I was feeling great before a group ride this morning. I went really hard up a hill and at the top there is a gas station. We all stopped there. As soon as I got off my bike I got really hot and my heart was beating hard and slow. I felt dizzy and blacked out for a second. I sat for a couple of minutes then rode back and felt fine all the way back. I was wondering if the reason i blacked out was because i did not cool down before dismounting my bike. Is this a reasonable explanation? I feel fine now.

It could be a number of things. It's not something that should be taken lightly though.

See a doctor.

HEAD RUSH! I get those all the time. Its no biggie, at least I think. I am also 16 years old. if you are at risk for a heart attack or stroke, I'd get it checked out, but otherwise, I wouldn't worry about it...

You also might have been dehyraded, you could have bonked...a number of reasons could have caused your "blackout"

I don't think it was dehydration cause we were only 30 minutes into the ride and my piss when i got home was clear. I am 20 by the way so i don't think stroke or heart attack is a strong factor. I do get head rushes sometimes at home when getting up from the couch real fast which causes me to be dizzy. Probably that. Also later today i did a 30 minute TT do determine my LTHR and felt great before during and after, so I believe I just got off to quick without cooling down.

Most likely it was low blood pressure after the climb. This happens from time to time to different people. The reason I say get it checked out is because it can be an indication of heart problems, something you don't want to mess around with.

Sounds like hyperventillation.

If you blacked out go see a doctor it could be any of a number of things and probably won't be anything bad. But just in case have yourself checked out anyway.

Blood glycogen levels are low in the morning usually. You may want to be sure you're getting enough rest and getting some calories in the morning before those rides.

" Black-outs " are not normal. See your doctor and get checked out. Better safe than sorry!

First off I, don't want to scare you, but you might want to check this out SADS Organization

Here is another site in Canada that has information too:
https://www.sads.ca/frameset2.html

Facts about Sudden Death & Cardiac Arrhythmia Disorders:

My 16 year old daughter has a borderline case of what they refer to as Long QT syndrome. She blacked out twice in one summer. She has to make sure she is properly hydrated all the time, but since she is borderline she can still ride her bike and be a normal teenager.

This is the often undiagnosed or unrecognized malady that you hear about when some seemingly healthy young athlete just keels over in the midddle of a basketball game or track meet. Best to have a doctor have a look see and do an EKG. That's how they tell what's up with a person's heart beat.

Then again it could just as easily be a symptom of some other easily diagnosed health problem. You also might be too old (20 doesn't seem that old to me) to fit into those categories. I would think if there was anything majorly wrong your pediatrician would have caught it when you were a kid.

Good luck.

I was just at the doctor a week ago and my blood pressure as the nurse said was very good. This was the first time this happend. I rode hard today for about 2 1/2 hours and felt great all day and it was a hot day. I have been riding for about 3 months and this was the first time it happend. I had got up a 7 that morning and had 2 waffles a coke and a bottle of water and rode at 9.

Perhaps you experienced what happens when your heart rate is high, your body is pushing all your blood to the peripheral blood vessels to attempt to cool your body down in the breeze you create as you ride, and when you stopped suddenly your heart was still pumping but your body was not cooling and you had a lack of blood to your head, causing you to "black out" as your body still tried to cool?

Or something like that.

I have had this explained to me as the primary reason for a "cool down" period rather than a "sudden stop" after very heavy exertion - especially when things get a bit warm. I have been told that your heart may even beat FASTER after stopping with no cool down period as your body attempts to cool down.

Fox, you may be right because I had arm warmers on and got really hot as i was riding up the hill and my head started sweating and getting itchy from the sweat, and when i stopped I started to sweat bad, this does not happen when I cool down, today it was 88 here in Augusta Ga and had no such expieriences like yesterday, cooled down after ride and felt great and still do now.

Oh my! 29F & snow here today!

ngate, is right

don't kill yourself over a hill

Jacob

Now, I knew a girl who blacked out on one of our local climbs. And I have seen a few crashes that I believe were caused by riders who were pushing so hard as to be very near to blackout . So your situation may not be any reason for alarm.

But, otherwise healthy young people, do die every year from undiagnosed heart problems and I believe most of these are now treatable. So going and seeing a cardiologist would probably be a good idea.

