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Background and objectives: Respiratory muscle fatigue is one of the important factors limiting sports performance due to the metaboreflex. This reflex will cause a decrease in blood flow to the extremities and accelerate exercising limb fatigue. Previous studies found that inspiratory muscle training (IMT) can effectively enhance the respiratory muscle endurance and reduce fatigue during long-duration exercise or aerobic exercise, thereby enhancing athletic performance. However, the mechanism between inspiratory muscle strength, change of limb blood flow and sports performance still requires investigation, especially in short-duration exercise, anaerobic or both aerobic and anaerobic exercise. The purpose of this study was to investigate the effects of 4-week inspiratory muscle training on respiratory muscle strength, limb blood flow change rate and sports performance in recreational 800-m college runners. Materials and Methods: Twenty healthy 800-m college runners randomized into the IMT group (11 subjects) and control group (9 subjects). IMT consisted of 30 inspiratory efforts twice daily, 5 days a week, with intensity at 50%, 60%, 70% and 80% of maximum inspiratory pressure (MIP) for 4 weeks, while a control group kept 50% of MIP for 4 weeks. An 800-m trial test, limb blood flow change rate by using Impedance Plethysmography, and MIP were as the outcome measured variables and be evaluated. All measured variables were assessed before and after 4-week IMT training. Two-way ANOVA was conducted for statistical analysis. Results: The results showed significantly interaction between groups and pre-posttest. IMT group significantly decreased limb blood flow change rate from 19.91 ± 11.65% to 9.63 ± 7.62% after received the IMT training program (p < 0.05). The MIP significantly improved from 112.95 ± 27.13 cmH2O to 131.09 ± 28.20 cm H2O in IMT group, and the 800-m trial test also shorted the running time from 162.97 ± 24.96 s to 156.75 ± 20.73 s. But the control group no significantly changed in MIP and 800-m trial test. Conclusions: Our results indicated that the 4-week IMT training (twice a day, 5 days a week) significantly improves participants’ inspiratory muscle strength, 800-m running performance and decreases the limb blood flow change rate.

Background and Objectives: Sleeper stretching (SS) can improve the shoulder’s range of motion (ROM) for pitchers with glenohumeral internal rotation deficit (GIRD). However, no evidence has proven the effect of Kinesio taping (KT) on shoulder strength and ROM. Therefore, this study compared the effects of SS and KT on shoulder rotation ROM, muscle strength, and sub-acromial distance in pitchers with GIRD. Materials and Methods: Thirty-one pitchers with GIRD were allocated into control, KT, and SS groups. Shoulder rotation ROM, muscle strength, and sub-acromial space were measured before and after treatment with SS or KT. Results: The results revealed that KT and SS significantly enhanced shoulder rotation ROM in pitchers with GIRD. External rotator strength significantly increased following KT but significantly decreased after SS. KT and SS exerted no effects on the sub-acromial space. Conclusions: KT and SS improve shoulder rotation ROM in pitchers with GIRD. In addition, KT improves shoulder external rotator strength, and SS reduces it.