None listed
Conditions
Brief summary
This study aimed to test whether passive increases in muscle and core temperature following a single session of hot-water immersion affect force steadiness and motor unit discharge rate variability. It was hypothesized that increased muscle temperature would impair force steadiness and increase the coefficient of variation in motor discharge rates. Additionally, it was expected that elevated core temperature would exacerbate these changes due to central activation fatigue. To test these hypotheses, the study evaluated force steadiness and motor unit discharge rate variability immediately after a 90-minute hot-water immersion at 42ºC, with elevated muscle and core temperatures, and again 15 minutes later, when muscle temperature remained elevated but core temperature had returned to baseline.
Interventions
Participants attended two water immersion sessions, each lasting 90 minutes, with temperatures set at 36°C and 42°C in a counterbalanced order. A washout period of 7 days was maintained between sessions. Core temperature and thermal sensation were monitored throughout each session. If a participant felt uncomfortable with the heat or their core temperature reached 39.5°C, the session would be ended.
Each immersion session was conducted in a laboratory setting at an ambient temperature of 23°C.
Participants attended two water immersion sessions, each lasting 90 minutes, with temperatures set at 36°C and 42°C in a counterbalanced order. A washout period of 7 days was maintained between sessions. Core temperature and thermal sensation were monitored throughout each session. If a participant felt uncomfortable with the heat or their core temperature reached 39.5°C, the session would be ended. Each immersion session was conducted in a laboratory setting at an ambient temperature of 23°C. Participants wore swimsuits and sat steadily in an inflatable bath during the 90 minutes. They were permitted to drink water ad libitum throughout the session and had an electric fan directed at their upper body to aid with thermal comfort.
Sponsors
Queensland University of Technology
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 39 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy adults.
Exclusion criteria
Medical conditions contraindicating heat stress, musculoskeletal injury, or pregnancy.
Outcome results
None listed