Related Experiment Video
Updated: Mar 27, 2026
Assessment of Physical Activity Intensity with Accelerometers and Oxygen Consumption
Published on: June 20, 2025
The descriptive epidemiology of accelerometer-measured physical activity in older adults
K Berkemeyer1, K Wijndaele2, T White3
1MRC Epidemiology Unit, University of Cambridge, School of Clinical Medicine, Box 285 Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK. katrin.berkemeyer@mrc-epid.cam.ac.uk.
Background:
Objectively measured physical activity between older individuals and between populations has been poorly described. We aimed to describe and compare the variation in accelerometry data in older UK (EPIC-Norfolk) and American (NHANES) adults.
Methods:
Physical activity was measured by uniaxial accelerometry in 4,052 UK (49-91 years) and 3459 US older adults (49-85 years). We summarized physical activity as volume (average counts/minute), its underlying intensity distribution, and as time spent <100counts/minute, ≥809counts/minute and ≥2020counts/minute both for total activity and that undertaken in ≥10-min bouts.
Results:
In EPIC-Norfolk 65% of wear-time was spent at <100 counts/minute and 20% spent in the range 100-500 counts/minute. Only 4.1% of this cohort accumulated more than 30 min/day of activity above 2020 counts/minute in 10-min bouts. If a cut-point of >809 counts/minute is used 18.7% of people reached the 30 min/day threshold. By comparison, 2.5% and 9.5% of American older adults accumulated activity at these levels, respectively.
Conclusion:
As assessed by objectively measured physical activity, the majority of older adults in this UK study did not meet current activity guidelines. Older adults in the UK were more active overall, but also spent more time being sedentary than US adults.
