When I started to bicycle, I did not use a bicycle computer. I felt I didn’t need to know my speed or heart rate, nor any other “data”, for that matter. Then, as I started to get more into bicycling, I felt a need to learn more and started to read about bicycling. I read about mountain biking versus road biking, about how to maintain and repair bikes, about training, and so forth.
Soon I found that I probably had been wrong about not wanting to use a bicycle computer. Using one, and collecting some data, actually seemed to make a lot of sense, for a number of reasons. What I especially focussed on was that keeping track of speed can be good for motivational reasons and that using a heart rate monitor can help in training.
So I went out and bought a bike computer. More or less by accident I happened to buy one that also measures cadence. And, as it turns out, that was very fortunate!
These days, after having used my bicycling computer for about one and a half year, it is actually cadence that I am most concerned about and pay the most attention to. I try to keep my speed up and while heart rate may be important for optimal training for Tour de France, it doesn’t seem all that important in my Tours for Exercize
Why is cadence important?
I didn’t think about cadence as important at all when I started to bicycle. Frankly, I don’t think I knew what it was even. Cadence is the speed at which one pedals. In bicycling, as in many other areas, this is measured in revolutions per minute, or rpm. If one foot pedals a full circle once every second, that means you are cycling at 60 rpm.
There are at least three good reasons for paying attention to cadence. First, when cadence is higher the strain on muscles and joints (knees) is lower. Second, regulating cadence is a means of balancing the work between muscles and heart/lungs. And, third, partly as a consequence of the second, biking at the right cadence makes it easier to bike for longer and harder rides.
For me all of these reasons are important. However, given that my knees are bad from many, many years of playing soccer, reducing the strain on my joints is the most important to me.
When I started bicycling, I would use the muscles in my thighs a lot. I kind of liked the feeling of working them, feeling them push and propel me forward. So when I installed my biking computer, my cadence would often be around 45 to 55. And my thighs would often be burning and I would run out of juice quickly. And often my poor knees would hurt for a while after a ride, sometimes keeping me awake at night.
So I learned about the importance of biking at higher – quite a lot higher, as it turned out – cadences in order to bike more efficiently and reduce the strain on my knees. These days conventional wisdom says that cadence ought to be approximately 85 to 110 rpm, and, indeed, advanced cyclists tend to bike with cadences above 85. Lance Armstrong was famous for cadences above 110 uphill!
Cadence and endurance
Some research also holds that the aerobic performance is best at these higher cadences. When pedaling fast, the body delivers more blood to and from the heart. This means that blood will have higher oxygen levels, improving aerobic performance.
The reason higher cadence is more effective has to do with the way our muscles work. There are two different chemical reactions our muscles can use to produce power: aerobic and anaerobic. Aerobic reactions use glucose and oxygen from the bloodstream, and can be continued for as long as there is glucose and oxygen in the bloodstream. Anaerobic reactions use glycogen, which is stored in limited supply in the muscles, do not use oxygen from the bloodstream (hence the name), and produce lactic acid as a byproduct. The supply of glycogen in the average fit person’s muscles is enough to last for about 10 minutes; when it is gone, it is gone for the day. Once your glycogen stores are gone, you are bonked; you will be able to continue riding flats at 10-12 MPH, but you will have no energy to handle headwinds or hills, and you will not be having any fun. Therefore, a cyclist interested in riding for more than 10 minutes should jealously guard his stored glycogen by keeping his cadence high.
If you are accustomed to a lower cadence, pedaling at 80 RPM will probably feel wrong. You will probably feel like you’re not doing as much work–because you’re not! Your speed may drop somewhat but your range will increase dramatically, as will your enjoyment of cycling. You will finish your rides feeling tired but relaxed, free of pain, and ready to ride again tomorrow. — from inl.org Bicycling blog
The ongoing fight for higher cadence
So I started to try to push myself to bike at higher cadences. However, achieving this isn’t easy, at least not for me. I often find myself slacking and letting the cadence drop to 50-60 while I ponder or daydream. However, when I notice those low numbers on the computer screen, I shift to an easier gear and drive the numbers up to 85 or more.
Keeping track of cadence to become a better cyclist
For the moment, and actually for the last year, I have been much more concerned with using cadence to teach myself to bike correctly than I am with for instance speed or average speed. I want to teach myself to do hills with a cadence of at least 90, and flats at 85 or above.
So I try to incorporate spinning sprints, where I drive the cadence up to 120-140 for as long as I am able, more or less every time I go out on a ride.
I have read somewhere that cyclists sometimes are identified as “mashers” or “spinners.” A masher is someone who likes to race by pedaling hard on high gears with low or moderate cadences. A spinner, on the other hand, races on low gears with high cadences. I think I am a masher slowly turning myself into a spinner.
I think I am slowly winning the battle against my «natural inclination» to bike at low cadence. But for me it is a battle that takes will and determination, and it also is a battle I know I would not have a fighting chance to win without a biking computer. So that’s the reason I bike with one!