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Postexercise Hot-Water Immersion on Exercise Performance in Hypoxia

Not Applicable
Not yet recruiting
Conditions
Heat Exposure
Exercise Training
Registration Number
NCT06672614
Lead Sponsor
Nipissing University
Brief Summary

The purpose of this study is to determine the effect of 5 days post-exercise hot water immersion on exercise performance at simulated altitude.

Detailed Description

Human performance is compromised at altitude due to a lower partial pressure of oxygen and subsequent reductions in the convective transport of oxygen to tissue. Long-term acclimation to attitude incurs physiological adaptations that result in a near return to sea-level performance; however, the time required (\~2 weeks) for such adaptations is often logistically challenging for athletes, military personnel or other individuals who reside at sea level. Recent research suggests that physiological acclimation to heat stress (i.e., heat acclimation) and altitude (i.e., hypoxia) share similar cellular adaptations, namely an up-regulation of Hypoxia-inducible factor 1 (HIF-1) and various heat shock proteins. Therefore, it is hypothesized that heat acclimation may provide physiological protection from reduced oxygen transport to the tissue and enhance performance at altitude. This cross-tolerance model is supported by traditional heat acclimation protocols (i.e., submaximal exercise in hot ambient temperature); however, it has not been tested with passive exposure to heat stress through post-exercise hot water immersion.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
20
Inclusion Criteria
  • Physically active (minimum of 90 minutes of moderate-intensity exercise per week)
Exclusion Criteria
  • Cardiovascular disease
  • resident of >1500 m above sea-level in the past year;
  • history of fainting

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
Time-Trial Performance in hypoxia conditions30 minutes

Results of a 16 km time-trial test conducted at an fraction of inspired oxygen (FiO2) of 0.14

Secondary Outcome Measures
NameTimeMethod
Heart Rate during exercise90 minutes

Heart rate will be measured throughout the time trial tests and exercise training interventions using a wireless (Polar) heart rate chest strap.

Skin temperature during exercise90 minutes

Skin temperature measured throughout the time trial-tests and exercise training intervention using temperature probes attached to the calf, thigh, chest and arm, from which weighted averages are calculated.

Core temperature during exercise90 minutes

Core body temperature measured throughout the time-trial tests and exercise training interventions using a rectal temperature probe.

Pulse oxygen saturation during exercise30 minutes

Capillary oxygen saturation measured on the earlobe throughout the time-trial tests using pulse oximetry.

Trial Locations

Locations (1)

Nipissing University

🇨🇦

North Bay, Ontario, Canada

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