Effect of hyperbaric oxygen on oxygen uptake and measurements in the blood and tissues in a normobaric environment.

Objective: To examine venous partial pressure of oxygen (Pvo2), transcutaneous oxygen tension (tcPo2), and VO2MM in a normobaric environment after a single hyperbaric oxygen (HBo2) treatment. Methods: This was a prospective study of conditions after the intervention compared with baseline. The participants were 10 moderately trained (Vo2MAS = 57.6 mI/kg/min) men. Two HBo2 treatments consisting of breathing 95% oxygen at 2.5 atmospheres absolute (ATA) for 90 minutes were administered on non-consecutive days. Baseline testing included measures of Vo2MAX, tcPo2, and anthropometry. At 6.0 (1 .0) minutes after the first HBo2 treatment, a Vo2MAX test was performed. After the second HBo2 treatment, leg and chest tcPo2 and Pvo2 were monitored for 60 minutes. Results: Vo2MAX, running time, and peak blood lactate were not altered after the HBo2 treatment. Leg tcPo2 was lower (p = 0.003) and chest tcPo2 was unchanged after the HBo2 treatment compared with baseline values. Pvo2 was significantly (p<0.001) lower in the first three minutes after treatment than subsequent values, but no other differences were found. Conclusions: A single HBo2 treatment at 2.5 ATA for 90 minutes does not raise Pvo2, tcPo2, or Vo2MAX in a normoboric, normoxic environment. [ABSTRACT FROM AUTHOR]