Is it normal to feel sick after a ride?

[aJohnson]

Thinking about getting a cheap hrm (Don't have much money)...
http://cgi.ebay.co.uk/Heart-Pulse-R...g_MJ?hash=item4a99dcfe6e&_trksid=p3286.c0.m14

 

[matason]

Lactic acid perhaps?

I could be way off the mark here but doesn't lactic acid make you feel sick?

 

[Medic6666]

i tend to be sick during a ride, get it out the way early