Key takeaways
Untrained adults commonly gain 10 to 20% in VO2max in a few months; trained runners gain less but still gain
Intervals at 90 to 95% of max heart rate, such as the 4×4, are the most direct VO2max stimulus
Three runs a week for twelve weeks beats six runs a week for three; a few ml/kg/min is a realistic 12-week gain
VO2max responds to training in almost everyone. Untrained adults commonly gain 10–20% in a few months; trained runners gain less, but still gain. The recipe is not secret. It comes down to five principles and the patience to apply them for twelve weeks.
The five principles
- Volume. Easy aerobic running builds the base: more blood volume, a bigger stroke volume, more capillaries and mitochondria in the muscles. Most of your weekly time should be easy. See 80/20 training.
- Intervals. Work at 90–95% of maximum heart rate pushes the heart close to its maximum output and is the most direct stimulus for VO2max. Meta-analyses find intervals raise VO2max more than steady moderate training of similar duration. The Norwegian 4×4 is the best-studied session.
- Consistency. Gains come from weeks of repeated stimulus, and they fade within weeks of stopping. See how fast you lose VO2max. Three runs a week for twelve weeks beats six runs a week for three.
- Body weight. VO2max is expressed per kilogram, so losing excess fat raises the number even if your heart doesn't change. See VO2max and body weight.
- Recovery. Adaptation happens between sessions. Sleep, easy days and a lighter week every few weeks let the hard work pay off. Watch your resting heart rate and HRV.
Before you start
Get a baseline: a watch estimate, a field test such as the Cooper 12-minute run, or a recent race. The VO2max calculator turns any of these into an estimate. Then see where you sit on the VO2max chart by age and sex.
The plan below assumes you can already run 30 minutes continuously, three or four times a week. If not, spend four to eight weeks building up to that first, with run–walk if needed.
The 12-week plan
Easy = conversational pace. "4×4" = four 4-minute reps at 90–95% HRmax with 3 minutes jogging between. "Tempo" = comfortably hard, roughly the pace you could hold for an hour. Every hard session starts with a 10–15 minute warm-up and ends with a cool-down.
| Week | Run 1 | Run 2 | Run 3 | Run 4 (optional) |
|---|---|---|---|---|
| 1 | Easy 30 min | Easy 30 min + 4 strides | Long easy 45 min | Easy 25 min |
| 2 | Easy 30 min | 4×2 min hard, 2 min jog | Long easy 50 min | Easy 30 min |
| 3 | Easy 35 min | 4×3 min hard, 3 min jog | Long easy 55 min | Easy 30 min |
| 4 (lighter) | Easy 30 min | 3×3 min hard, 3 min jog | Long easy 45 min | Rest |
| 5 | Easy 35 min | 4×4 | Long easy 60 min | Easy 30 min |
| 6 | Easy 35 min | 4×4 | Long easy 60 min | Tempo 15 min within 35 min |
| 7 | Easy 40 min | 4×4, slightly faster | Long easy 65 min | Easy 30 min |
| 8 (lighter) | Easy 30 min | 3×4 min hard | Long easy 50 min | Rest |
| 9 | Easy 40 min | 5×4 | Long easy 70 min | Tempo 20 min within 40 min |
| 10 | Easy 40 min | 5×4 | Long easy 70 min | Easy 35 min |
| 11 | Easy 40 min | 6×3 min hard, 2 min jog | Long easy 75 min | Tempo 20 min within 40 min |
| 12 (test) | Easy 30 min | 3×4 min hard | Easy 30 min | Re-test |
Keep at least one easy day between hard sessions. If you add strength training, put it on the same day as a hard run or on a day you don't run, so your easy days stay easy.
Safety: if you have a heart condition, high blood pressure, chest pain, or have been inactive for a long time, get medical advice before starting intervals. Stop and seek help if you feel chest pain, faintness or an irregular heartbeat.
How to track progress
- Repeat the same test in week 12 under similar conditions: same course, similar weather, rested.
- Watch your 4×4 heart rate. The same pace at a lower heart rate, or a faster pace at the same heart rate, means you are fitter.
- Watch the trend, not the day. Watch estimates bounce around by a few points; see how accurate is your watch's VO2max.
A realistic result for a recreational runner is a gain of a few ml/kg/min over twelve weeks. Some people improve more, some less — see why some people improve more. If you barely moved, more weekly volume is usually the next step.
After week 12
Repeat the cycle with slightly more volume, or switch to a block focused on threshold or race pace. Keep one hard session a week to hold onto what you've gained.
Frequently asked questions
How long does it take to improve VO2max?
Most people see change within a few months of regular training. Over a 12-week plan, a realistic gain for a recreational runner is a few ml/kg/min, and untrained adults commonly gain 10 to 20% in a few months.
What is the best workout to increase VO2max?
Intervals at 90 to 95% of maximum heart rate push the heart close to its maximum output. Meta-analyses find they raise VO2max more than steady moderate training, and the Norwegian 4×4 is the best-studied session.
Can you increase VO2max by losing weight?
Yes. VO2max is expressed per kilogram, so losing excess fat raises the number even if your heart does not change.
Sources
- Helgerud J, et al. Aerobic high-intensity intervals improve VO2max more than moderate training. Med Sci Sports Exerc, 2007.
- Bacon AP, et al. VO2max trainability and high intensity interval training in humans: a meta-analysis. PLoS One, 2013.
- Milanović Z, et al. Effectiveness of high-intensity interval training (HIT) and continuous endurance training for VO2max improvements: a systematic review and meta-analysis of controlled trials. Sports Med, 2015.
- Seiler S. What is best practice for training intensity and duration distribution in endurance athletes? Int J Sports Physiol Perform, 2010.
- Mujika I, Padilla S. Detraining: loss of training-induced physiological and performance adaptations. Part I: short term insufficient training stimulus. Sports Med, 2000.