Will a Fixie Foul Up My Knees?

Question: I’ve been riding a fixed-gear bike occasionally for a few years, mainly during the winter months. I’ve enjoyed the purity of the riding experience, and the workout is definitely intensified and compressed. However, besides the fear of crashing, which seems to keep my senses sharpened, I am concerned that riding a fixed gear increases my risk of knee injury, especially as I get older (40+). I don’t show any symptoms, but a friend says that trainers and orthopedics are now seeing more knee injuries due to fixed-gear riding. I believe I am geared appropriately (about 70 gear inches) for my level of fitness and the rolling terrain here in Maryland. I keep my knees well covered in the cold. Should I be concerned? – Jesse F.

Coach Fred Matheny Replies: There doesn’t seem to be any evidence that fixed-gear riding by itself causes knee injuries. After all, trackies by the thousands have done fine on fixed gears since the bicycle was invented.

(Note: “Fixed gear” means one speed and no freewheel. The bike has a single chainring and rear cog, and when it rolls the crank turns – no coasting.)

That said, here are some factors that could lead to a greater risk of injury if you’re riding a fixed-gear bike.

• Pre-existing knee problems. Some knee conditions are exacerbated by the “locked-in” nature of a fixed gear. The risk varies depending on the individual’s knee history.
• No brakes. A fixie on the road should have brakes for safety reasons. If it doesn’t and you must slow or stop by resisting the crank with your legs, it puts a large strain on the knees.
• Too large a gear. Or terrain that’s too steep. If a fixed gear makes you muscle over hills with a cadence below 70 rpm, it’s hard on knees. This isn’t a good situation on any bike, including one that’s derailleur-equipped but geared too high for the terrain.
• Poor riding position. I assume you have your fixie set up like your road bike. But some riders who put a fixed-gear bike together neglect to duplicate saddle height, saddle setback and reach to the handlebar. For riders with sensitive knees, even a different saddle might cause problems if it repositions the sit bones.
• Forgetfulness. Most riders that switch between a road bike and a fixed-gear bike forget occasionally and try to coast. That can cause a rather violent thrust on the legs and maybe a quick trip over the handlebar. Even short lapses that merely cause a jerk in the pedaling motion can bother the knees.

I suspect that due to the increasing popularity of fixed-gear riding, we’ll soon have more definitive answers in the form of studies and clinical experience. Meanwhile, if you aren’t having knee issues while riding your fixie, it’s unlikely you’re doing any damage. Just don’t forget to pedal!