Vo2 requirement at different displayed power outputs on five cycle ergometer models: a preliminary study.

Area of Science:

• Exercise Physiology
• Biomedical Engineering
• Sports Science

Background:

• Accurate measurement of power output is crucial for standardized exercise testing and physiological research.
• Cycle ergometers are widely used, but their accuracy can vary significantly between brands.

Purpose of the Study:

• To evaluate the validity of five different cycle ergometer brands.
• To compare the oxygen consumption (Vo(2)) requirements at various displayed power outputs (PO).

Main Methods:

• Five physically active men underwent continuous incremental exercise tests on five ergometers.
• Vo(2) was measured, and steady-state values were used to create Vo(2)-watt curves.
• One ergometer (CompuTrainer) was compared to a dynamometer for real power assessment.

Main Results:

• Significant differences (5-10 ml kg(-1) min(-1)) in Vo(2) were observed at the same displayed PO across ergometers.
• CompuTrainer underestimated PO by ~30W, while Lifecycle overestimated it by 3-53W (100-300W).
• Monark and Polar S710 underestimated PO by 15W; Ergomeca underestimated by ~5W.

Conclusions:

• Displayed PO inaccuracies ranged from -10% to 18% across tested cycle ergometers.
• These discrepancies question the interchangeability of different ergometer brands for research and clinical use.