases in BF%, as well as significant improvement in 1.5-mile run times. Interestingly, no significant changes were observed in CMJ, IMTP, pull-ups, or push-ups, indicating that accumulated fatigue and inability to consistently apply progressive overload may have affected fitness testing performance.