A Portable Unit to Measure Metabolic Rate during Shirtsleeve and Suited EVA Tests

This paper presents a new portable metabolic device (PUMA-Portable Unit for Metabolic Analysis) developed at the NASA Glenn Research Center. PUMA is a battery-operated, wearable unit to measure metabolic rate (minute ventilation, oxygen up-take, carbon dioxide output and heart rate) in a clinical setting, in the field or in remote, extreme environments. The critical sensors in PUMA are located close to the mouth and sampled at 10 Hz to allow intra-breath measurements. PUMA transmits metabolic data wirelessly to a remote computer for data analysis and storage. In addition to it's primary function as a portable metabolic measurement device, the PUMA sensors can also be easily adapted to other applications, including future EVA suits where they could measure metabolic rate for a suited crew member.

The first section of the paper discusses the specific technologies and innovations of PUMA. The second section presents the results of Human Subject Tests at the NASA Johnson Space Center Exercise Physiology Lab where PUMA was benchmarked against a commercial metabolic cart. Finally, results are presented for measurements of resting metabolic rate during the NASA Extreme Environment Mission Operations (NEEMO-12 and NEEMO-13) missions.