Abstract
Abstract: :
Purpose: Current treatments for dry eye conditions provide temporary symptomatic relief, often in the form of tear substitutes. Although research evidence is lacking, anecdotal evidence suggests that aerobic exercise may increase tear volume. This pilot study was designed to determine the effect of physical activity on aqueous tear volume. Methods: Schirmer wetting (mm/5 min) from university students (n=11) without dry eye conditions was determined on two different days; (Day 1) at rest (no physical activity previous 12 hours) and (Day 2) 5 minutes after a treadmill VO2 max test. Data were analyzed with 2 x 2 mixed (Gender x Pretest - Posttest) ANOVAs with repeated measures on the last factor. Results: As a group, there was no significant difference in Schirmer wetting between resting and post-exercise states. However, when analyzed by gender, physical exertion produced opposing effects on Schirmer values. Schirmer wetting (mean SD) tended to increase with exercise for females (n=6: left eye resting 21.4 2.0, post exercise 25.4 1.5: right eye resting 21.6 1.3, post exercise 24.8 2.9). In contrast, Schirmer wetting for males (n=5) tended to decrease (left eye resting 18.3 3.6, post exercise 17.0 3.4: right eye resting 17.8 2.7, post exercise 16.5 3.1). Statistical analysis revealed a significant interaction for the left eye F(1,9) = 6.39, p = .03. However, in this preliminary study, the interaction for the right eye failed to reach significance (p = .20). Conclusion: These data suggest that physical activity may alter tear volume in a gender specific manner and indicate that this line of research should be pursued.
Keywords: 376 cornea: tears/tear film/dry eye • 452 lacrimal gland