Background: Recruit training injuries have caused serious problems for troop training and medical support. The lower limbs is the site where recruit injuries occur the most. Bio-impedance (BIA) measures body composition quickly and accurately. Our aim was to identify the risk factors for lower limbs training injuries to recruits due to body composition.
Methods: A total of 282 recruits were included. Before training, use BodyStat QuadScan 4000 multifrequency BIA system to measure the body composition of recruits. After training, they were divided into two groups according to the occurrence of lower limb training injuries. The basic characteristics of the two recruits were compared by Wilcoxon rank sum test. Receiver operator characteristic (ROC) curves was performed on the indicators with statistical difference between the two groups to find the cutoff point. Finally, multivariate logistic regression analysis was used to find the risk factors of lower limb training injuries.
Results: Compared with the lower limb uninjured group, the lean mass percentage (P = 0.003), TBW percentage (P = 0.010), extracellular water (ECW) percentage (P = 0.023), intracellular water(ICW) percentage (P = 0.027), 3rd space water (P = 0.021) and basal metabolic rate(BMR)/total weight (P = 0.014) of the lower limb injury group was higher. On the contrary, the body fat percentage (P = 0.003) and body fat mass index (BFMI) (P = 0.005) of the lower limb injury group was lower. The results of multivariate logistic regression analysis showed that TBW percentage > 65.350% (P = 0.050, OR=2.085) and 3rd space water >0.950 (P = 0.045, OR=2.342) were independent risk factors for lower limb injuries.
Conclusions: TBW percentage> 65.35% and 3rd space water >0.950 were independent risk of lower limb training injuries. These recruits need to be paid more attention during training.