Does Adding Power Exercises to Muscle Force Training Result in Superior Benefits for Patellofemoral Pain People? Randomized and Controlled Clinical Trial

Patellofemoral pain (PFP) is one of the most common forms of knee pain and has a negative impact on the level of physical activity and quality of life of patients. Although strengthening of the hip and knee muscles has good clinical effects in the treatment of PFP, most exercise protocols do not follow the American College of Sports Medicine (ACSM) guidelines and are not clearly described, making it difficult to apply them in practice clinical and research. In addition, recent studies have shown that these patients also have a power deficit of these muscles. However, it is not known whether the addition of power exercises to a muscle strengthening program would result in superior benefits, especially in relation to pain and physical function. Therefore, the objective of this study is to verify if the improvement in pain intensity, physical function, kinesiophobia, self perception of improvement, quality of life and muscle function variables after a training program of strength and muscular power is superior to that observed in an isolated muscle strength training. This study will be randomized and controlled, developed with individuals with DPF, allocated in one of two groups: Strength Training Group (STG) and Strength and Power Training Group (SPTG). The primary outcomes will be intensity of pain and physical function, while the secondary outcomes will be kinesiophobia; self perception of improvement; quality of life; the peak of isometric abductor and hip extensor torque, and knee extensor; and the rate of development of torque of the abductors and extensors of hip, and extensors of knee at 30% and 90% of maximum isometric torque. Participants in both groups will be evaluated before the intervention (pre), after the end of the intervention (post) and three, six and twelve months after the intervention. Data analysis will follow the intention-to-treat principle. To compare the groups at different times (pre, post and after three, six and twelve months of the intervention) will be used two-way analysis of variance (GROUP X MOMENT) with mixed model, with Bonferroni post hoc to identify specific differences. The significance level will be 0.05.