The gears on your bicycle do the same thing as the gears in the transmission of your car. It's not just about of going faster, but doing it more efficiently. Getting the most out of what the engine has to offer, using the least amount of fuel. On a bicycle this is even more important because the engine hasn't nearly as much power to work with, so you want to squeeze as much as possible out of what it has to offer.

So how do you get the most "miles per pasta"? By selecting the correct gear for the job. Like a car's engine, a bike's engine works best at a certain RPM. The idea is to apply power around the entire pedal stroke, yet do it smoothly and as evenly as possible. This is called spinning.

What is the best RPM? That differs for each individual. Not only that, but it will vary slightly as cycling conditions change. It's easy to spin a high RPM on the flats, but not easy on the hills. My spin varies from about 80-85 RPM on the flats, but when the going gets tough, I may drop as low as 75 RPM. Most of the time though I'll be spinning close to 80.

The point is that I remain within a narrow range of pedaling speeds. I remain within this range by shifting gears. Not just any gear, but the highest one in which I can comfortably maintain my cadence (pedal RPM). Using this method I have gone as much as 300 miles in one day.

Now, just because I have a cadence of 80 RPM doesn't mean that your best cadence will be 80 also. As I said, it varies from individual to individual. But usually the ideal cadence will fall somewhere between 70 to 100 RPM. Yes, there are actually people that spin that fast! Usually competitive cyclists prefer a faster cadence. While recreational cyclists and tourists tend to prefer something a little more conservative.

As conditions change during your ride, like wind and hills, find the gear in which you feel you could maintain your proper cadence indefinatly. But not too easy. You'll end up "burning yourself out". You wouldn't drive your car down the freeway in 2nd gear, would you? If it feels too easy, like you could push a little harder yet still pedal comfortably, shift to a higher gear. if you feel like your straining unnecessarilly, shift down. The idea is maintain an aerobic level of exersize.

Aerobic means "with oxygen". In other words your muscles can do the amount of work required of them by using oxygen and glucose (blood sugar) supplied by your lungs, heart, and digestive system. As long as you can continue to supply these muscles with food and air, you can ride almost indefinatelly. If you want to be able to ride farther, simply go a little farther each time you ride.

But suppose you want to increase your strength. so you can ride faster, or climb better. Then you have to push yourself a little harder. In order to increase strength, you have to go a little bit beyond an aerobic workout. You need an anerobic workout. Anerobic means "without oxygen". The amount of work your muscles are doing requires more than your heart and lungs can supply, so the have to call on a different source. This source is called glycogen, and it's stored in the muscle itself.

How do you know when you are exercizing aerobically or anerobically? Well, you can buy an expensive heart moniter and do the math to find out, or you can simply judge by your breathing. If you can control your breathing, you're working aerobically. I like to "pace" my breating to my pedaling. For example:

IN (left, right, left,) OUT (right, left, right,) IN (left, right, left,) etc.

You can use a three count like this one, or you can use some other rhythym. The point is, as long as you can control your breathing, you're aerobic. When you can't control your breathing like this, when you find yourself panting, that means your cardiovascular system can't keep up. Your anerobic. The trick is to find the gear that lets you work right "on the edge". (This is where knowing your bikes "shifting pattern" comes in handy. If you know where each gear is, you can go directly to the one you want, instead of fumbling around looking for the right one.)

The problem with using glycogen as an energy source is that, one, it's inefficient, it leaves large amounts of a waste product called lactic acid, this is what causes that "burning feeling" when you work hard, and can cause cramps if too much builds up. So be sure to do a "warm down" before you end a hard ride. Pedal easilly for about five minutes before stopping, that will pump out most of the "poisons"

Also, probably more importantly, your supply of muscle glcogen is limited, and once it's gone, that's it. No more hard work for you. This is called the "bonk". You can still pedal, but only easily. try to pedal hard and there's simply nothing there. and it will take your body from 24 to 48 hours to process and replace your full supply. So save your strength training for the short rides.