Faintness from accelerating hard

I almost never accelerate hard from standing, but last night I did, and after a couple of seconds I felt a bit faint. I backed it off and the faintness went very quickly. I can see why this happens when your head is forward of the rest of your body, but I'd never heard of it happening on a motorcycle before, and Google reveals nothing. My blood pressure is normal, but I do get a bit dizzy sometimes when standing quickly after squatting down to do weeding etc. My question is, is what happened within the bounds of normal, or should I think of getting medically checked for it?

This sounds concerning, certainly not something that I have experienced while riding a bike.

I'd say definitely worth getting yourself checked out, you certainly wouldn't want it to get to the stage where you lost consciousness while riding.

Best wishes for a speedy resolution.

That sounds like G induced gray out. I've experienced it in a jet pulling 5.5g with no G-suit. But if it happens at the 1.5-2g acceleration on a bike would indicate you have a blood pressure or flow issue. Go see a Doctor, especially if you get same standing up quickly. 
 

Better safe than sorry ! 🤔

Right, thanks guys. The head-rush when standing is supposedly common with people with Chronic Fatigue Syndrome (I have a mild case), where the body doesn't react fast enough to boost blood flow to the head, so I assume I would be more prone to this with G-forces than most people. I will check in with the doctor to make sure it's nothing else, and I'll avoid such hard standing starts again.

There are a myriad of factors that can affect 'g' tolerance which is why warm up's are practised before pulling serious 'g' in order to spot issues like this an cease any further exposure before safety is compromised.

Even at such low exposure levels, it is possible to feel the effects of 'g' if you are unwell (say, an ear infection), are fatigued, alcohol, drugs etc etc, even time since your last meal but it could be a more chronic sign so as has been said, definitely go and see your doc.

This happens to me at times if I'm dehydrated. In hot weather I make sure to stop occasionally and drink a Gatorade or similar

The general rule of thumb for climbers / backpackers is that "if you don't need to pee before starting out, you're dehydrated".  I wrestle with that on rides,  particlarly group ones, as rest stops do not always present theselves, and I don't want to have a bursting bladder 20 mins. on.  OTOH, dehydration reduces mental and overall abilities so isn't great when riding.  I always carry extra and drink when I can.

45 minutes ago, Cogswell

The general rule of thumb for climbers / backpackers is that "if you don't need to pee before starting out, you're dehydrated".  I wrestle with that on rides,  particlarly group ones, as rest stops do not always present theselves, and I don't want to have a bursting bladder 20 mins. on.  OTOH, dehydration reduces mental and overall abilities so isn't great when riding.  I always carry extra and drink when I can.

TBH, it all depends on the climate and your riding gear. 

I would only be concerned about dehydration if I was in a very warm climate (30+ deg C), didn't drink much water and went riding for a long time in unsuitable gear.

I see people running round here carrying water bottles....all they're doing is making it harder to run as they're carrying more weight (which may be a good thing for some) and it's completely unnecessary if you are hydrated before you go. I sweat like a sweaty thing but still don't need a drink whilst I'm running.

YMMV

HareBrain, 6/24/2021 at 11:59 AM

Right, thanks guys. The head-rush when standing is supposedly common with people with Chronic Fatigue Syndrome (I have a mild case), where the body doesn't react fast enough to boost blood flow to the head, so I assume I would be more prone to this with G-forces than most people. I will check in with the doctor to make sure it's nothing else, and I'll avoid such hard standing starts again.

You had better watch he doesn’t suspend your license whilst checking this out.