Build a base with low-intensity exercise
If you’re starting, prioritize longer, lower-intensity sessions like swimming, cycling, jogging, or rowing a few times a week. Consistency is key. Even three 30-minute workouts per week can lead to noticeable improvements if you were previously more sedentary than you’d like to be.
It’s worth noting that VO2 max itself can take months to improve, but you may notice changes sooner, like workouts feeling easier, faster recovery, or better energy levels. “Other indicators could include a lower resting heart rate or being able to perform movements faster, with more power, for longer periods,” says Bird.
Try Zone 2 training…
If you’re not an athlete, around 80% to 90% of your training should be low-intensity, steady-state cardio—often called Zone 2—where you can hold a conversation, but it’s not entirely comfortable. “I recommend a 40 to 45 minute session twice a week,” says Vaux. “This is great for building an aerobic base and boosting mitochondria in the muscle, which act as power stations for energy production.”
…and the Norwegian 4×4
When you’re not training in Zone 2, Vaux suggests maximal intervals. “The Norwegian 4×4 is popular right now,” he says. “You push as hard as you can for four minutes, then recover for three minutes—walk or jog—then go again, four times over.”
If four minutes feels like too much, start shorter, like 30 seconds, and build up gradually. “It takes years to slowly build up one’s physical system. Take your time,” he adds. “Be the tortoise, not the hare, and VO2 max will come.”
Do high-intensity training
“For athletes or people who already have a strong fitness base, it can be a much harder process—and often takes longer,” says Bird. “If you’re able to, research shows that high-intensity aerobic work is one of the most effective ways to improve VO2 max.”
This means working at 90% or more of your maximum heart rate in short bursts, followed by recovery. But recovery or rest days, restorative moments, and practices like foam rolling are key.
“These workouts place a lot of stress on the body, and when you don’t recover properly you increase the risk of overtraining or injury,” she says. “Gradually increasing the intensity or duration over time is important.”
Don’t forget strength training
Strength training won’t directly improve VO2 max, but it’s still essential. “Stronger muscles improve movement efficiency and overall work capacity, which can support better endurance performance,” says Stevens.
Vaux adds that muscle mass becomes even more important with age. “A high VO2 max will not help if you trip over and need to react quickly,” he says, noting that the biggest cause of death by injury in those over 65 is falling.
Maintaining muscle mass—particularly the fast-twitch kind, which gives us power—is crucial. If you can’t get to a gym, try using your bodyweight for strength training.
Breathe
There are few things that breathwork can’t help with, and training is no different. “Practices such as nasal breathing during running, diaphragmatic or box breathing can help improve lung efficiency, CO2 tolerance and reduce perceived cardiovascular strain, supporting your ability to train effectively, even if they don’t directly raise VO2 max,” says Bird.