^^ me either

personally I think alot of people have bad bike fit(too low/high saddle and bad pedal/foot position)...........then they get on and ride awhile, and because a freewheel bike is easier to ride and they dont get pains they immediately blame the fixed gear. Many also jump on it and get way over their head fitness wise too.

Im not buying it. People here want to put limits on gear ratio or insist on brakes, ok thats fine, so this implies rather explicitly that A) fixed gear is more than the human body can handle and B) the "unnatural" pedaling stresses are too much. This also means that guys like me must be freaks of nature, and Im not buying that either. Ive spent way too many miles riding and been thru the pains of what wrong bike fit does. Ive spent too much time riding fixed pain free to think its messing up my knees too. I also know it can take months of riding and small tweaks here and there to get a bike dialed in. The other people I know that ride fixed for work daily must be freaks too, and they arent. Heck we have one guy here that rides with a pre-existing knee injury and he's fine.

The more you ride in a short period of time the quicker problems will show as pain, same for just riding harder. Riding fixed just amplifies things a bit. You cant hide on a fixed gear. If youve got fit issues, bad technique, lack of fitness which includes tendon and ligament strengthening which comes with riding regularly, then yep, you get on a fixed and ride a bunch, and it can hurt. But you can get on a freewheel bike and do the same damage. This is one of the reasons prettymuch all the roadie training books require base training, besides cardio conditioning it also provides strength training for the legs so you dont tear something when the real hard efforts come later.

then you get pedaling theory from roadgator..........ok, how many people here apply more force when back pedaling with front foot pulling up than the rear foot pushing down? I dont, in fact I mostly push down. The front foot barely gets pulled on at all, just like pedaling forward, the foot pushing down does most of the work. As for skidding, anyone with lots of experience will likely admit that its a finesse maneuver, not brute strength, and standing with legs extended or almost extended they can handle lots of force in either direction.

Lastly, something as simple as foot position over the pedal freewheel or fixed can screw up your knees and put you off the bike. Been there done that. Culprit was as simple as toe cages that werent deep enough. Even only wearing size 10's it seems the cages that put my foot over the pedal where needed arent too common. I see people that ride for a living with all sorts of sins in the fit dept, it happens. Some take the time and effort to find out why and set the bike up so it doesnt hurt, others just blame the bike.