FInd Your Optimal Cadence
Are you a grinder who’s constantly being told by coaches and training partners to go to an easier gear and spin faster? Maybe your cadence is too high and pushing a lower gear makes your legs feel like cement. Is there really such a thing as the perfect cadence? Triathletes and cyclists have long considered 90 rpm as the ideal. But, what do we really know about cadence and maximizing efficiency? As it turns out, not much.
Oliver Blake, a PhD candidate at Simon Fraser University, is studying the biomechanics and muscle recruitment patterns in cyclists. He explains that choosing the appropriate cadence is highly individualized and also dependent on the level of intensity required. He insists, “If absolute maximum power output is required then the cadence is going to be around 120 rpm, whereas interestingly, the one hour distance time-trial record is always set around 100–105 rpm and road distance cyclists will tend to use 90–100 rpm.” But all of us know powerful cyclists who never get out of their big ring even when climbing and yet always ride fast.
Wattage, or power output, is generated in two ways. The first is through torque or how much force is applied to the crank arms. The second is through cadence or rpm ( how fast the crank arms are spinning). Establishing the most efficient balance between the two depends on many factors including individual physiological makeup.
Physiologically speaking, there are two components to consider. First, when cadence decreases at a given workload, the torque or muscle force required must go up in order to maintain the same wattage. This takes a greater toll on the working muscle groups.
Greater muscle force at lower rpm often taps into fast-twitch muscle fibres, which in turn burn muscle glycogen more quickly than slow-twitch fibres. This has huge implications for endurance events like triathlon. Muscular fatigue after the bike can leave an athlete with little left in the tank for the run. Combine that with a larger decrease in muscle glycogen and it’s not a great way to set oneself up for the long haul. But, if spinning at a higher cadence fatigues riders with more power and less of an endurance base, the slightly lower cadence may be the best bet.
The second component to consider is the stress put on the heart and lungs (the aerobic system). As cadence increases while maintaining a constant wattage, more power is generated through rpm so less torque is required. This is less stressful on the muscles but will tax the heart and lungs. The more aerobically fit you are, the more favourable this option may be. There is of course a limit to how high rpm numbers can get before the benefits wane due to the speed of movement and muscle co-ordination required.
In a controlled race like a time trial or iron distance bike segment, if you are aerobically very fit and have trained to achieve higher rpm numbers then it may be beneficial to hold a higher rpm in order to save your legs muscularly for the run. However, there isn’t a magic number for every individual or situation. Ideal cadence will differ depending on effort, fitness level and the desired outcome.
A beginner will have a much harder time holding a high average cadence than a professional athlete. It can take years to develop the muscular coordination to sustain a higher cadence over an extended time period. Acquiring this skill is a good strategy in triathlon because it should create less muscular fatigue and help athletes utilize more slow-twitch muscle fibres.
What we know for sure is that cyclists who are more versatile are more likely to perform better in different scenarios and on different race courses. It ensues therefore, that we should learn to be comfortable at both higher and lower cadences. For this, cyclists can do specific rpm drills with a cadence sensor to switch up their cadences. One such drill is the Cadence Pyramid. This is usually done inside on a trainer or rollers with very little resistance. The rider starts at a lower cadence of 80 rpm and builds up to a higher rpm and then goes back down. Each step is held for one minute.
Over a few weeks aim to build up to 130 rpm at the top of the pyramid. Practicing different cadences will also help your neuromuscular response time and make you a more efficient cyclist.