Non-linear Cycling Dynamics (or Why I Can’t Go Faster)

When the mind wanders...

So here’s the deal. Simple Newtonian physics problem: if you pick up a box, and carry it across a room, you’ve done a set amount of work. If you double the weight of the box, you’ve done twice as much work, right? So what happens if you double the size of the room, but cut the box in half?

Well, if you cut out the bottom-half of the box, you’re doing almost no work, because everything will have fallen out. But assuming you just removed half the weight of the box, then you could carry it twice the distance without doing any more work.

Simple, right?

Unfortunately, this has very little to do with riding. It didn’t really dawn on me until recently. I’ve been switching between short rides of 16-20 miles, and medium rides of 40-50 miles. I figured for those days when I could get out and train for a while, I’d put in some good miles at a decent pace, usually around 18 mph. And for those days without much time to spare, I’d hammer out a quick 16-20 as fast as I could.

What I didn’t notice was that – despite trying my best on those shorter rides – my average speed wasn’t increasing that much. Instead of doing 18 mph, I might (on a good day) hit a 18.5 mph average. I didn’t get it. I was going only half the distance… shouldn’t I have averaged a lot better speed? I mean, I had a lot more in the tank. What gives?

Why wasn’t I able to pump up the speed? Turns out I wasn’t thinking right. Stop laughing, I know that’s a common occurrence for me.

Your speed is determined by the amount of power your body can transfer to the bike, the efficiency of that bike in converting that applied power into forward motion, and of course external factors: wind resistance/assistance, hills, mountains, walls, heart-rate boosting dogs, etc.

When you’re just starting out on a ride, your energy reserves are topped off and ready to go. And without any muscle fatigue, you can hit your maximum power output. Over a shorter distance you’ll have less fatigue and so your power output won’t decrease much. When you do endurance training, you’re teaching your body to fight off fatigue and use what energy you have more efficiently so you can maintain high or even max power output longer.

It turns out no matter how short my short rides were in comparison to my medium rides, my ability to output more power at a given time wasn’t going to increase. That requires a whole different type of training I hadn’t been doing. I’d come off the shorter rides less fatigued is all. And instead of being upset that I wasn’t going much faster on my short rides, I should’ve looked at it from the opposite end. I should’ve been happy that my longer rides were maintaining an average speed that was close to my short ride averages, which meant that my endurance training had been paying off and I’m not losing as must power output over longer distances.

So, moral of the story: if you want to be able to ride faster, train to ride faster. If you want to ride further, train to ride further. If you want to ride faster and further? Install a motor. No, not really. But just make sure you train on what you want to improve and don’t judge yourself on things you haven’t specifically trained.

Cycling teaches us to keep¬†things turning over and over: the wheels, the crank, the gears, the pedals, and it seems the ideas we mull.¬†But sometimes, you’ll save a lot of headache if you just turn it around.