Cadence is the rate at which you spin the pedals on your mountain bike, or other pedal powered contraption, for that matter. My own cadence has come to my notice not through cycling but as a result of using my pedal powered boat. A cycling cadence for a road rider will usually be in the 80 to 90 rpm range but I found when pedalling my boat my cadence was as low as 30 rpm! This is very low and has an interesting effect. It doesn’t make you breath quickly even when you’re applying moderate effort but it does tire your muscles after a period of sailing. What is clearly happening is that my muscles are using my instant energy stores in the form of glycogen, not processing oxygen to power the muscles. It’s not a field I know a vast amount about but I do know that there are slow twitch and fast twitch muscles. Some riders deliberately train at a lower cadence (though nowhere near as low as 30) to strengthen their muscles and presumably also spin the pedals at a higher rate on other training rides to complete the picture and train both muscle types. I wondered today what my own cadence would look like on a mountain bike ride and resolved to try some segments at deliberately slower and faster rates of rotation to see if this had any effect.
Along a flat dirt trail I measured 74 rpm, which is slower than a road rider, according to my small amount of research. I then noticed that as I climbed a fairly steep slope my rate dropped. What was happening was that when the gradient suddenly steepened there was no time to change down the gear for what might only have been a few meters before the gradient slackened again. Instead I was upping the muscular effort and grinding it out, reducing my cadence considerably. Over a minute of varying gradient I recorded 68 rpm, which surprised me by being so little different than on the flat. As the gradients became even steeper, at least for short sections, my rate dropped again to 64. I decided that I’d ride some sections twice, once at a grind then at a spin or vice versa.
On a gravelly climb with a fairly constant gradient I first rode in my usual style in 35 seconds. I could feel my muscles and completed a lap of the hill to then up my cadence by choosing a lower gear. My muscles were less stressed but it took me and extra 3 seconds. My testing was not detailed enough to know whether I was breathing any faster. I tried the same thing on the top loop which took me 2 minutes 11 seconds first time. This is a circuit which drops then climbs back up. A lap later I spun more quickly and seemed to definitely be breathing faster but stressing the leg muscles less. A good test since it only took me a single extra second.
It could be that through a diet of off road riding I’ve come to position where my cadence will tend to be low compared to road riders. I can’t help but think that on a long ride I will tire my muscles less by spinning up hills where possible, saving the big muscular efforts for places where there is no other choice. This could be useful information for my planned long ride with around 5,000 feet of ascent.
I’m sure that if I looked I could find a device to monitor my rate of pedalling. I could also monitor my wattage, heart rate and blood oxygen level. I know that professionals like Tom Piddock, our Olympic MTB XC gold medallist, use this kind of technology to tell them what effort to apply throughout the ride. I may appear to be a Luddite but I think that this is basically cheating, though not perhaps if everyone does it. I think that any electrical input destroys one of the great joys of cycling which is that it’s just man and machine. A bike which adjusts it’s suspension electrically and changes gear in the same manner is just plain wrong. The energy input may be miniscule but the principal is massive. What do other riders think about the increase in computerised technology in cycling?