The purpose of this study is to assess the efficacy of dynamic tape in prevent shoulder muscle fatigue.

After being informed about the study and the potential of risk, all participants will undergo a screening to determine eligibility for study entry and giving written informed consent.

We will include 20 participants who have pitch 100 times with dynamic taping or shame taping in randomized sequence. There must be more than 2 weeks resting between 2 test. We will test maximal force in shoulder flexion, extension, abduction and adduction before and after test. We also record spins and speed of baseball for performance outcome.

To our hypothesis, we suggest dynamic taping could decrease the arm fatigue after long-term pitching.

Inclusion Criteria:

• more than 20 years old
• amateur baseball player
• could tolerate pitching 100 times

Exclusion Criteria:

• shoulder pain who could not tolerate 100 pitching
• upper limb surgery history
• Allergy to topical agent