Sources

• Fitness by age and sex. Leonard A. Kaminsky, Ross Arena, Jonathan Myers, “Reference Standards for Cardiorespiratory Fitness Measured With Cardiopulmonary Exercise Testing: Data From the Fitness Registry and the Importance of Exercise National Database,” Mayo Clinic Proceedings 90, no. 11 (2015): 1515–1523, doi:10.1016/j.mayocp.2015.07.026; open text at PMC4919021 (fetched 8 Oct 2026). Table 2, the measured treadmill VO₂max percentiles from FRIEND (4,611 men and 3,172 women, apparently healthy, 20–79). The registry published an update in 2022 (Kaminsky et al., Mayo Clin Proc 97(2):285–293) that adds the 80–89 decade and runs 1.5–4.6 mL/kg/min lower on treadmills; it is behind a paywall, so it is not used here, and this chart probably flatters every age a little.
• What activities cost. Stephen D. Herrmann et al., “2024 Adult Compendium of Physical Activities: A third update of the energy costs of human activities,” Journal of Sport and Health Science 13, no. 1 (2024): 6–12, doi:10.1016/j.jshs.2023.10.010; values from pacompendium.com (fetched 8 Oct 2026), checked against the Compendium’s 2024 PDF. Each MET is converted at the Compendium’s own standard, 1 MET = 3.5 mL/kg/min:

  Code	Compendium activity	METs	mL/kg/min

• Mortality. Kyle Mandsager, Serge Harb, Paul Cremer, Dermot Phelan, Steven E. Nissen, Wael Jaber, “Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing,” JAMA Network Open 1, no. 6 (2018): e183605, doi:10.1001/jamanetworkopen.2018.3605; PMC6324439. Hazard ratios from the text and Figure 2C. Groups are percentiles of that clinic’s own patients, in treadmill METs estimated from the test, not measured VO₂max.
• The idea. Peter Attia with Bill Gifford, Outlive: The Science and Art of Longevity (New York: Harmony Books, 2023), on VO₂ max, its decline with age, and the centenarian decathlon.

Method

The registry gives seven percentiles for each decade. Each is plotted at the decade’s midpoint (25, 35 … 75) and joined with straight lines; the dots are the published values. Your position is placed between the two percentile lines around it, in proportion, and carried forward at that same position: “if I stay at the 50th percentile for my age”. The norms are cross-sectional: different people in each decade, not the same people followed over time, so this is what staying at your rank looks like, not a forecast of how any one body ages. Above the 95th or below the 5th percentile, your line keeps the same ratio to the nearest edge line, which is an assumption, not data.

An activity line is the typical oxygen cost of doing it, from the Compendium. Reaching it means working at your maximum; nobody can hold their maximum for long, so in practice you need headroom above a line to do that activity comfortably or for more than a few minutes. The chart does not put a number on that margin, because the sources here don’t. Compendium METs are averages; the 2024 Adult Compendium covers ages 19–59 (a separate Older Adult Compendium, not used here, covers 60 and over), and the same task can cost a given person more or less.

This page illustrates published averages and arithmetic on them; it is not medical advice. Talk to a doctor before starting hard exercise, especially if you have heart disease or symptoms, or haven’t trained in a while.

Changelog

• 8 Oct 2026Restyled in the site's shared look: white, Helvetica, plain titles.
• 8 Oct 2026First published, with FRIEND 2015 percentiles, twelve Compendium activities, and the Mandsager hazard ratios.