Extensive biking lead to passing out or something?

Question

I started biking everyday starting last week and have been riding my bike daily since. Today I went on a bike ride for about 3 miles and didn't stop riding, I went non-stop with no breaks in between. I got home after riding those 3 miles and parked my bike in the garage like normal. When I got off my bike my vision went blackish and everything that I could see got blurry. I felt like I was going to vomit and just felt really overworked. Is this normal for a extensive workout? I weigh 138 lbs. and im 5'5. I've just really been trying to loose weight because I had a baby almost 2 years ago. Any advise??? This was just really creepy. I felt like I was going to pass out or something. Very scary. Thanks!!!

Answer 1

First of all, are you in good health?  Have you had a physical recently?

If the answer to either of these is: no, I'd go see a doctor sooner rather tthan later.

Otherwise, there are usually 3 things that contribute to this type of episode.  Heat, dehydration and low blood sugar.  

Heat and dehydration can go hand in hand.  However, it is quite possible to get dehydrated in cool temperatures.  Also, it is quite possible to get overheated while fully hydrated especially during periods of high humidity.

Overheating can be avoided by riding during the cool parts of the day, avoiding dehydration, and wearing light colored clothing.  Your body will gradually acclimate to high temperatures, but you need to give it some time.

To avoid dehydration you need to start the ride fully hydrated and plan to drink about 1 bottle of water per hour.  The best signal of dehydration is yellow urine.  If you drink enough to keep your urine clear you should be in good shape.  Remember, overhydration is dangerous, as well.  If you are drinking enough water to feel bloated, naseous, have swollen fingers and puffy skin, you are overhydrating.

If you didn't get too hot and you weren't dehydrated, I suspect you had low blood sugar.  Low blood sugar will cause tunnel vision, nausea, disorientation, lack of coordination, head ache, etc.  If you are simultaneously attempting to diet and increase your exertion level, you may simply have run out of stored glucose.  Cyclists call low blood sugar "the bonk" and it absolutely sucks.  Fortunately, it is very easy to deal with: eat something sugary like an energy gel, banana, cookie, etc.  When dieting to lose weight, most cycling coaches recommend you eat a bit prior to a ride so you have enough glucose to get you through the ride.  Don't overdo it, though, a few hundred calories will easily get you through an hour ride.

Hope this helps.

Answer 2

3 miles shouldn't cause dehydration. Since you say you have been riding everyday for the past week, your body probably needs a day off. There could be a number of things causing this,however.

   When I first started getting back into riding a couple of years ago, I had a similar experience. I think I pushed myself too hard and too quickly. Also, the type of bike you are using could be part of the problem. I originally made the mistake of buying a cheap bike from Target and it weighed over 55 lbs.  I decided to invest a few hundred into a good bike and the difference was night and day. Never had the dry heaves from riding since. Overall, my bike riding experience has been great and I've lost over 60lbs. because of it.

What type of Bike do you have and what type of riding do you do? Send me an email or IM.

Answer 3

It sounds like dehydration to me.. Keep water up drink as much as u can through the rides and after. Had u eaten cause sometimes not eating for a certain amount of time can make u abit nausous...

But i'd say u were just very dehydrated hun.. Good luck :-)  

Answer 4

Were you over heated ? 3 miles is not that far, you want to gradually increase your distance and effort so your body has time to recover.  Be sure to carry water with you.

Answer 5

I had that exact same situation happen to me when I was about 17 years old.....fast ride in city traffic in the heat of summer.  My ride was about 12 miles and when I walked into the bike shop....tunnel vision and stars and nausea within a minute or so of getting off of the bike.  It went away in a few minutes and I didn't puke.  lol.  

Provided that you don't have any other health issues going on, it was probably just that you were overtaxing your circulatory system for your current level of fitness.  Dehydration, as the others already said, can play a huge part in that.  Two other times in my life I got close to the same feeling and I'm sure hydration played a part in those rides.

So as long as you're otherwise healthy, just be sure to stay hydrated before, during, and after your exercise (and at night!) and you should be fine.  As you ride more and get more fit, you shouldn't see those problems anymore.  If it ever does happen again, though, be sure to sit down, just in case you do pass out.  And as always, it never hurts to visit with your family doc to ask questions and get his opinion.   Also, one thing that can help prevent it from happening is to taper down your workout for a few minutes, gradually letting your pulse slow down before you stop.  You may still feel a little odd, but letting your body adjust slowly sure helps a lot.   :o)

Answer 6

I will add a vote for hydration and nutrition, with the disclaimer that 3 miles before a near pass out is not normal.

It might be as simple as nutrition/water, but it could be any number of health related issues from a flu bug to cardiac disease.

I don't mean to be an alarmist, but 4 years ago my athletic cousin passed out after playing basketball for an hour with his friends.  By the time the paramedics got him to the hospital he was gone.

A doctor hooking him up to an EKG would have noticed his abnormal heart rhythm and done something about it.  He was 34 years old, 6ft tall, thin, fit, had a good job and family.  His heart was a ticking time bomb.  He played basketball all the time, exercised, ran...but never had talked with his doctor about his occasional lightheaded episodes.