Recently, eye care practitioners have begun to investigate the effects of physical exercise on ocular health, and subsequent research has suggested resistance exercise may induce abrupt intraocular pressure (IOP) changes. A new study in Optometry & Vision Science looked into this association and found four different isometric resistance exercises led to an instantaneous and progressive IOP rise, and these changes were independent from the exercise type.

The study enrolled 28 physically active college students who performed two minutes of isometric exercise including military press, biceps curls, leg extensions and calf raises against two different loads (high load and low load).

The researchers measured IOP with rebound tonometry before, during (semi-continuous assessment, 24 measurements), and after 10 seconds of recovery in each of the eight conditions.

The investigators reported a statistically significant load effect, with greater IOP when the individuals performed isometric exercises against heavier loads. Additionally, the researchers noted a positive IOP rise during the execution of isometric exercise in the high-load condition. After exercise, IOP rapidly retuned to baseline levels within 10 seconds. The study found an instantaneous and progressive IOP rise during the execution of isometric exercise leading to muscular failure, regardless of the exercise type and participant’s sex.

As such, IOP assessment during exercise should be recommended, the investigators said.

“The outcomes of this study may have important implications for the management of ocular conditions in which maintaining stable IOP levels is desirable, especially for subjects at high risk of glaucoma onset or progression,” the researchers wrote in their paper.

They also noted they would include glaucoma patients in future studies.

Vera J, Redondo B, Koulieris GA, et al. Intraocular pressure responses to four different isometric exercises in men and women. Optom Vis Sci. April 2020. [Epub ahead of print].