From the Coaches: Why does cadence matter?

Cadence in cycling refers to the speed at which you are pedaling measured in revolutions per minute, or rpm. The power you produce is a direct product of pedal speed, with Power = Angular Velocity (pedal speed) x Torque (force applied at the pedal).
Based on this formula, it’s easy to see that as your pedaling speed increases, the force per pedal revolution drops to maintain the same power.

Less force per pedal revolution means less strain on your muscles. Less strain means less muscular fatigue, which ultimately results in an increased time to failure. You can ride at a given power for longer before your legs give out. Imagine trying to hold 100% of your MAP at 30 rpm. Most people wouldn’t make it to the 2.5-minute mark, let alone a full 5 minutes.

At the same time, you would also struggle to hit the 2.5-minute mark at 100% of MAP riding at 140rpm. Riding at high cadences results in a higher cardiovascular strain, which is entirely due to decreased efficiency. Most riders will have an efficiency of around 23%, meaning 23% of the energy the body uses turns into the power you can deliver to the bike.

At higher than regular cadences, efficiency can easily drop by 10%. In fact, during various cadence testing we have completed in our Boulder Lab, we have recorded sustained (4+ minutes) efficiency as low as 5.4%. So what does your body do with the rest of that energy if only 23% turns into bike power? Most of that energy converts to heat. That means riding at 250W results in around 800W of heat production, the same heating power as most bread toasters!

Extra heat production is not what happens to that 10% change when riding at higher cadences. This decreased efficiency is due to a neuromuscular phenomenon known as “co-contraction.” Before diving in too deep, it’s important to remember that muscles exert force by shortening. Co-contraction is when two sets of muscles around a joint (flexors and extensors) are active (trying to shorten) simultaneously. An example of this is flexing your biceps (elbow flexor) and triceps (elbow extensor) simultaneously. Your lower arm would not move despite the fact both muscle groups are using energy to contract.

Your muscles react to nerve signals to both contract and to relax. When riding at super high cadences, your body runs into the issue of not contracting and relaxing your leg muscles fast enough. You end up contracting your muscles at the wrong phases of the pedal stroke. This results in more “negative” force during each reset phase of the pedal stroke. In this sense, your legs are producing more power when at these higher cadences. It’s just that less of that power actually makes it to your wheel to help propel you forward. We refer to this co-contraction limiter in terms of neuromuscular coordination (NMC).

All of our movements, large and small, utilize co-contractions, meaning all movements have some level of required NMC. Think about are typing on a keyboard. The NMC of the muscles in your fingers and hands allows you to hit the right key at the right time with enough force to trigger the key but not so much you end up with bruise fingertips. Most people remember first learning how to type or write. At first, you are slow and a bit clumsy. You make mistakes. Over time you can type/write faster and faster with better accuracy. Your ability to type/write faster is mainly down to the improved NMC of your hands. Your finger muscles might have gotten stronger, but the ability to hit a key harder doesn’t result in faster typing.

You can view cadence on the bike in the same way. When most people first start riding, their cadence is naturally low, often below 60rpm. As NMC improves, the cadence at which co-contraction starts to occur increases. As NMC improves, people will ride at higher and higher cadences until around the 80-90 rpm mark. This improved NMC is strictly down to time “practicing” pedaling. While some of you might have actively trained to type faster, most people get faster at typing over time.

The main differences between typing and pedaling are the size of muscle groups involved and the “need” for co-contraction to control the movement. Larger muscle groups (legs vs. fingers) use significantly more energy, which requires oxygen. Our leg muscles can produce more power and therefore need more oxygen than our cardiovascular system can handle. You would have to type pretty fast to start breathing as hard as you do riding at your FTP.

Now consider that your legs will make perfect circles when pedaling because you are physically attached to a circular crank. When typing, you don’t just happen to hit the right key every time. You can actively try and type faster, but once you cross that NMC threshold, you might be hitting keys more quickly, but they won’t be the correct ones.

Why does this matter? It matters because improving your NMC on the bike means you can ride harder for longer. Fixed cranks by their design allow you to have very poor NMC and still make perfect circles. You wouldn’t even be able to complete most other sporting movements or day-to-day tasks with such poor NMC.

