Effects of 8-week Nonlinear Periodized Training Program on Physical Fitness and Contributors of Functional Knee Joint Stability in 101st Division Army Soldiers

Army soldiers engage in various types of vigorous physical fitness training daily and unintentional musculoskeletal injuries are quite common. Based on previous research, training principles, and theories, a training program was developed to target components of physical fitness and improve neuromuscular and biomechanical factors that are important to knee joint stability. The purpose of this study was to evaluate the effects of an 8-week nonlinear periodized training program on physical fitness and contributors of functional knee joint stability in 101st Division Army soldiers.Due to the timing of the study, the duration of this training overlapped with the soldiers' deployment preparation schedule. As a result, of 52 soldiers who were initially enrolled (28 in the experimental group and 24 in the control group), only 26 soldiers completed the study (23 in the experimental group and 13 in the control group). Knee and hip strength, knee joint rate of force development, knee proprioception, and knee and hip neuromuscular and biomechanical characteristics during a stop-jump and a drop-jump task were measured before and after the intervention.There were no statistically significant findings for any dependent variables. High attrition rate and the lack of training exposure were the confounding factors for this study. Future studies must consider soldiers' training/deployment schedules to avoid those confounding factors and should monitor the daily training exposure and types of training for the control group