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The purpose of this study was to compare the efficacy of four cooling interventions used for reducing physiological and perceptual strain and improving exercise performance during outdoor match-play tennis in the heat. Eight competitive tennis players played four counter-balanced simulated outdoor matches in the heat (WBGT: 28.4–32.5°C) at 24- or 48-h intervals. Each match comprised 3 sets for which the "no-ad" rule was applied to limit duration variability. Players underwent the following cooling interventions: ad libitum fluid ingestion (CON), ad libitum fluid ingestion and ice vest (VEST), total ingestion of approximately 1000 g ice slurry and ice vest (Combined: BINE), or total ingestion of approximately 400 g ice slurry and ice vest (Low-combined: L-BINE). Gastrointestinal temperature was lower in the BINE and the L-BINE trials than in the CON trial at the set-break of set 1, and these differences in gastrointestinal temperature persisted throughout the remainder of the match (p < 0.05). The ratio of moderate-high intensity activity (≥10 km/h) in set 3 was significantly higher in the L-BINE trial than that in the BINE trial (p < 0.05). In the CON and BINE trials, high intensity activity was significantly lower in set 3 compared with set 1 and 2, respectively. Cooling by optimal ice slurry ingestion and ice vest may be a more effective strategy in mitigating the development of heat strain during outdoor match-play tennis in the heat. Highlights Cooling by optimal ice slurry ingestion and ice vest may be a more effective strategy in mitigating the development of heat strain during outdoor match-play tennis in the heat. Ingesting of large amounts ice slurry may be caused the bloating and stomach discomfort, in turn declined in the ratio of moderate-high intensity activity in the second half of match-play tennis in hot outdoor environments. Future studies should not only utilize match characteristics, but also measure on-court tennis specific performance. [ABSTRACT FROM AUTHOR]

Purpose: Yoga stretching can be done comfortably and easily by beginners and older adults to compensate for lack of exercise or poor health maintenance. The aim of this study was to determine the effect of yoga stretching on mucosal immune functions, primarily human β-defensin 2 (HBD-2) in saliva. Methods: Fifteen healthy adults (age, 60.4 ± 8.0 years) participated in the study. Participants rested for 90 min on the first day and performed yoga for 90 min on the second day. Measurements were carried out before and after rest or yoga. Saliva samples were collected by chewing a sterile cotton at a frequency of 60 cycles per min. Salivary HBD-2 concentration was measured using an enzyme-linked immunosorbent assay. Results: HBD-2 concentration after yoga stretching (165.4 ± 127.1 pg/mL) was significantly higher than that before yoga stretching (84.1 ± 63.4 pg/mL; p < 0.01). HBD-2 expression rate after yoga stretching (232.8 ± 192.9 pg/min) was significantly higher than that before yoga stretching (110.7 ± 96.8 pg/min; p < 0.01). HBD-2 concentration ( p < 0.05) and HBD-2 expression rate ( p < 0.01) at post on the second day (yoga) was significantly higher than that on the first day (rest). POMS score of anger-hostility was lower after yoga than before. Conclusions: Yoga stretching for 90 min can increase salivary HBD-2 expression in older adults. Therefore, yoga stretching might be useful for older adults and athletes to maintain their health. [ABSTRACT FROM AUTHOR]