Hematological Adaptations to Post-Exercise Sauna Bathing With No Fluid Intake: A Randomized Cross-Over Study

Area of Science:

• Sports Science
• Exercise Physiology
• Heat Therapy

Background:

• Sauna bathing is often recommended for athletes to enhance training.
• Empirical evidence supporting its effectiveness in improving sports performance remains inconclusive.
• This study investigates the physiological impact of post-exercise sauna use.

Purpose of the Study:

• To examine the effects of post-exercise sauna bathing on hematological adaptations.
• To assess the impact on exercise capacity in healthy male athletes.
• To determine if sauna bathing offers additional benefits beyond endurance training alone.

Main Methods:

• A randomized cross-over study involving 13 physical education students.
• Two 4-week interventions: stationary cycling with or without post-exercise sauna bathing (30 min).
• Measurements included total hemoglobin mass, erythropoietin, ferritin, red blood cell parameters, and graded exercise test variables.

Main Results:

• Total hemoglobin mass increased, and ferritin concentration decreased irrespective of sauna use.
• Maximal power, power at gas exchange threshold, and peak oxygen uptake improved with training alone.
• Changes in total hemoglobin mass were within the typical error range (<1.8%).

Conclusions:

• Post-exercise sauna bathing with fluid restriction does not provide additional benefits over endurance training.
• Hematological and exercise capacity improvements are primarily driven by the training stimulus.
• Further research is needed to validate recommendations for post-exercise sauna conditioning strategies.