VO₂max Estimator
Cooper (12 min) · Rockport (walk) · Race time · MAS/VMA - ACSM category · 5K, Marathon & HYROX projections
VO₂max (maximal oxygen uptake) is the gold-standard measure of aerobic capacity. Expressed in mL/kg/min, it quantifies the maximum amount of oxygen your body can use during intense exercise. The higher it is, the more energy your muscles can produce aerobically - directly translating to running and HYROX performance.
This tool offers four scientifically validated estimation protocols: the Cooper test (12 minutes of running), the Rockport walking test (1.6 km), race-time estimation using the Jack Daniels formula, and MAS (Maximal Aerobic Speed) estimation. Each method has its strengths - choose the one that fits your available data.
Once your VO₂max is estimated, the tool compares it to ACSM norms by age and gender, and automatically generates performance projections for 5K, 10K, half marathon, marathon, and HYROX. These projections use the inverse Jack Daniels formula and represent achievable performances under ideal conditions.
Related guide
Preparing Your First Hyrox®: the Complete Guide12-week programme, equipment, nutrition, race day tipsFrequently asked questions about VO₂max
What is VO₂max and what is it used for?+
VO₂max is the maximal oxygen uptake expressed in mL/kg/min. It is the primary indicator of cardiovascular and aerobic capacity. A VO₂max of 50 mL/kg/min for a 35-year-old male falls in the 'excellent' category according to ACSM norms. It largely determines your endurance performance and can be significantly improved through training.
What is the difference between the 4 estimation protocols?+
The Cooper test (12 min run) is accurate but requires maximal effort. The Rockport walk test (1.6 km) is ideal for sedentary individuals or those returning to exercise. Race-time estimation (Jack Daniels formula) is very reliable if you have a recent competition time. MAS is practical if you regularly do field tests. All methods are estimates - only a lab test (direct VO₂max) is 100% precise.
How do I improve my VO₂max?+
VO₂max improves primarily through Zone 2 training (base endurance, 60-70% HRmax) at high volumes, and high-intensity interval sessions (Zone 4-5, 90-100% HRmax). Formats like 30/30 intervals, 3-5 minute intervals at MAS, and long weekly runs are the most proven methods. Gains of 10-20% are achievable in a few months for beginners.
What VO₂max is needed to perform well in HYROX?+
HYROX finishers under 60 minutes typically have a VO₂max above 50 mL/kg/min (excellent or superior category). A VO₂max of 40-50 allows finishing in 60-75 minutes with specific training. Below 40, the running segments become very demanding. VO₂max isn't everything - functional strength for the stations is equally decisive.
Are the performance projections reliable?+
Projections are based on the Jack Daniels formula (Daniels & Gilbert, 1979), a scientific reference validated on thousands of athletes. They represent achievable performances under ideal conditions: flat course, neutral weather, optimal pacing. In practice, fatigue level, racing experience, pacing discipline, and race-day conditions can shift the result by ±5-10%.
What is the average VO₂max for a 40-year-old man or woman?+
According to ACSM norms, the average VO₂max for a 40-year-old man is approximately 36-44 mL/kg/min ("average" category). For a 40-year-old woman, the average is 30-38 mL/kg/min. These values naturally decline by roughly 1% per year after age 30 without training, but a regular endurance programme can slow or partially reverse this decline.
Can you improve your VO₂max after 50?+
Yes, absolutely. Recent studies show gains of 10-15% in VO₂max are achievable in adults over 50 with a structured programme combining Zone 2 and high-intensity intervals. The magnitude of improvement is generally smaller than at 25, but the cardiovascular and performance benefits remain significant. After 50, maintaining VO₂max is just as important as improving it.