Lots of folks on here are talking about center of gravity and balance..staying in a lane etc.. It doesn't bother me at all if many here don't agree with the potential benefits of rollers, but I think the conversation should at least be on the right topic. I'll explain. Riding rollers has only a little bit to do with 'staying in the lane.' Sure, if you go out of the lane you fall off the rollers, but that's only a tiny piece of the puzzle. A few folks here have mentioned 'smoothness,' which is partly true, but not in a directional sense. What regular training on the rollers will do is allow you to go really hard without your pedal stroke effecting your direction of travel. This has little to do with 'steering' inputs, and far more to do with keeping your pedals working in the ways they should, and not working in the ways they shouldn't. If you can ride really hard without a flailing pulsation in your steering or acceleration, you'll be able to ride with a relaxed upper body. We've all seen guys who seem to motor along as if they're barely working. Guess what, they could probably let go of the bars, put their arms behind them and keep that same cadence/smoothness without getting sketchy, simply because they're turning the pedals along their intended path, not controlling the entire bike as a side-effect. This is especially apparent when comparing folks from your local group rides with the big dogs in the tour. Many people don't realize how fast a cadence some of the pro's ride during time trials. Even Cancellara turns a pretty fast gear, and yet he looks like a smooth running machine. With the kind of watt's that guy puts down, you'd expect his bike to be straining left and right, and yet, it doesn't.

Riding and training on rollers (specifically resistance rollers, because yes, we want to get a muscular work out also) helps to train you to ride efficiently. After my winter season spending lots of time on rollers, doing intervals, one leg drills, pyramid sets etc.... I found that in the same group rides of the previous season, I was perhaps no 'stronger,' but because I was using my hamstrings, calves and glutes more when the pace was steady, I was able kick harder and dig deeper when I needed to mash away with quads alone. I've heard the studies that show that 'during all the critical times of races, pro's basically mash, with no force being exerted on the upstroke.' I actually believe that, and think it can teach us something...but what it doesn't disprove is the value of resting your 'mashing' muscles outside of the critical points and allowing them to be as fresh as possible specifically for WHEN the real work begins.

Just food for thought. I'll a await the inevitable rebuttal, proving that rollers are a useless thing of the past, with nothing more to offer in today's day and age.

-Jeremy