Browsing by Author "Guo L"

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    Effect of Caffeinated Chewing Gum on Maximal Strength, Muscular Power, and Muscle Recruitment During Bench Press and Back Squat Exercises
    (MDPI (Basel, Switzerland), 2025-07-28) Ding L; Liu J; Ma Y; Lei T-H; Barnes M; Guo L; Chen B; Cao Y; Girard O
    Background/Objectives: This study aims to investigate the effects of caffeinated chewing gum on maximal strength, muscular power, and neural drive to the prime movers during bench press and back squat in resistance-trained men. Methods: Sixteen resistance-trained males participated in a double-blind, randomized trial, chewing either caffeinated gum (4 mg/kg) or placebo gum on two separate occasions, seven days apart. After chewing for 5 min, participants performed a maximal strength test followed by muscular power assessments at 25%, 50%, 75%, and 90% of their one-repetition maximum (1RM), completing with 3, 2, 1, and 1 repetition (s), respectively, for bench press and back squat. Surface electromyography data were recorded for each repetition. Results: Caffeinated gum did not significantly improve one-repetition maximum (1RM) for bench press (p > 0.05), but increased mean frequency (MF) and median frequency (MDF) in anterior deltoid, pectoralis major, and biceps brachii (all p < 0.05) compared to placebo. For back squat, 1RM increased with caffeinated gum, along with higher MF and MDF in vastus medialis (all p < 0.05). Caffeinated gum also improved mean and peak velocities, and mean and peak power outputs at 25–75% 1RM during the bench press (all p < 0.05), along with elevated MDF in pectoralis major and biceps brachii (all p < 0.05). Similar improvements were seen in mean and peak velocities during the back squat at 25–90% 1RM (all p < 0.05), along with higher MF and MDF in vastus medialis and increased normalized root mean square activity in gluteus maximus (all p < 0.05). Conclusions: Caffeinated chewing gum (4 mg/kg) enhanced muscular power (25–75% 1RM) in the bench press and improved maximal strength and muscular power (25–90% 1RM) in the back squat by increasing muscle recruitment in resistance-trained men.
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    Semi-Acquaintance Society in Rural Community-Based Tourism: Case Study of Moon Village, China
    (MDPI (Basel, Switzerland), 2023-03-11) Li T; Wu B; Guo L; Shi H; Chen NC; Hall CM
    Tourism development provides a unique context for studying guanxi in acquaintance society in rural areas in China. Taking the case of Moon village from the perspective of guanxi, this study conducted a qualitative study to analyze the structural characteristics of the semi-acquaintance society in the tourism context. A buffer guanxi circle develops when strangers immerse themselves into an acquaintance-based society through social interaction, where affection and reasoning define the boundary, guanxi and the interests on which the social consensus is based, as well as the elite and collective actions vitalizing the community. These findings on how the semi-acquaintance society contributes to guanxi imply a co-governance structure for informal relations in governance in community-based rural tourism.