More and more research confirms the health benefits of regular exercise. Now a a new study published in The Journal of Neuroscience suggests that moderate aerobic exercise may slow the progression of diseases that destroy the retina of the eye and eventually cause blindness.
Age-related macular degeneration (AMD) results in a loss of vision in the center of the visual field of the eye because of damage to the retina and is the leading cause of severe vision loss and blindness in individuals over the age of 60. According to the American Academy of Ophthalmology, more than 2 million over the age of 50 in the United States suffer from advanced AMD.
Previous research has suggested that exercise may slow the progression of AMD, possibly by stimulating a protein called brain-derived neurotrophic factor (BDNF) that helps brain cells grow and remain healthy. Similarly, yoga is known to help with a lot of diseases and health conditions if practised consistently.
Yoga is a method that naturally helps with physical and neurological ailments, and each yoga asana can be practised according to the needs of the person without much risk. Neurological repair in the body is a complicated process but many with eye problems tend to see better results by practising yoga like Surya Namaskar, Padhasthasana, and downward facing dog among other types of asanas regularly. In both cases of excercise and yoga, increased blood circulation seems to improve the results.
In the present study, researchers led by Dr. Machelle Pardue of the Atlanta VA Center for Visual and Neurocognitive Rehabilitation and Emory University investigated the effect of aerobic exercise on retinal cells experiencing degeneration using a rodent model.
The researchers studied two groups of mice: an exercise group and a non-exercise group. The exercise group ran on treadmills for an hour a day for five days per week for two weeks.
After two weeks of exercise or non-exercise, the researchers exposed half of each group of mice to very bright lights or dim lights for four hours. The bright lights were bright enough to damage the retinas of the eyes.
Exposure to the very bright lights caused a 75 percent loss of both retinal function and photoreceptor numbers. However, the mice in the exercise group who were exposed to the bright light had two times greater retinal function and photoreceptor nuclei than the exposed mice in the non-exercise group. The mice in the exercise group also had 20 percent higher levels of BDNF protein than the mice in the non-exercise group.
When the researchers then injected the mice with a drug that blocked the BDNF protein, the researchers found reduced retinal function and photoreceptor counts in the mice in the exercise group similar to the mice in the non-exercise group.
The researchers conclude that “aerobic exercise is neuroprotective for retinal degeneration and that this effect is mediated by BDNF signaling.”
Comments Dr. Pardue on the findings, “This is the first report of simple exercise having a direct effect on retinal health and vision. This research may one day lead to tailored exercise regimens or combination therapies in treatments of blinding diseases.”
Another recent study concluded that moderate exercise could decrease the risk of stroke in women by 20 percent and could offset the increased risk in women taking postmenopausal hormone therapy.
References
Aerobic Exercise Protects Retinal Function and Structure from Light-Induced Retinal Degeneration: http://www.jneurosci.org/content/34/7/2406.short
Exercise May Slow Diseases That Cause Blindness: http://www.medicalnewstoday.com/articles/272840.php
Exercise May Slow Progression of Retinal Degeneration: http://www.sfn.org/Press-Room/News-Release-Archives/2014/Retinal-Degeneration
Image Credits
Young Woman Doing Pushups: http://www.freeimages.com/photo/1419880
