Medical Specialty >> Cardiology

Doctors Lounge - Cardiology Answers

Back to Cardiology Answers List

If you think you may have a medical emergency, call your doctor or 911 immediately. Doctors Lounge ( does not recommend or endorse any specific tests, physicians, products, procedures, opinions, or other information that may be mentioned on the Site. 

DISCLAIMER: The information provided on is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her physician. Please read our 'Terms and Conditions of Use' carefully before using this site.

Date of last update: 10/20/2017.

Forum Name: Miscellaneous Cardiology Topics

Question: Marathon Training

 jaobryan - Sun Sep 09, 2007 5:11 pm

I am a 39 year old woman and have been training for the Chicago Marathon. Recently, I have been trying to pass out. I get dizzy, feel faint, heart racing, hands numb and get shaky. I have not passed out yet, but sometimes I come very close. I also have noticed that when I get this way, I feel as if the blood has completely drained from my head. I had a physical prior to beginning to train and everything was perfect. No cholestrol problems, bp was fine, no heart problems and was not overwieght. I am in perfect health. I have lost about 15 pounds in the process but am still at a very healthy weight. Could this be low blood sugar, overtraining, fatigue or anxiety due to the impending race? Thanks for the advise.
 Dr. Chan Lowe - Sun Sep 09, 2007 8:50 pm

User avatar Hi Jaobryan,

Low blood sugar, anxiety, and fatigue can all cause episodes of fainting feelings. I would recommend you see your doctor for an evaluation to be sure nothing dangerous is going on.

Best wishes.

| Check a doctor's response to similar questions

Are you a Doctor, Pharmacist, PA or a Nurse?

Join the Doctors Lounge online medical community

  • Editorial activities: Publish, peer review, edit online articles.

  • Ask a Doctor Teams: Respond to patient questions and discuss challenging presentations with other members.

Doctors Lounge Membership Application

Tools & Services: Follow DoctorsLounge on Twitter Follow us on Twitter | RSS News | Newsletter | Contact us