Background: Patellofemoral pain syndrome (PFPS) is the most prevalent disease of the knee. The purpose of this study was to compare the acute effects of various warm-up methods on several performance measures and pain intensity in athletes with and without PFPS.
 Methods: This clinical trial study included 18 to 24-year-old professional female athletes with or without PFPS. Both groups performed warm-up protocols, including general stretching, foam rolling, and Federation Internationale de Football Association (FIFA) 11+ warm-up exercises in three test sessions simultaneously. The data collection procedure was implemented on three separate days in one week. Pain intensity was measured using the Visual Analogue Scale (VAS). Countermovement jump (CMJ) and squat jump (SJ) to measure the stretch-shortening cycle (SSC) and Landing Error Scoring System (LESS) were examined before and after each session.
 Results: No significant difference was observed between the effect of different warm-ups in groups with and without PFPS regarding the use of the SSC (P = 0.185), while there were significant differences in the effect of various warm-up protocols on LESS (P < 0.001) and pain scores (P < 0.001).
 Conclusion: Using the foam roller as a warm-up method can decrease the pain intensity in athletes with PFPS but may increase their LESS score. In addition, there was no difference in the effect of various warm-up methods on the SSC between athletes with and without PFPS. Finally, it seems that foam rolling should be used with more caution as a part of warming up in athletes with PFPS.