COMPARISON OF PORTABLE METABOLIC ANALYZERS DURING WALKING, JOGGING, AND RUNNING

Oxygen uptake (VO2) measurements enable performance professionals, clinicians, and scientists to quantify energy expenditure for various purposes. Devices that accurately detect the composition of expired gases and changes in VO2, open new possibilities in research methodology and accessibility. PURPOSE: The purpose of this study was to compare the VO2 measurements of the VO2 Master Pro (VM) to the Cosmed K5 (K5) during walking, jogging, and running in field and lab conditions. METHODS: Twelve proficient runners, with a current 10k pace of ≤ 5:19 min/km, performed 3 matched intervals at 3 different speeds (4.82, 8.05, 11.27 kph) on a treadmill and on an outdoor track. An airflow test was performed on both devices by pumping air through the devices using a 3 L syringe timed to a metronome at 15, 25, and 35 bt/min. The VM did not report walking data for most participants and was excluded from analysis. Jogging and running measurements were analyzed using a 2x2x2 repeated measures ANOVA. RESULTS: The indoor running analysis revealed significant differences in VO2 (3017 vs. 1880 ml/min), VE (71 vs 57 ml/min), and TV (1.89 vs 1.56 L) between the K5 and VM respectively (p < .05). Outdoor analysis showed a significant difference between devices in VO2, VE¬, and TV (p < .05). The airflow test showed significant differences between the devices in VE and TV (p < .05). Analysis failed to show a significant difference in FeO2 and HR (p > .05). CONCLUSION: These results suggest that there are significant discrepancies between the K5 and the VM, likely due to differences in TV measurement.