Cardiorespiratory &Fitness
VO2 max, or maximal oxygen uptake, is the maximum rate at which your body can consume oxygen during intense exercise. Measured in milliliters of oxygen per kilogram of body weight per minute (mL/kg/min), it represents the upper limit of your aerobic energy system. VO2 max is widely considered the gold standard measurement of cardiorespiratory fitness and is one of the single most powerful predictors of all-cause mortality—more predictive than traditional risk factors like smoking, hypertension, or diabetes.
Your VO2 max reflects the integrated capacity of your cardiovascular system (heart pumping blood), respiratory system (lungs oxygenating blood), and skeletal muscles (utilizing oxygen for energy). During a VO2 max test, you exercise at progressively increasing intensity until you reach exhaustion, while oxygen consumption and carbon dioxide production are measured. The point at which oxygen consumption plateaus despite increasing workload is your VO2 max. This metric can also be estimated through submaximal tests or algorithms used by fitness trackers and wearables.
Research consistently demonstrates that higher VO2 max is associated with dramatically reduced mortality risk across all age groups. For every 1 MET (metabolic equivalent, roughly 3.5 mL/kg/min) increase in cardiorespiratory fitness, mortality risk decreases by approximately 10-15%. Elite endurance athletes may have VO2 max values exceeding 80 mL/kg/min, while sedentary individuals often fall below 35 mL/kg/min. The good news:VO2 max is highly trainable at any age through consistent aerobic and high-intensity interval training, making it one of the most modifiable longevity biomarkers.
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| Range Type | Level | Clinical Significance |
|---|---|---|
| Reflects integrated cardiovascular, respiratory, and muscular fitness | Highly trainable and modifiable at any age | Predicts healthy aging, cognitive function, and disease resistance |
| Optimal VO2 Max Ranges | Men:>35 mL/kg/min, Women:>30 mL/kg/min (general population) | Men:>50 mL/kg/min, Women:>40 mL/kg/min (excellent fitness) |
| Men:<25 mL/kg/min, Women:<20 mL/kg/min (very poor, high mortality risk) | VO2 max varies by age, sex, and genetics. Elite endurance athletes:60-85+ mL/kg/min. Longevity-focused targets for middle age:Men >45 mL/kg/min, Women >35 mL/kg/min. Each decade of age typically reduces VO2 max by ~10% in sedentary individuals, but only 5% in active individuals. Percentile rankings available by age/sex (top 25% correlates with lowest mortality). | High-Intensity Interval Training (HIIT) |
| Perform HIIT workouts 2-3 times weekly:4-8 intervals of 3-5 minutes at 85-95% max heart rate with equal recovery periods. HIIT produces the largest VO2 max gains, typically 5-15% improvement in 8-12 weeks. Norwegian 4x4 protocol (4 intervals of 4 minutes at 90% max HR) is highly effective. | Consistent Aerobic Base Training | Build aerobic capacity with 3-5 weekly sessions of moderate-intensity cardio (60-75% max HR) for 30-60 minutes. Activities like running, cycling, swimming, rowing develop the foundation for VO2 max improvements. Zone 2 training enhances mitochondrial density and fat oxidation capacity. |
Standard lab range:Excellent (men):>50 mL/kg/min, Excellent (women):>40 mL/kg/min, Elite athletes:60-85 mL/kg/min
Gradually increase training volume and intensity over weeks and months. Use periodized training blocks alternating between high-intensity and recovery phases. Avoid plateaus by varying workouts, adding cross-training, and incorporating progressive challenges every 4-6 weeks.
Reduce excess body fat to improve relative VO2 max (mL/kg/min). Each kilogram of weight loss in overweight individuals can increase VO2 max by 1-2 mL/kg/min without fitness changes. Maintain or build lean muscle mass through resistance training to support metabolic health.
Consider altitude training (live high, train low) for advanced improvement. Prioritize recovery through adequate sleep (7-9 hours), proper nutrition, and stress management. Chronic stress, poor sleep, and overtraining can suppress VO2 max gains and impair cardiovascular adaptation.
Low VO2 max (<25-30 mL/kg/min):early fatigue during physical activity, shortness of breath with exertion, reduced exercise tolerance, increased cardiovascular disease risk, higher all-cause mortality
Sedentary lifestyle, aging (especially without exercise), obesity, cardiovascular disease, chronic lung disease, anemia, deconditioning, heart failure, metabolic disorders
Note: VO2 Max and All-Cause Mortality
Note: Mandsager et al., "Association of Cardiorespiratory Fitness with Long-term Mortality,"JAMA Network Open, 2018
Research demonstrating strong association between higher cardiorespiratory fitness and preserved cognitive function, larger brain volume, and reduced dementia risk in aging populations. Each MET increase in fitness associated with 14% lower dementia risk.
Source:Defina et al., "Association of Cardiorespiratory Fitness with Dementia Risk,"Alzheimer's &Dementia, 2013
Prospective cohort studies showing that high cardiorespiratory fitness protects against cardiovascular disease, cancer, diabetes, and premature death. Fitness provides protection even in presence of traditional risk factors like obesity and hypertension.
Source:Ross et al., "Importance of Assessing Cardiorespiratory Fitness,"Circulation, 2016
Analysis demonstrating linear dose-response relationship between VO2 max and mortality across the entire fitness spectrum, with no plateau. Every 1 MET increase reduces mortality by 10-15%, with greatest benefits in moving from low to moderate fitness.
Source:Kodama et al., "Cardiorespiratory Fitness as Quantitative Predictor of Mortality,"Medicine &Science in Sports &Exercise, 2009
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| Provider | Includes Test | Annual Cost | Total Biomarkers |
|---|---|---|---|
 Superpower | — | $199 | 100+ |
 WHOOP Advanced Labs | — | $349 | 65 |
 Labcorp OnDemand | — | $398 | 30+ |
| — | $486 | 40+ | |
| — | $468 | 83 | |
| — | $798 | 100+ | |
 InsideTracker | — | $680 | 48 |
 Function Health | — | $499 | 100+ |
| — | $900 | 70+ | |
| — | $1150 | 110 | |
| — | $Varies | 75+ |
This information is for educational purposes only and is not medical advice. Always consult with a qualified healthcare provider about your specific health needs and before making decisions about blood testing.
