Gas Exchange During Maximal Upper Extremity Exercise (3)Most exercised regularly (jogging, basketball, calisthenics), but none would be considered an elite athlete. All subjects acknowledged voluntary participation in this study by giving informed written consent. The protocol was approved by the Investigational Review Board and Human Use Committees of the William Beaumont Army Medical Center, El Paso, Texas, and the Health Service Command, San Antonio, Texas.
The study was conducted in the human performance laboratory of the William Beaumont Army Medical Center at an altitude of 1,270 meters. The average laboratory temperature was 23°C and mean barometric pressure of 656 mm Hg (mean PlOs, 128 mm Hg). Details for both the maximal progressive arm crank exercise protocol used in the present study and for the lower extremity exercise used in the previous study have been described previously. buy birth control online
Subjects arm cranked on a mechanically braked cycle ergometer that had been mounted on a steel stand. Subjects sat behind the ergometer with the crank shaft at shoulder height and cranked at a rate of 70 rpm. Beginning with no added resistance (0 watts), the work rate or “power,” was increased by 34 W every 2 minutes until the subject could not maintain the 70 rpm crank rate.