donating blood & exercise

I donated blood today at noon, and I'm not sure about exercising this evening.  I didn't think to ask the nurses running the blood drive, and when I went on line to the Red Cross and other websites, I got conflicting information.  I read everything from "wait 5 hours" to "wait 12-24 hours", and "mild exercise should be alright, just no weight training or extremely strenuous exercise".  I don't know what information is accurate.  I assume everyone's body reacts differently, but I was wondering if anyone has experience with this.  I really don't want to skip my workout tonight, but I don't want to pass out on the side of the road during my run either.

Unfortunately, I'd advise you to skip your workout today.  You should drink lots of fluids today to raise your blood volume to normal; that takes some time.  If you exercise while your blood volume is temporarily low, you could experience dangerous fluctuations in blood pressure; you could become dizzy or even faint. 

Good on you for donating blood, though!  I used to be the chairperson of the blood drives at my old workplace and it's great when folks donate.  You are saving lives!

Thanks so much!  Even though I was kind of hoping to hear otherwise, I appreciate the information.  I can just workout a little harder and longer tomorrow, and eat a lighter supper tonight. 

Thanks again!

Glad you are going to skip the after-donation workout!

For future reference, I've had good luck working out a few hours before donating blood and was also able to work out the next day.

Yeah, I would definitely skip your work out for today! :-)

Thanks for the feedback everyone.  In the future, I will definitely plan my workout prior to giving blood.