Ask The Doctor > Questions & Answers > I am a 52 year old male, very fit and healthy.

I am a 52 year old male, very fit and healthy.

Patient: I am a 52 year old male, very fit and healthy.I’ve recently been having some strange experiences whilst running which have now been occurring more frequently.I’m currently competing in and training for half Iron Man Triathlons so am running @ 40-50kms/wk.What has been happening is I start the run, everything is fine and then when I get to @the 3km mark I get this strange feeling in my head. It’s not quite dizziness but probably best described as really light headed. It also feels a bit like my vision goes into stop motion where each foot strike it feels like my vision skips a frame.I’ve been doing aerobic based training at the moment so not pushing the heart rate on these training runs. I monitor my heart rate throughout the run and everything is normal. I don’t feel tired or fatigued when this happens, just really weird and uncomfortable.When I continue on for another couple of km’s, the feeling goes and the rest of the run is good.It’s happened on and off over the years but generally only a couple of times a year. Now it seems to be happening every second run or so.I don’t notice this whilst doing the swimming training or cycling.I generally run in the morning after a good breakfast (with enough time to digest).Your thoughts would be appreciated.Kind regardsMike



Symptoms: Light headed/dizzy during running
Very slight numbness in both hands
Vision skips a frame with each stride
Goes away when continuing to run



Doctor: Hi MIke. So, it seems like your body is trying to gather more energy at around the 3km mark which is when the active car bohydrates are exhausted and your liver provides stored energy. Light headedness and visual blurring while running may be related to one or more of the following factors1. Low Sugar level2. Inadequate pumping of blood by the heart3. Decreased ability of the body to increase heart rate and blood flow in accordance with the exercise4. Inadequate reserves in the liverI suggest the following1. Check your fasting and post prandial sugar level2. Do an EKG3. Do liver function tests – Total bilirubin, SGOT/SGPT/GGT4. Stop consuming alcohol if you doIf these tests are normal and you still have these episodes of light headedness, you will need to consult a specialist for more elaborate testshope this helps

Comments / Follow Ups

Patient: Thanks for the information. I do enjoy a glass of red wine so I will cut that back (only have a glass or two and this doesn’t seem to correlate to the issues). I’ll go and see my local GP for some tests.

Doctor: A glass or two of red wine should not be an issue. Take care, Bye


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Dr. Suneel Sharman M.D.

Dr. Suneel Sharman M.D.

Dr. Suneel Sharman completed his residency in Family Medicine at the University of Toronto. He currently operates Infinity Health Centre, a walk-in-clinic in downtown Toronto.

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