proprioception consists of a combination of joint position sense , i.e. , the ability to 
 detect the movement and position of a limb in space1 , and the sense of muscular effort and tension2 . the joint position sense is a very important contributor to 
 joint coordination , maintenance of muscle stiffness , and the production of natural movements 
 for appropriate task performance . muscle fatigue is an exercise - induced decline in the ability of muscles to produce force or 
 power4 and is known to alter 
 proprioception5 . previous studies have 
 shown that muscle fatigue negatively affects the joint position sense during both passive 
 and active examination tests6 . decline in 
 knee proprioception as a result of physical fatigue may be a risk factor for knee ligament 
 injuries7 . in sports games , most of the 
 injuries occur near the end of the game because of the fatigued state of the players8 . the use of kinesiology taping is gradually increasing in sports competitions , such as the 
 olympic games or european football leagues , as well in sports medicine9 . previous studies have shown the effects of kinesiology 
 taping on pain control10 , 11 , joint support12 , 
 13 , and muscle function14 , 15 . therefore , the aim of this study was to determine whether 
 kinesiology taping decreases the repositioning error of the knee joint after quadriceps 
 fatigue and ultimately confirm if kinesiology taping can improve joint position sense . fifteen male subjects ( mean  sd : age , 21.87  0.83  years ; height , 1.75  5.05 m ; body 
 weight , 66.33  9.81  kg ) and fifteen female subjects ( mean  sd : age , 21.47  0.52  years ; 
 height , 1.61  5.07 m ; body weight , 54.33  7.21  kg ) volunteered for this study . subjects 
 were excluded if they had any known musculoskeletal disorders of the lower limb , 
 neurological problems , or balance disturbances within the 6 months prior to the start of the 
 study . before participation , subjects provided written informed consent , which was approved 
 by the human ethics committee of kyung sung university . three reflective markers were attached to the skin of the greater trochanter , the lateral 
 epicondyle of the femur , and the lateral malleolus using double - sided tape . for measurements 
 of knee range of motion , the axis of a digital goniometer ( digital 
 absolute+axis goniometer ; fabrication enterprises inc . , white plains , ny , 
 usa ) was placed on the lateral epicondyle of the femur , with the stationary arm along the 
 midline of the femur and the moveable arm at the midline of the lateral malleolus16 . before starting the formal experiment , a 
 physical therapist with more than 10  years of experience practiced taking measurements using 
 a digital goniometer for 1 day in order to reduce measurement error . prior to practical testing , participants were given instructions on fatigue - induced 
 exercise , and the examiner with more than 10  years of experience demonstrated the 
 fatigue - induced exercise procedure . an 
 assistant set a metronome at 20 beats per minute ( bpm ) , and the participant assumed a 
 squatting position on the floor with the feet shoulder - width apart . the assistant gave a 
  start  command , and the participant then performed squats ( sitting as low as possible 
 without lifting the heels and then returning to the standing position in time with the 
 metronome ) while the assistant counted . three sets of 10 squats were performed with 30 
 seconds of rest between sets . kinesiology tape ( bb tape , wetape inc , seoul , korea ) was applied by a physical therapist 
 specialized in kinesiology taping methods . before kinesiology taping the kinesiology tape was applied with approximately 3040% stretch on the 
 3 quadriceps muscles . for the rectus femoris muscle , the kinesiology tape was applied from 
 the anterior inferior iliac spine to the superior border of the patella while holding the 
 knee in full flexion ( fig . 1 . application of kinesiology tape on the ( a ) rectus femoris muscle , ( b ) vastus 
 medialis muscle , and ( c ) vastus lateralis muscle and ( d ) taping for superior elevation 
 of the patella . ) . for the vastus medialis muscle , the kinesiology tape was applied from the lower 
 part of the intertrochanteric line ( the medial lip of the linea aspera of the femur ) to the 
 medial superior aspect of the patella ( fig . 1b ) 
 while holding the knee in full flexion . for the vastus lateralis muscle , the kinesiology 
 tape was applied from the greater trochanter of the femur to the lateral superior aspect of 
 the patella ( fig . 1c ) while holding the knee in 
 full flexion . to enable superior gliding of the patella , kinesiology tape with a width of 
 2.5  cm was applied from the inferior pole of the patella in the direction of the vastus 
 medialis and vastus lateralis ( i.e. , stretch of 4050% in the middle of tape , with no 
 stretch at the ends of the tape ) , while holding the knee at approximately 5060 of flexion 
 ( fig . application of kinesiology tape on the ( a ) rectus femoris muscle , ( b ) vastus 
 medialis muscle , and ( c ) vastus lateralis muscle and ( d ) taping for superior elevation 
 of the patella . the examiner randomly performed passive 
 knee extension of the dominant leg from a starting position ( knee 90 flexion ) to a target 
 angle ( 30 , 45 , or 60 ) determined using a digital goniometer . after holding the target 
