I’m beginning to notice a trend. The more often I ride my fixed-gear bike, the more comfortable it seems to get. Last week I took my first ride on it in about 3 weeks, and my shoulders and wrists were bothering me after the first half hour. Now, a week and about 5 rides later, I’m not having the problem any more.
Here’s my theory. On a fixed gear bike, it’s impossible to coast. On a bike with a freewheel, you can “take a break” and coast when going downhill. When coasting, you can support most of your weight with your legs, even if you’re tired. On a fixed gear, as you get tired, most of that weight ends up going to your arms/shoulders and rear end, particularly when spinning downhill. As you start to get “used” to riding fixed, your legs start to pick up more of the slack, so the bike gets more comfortable. My observation is that I start to lose this conditioning with any significant time off the bike (say, more than a week). So, more so than with other bikes, it’s important to keep riding fixed regularly to maintain conditioning.