Research

Energy balance

Physical activity levels (measured by PAL and activity monitors) remain stable between young adulthood (20-34 years) and middle age (60-74 years), with a significant decline only occurring in nonagenarians (90+ years).

You do not need to accept a gradual decline in activity as you move from your 20s to your 60s. This research shows that physical activity levels can be maintained throughout middle age. The significant drop in activity only occurs in the 90s. Focus on maintaining your current activity habits, as the biological drive to move does not necessarily fade until very late in life.

GoodQualifiesHIGH confidence
Interestingly, PA was similar between young volunteers and those who were in their 60s and 70s... PA was markedly lower in nonagenarians compared with young and aged adults.
Darcy L. Johannsen et al. · Journal of Applied Physiology · 2008

Why this rating

Large sample size (n=206), objective measurement methods (Doubly Labeled Water, accelerometry), and rigorous statistical adjustment for body composition.

Source

Physical activity in aging: Comparison among young, aged, and nonagenarian individuals

Darcy L. Johannsen et al. · Journal of Applied Physiology · 2008

DOI 10.1152/japplphysiol.90450.2008

cross_sectional · n=206Cited 79×
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DOI resolved against Crossref · corpus check 2026-06-10

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