I was just after some ideas on how to stop my legs giving up after 2 laps on a rough track? I ride on a really whooped out sand track and after two or so laps I have hardly any strength left to lift my leg to put my rear brake on. I dont think its leg pump (if that is even a thing) or a fitness thing. It is just my legs cant keep me standing up which is what I need to do to ride this track. Is this a riding technique issue or is it my body issue? Its not like I am overweight but I am not a gym junkie or a fitness freak either. But some tips on how to improve would be sweet cheers!