The Effects of Caffeine on Exercise Physiology and Time-trial Performance in a Hot Environment
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Hot environment, Thermoneutral environment.
- Who it may be relevant to
- Registry conditions: Caffeine, Thermoregulation. Basic parameters: 18 years — 45 years · Male.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Center list to be confirmed — check the primary protocol.
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
The Effects of Caffeine Supplementation on Exercise Physiology and Time-trial Performance in a Hot Environment
Overview
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.
Interventions
- Other Hot environment
Hot environment of 35 degrees Celsius - Other Thermoneutral environment
Thermoneutral environment of 18 degrees Celsius
Primary outcome measures
- Blood lactate concentration [Time frame: From baseline to completion, up to 31 days]
- Heart rate [Time frame: From baseline to completion, up to 31 days]
- Rating of perceived exertion [Time frame: From baseline to completion, up to 31 days]
- Oxygen uptake [Time frame: From baseline to completion, up to 31 days]
- Time trial performance [Time frame: From baseline to completion, up to 31 days]
Eligibility criteria
Inclusion criteria
- Healthy trained runners
Exclusion criteria
\-
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Double blind
- Primary purpose
- Basic science
Study locations
Center list to be confirmed — check the primary protocol.
Identifiers
NCT: NCT07129200 · SMU_ETHICS_2024-25_1111