The Effects of Caffeine Supplementation on Exercise Physiology and Time-trial Performance in a Hot Environment
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 15
- 主要终点
- Heart rate
研究概览
简要总结
Maintaining a stable core temperature is vital for physiological function; yet, exercise in heat can be problematic, and there is risk of exertional heat-related illness (Flouris & Schlader, 2015; Leyk et al., 2019; Périard et al., 2021; Tyler et al., 2016; Veltmeijer et al., 2015). While aerobic fitness improves heat tolerance (Alhadad et al., 2019), strategies like acclimation and pre-cooling also mitigate heat stress (Casadio et al., 2016; Lorenzo et al., 2010; Ross et al., 2013; Siegel et al., 2010). Caffeine, an ergogenic aid (Del Corso et al., 2011; John et al., 2024), is known to enhance performance via adenosine antagonism and increased catecholamines in normothermic environments (Fredholm et al., 1999; Graham & Spriet, 1991). However, effects in heat are inconsistent (Ganio et al., 2009; Zhang et al., 2014), possibly due to caffeine reducing the ability to thermoregulate effectively. Therefore, the aim of this study is to investigate the effects of a moderate dose of caffeine (5 mg/kg) on thermoregulation during a 30-minute running time trial in 35°C heat.
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
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Healthy trained runners
排除标准
- 未提供
研究组 & 干预措施
Caffeine
5 mg/kg dose of caffeine (in pill form)
干预措施: Thermoneutral environment (Other)
Caffeine
5 mg/kg dose of caffeine (in pill form)
干预措施: Hot environment (Other)
Placebo
5 mg/kg dose of placebo (maltodextrin - in pill form)
干预措施: Hot environment (Other)
Placebo
5 mg/kg dose of placebo (maltodextrin - in pill form)
干预措施: Thermoneutral environment (Other)
结局指标
主要结局
Heart rate
时间窗: From baseline to completion, up to 31 days
Change from baseline in heart rate measured at rest and at five different exercise intensities (65, 70, 75, 80, and 85% percent of maximal oxygen uptake) on a treadmill.
Rating of perceived exertion
时间窗: From baseline to completion, up to 31 days
Change from baseline in rating of perceived exertion measured (using the 6-20 Borg scale) at five different exercise intensities (65, 70, 75, 80, and 85% percent of maximal oxygen uptake) on a treadmill.
Blood lactate concentration
时间窗: From baseline to completion, up to 31 days
Change from baseline in blood lactate concentration measured at rest and at five different exercise intensities (65, 70, 75, 80, and 85% percent of maximal oxygen uptake) on a treadmill.
Oxygen uptake
时间窗: From baseline to completion, up to 31 days
Change from baseline in oxygen uptake measured at five different exercise intensities (65, 70, 75, 80, and 85% percent of maximal oxygen uptake) on a treadmill.
Time trial performance
时间窗: From baseline to completion, up to 31 days
Change from baseline in distance covered during a 30 minute time trial on a treadmill.
次要结局
未报告次要终点