Body Composition and Fitness in Structural Firefighters: Differences According to Injury Status and Anatomical Location

The job demands of firefighting often place the firefighter at risk of injury. However, firefighters may often continue working with an existing injury. How existing injuries could affect job performance may be extrapolated from fitness test performance. PURPOSE: To analyze differences in body composition and fitness between currently injured (self-reported) and uninjured structural firefighters. METHODS: Retrospective analysis was conducted on data collected from 270 firefighters (258 men, 12 women) as part of a health and wellness program within one fire department. Firefighters voluntarily participated within the program. Body composition metrics included: height; body mass; body mass index (BMI); body fat percentage (BF%); fat mass (FM); lean body mass; and waist:hip ratio. Fitness data included: flexibility measured using novel equipment (trunk flexion, left rotation, right rotation, trunk extension, shoulder flexion, left lateral flexion, right lateral flexion); grip strength; absolute and relative predicted
one-repetition maximum (1RM) leg press; 90-second crunches; 120-second push-ups; and estimated maximal aerobic capacity (V̇O2max). Firefighters self-reported if they were, or were not, injured. Number of current injuries, and their anatomical location, were used to place them in groups: uninjured (UNINJ; n=208); upper-body injury (UBI; n=11); lower-body injury (LBI; n=19); back injury (BI; n=12); and more than one (multiple) injuries (MULT; n=20). A series of univariate ANOVAS, with sex and age as covariates, compared the groups in body composition and fitness (p<0.05) with a post hoc Bonferroni adjustment for multiple comparisons. RESULTS: The MULT group was older (p=0.005), heavier (p=0.001), and had a greater BMI (p=0.006) than the UNINJ group, and greater BF% (p≤0.039) and FM (p≤0.025) than the UNI and LBI groups. The BI group had poorer trunk extension compared to the UBI, LBI, and MULT groups (p≤0.033), poorer left lateral flexion compared to the UNINJ and MULT groups (p≤0.039), and performed fewer crunches than the UNINJ group (p=0.004). The LBI, BI, and MULT groups had a lower absolute and relative 1RM leg press compared to the UNINJ
group (p≤0.026). The LBI and MULT groups had a lower V̇O2max compared to the UNINJ group (p≤0.007). CONCLUSIONS: The data indicated the presence of injuries can impact select fitness test performance in firefighters. Firefighters with more than one injury tended to have poorer body
composition, and lesser strength and V̇O2max. The BI group was limited with trunk extension and flexion actions. The LBI group had lower-body strength limitations. Poorer fitness test performance due to an injury could indicate limitations in job tasks that require certain qualities (e.g., firefighters in the LBI, BI, and MULT groups may struggle with maximal lifting tasks). Firefighters with an injury may also reduce any exercise they do, which could have a downstream effect of poorer body composition and fitness and increase their risk of future injury. PRACTICAL APPLICATIONS: Although poorer performance in the fitness tests could be the result of the current injury, these data highlight certain qualities that could be developed to prevent specific injuries in firefighters. It should be noted that all firefighters from the program were still working. Training staff should assist firefighters with current injuries to complete adapted exercise programs so that negative impacts to job performance are reduced.