For years, the longevity conversation has been about two numbers. Lifespan is how long you live. Healthspan is how many of those years you spend free of serious disease. A new idea asks a sharper question: for how long are you actually at your best?

That window is called peakspan. It is the age range in which you keep at least 90% of your peak performance in a given area, such as heart and lung fitness, muscle strength or thinking speed. You can be perfectly healthy at 50 and still be well past your peak, which is why many researchers now see peakspan as the metric that really matters.

The research behind peakspan

The term comes from a paper by longevity researchers Alex Zhavoronkov (CEO of Insilico Medicine) and Dominika Wilczok, titled Peakspan: Defining, Quantifying and Extending the Boundaries of Peak Productive Lifespan. It first appeared as a preprint in December 2025 and was published in the journal Aging and Disease in 2026.

The authors argue that healthspan misses something important: the steady loss of capacity that happens even when you are not sick. Pulling together data across many body systems, they found that most of them peak in early adulthood. As a result, most adults spend the bulk of their lives in what the paper calls a "healthy but declined" state.

One caution: the paper is a synthesis of existing studies, many of them cross-sectional, rather than a single long-term study following the same people. The 90% threshold is a proposed definition, not a medical standard.

How to stretch your peakspan

The good news is that ageing is uneven, and the pace differs a lot between people. A 2025 Nature Medicine study of blood proteins from nearly 45,000 people found that people born in the same year can differ in biological age by up to 15 years, as Dr Stacy Sims notes. Here is where to focus:

1. Train your heart and lungs hard, not just often. VO2 max falls fastest after 40. Dr Rhonda Patrick points out that about 40% of people who meet standard moderate-exercise targets do not improve their fitness without adding high-intensity work.
2. Lift weights. Muscle strength plateaus through midlife and then drops steeply at 60–70. Building strength earlier gives you more to keep.
3. Protect your bones, especially around menopause. Women lose bone faster as estrogen falls, so strength and impact training matter more from the 40s.
4. Keep your mind working. Knowledge and experience usually hold until about 80, so keep learning new, demanding skills.
5. Measure, don't guess. The peakspan framework suggests tracking VO2 max, grip strength, processing speed and heart rate variability, so you can see decline early and act on it.

The Takeaway

Peakspan reframes the goal of ageing well. It is not only about avoiding disease, but about staying close to your best for as long as possible. Most of us will be past our physical peak by our 30s, but how steeply we decline after that is partly in our hands.

Medical Disclaimer: The information and reference materials contained here are intended solely for the general information of the reader. One should consult a qualified trainer and your physician for advice and before beginning a new diet, nutritional or fitness program. The publisher or its management do not claim responsibility of this information.