YMCA Cycle Ergometer Test Calculator (Submaximal Bike Test)
Estimate VO2max from the YMCA submaximal bike test: enter two stage workloads and steady-state heart rates to extrapolate maximal workload and predicted VO2max.
How it works
HRmax = 220 − age · Wmax = W₂ + (HRmax − HR₂) × (W₂ − W₁) ÷ (HR₂ − HR₁) · VO2max = 1.8 × Wmax (kg·m/min) ÷ body mass (kg) + 7 · 1 W = 6.12 kg·m/min
The YMCA cycle ergometer test is a multistage submaximal bike test: 3-minute stages at 50 rpm, starting at 25 W, with the next workloads chosen from the heart rate at the end of stage 1. Two steady-state heart rates between about 110 bpm and 85% of the age-predicted maximum are plotted against workload, and the straight line is extended to 220 − age. The ACSM leg-cycling equation then converts that maximal workload into VO2max.
Worked example
A 70 kg, 40-year-old rider reaches 120 bpm at 75 W and 135 bpm at 100 W. HRmax = 180 bpm, so Wmax = 100 + (180 − 135) × 25 ÷ 15 = 175 W = 1,071 kg·m/min. VO2max = 1.8 × 1,071 ÷ 70 + 7 = 34.5 ml/kg/min (2.42 L/min).
Sources: ACSM's Guidelines for Exercise Testing and Prescription — submaximal cycle ergometer testing and leg-cycling metabolic equation · Beekley MD et al. (2004) Cross-validation of the YMCA submaximal cycle ergometer test to predict VO2max. Res Q Exerc Sport 75:337–342
Frequently asked questions
How is the YMCA bike test done?
Pedal at 50 rpm on a calibrated ergometer (Monark type). Stage 1 is 25 W (150 kg·m/min) for 3 minutes; the heart rate at its end sets stage 2, and each later stage adds 25 W. Record heart rate in the last 15–30 seconds of minutes 2 and 3 of each stage, and stop once two stages give heart rates between 110 bpm and 85% of your maximum.
Which two stages should I enter?
The last two stages that reached a steady heart rate (minutes 2 and 3 within 6 bpm) and fell between 110 bpm and 85% of 220 − age. Enter the lower workload first.
Why can the result be off?
The method assumes a linear heart-rate response and a maximum of 220 − age; individual maximal heart rates vary by ±10–12 bpm, which can shift predicted VO2max by 15% or more. It is best used to track change in the same person.
Can I enter kg·m/min instead of watts?
Divide kg·m/min by 6.12 to get watts — for example 450 kg·m/min ≈ 75 W — and enter the watts.
Related calculators
This calculator gives an estimate for general fitness and education only. It is not a diagnosis — field tests and prediction equations can differ from laboratory measurements, so talk to a doctor or qualified exercise professional before acting on the result, especially before maximal testing.