Abstract
Sports have high risks of knee injury whether to elite or recreational participants. Proprioception and muscle strength might be factors that reduce knee injuries risk. Elite athletes showed enhanced proprioceptive acuity and isometric muscle strength in knee rotation compared to non-athletes. Whether recreational soccer participation, likewise, enhances knee rotatory proprioception and isometric muscles strength is not yet studied. The primary purpose of this study was to check whether recreational soccer participation would influence knee rotatory proprioceptive acuity and knee rotators isometric muscles strength compared to healthy sports non-participants. Secondly, was to check whether knee rotators isometric muscles strength correlate to knee rotatory proprioceptive acuity. This cross sectional study was conducted on thirty healthy male volunteers, 15 recreational soccer participants (RSP) and 15 matched not participating in sports (controls). Evaluating knee rotation proprioceptive acuity were carried out using active movements' discrimination tasks. Knee rotators isometric muscles strength was assessed using hand held dynamometer. Unpaired T-test was used to compare groups' means for proprioceptive acuity and isometric muscles strength. Paired T-test was used to compare within groups means differences between internal and external rotations knee proprioception and isometric muscles strength. Pearson correlation coefficient was used to correlate external and internal rotation proprioceptive acuity and isometric muscles strength of knee external and internal rotators respectively in both groups. Proprioceptive acuity was enhanced in internal rotation in RSP group compared to controls (P = 0.031). Isometric muscles strength showed higher values in RSP compared to control group in external (P = 0.023) and internal ( P= 0.041) rotation respectively. Within groups' isometric muscles strength of external rotation were higher than internal rotation in RSP (0.002) and control groups (0.001) respectively. No significant correlations were reported between proprioceptive acuity and isometric muscles strength for either directions of movement or groups. Recreational soccer players showed enhanced knee proprioception in knee internal rotation, and isometric muscles strength of knee external and internal rotators compared to controls. These enhancements might serve to protect against knee injuries, especially those injuries with rotation mechanisms such as anterior cruciate ligament and meniscus injuries.