After a brief but welcome Indian Summer we had rain and thunder yesterday afternoon. It’s like returning to normality after a glorious period of dry trails and has meant that my last ride using the 2004 vintage Whyte JW4 may be it’s last outing of the year. I don’t like to put my classic mountain bikes through too much mud because it wears them out and spare parts for older bikes are becoming increasingly rare. 17 years may not be a massive time period in other fields. Cars from that time drive in a similar way to today’s cars but mountain bikes have gone through a massive transformation. Gone is the road bike geometry and 26″ wheels. Aluminium frames are still popular but carbon fibre is looking like the future and dominates top of the range bikes. I was back to normality riding my 2016 Boardman FS Pro which has been replaced twice by the manufacturer subsequently. Mud and a nearly contemporary bike. It’s the kind of normality I like.
I’ve given cadence, which is the rate at which the pedals are rotated, a lot of thought recently. I have established that by riding at a higher cadence but using lower force to turn the pedals I can save my leg muscles. Hill climbing becomes easier by using a lower gear and spinning the pedals rather than grinding them round. The only disadvantage is that my breathing increases with the pedal speed. What I hadn’t determined was whether I was faster or slower at a higher cadence. I love doing a quasi scientific test on my bike so thought that I should ride some laps at high and low pedal speed to check the effect on muscle fatigue, breathing rate and time per lap. Healey Nab is ideal, with it’s red graded circuit. The climbs are steep and it’s rarely level for more than a few pedal turns. I would just have to feel my way around each lap, listening to my breathing and feeling my muscles. I had no other metric by which to asses my riding. I decided to ride the first lap at a cadence of around 90 rpm. I’ve got used to how this feels in previous tests but have no way to accurately measure it. It’s easy to put a fast first lap in unintentionally and by riding with more power at a lower pedal speed I would have expected to be at my fastest so it seemed prudent to use the faster pedalling rate first.
Despite the rain yesterday and over night the trails are well drained and I rode lap one from a low point in 11 minutes and 15 seconds. I was panting for quite a lot of the circuit but hardly feeling it in my legs. I changed down a gear as soon as the gradient steepened and had a short rest before lap 2.
This time I deliberately kept the pedal speed down by using higher gears and could feel the extra stress in my legs. It’s surprising, then, that with a seemingly bigger effort my breathing was far more controlled. Perhaps it’s just because I’m fairly fit and well used to hill climbing but I didn’t have any lasting muscle fatigue after the lap and my breathing settled far more quickly than after lap 1. I was considerably faster at 10 minutes and 55 seconds. Does this prove anything? It seems to suggest that if I want a fast lap I’m going to need to push the pedals harder and worry less about spinning them quickly. Of course after many more laps I might have had the payback in terms of far fresher legs if I’d maintained a higher cadence. Over a long ride I could well eat into the speed advantage of using a higher turning force. I decided on an in between method for lap 3. I’d use more force on the climbs but still keep the pedal speed up on the easier parts. I recorded 11 minutes and 3 seconds but the extra 8 seconds could have been due to it being my third lap out of three. I was breathing fast again during the lap and at the end, taking a while to calm the rate.
I found it a very interesting ride and completed it with a fourth climb and off piste descent, since I was the only person on the hill. So there you have it. You can chose between putting the stress on your lungs at a high cadence like 90 rpm or put it on your muscles at a cadence of 60 to 75 rpm. What we need to do is decide on what best suits each ride. On a long ride with lots of climbing I’ll certainly try to keep the pedal speed up to save my leg muscles. If I want to climb quickly on a shorter ride I’ll risk the leg muscles far more. To get anywhere off road as quickly as possible I’ll just go for it and make sure I leave nothing in the tank.
Mountainbiker 