Visual Impairment After Long, Cold Marathon Swims

Courtesy of Pat Gallant-Charette, Westbrook, Maine.

If there is anyone who knows how to multitask, it is Pat Gallant-Charette.

The retired American nurse from Maine watches her grandchildren and trains for her numerous marathon swims while following trackers of marathon and channel swimmers worldwide. “I love our sport,” says the International Marathon Swimming Hall of Fame Honor Swimmer.

She spoke about one unusual post-swim phenomenon, “[My recent] Lake Memphremagog [crossing of 24 hours 8 minutes] was a beast. It is among my top five challenging swims.

Over the past few years, I have noticed some very strange post-swim side effects. I will have the typical wobbly legs for a short period of time, then my thought process is clouded for a few hours post-swim. But the strangest post-swim side effect is my vision.

After my Lake Memphremagog swim, my vision was greatly affected. If I looked at some roadside shrubs, one moment later I would look at the center of the road and those shrubs would be in the center of the road – the identical scene that I looked at moments before.

I knew there were no shrubs in the middle of the road, but that’s what I see. It is like my brain took a snapshot of a scene and within 10 seconds I would see the same scene when I turned my head away to look at something else. Then [the scene] would disappear.

I asked my eye doctor if this is caused by ocular pressure and she thought it was something related to a neurological effect. Thank heavens this phenomenon last only about an hour
.”

She understands that this temporary visual disturbance is a very bizarre phenomenon and is greatly relieved that it clears within one hour post swim. She explains further, “It has happened only with marathon swims of over 16 hours in cold water (like in the North Channel) and warm water (like in Lake Memphremagog). As a nurse, I am very intrigued by this adverse post-swim effect.”

Her grandson Trevor came up with a plausible theory. “He believes that my temporary adverse vision problem is due to poor visual perception. He explained that as a swimmer, I was looking down into dark water, then as I turned my head to breath, I would see an image. That repeated pattern for 24 hours may have led to my visual disturbance. He believes that after 24 hours of swimming, I developed a temporary visual perception impairment.

Trevor is only 11 years old, but he has plans of attending MIT. He is very well read and he may have a point on his interpretation
.”

If other swimmers have experienced visual disturbances for short periods after their post-marathon swims, it would be great to start collecting this information and ask medical professionals if Trevor’s theory is correct,” says Steven Munatones. “While Pat experiences this after her swims over 16 hours in both cold water and warm water swims, it would be great to start documenting other experiences from other swimmers around the world.”

Swimmers can send information to headcoach@openwatersource.com if they wish to contribute to this issue.

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