The Effect of Two PNF Stretching Programs and Lower Limb Strengthening on Pain ‎and Proprioception of the Knee Joint before and after Local Fatigue of the Quadriceps ‎Muscle in Male Athletes with Patellofemoral Pain Syndrome‏ ‏

Fatigue of the quadriceps muscle causes pain and decreased knee proprioception. The aim of research was the effect of two PNF stretching programs and lower limb strengthening on pain and knee proprioceptive of the knee joint before and after local fatigue of the quadriceps muscle in male athlete with patellofemoral pain.

This research was semi-experimental and pre & post-test. The statistical population included men aged 20-30 with patella pain in Tehran. 24 people were placed in two groups of PNF stretching exercises (12 people) and strengthening (12 people) in a targeted and random selection. All subjects signed a personal consent form before participating in the study. Each group did their exercises for eight weeks and three 60-minute sessions each week. Before & after the exercises (before and after the test), knee pain and proprioceptive sensation were measured using visual pain measurement (VAS) and biodex isokinetic (model IV Pro made USA), respectively. Data were analysis significant (P<05/0) using the combined repeated measure.

the comparison of the first and third tests (before fatigue) (ES=0.5, p<0.05 and        F (1,22) =4.417) . The comparison of the second & fourth tests after fatigue(ES=0.8, p<0.05 and F (1,22) =148.4), there was a significant difference (ES=0.4, p<0.002 and F (1,22) =52.14). Pain reduction after training was 29% in the stretching group 18% in the strengthening group. The net effect of training on depth sensation improvement was significant (ES=0.6, p<0.005 and F (1,22) =2.404). Regarding the comparison of the first & third test (before fatigue) (ES=0.6, p<0.001 and F (1,22) =108.2). The comparison of the second & fourth test (after fatigue), there was a significant difference (ES=0.5, p<0.002 and F (1,22) =51.1). The improvement in proprioception after training was 15% in the stretching and 11% in the strengthening group. The exercises in the PNF stretching group were more effective on both variables in the post-test and after the training period.

Both exercise programs have been concluded for pain factor and proprioception, but the effect of PNF training to reduce pain and improve proprioception of patients was the amount of consumption.