Metabolic exercise testing is traditionally performed in a laboratory environment with cumbersome, expensive equipment. CardioCoach™ is a portable, light weight, and economical metabolic exercise testing device that may be more practical for use in non-laboratory environments.
To validate the CardioCoach™ metabolic testing system with the Medical Graphics Cardio II metabolic system at both sub-maximal and maximal intensities.
Ten volunteers [5 women (23.2±2.9 years; 57.5±3.5 kg) and 5 men (29.8±7.2 years; 77.2±10.6 kg)] visited the laboratory on two separate occasions, performing sub-maximal and maximal exercise tests on a cycle ergometer. The subjects were randomized to begin testing with either the CardioCoach™ or Medical Graphics Cardio II. The exercise test included three sub-maximal, three-minute stages (50, 75, 100 watts for women; 50, 100, 150 watts for men) followed by incremental, 25 watt, one-minute stages until volitional fatigue (VO2max). Gas was collected using the CardioCoach™ model 9000 (Korr Medical Technologies, Inc., Salt Lake City, Utah) with a Hans Rudolph one-way valve and silicone face mask and the Medical Graphics Cardio II (Medical Graphics Corporation, St. Paul, MA, BreezeSuite software version 6.0A). Both metabolic devices detected breath-by-breath gas analysis that was averaged in 15 second intervals. Heart rate was assessed using a Polar T31 heart rate monitor. VO2 values were recorded at the beginning of each stage and at volitional fatigue. Data were analyzed by paired t-tests at each workload and at VO2max using the 0.05 level of significance.
Measures of relative VO2 (ml/kg/min) were not significantly different between the CardioCoach™ and Medical Graphics Cardio II at submaximal workloads of 50, 75, 100, 150 watts (p > 0.13 for all measures) or maximal (VO2max) values (p > 0.84). All data reported as mean ± 1 SD.
The CardioCoach™ is a valid device for sub-maximal and maximal exercise testing on a cycle ergometer and may provide a feasible option for metabolic exercise testing outside the laboratory.