Patellar tendinopathy (PT) is the common cause of anterior knee pain, particularly in sports required repeated jumping and landing, such as volleyball. PT clinically presents as anterior knee pain and localized tenderness at the patellar tendon. To evaluate the severity of symptoms of PT, the VISA-P questionnaire is a self-administered, well-validated, and widespread assessment tool. In the long term, athletes would land with knee avoidance patterns and transfer the load to the hip joint caused further hip-related injury. Lower extremities eccentric exercise has been proven the most beneficial treatment of PT. However, the course lasts for three to six months. For athletes who are still in season, it's difficult to get the immediate effect. A newly developed biomechanical taping, dynamic tape, considered to be beneficial for load absorption during muscle eccentric contraction during landing and further normalized the lower extremities load contribution by its viscoelasticity property. However, no past research has confirmed this effect.

Therefore, the aims of the study are to translate the English VISA-P questionnaire to the Chinese and to study the reliability and validity of the Chinese version. In the next part, the investigators investigate the different landing biomechanics between individuals with and without patellar tendinopathy and establish the reliability of different landing tasks, and further explore whether the dynamic tape alters landing biomechanics in volleyball players.

Patellar tendinopathy is one of the most common causes of anterior knee pain, particularly common in sports that required repeated jumping and landing, such as volleyball and basketball. Patellar tendinopathy clinically presents as anterior knee pain and localized tenderness at the patellar tendon. To evaluate the severity of symptoms of patellar tendinopathy, the VISA-P (Victorian institution of sports assessment- patellar tendon) questionnaire is an easily self-administered, well-validated assessment tool and commonly used across several countries. In the long term, athletes would land with knee avoidance landing patterns and transfer the load to the hip joint, which caused the further hip-related injury. Lower extremities eccentric contraction exercise has been proven the most beneficial treatment of patellar tendinopathy. However, the course of treatment needs to last for three to six months. For athletes who are still in season, it's difficult to get the immediate effect. A newly developed biomechanical taping, dynamic tape, considered to be beneficial for load absorption during muscle eccentric contraction during landing and further normalized the lower extremities load contribution by its viscoelasticity property. However, no past research has confirmed this effect.

Therefore, the aims of this study are to translate the English VISA-P questionnaire to Chinese and to study the reliability and validity of the Chinese version of the VISA-P. In the next part of the study, the investigators investigate the different landing biomechanics between individuals with and without patellar tendinopathy and establish the reliability of different landing tasks, and further explore whether the dynamic tape alters landing biomechanics in volleyball players. Methods: The first part of the study will include 15 subjects with the symptoms of patellar tendinopathy and 15 healthy subjects to fill out the translated questionnaire. In the second part of the study will include 15 volleyball players with the symptoms of patellar tendinopathy and 15 healthy controls. To compare the landing biomechanics between two groups, all subjects will conduct three landing tasks and the kinematics and kinetics of lower extremities、loading rate of vertical ground force and patellar tendon force will be recorded. In the third part of the study, the investigators will recruit 50 volleyball players with the symptoms of patellar tendinopathy and randomly assign to two groups, the dynamic tape, and sham tape. After taping, subjects will conduct three landing tasks, and the landing biomechanics will be recorded. Statistical analysis: Intra-class correlation, Pearson's correlation, and Mann-Whitney test will be used to analyze the test-retest reliability, concurrent validity, and construct validity of the Chinese version VISA-P. Repeated measures MANOVA will be used to analyze the interaction of landing biomechanics in three landing tasks between patellar tendinopathy group and healthy control, and further, analyze the interaction in three landing tasks between the dynamic tape and sham tape group in landing biomechanics parameters. Alpha level= 0.05

Inclusion Criteria:

1. at the age of 16 to 35 years old
2. volleyball players joined the school team or professional level
3. over 90 minutes of training time per week -

Exclusion Criteria:

1. unbearable pain occurred at the patellar tendon when conducting landing tasks
2. there are currently other acute injuries to the lower extremity
3. lower extremity has undergone surgery or fracture in the past
4. with a history of rheumatoid arthritis, systematic and neurological diseases -