I've been lurking around reading about HIIT in this forum. I'm just getting back into the groove for fitness and I want to lose around 10lbs (what I put on since I stopped regular exercise). Now, from past experience, I know intense cardio activity (Just high level 10-15 minute non interval... probably approaching AT but I'm not sure 'cause I don't have a HR monitor) tends to, for lack of a better term, make me stupid. It's as if all my blood is going to my body instead of my brain. It's caused me to make some seriously life-threatening errors in judgement when cycling in traffic, because I just can't think straight. I generally have decreased motor skills too. I get off the bike shaking and bump into things, stumble around and so on. This feeling usually passes about 20-45 minutes after the cardio is over. I've "bonked" before due to lack of carbs and this isn't the same. I have lots of (well, some) energy left, I don't have a headache or anything.

Does anyone else get this? Is there anything I can do to lessen the effects?

I'm a cyclist by choice, but I think if I'm going to do intervals, I'll do it on a treadmill or exercise bike instead so I don't end up as street pizza.

I know what you mean. That has happened to me in competitive sports and after sprinting.

I don't know the exact explanation for it yet, but I've been there.

I wonder if the brain glucose levels decrease radically, probably not because there has to be some factor of safety there? Also there is a battle for oxygen between the muscles and the brain so that might be part of it.

I do all of mine in the gym, so the worst I'll do is make a dumb comment or trip over myself while staring at some hot chick!

I used to runt cross country. Got up at the crack of dawn to run 5 miles or more every morning. I know exactly what you are saying though... I did some of my best thinking while running though

But after any intense workout you will loose motor skills for a short while. I found especially bad after a 3k race, prolly b/c the adrenaline stacked on top of the heart beat.

If you are dying to experience this effect, try wall climbing and balancing a tray of drinks afterwards.