 position for 3 seconds , the examiner placed the limb in the starting position17 . the subjects were then instructed to 
 actively reproduce the same angle that was passively performed by the examiner17 . the repositioning error of the knee joint 
 was recorded using a digital goniometer for only 1 trial , along with random selection of the 
 target angle , to minimize learning effects . subsequently , the repositioning error of the 
 knee joint was remeasured immediately after completion of the quadriceps muscle fatigue 
 protocol and also immediately after application of kinesiology tape to the quadriceps and 
 patella without rest after the measurement obtained following muscle fatigue . repeated one - way anova was used to analyze changes in repositioning error of the knee 
 joint . the results for the knee joint repositioning error of the dominant leg are presented in 
 table 1table 1.comparison of the knee joint repositioning error before and after quadriceps 
 fatigue and with kinesiology taping after quadriceps fatiguevariablemean  sd ( )pre - fatiguepost - fatiguewith tapingrepositioning error3.41  1.424.25  1.67 * 2.99  1.24 * significant difference ( p<0.05 ) between before and after quadriceps fatigue . significant difference ( p<0.05 ) between quadriceps fatigue and kinesiology taping 
 after quadriceps fatigue .. repositioning error of the knee joint significantly increased after 
 quadriceps fatigue compared with before quadriceps fatigue ( p < 0.05 ) . however , compared 
 with the knee joint repositioning error obtained after quadriceps fatigue , the knee joint 
 repositioning error obtained after use of kinesiology taping following quadriceps fatigue 
 was significantly lower ( p < 0.05 ) . * significant difference ( p<0.05 ) between quadriceps fatigue and kinesiology taping 
 after quadriceps fatigue . , local muscular fatigue causes negative 
 effects on joint proprioception18 by 
 increasing the threshold of muscle spindle discharge , disrupting afferent feedback , and 
 consequently altering conscious knee joint awareness19 . in line with previous work7 , 
 20 , the current study shows an impaired 
 sense of knee joint position under fatigued conditions . we found that the application of 
 kinesiology tape decreases fatigue - induced repositioning errors . when kinesiology tape is applied with an elasticity of 3040% , the 
 skin is stretched / deformed by joint movement22 . therefore , the application of kinesiology tape may have decreased 
 the repositioning error by increasing knee joint proprioception through this stimulation of 
 cutaneous mechanoreceptors23 , 25 . fatigue protocols would presumably have more effect on muscle than joint tissue because a 
 decreased joint position sense is thought to be secondary to a decrease in muscle receptor 
 input26 . although the evidence 
 regarding muscle activity is inconsistent23 , 27 , recent studies have shown that 
 kinesiology tape application enhances muscle function14 , 15 . the application of 
 kinesiology tape on the rectus femoris , vastus medialis , and vastus lateralis , such as in 
 the current study , increases eccentric muscle strength in healthy subjects28 . therefore , application of kinesiology 
 tape to the quadriceps muscles may assist the reduced knee extension function caused by 
 muscle fatigue . in addition , kinesiology taping that elevates the patella , applied with 
 4050% tension , may provide external support and assist the function of quadriceps muscles 
 by enhancing the superior glide of the patella29 throughout various angles of knee extension . however , the mechanism 
 underlying the effects of kinesiology taping on fatigue - induced muscle is beyond the scope 
 of this study , and further study is needed . first , the compensation of the pelvis and trunk during 
 assessment of knee joint angle was not controlled . third , we did not evaluate the duration of the effect of 
 kinesiology taping on knee repositioning errors after muscle fatigue . fourth , the learning 
 effect was not completely eliminated because the repositioning error after kinesiology 
 taping was assessed last . further studies 
 are required to resolve the limitations of the current study and ascertain the effects of 
 kinesiology taping on muscle fatigue , which was not determined experimentally in this 
 study .
[ purpose ] the purpose of this study was to identify the effects of kinesiology taping on 
 repositioning error of the knee joint after quadriceps muscle fatigue . 
 [ subjects ] thirty 
 healthy adults with no orthopaedic or neurological problems participated in this study . 
 [ methods ] 
 the repositioning error of the knee joint was measured using a digital 
 goniometer when the subjects extended their dominant - side knee to a random target angle 
 ( 30 , 45 , or 60 ) with their eyes closed , before and after a quadriceps muscle fatigue 
 protocol , and after application of kinesiology tape . 
 [ results ] we found that repositioning 
 errors of the dominant - side knee joint increased after quadriceps fatigue compared with 
 no - fatigue conditions . however , kinesiology taping of the quadriceps muscle and patella 
 after quadriceps fatigue significantly decreased repositioning errors of the knee joint . 
 [ conclusion ] these results suggest that quadriceps fatigue increases the repositioning 
 error of the knee joint , whereas application of kinesiology tape decreases fatigue - induced 
 joint repositioning error .