Age, health and weight

Is a VO2 max test safe?

By GyroscopeUpdated November 14, 20266 sources

For most healthy people, yes. See a doctor first if exercise brings chest pain, fainting or unusual breathlessness, or you have heart, metabolic or kidney disease. If you’ve been inactive, build up with lighter exercise before an all-out test.

A VO2 max test asks you to go until you can’t, which sounds like exactly what a heart shouldn’t be asked to do. The US sports medicine rules for who should see a doctor before exercise were rewritten in 2015 because the old ones sent too many healthy people to the doctor, which may have put them off exercising. The panel noted that exercise is safe for most people, and that the risk falls as people get fitter.

We’d start with a walk test if you’re unsure, since it never asks for an all-out effort, and save the max tests for when you’ve built up to hard sessions.

Who should see a doctor first

The American College of Sports Medicine’s screening rests on three things.

1. How active you are now. Someone already exercising regularly is at lower risk than someone starting from the couch.
2. Signs or symptoms, or known heart, metabolic or kidney disease. Chest pain or pressure, fainting, or unusual breathlessness during exercise, or a diagnosis like heart disease, diabetes or kidney disease, means a doctor’s clearance first.
3. How hard you plan to go. A max test is the hardest effort there is.

Risk factors on their own, like age or high cholesterol, no longer trigger a doctor visit by themselves. The panel also noted that heart events during exercise are often preceded by warning signs, which is why the symptoms come first.

Lab tests

Commercial labs screen before booking. Superpower requires a health and safety form and a physician’s authorization before it confirms an appointment, and Quest calls the Fitnescity test it sells highly strenuous, a maximal exertion test. A test your doctor orders, for symptoms or a heart or lung condition, is done with medical monitoring.

Field tests at home

The 1-mile walk test, built on 343 adults aged 30 to 69, asks you to walk as fast as you can, with no running, which makes it the gentle choice if you’re older or out of practice. The 12-minute run, the 1.5-mile run and the beep test are all-out efforts, and they suit people who already run. Building up is like a car’s first drive after months in the garage, where you ease into speed before you open it up.

Age alone doesn’t rule out hard sessions. In Generation 100, 400 people aged 70 to 77 did supervised 4x4 intervals twice a week for five years, and the researchers concluded that long-term intervals were feasible and safe for older adults.

When to stop

Stop and get help if you feel chest pain or discomfort, feel weak, light-headed or faint, have pain in your jaw, neck, back, arms or shoulders, or get short of breath out of proportion to the effort. Those are the CDC’s heart attack warning signs, and the CDC says to call 911 right away.

If you’re pregnant, skip max tests and ask your doctor or midwife what’s right for you. On a beta blocker, see heart rate zones on a beta blocker.