Caffeine supplementation improves the cognitive abilities and shooting performance of elite e-sports players: a crossover trial.

We explored the effect of 3 mg/kg of caffeine supplementation on the cognitive ability and shooting performance of elite e-sports players. Nine e-sports players who had received professional training in e-sports and had won at least eighth place in national-level e-sports shooting competitions. After performing three to five familiarization tests, we employed a single blind, randomized crossover design to divide participants into caffeine trial (CAF) and placebo trial (PL). The CAF trial took capsules with 3 mg/kg of caffeine, whereas the PL trial took a placebo capsule. After a one-hour rest, the Stroop task, the visual search ability test, and the shooting ability test were conducted. The CAF trial's performance in the Stroop task in terms of congruent condition (P = 0.023) and visual search reaction time with 20 items (P = 0.004) was significantly superior to those of the PL trial. In the shooting test, the CAF trial's kill ratio (P = 0.020) and hit accuracy (P = 0.008) were significantly higher, and the average time to target (P = 0.001) was significantly shorter than those of the PL trial. Caffeine supplementation significantly improves e-sports players' reaction times and shooting performance.

Carbohydrate mouth rinsing decreases fatigue index of taekwondo frequency speed of kick test.

Carbohydrate mouth rinsing (CMR) potentially affects the interval training performance of taekwondo athletes. This study explored the effect of CMR on vertical jump, kicking speed, and fatigue index before and after simulated taekwondo competition. In a crossover experimental design, 13 trained taekwondo athletes were randomly divided into the CMR and control trials. After warming up, the participants used 6.6% maltodextrin (CMR trial) or mineral water (control trial) to rinse their mouth. Next, the participants underwent tests of vertical jump, kicking speed, and maximum number of kicks. After the tests, the participants rinsed their mouth again, followed by using Wingate testing bikes for 5-s sprint and 25-s rest to simulate taekwondo competitions. Four repetitions were performed in each round for 2 min for a total of three rounds. The results revealed that the fatigue index of the participants in the CMR trial before and after the simulated competition was significantly lower than that of the control trial. However, the two trials differed nonsignificantly in their performance in vertical jump, kicking speed, and the simulated competition. Overall, the study results indicated that CMR reduces the fatigue index but no change was observed in performance for vertical jump, kicking speed, and the simulated competition of trained taekwondo athletes.

Immediate Effects of Acupuncture on Explosive Force Production and Stiffness in Male Knee Joint.

Acupuncture can improve explosive force production and affect joint stiffness by affecting muscle activation levels. This study aims to explore the effects of true acupuncture (TA) compared with sham acupuncture (SA) on the explosive force production and stiffness of the knee joint in healthy male subjects. Twenty subjects were randomly divided into the TA group (n = 10) and SA group (n = 10) to complete isokinetic movement of the right knee joint at a speed of 240°/s before and after acupuncture. Futu (ST32), Liangqiu (ST34), Zusanli (ST36), Xuehai (SP10), and Chengshan (BL57) were selected for acupuncture. The intervention of SA is that needles with a blunt tip were pushed against the skin, giving an illusion of insertion. The results showed that acupuncture and the intervention time had a significant interaction effect on knee joint explosive force and joint stiffness (p < 0.05). The average maximum (max) torque, average work, average power, average peak power and total work of the TA group increased significantly after acupuncture (p < 0.05), while the SA group did not (p > 0.05). Therefore, true acupuncture can immediately improve the explosive force and joint stiffness of the male knee joint by inducing post-activation potentiation (PAP) and/or De-Qi.

Effect of Acupuncture on Timeliness of Male Shoulder Joint Endurance.

Acupuncture as a traditional and commonly used treatment has been used to improve the performance of athletes. In the improvement of female shoulder joint explosive force and muscle endurance also has an immediate effect. However, whether the effect of acupuncture therapy can be maintained after improving athletic performance still worth further discussion. The purpose of this study was to explore the timeless of the physical neurophysiological response induced by acupuncture at specific acupoints in improving endurance performance. Seventeen healthy male participants completed six groups of shoulder joint isokinetic exercises. The isokinetic exercise completed in the first group was taken as the baseline. After acupuncture for 15 min, the following 5 isokinetic experiments were completed. Acupuncture acupoints included Binao (LI14), Jianliao (SJ14), Naohui (SJ13), Zhongfu (LU1), Xiabai (LU4), Tianfu (LU3) and Xiaoluo (SJ12). The results show that acupuncture can improve physical performance for 10-20 min. After acupuncture, the maximum torque, average power, average work and total work values significantly increased (p < 0.05). Stimulation of acupoints can effectively improve the performance of periarticular muscle endurance around the shoulder, but this improvement is limited by time.

Acute Effects of Kinesiology Taping Stretch Tensions on Soleus and Gastrocnemius H-Reflex Modulations.

This study examined the acute effects of stretch tensions of kinesiology taping (KT) on the soleus (SOL), medial (MG), and lateral (LG) gastrocnemius Hoffmann-reflex (H-reflex) modulation in physically active healthy adults. A cross-over within-subject design was used in this study. Twelve physically active collegiate students voluntarily participated in the study (age = 21.3 ± 1.2 years; height = 175.6 ± 7.1 cm; body weight = 69.9 ± 7.1 kg). A standard Y-shape of KT technique was applied to the calf muscles. The KT was controlled in three tension intensities in a randomised order: paper-off, 50%, and 100% of maximal stretch tension of the tape. The peak-to-peak amplitude of maximal M-wave (Mmax) and H-reflex (Hmax) responses in the SOL, MG, and LG muscles were assessed before taping (pre-taping), taping, and after taping (post-taping) phases in the lying prone position. The results demonstrated significantly larger LG Hmax responses in the pre-taping condition than those in the post-taping condition during paper-off KT (p = 0.002). Moreover, the ΔHmax/Mmax of pre- and post-taping in the SOL muscle was significantly larger during 50%KT tension than that of paper-off (p = 0.046). In conclusion, the stretch tension of KT contributes minor influence on the spinal motoneuron excitability in the triceps surae during rest.

Acute effects of kinesiology tape tension on soleus muscle h-reflex modulations during lying and standing postures.

Kinesiology tape (KT) has been widely used in the areas of sports and rehabilitation. However, there is no gold standard for the tape tension used during a KT application. The purpose of this study was to examine the effects of KT application with different tension intensities on soleus muscle Hoffmann-reflex (H-reflex) modulation during lying and standing postures. Fifteen healthy university students were tested with 3 tape tension intensities during separate visits with a randomized sequence: tape-on no tension (0KT), moderate (about 50% of the maximal tape tension: (ModKT), and maximal tape tension (MaxKT). During each experimental visit, the H-reflex measurements on the soleus muscle were taken before, during, and after the KT application for both lying and standing postures. The H-wave and M-wave recruitment curves were generated using surface electromyography (EMG). There was a main effect for posture (p = 0.001) for the maximal peak-to-peak amplitude of the H-wave and M-wave (Hmax/Mmax) ratio, showing the depressed Hmax/Mmax ratio during standing, when compared to the lying posture. Even though the tension factor had a large effect (ηp2 = 0.165), different tape tensions showed no significant differential effects for the Hmax/Mmax ratio. The spinal motoneuron excitability was not altered, even during the maximal tension KT application on the soleus muscle. Thus, the tension used during a KT application should not be a concern in terms of modulating the sensorimotor activity ascribed to elastic taping during lying and standing postures.