Breathing technique protects retina in short-sighted bodybuilders
Weight lifters that are short sighted should pay extra attention to their breathing technique. As blood pressure rises during training it can lead to a torn retina in the eye, epidemiologists at the University of Bologna in Italy discovered.
If your retina becomes detached you can turn blind. It was already known that short-sighted people are more likely to tear their retina. The Italians set up their study to see whether there were other risk factors involved for short-sighted people.
The researchers gathered data in Italian hospitals on sixty patients with detached retinas, and noted the patients' other particulars. They also did the same for one hundred short-sighted Italians who did not have a detached retina. They then compared the data from the two groups.
From their reading of the literature, the researchers had already worked out that people who are physically active are more likely to incur retina damage. If they hold their breath, even lifting a paltry weight of fifteen kilos can cause the blood pressure in the eye to increase by 23 mm Hg. Makes you wonder what happens to the blood pressure in the eyes of serious weightlifters...
The most important risk factors that the Italians found are listed below.
As you can see, short-sighted people with a BMI of over 25 are seven times more likely to tear their retina. The researchers suspect that a high BMI increases the blood pressure in the eye.
Another factor is lifting weights. Say the chance that someone who never lifts weights damages their retina is 1, then the chance of people who lift light weights incurring damage does not rise. The researchers didn't only take into account how much weight someone lifts, but also the number of reps and how many years they have been doing so. But for short-sighted people who lift heavy weights, the likelihood of a torn retina is four times greater. That's a lot but the overweight factor weighs more heavily.
The researchers are also planning to study the effect of weightlifting on people who do not have sight problems.
The take home message of the study is clear. Weight trainers, and certainly bodybuilders, should pay attention to their breathing technique. During intensive reps it's better not to hold your breath because this causes blood pressure to rise further.
Epidemiology. 2008 Nov;19(6):868-71.