Intermittent Cooling During Baseball Games Alleviated Perceived Exertion But Had no Effect on Hitting and Defense Performance in Hot Environment
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 10
- 试验地点
- 2
- 主要终点
- rectal temperature
研究概览
简要总结
This study adopted a practical approach in intermittent cooling on forehead and neck during an intra-squad baseball game. Exit velocity of batted balls was used as an indicator for hitting performance and a baseball-specific reactive agility test to evaluate the cognitive performance in defense.
详细描述
This study used a randomized cross-over design. Each participant completed a cooling and a non-cooling trial in a random order, separated by a 20-day washout period. Each trial contained a 7-inning intra-squad game in hot environment. Hitting, reactive agility, and cognitive tests were administered before and after the game. Forehead skin and tympanic temperature, perceived exertion, and thermal sensation were measured during the game.
Experimental procedure After body weight and rectal temperature were measured in a temperature-controlled room, the participants consumed a standardized breakfast. The breakfast included white bread 1.2 g/kg, jam 0.1 g/kg, butter 0.l g/kg, and soybean milk 5 ml/kg (6.2 kcal/kg, containing carbohydrate 1.0 g/kg, protein 0.24 g/kg, and fat 0.14 g/kg). Go/NoGo and Stroop Color-Word tasks were administered after breakfast. After finishing the cognitive tests, the participants moved to the field for self-selected warm up, followed by hitting and reactive agility tests. After the intra-squad game, the participants repeated the hitting, reactive agility, and cognitive tests. The participants can drink water ad libitum during the experimental period.
Intra-squad game The 7-inning intra-squad games were played under the standard rules of baseball in hot environmental conditions (temperature 31.1-33.4℃, humidity 63-67%).
Cooling intervention The participants in the cooling trial put cold towels on their forehead and neck for 3 min in the shaded dugout during their offensive half innings when they were not scheduled to hit or on base. Each participant received the cooling intervention 3 to 4 times in each game. After each use, the towels were kept in a cooler that contained water mixed with ice and salt to keep the temperature at approximately 0℃. The participants in the control trial sat in the shaded dugout without any cooling intervention.
Measurement of temperature Rectal temperature was measured before breakfast and after the game with a digital thermometer fitted with disposable sheaths. Forehead skin and tympanic temperature were measured with infrared thermometers during their offensive half innings in the dugout.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 20 Years 至 23 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •baseball players from National Taiwan University of Sport, Taiwan
- •at least 6 years of experience in baseball training
- •have competed nationally.
排除标准
- •having cardiovascular or other known chronic diseases
- •taking any medication in the preceding 2 months
- •having musculoskeletal injuries in the preceding 2 months.
结局指标
主要结局
rectal temperature
时间窗: baseline
forehead skin temperature
时间窗: baseline
swing power
时间窗: baseline
power of bat swings
change in swing power
时间窗: 3 hours after baseline
power of bat swings
tympanic temperature
时间窗: baseline
change in tympanic temperature
时间窗: 2 hours after the baseline
measured after each inning in an 2-hour 7-inning intra-squad baseball game
change in rectal temperature
时间窗: 5 hours after the baseline
change in forehead skin temperature
时间窗: 2 hours after the baseline
measured after each inning in an 2-hour 7-inning intra-squad baseball game
change in exit velocity of batted balls
时间窗: 3 hours after baseline
exit velocity of batted balls
时间窗: baseline
reactive agility in defense
时间窗: baseline
The reaction time, the time from bat-ball contact to the participant's first definitive movement in the intended direction
change in reactive agility in defense
时间窗: 3 hours after baseline
The reaction time, the time from bat-ball contact to the participant's first definitive movement in the intended direction
次要结局
- Go/NoGo tasks(baseline)
- ratings of perceived exertion(baseline)
- change in thermal sensation(2 hours after baseline)
- Stroop Color-Word test(baseline)
- change in Go/NoGo tasks(5 hours after baseline)
- change in ratings of perceived exertion(2 hours after baseline)
- thermal sensation(baseline)
- change in Stroop Color-Word test(5 hours after baseline)
研究者
Chen Kang
Professor
National Taiwan Sport University