You may have done a valsalva maneuver (https://www.chclibrary.org/micromed/00069910.html) where the strain of going up hill and slightly improper breathing technique caused you to increase the intrabdominal, intrathoracic pressure and stimulated the vagus nerve, which signals the heart to slow down. That's why some people pass out when straining during a real difficult bowel movement. (I know, not a pretty discussion topic). It is a normal physiolgic mechanism but it also is a diagnostic tool for uncovering pathological heart conditions such as IHSS (idiopathic hypertrophic subaortic stenosis etc.) However, I would recommend at the very least an echocardiogram and EKG and a cardiology consultation.

In diving we call the basic method of equalizing airspaces (ears) the Valsalva maneuver. Its the old hold your nose and blow gently routine.

Marty

Same thing.

It is basically holding your breath while exerting yourself.

It has a range of different uses, but can be very dangerous as it causes extremely high localised blood pressure. Strength athletes utilises it as it helps brace the core and makes more power.

I doubt you would be using it on a hill climb though... But the same premise applies. A lot of athletes hold their breath inadvertantly while strained which can cause problems similar to this. It is very important to breathe properly when you age, as this type of thing can turn tragic very quickly in the ederly.

I've seen this happen to people before in my indoor cycling classes. In fact, I had a guy pass out tonight on me at the end of class.

We were doing a class of hill repeats, and at the end of class, I threw in a 1 minute sprint. Our cool down was not as long as normal, due to the fact that they cut my class to 45 minutes, as opposed to the usual hour. The guy told me he felt dizzy, then fell. Unluckily, I'd seen this before in my classes, and I'd done my usual first aid class, so I got him on the ground, elevated his feet, and within a minute, he was back to normal. The entire time he was on the ground, I was directing people to call the club first aid coordinator and got another person to help me keep the guy calm.

As I explained to him, I'll explain to you:

When someone is doing an aerobic activity that involves a lot of lower body muscle work (like cycling), the blood flow is redistributed and re-routed mostly to the working muscles. At the end of the training session, it's always important to do a cool down so that the blood can get shunted back to the upper body, including the brain. Failure to do this adequately enough may result in the blood becoming "pooled" or trapped in the legs. If you stop suddenly, the blood doesn't have enough time to redistribute itself to the upper body and brain, and this lack of blood may make you feel light headed.

I explained this to him as he lay on the floor, and I elevated his feet and told him that I was elevating his feet to help him get the blood back to to the upper extremities. By the time a minute had passed, the first aid coordinator was down in front of me, but the guy was ok- he got up and laughed and cracked a joke and walked out.

If you start feeling dizzy or lightheaded again, it may be wise to lay down and elevate your feet as quickly as possible. If someone has some tepid water and can help hold your head, you can drink a little water. Then just take some deep breaths, and within a couple of minutes, you should be back to normal. If you aren't, at that point, it may be a good idea to seek medical attention ASAP. There could be other underlying medical causes we don't know anything about.


Koffee

Good point koffee, although my only concern is vladmir's pruported slow heartrate preceding this episode. The phenomenom of intravascular pooling in the legs would lower the central, core intravascular volume and there would be reflex tacycardia rather than a slow heart rate. Just curious, was the spinner's heart rate thready and tachycardic or fast?

CB, I didn't know. Unfortunately, I was not able to check heart rate. They don't wear monitors at that club. I would venture to say it was thread and tachycardic if I had to guess, since we'd finished class and had the cooldown and the stretch by the time he'd passed out.

Koffee

Guys, Im not sure exactly how slow my heartrate was as i was not wearing a monitor, my heart just felt to be slow, another thing I should have said earlier was this was my second time doing this route, and the first time I got a little dizzy at the gas station but did not "black out". I have done harder hills sense then and have had no problem at all. i believe the problem was because of not an adequate cooldown.

lol i hate to call back an old post ... but what sort of recovery are you getting?

and i second the motion of everyone who said to see a doctor. 20 is not too young to have health problems.

During the time of my blackout I know i was overtraining from a post I did about a training program. Since then I have devised a program with Joe Friels Cycling Bible and wich is working great and I feel great every time out on the bike. Before i was going hard every day and leading up to the blackout it had been about two weeks of hard riding every day. I now know that rest is as important as riding thanks to the training bible and in my opinion I am now training with a proper schedule.