Moderate-to-vigorous walking or other types of physical activity may improve retinal health, according to a large population study using a national database from the United Kingdom.

Researchers found people who exercised more intensely appeared to gain more protection against retinal thinning, a hallmark of age-related macular degeneration (AMD). "We saw a very clear dose-dependent relationship where an increased quartile of moderate to vigorous physical activity was associated with thicker outer retinal layers," Anika Kumar, MD, an ophthalmology resident at the University of California, San Francisco, told Medscape Medical News. Kumar presented the findings at the American Academy of Ophthalmology (AAO) 2026 Annual Meeting in New Orleans.

Study Design and Results 

The study included data from 11,165 adults in the UK Biobank who had had an optical coherence tomography (OCT) scan to evaluate retinal structure and wore an accelerometer for 7 days to track their physical activity. The definition of moderate-to-vigorous physical exercise included activities such as brisk walking and walking while carrying objects, Kumar said. 

"When we categorize those people into four groups based on the time that they spent in moderate to vigorous physical activity, we saw that in the groups with higher moderate to vigorous physical activity, they were found to be associated with thicker outer retinal layers," she said. "And we saw this in the photoreceptor inner segment and outer segment. We also saw this in the outer nuclear and outer plexiform layers and the central macular subfield thickness."

The study found greater moderate or vigorous physical activity was linked to increased thickness in the respective retinal layers. Each of the three highest-activity groups compared with the next lower group had an increase in the retinal layers according to the following measures: 0.35 µ in the outer nuclear and plexiform layers; 0.06 µ in the photoreceptor inner segment layers; 0.15 µ in the photoreceptor outer segment layers; and 0.85 µ in macular central subfields (P < .02). Greater physical activity was also associated with a 24% lower odds of AMD from the lower to the next highest group (odds ratio, 0.77; P = .005).

"There were clear dose-dependent relationships that were all significant even after adjusting for age, sex, BMI, refraction, hypertension, and diabetes," Kumar said. 

A limitation of the study was its cross-sectional design, Kumar acknowledged, that captured a snapshot of retinal structure based on OCT at one point in time. 

"We were definitely not able to establish temporality of our associations, but the associations were there," she said. "I think this supports the idea that the retina can potentially be a way to understand more about someone's systemic health and it could potentially be something that clinicians can counsel patients about in regarding to the link between physical activity and age-related macular degeneration."

Also, while the study population was large and from a large United Kingdom database, the population may not have been "the most representative," Kumar added.

Strengths, Limitations, and Future Directions 

Strengths of the study she noted were the underlying large population, the capture of retinal imaging with OCT, and the use of accelerometry to objectively capture data on participants' physical activity levels. 

Future studies looking for a link between physical activity and AMD should evaluate OCT images at multiple timepoints, Kumar said. 

"Another direction we can take from the study is to try to understand more about this relationship mechanistically," she said. That would include further exploration of vascular and inflammatory mechanisms, she said.

More data would be needed to clarify a dose-response relationship between physical activity and AMD, Dagfinn Aune, PhD, MSc, a research fellow at Imperial College London who has studied physical activity and disease risk in cataract and AMD, told Medscape. 

"Previous studies on physical activity and AMD risk have not been fully consistent," he said. His group's recent meta-analysis found a potential benefit of physical activity on AMD risk, but the finding was not statistically significant, Aune noted.

"The novelty in this study is that they have looked more in depth at potential mechanisms that could explain a reduced risk of AMD with higher physical activity by looking at how physical activity is associated with retinal structure," he said of Kumar's analysis. "The findings suggest physical activity could reduce AMD risk through changes in the retina."

He added that further prospective cohort studies would be needed to clarify the associations between physical activity and retinal structure "to establish a temporal relation." 

Kumar and Aune reported no relevant financial conflicts of interest. 

Richard Mark Kirkner is a medical journalist based in the Philadelphia area.