Although twitchy eyes or blurred vision while jogging could be caused by something as simple as particles flying into your eyes or allergies, eye problems during exercise can be symptomatic of a more serious problem. Talk to your doctor before beginning a physical activity program if you have a bleeding or detached retina, or have had eye surgery or laser treatment; strenuous activity can aggravate these conditions.
Low Blood Pressure and Dehydration
Blurred vision is one symptom of a drop in blood pressure. During strenuous exercise, dangerously low blood pressure and accompanying vision problems may be associated with dehydration. When jogging, be sure to drink plenty of water, especially if you're outdoors on a hot day. Stop, drink water and get indoors if possible if you experience blurred vision, nausea, confusion, dizziness or confusion. Seek medical attention if you don't recover right away.
Pregnancy
If you're pregnant, you can usually continue much of your normal exercise routine -- even jogging -- into your second trimester. However, vision problems during exercise can indicate something serious during pregnancy. Blurred vision is again a sign of dehydration, which can prevent enough blood from getting to your fetus' developing organs. It can also be a sign of preeclampsia, which restricts the flow of blood to the placenta. Stop jogging and call your doctor immediately if you experience vision problems during jogging while pregnant.
Concussion
If you run into something while jogging and hit your head, take a moment to evaluate your condition before restarting your run. Blurred vision, dizziness, "seeing stars" and sensitivity to light after a blow to the head can signal a concussion. You don't have to lose consciousness to experience a concussion; many people feel fine right away after the head trauma, but symptoms can manifest themselves over the next few hours or days. See a doctor if you don't feel right after a head injury, and steer clear of exercise until you get a doctor's OK if you've suffered a concussion.
Glaucoma
Glaucoma is an eye condition that causes progressive vision loss if untreated. There are several types of glaucoma; one variety, pigmentary glaucoma, is associated with pain and blurry vision after exercise. White males in their mid-30s to mid-40s are the group most likely to experience this type of glaucoma. Blurry vision can also occur with acute angle-closure glaucoma, though not necessarily in conjunction with exercise. If you experience blurred vision and eye pain on a regular basis, see a doctor to get tested for glaucoma.