This is why Cadence Builds, Cadence Drills, and Cadence holds occur so frequently in all of our training plans. The only way to improve NMC is to push past your current limit of NMC. Since you are ‘locked in’ to your pedals and will always make perfect circles, pushing past your current pedaling NMC means riding at uncomfortably high cadences. These are also the best sessions to maintain a high level of NMC even once you feel you have “mastered” cadence builds and think you never need to do them again.

The increased efficiency from improved NMC impacts all intensity levels, not just top-end power. No one has ever ridden faster by being less efficient. Improving and maintaining your NMC will put you in a better position to achieve your cycling goals regardless of what those goals are.

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Grade A content as usual!

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Thank you for the fine read, @Coach.Mac.C. I really enjoy the cadence training sessions. When I began with the Sufferfest I didn’t realize what impact those sessions would make. In the past I was struggling at 100 rpm and didn’t like high cadence training sessions. Now it’s the opposite, I love high cadence workouts. If I do Revolver It’s a struggle to hit the power targets for the last 5 micro intervals. What I do is upping cadence by 5 and later 10 rpm. It saves my legs and helps me completing Revolver.

For cadence builds and holds I’m not entirely sure what the best strategy is. Because heart rate is the limiting factor the first 3 builds and 5 holds I conserve myself with 173ish for builds and 133ish for holds. Only the last build and hold I go all-out with 183ish for build and 137ish for hold. An other approach is to go all-out for every single build and hold. Or is there something else I can do?

Really love the Sufferfest by the way!!!

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@Coach.Mac.Cthanks for the explanations, indeed throughout the training sessions with Sufferfest, I have seen the evolution in the past I struggled with anything above 70 rpm, nowadays depending the loads I’m putting in the sessions, my average cadence is between 80 and 90rpm and my highest rpm is at 127!! and during cadence builds already at 153. But I still don’t like the cadence drills workouts! But mostly because the drills lack a story or music! So for me it really “stress” when a drill session comes up on my training plan! But, hey i wouldn’t have improved if they weren’t there. so thanks!

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Best explanation I’ve read of how cadence relates to power and efficiency. I’ve long been a fan of spinning a fairly high cadence, but never really thought much about how it affects pedalling efficiency.
Even though you may lose some efficiency at high cadence and stress your cardio system more, I think within reason this is preferable to the increased muscular fatigue you get at low cadence, especially on a hard all-day ride. Your cardiovascular system can recover very quickly, but once muscle fatigue sets in you are pretty much done for the day!

My current default cruising cadence is now up in the mid-high 80s and I’m pretty comfortable spinning at up to 100 rpm for extended periods. But I think I will keep working on nudging these figures upward. This also makes me think compact road bike gearing is still pretty tall for extended climbing in steep terrain. Even with a 34/34 ratio I often find myself forced into an uncomfortably low cadence on alpine climbs. Even the Pros looked to be over-geared on those brutal Vuelta climbs at the weekend! Modern MTB gearing seems to be ahead of the curve in that respect, allowing a comfortable cadence on any rideable slope.

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Really interesting and detailed post, thanks Sir @Coach.Mac.C

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Thank you sir drill seargant sir … @Coach.Mac.C

Seriously - thanks - great explanation of how it works !

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Thanks Coach, good insight…
I did Map 10x2 the other day which was scheduled outside but deliberately did it on trainer enabling better control of cadence. I wasn’t feeling great going into it especially being my weakness. Keeping at 100 cadence on the first few sets I’m convinced got me through. Then yesterday I had 3 and half hour endurance zone 2. Mixed cadence of 70-80 and 90 to make sure as many muscles as poss were given a ride out.
Breathing, relaxing upper body and CADENCE, MATTER.
Onwards and Upwards.

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I myself have seen this effect on a trainer. When I keep my max cadence (140), my HR goes up much, even if the power is low.

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Holy crap! This is just what I needed to read to motivate me to do the high cadence novids :scream: All joking aside, makes a lot of sense.

One question: last time I tried to hit max cedence I hurt something on the side of my knee, so I stopped going for max cadence and stuck to the highest I could reach without bouncing too much (about 140 rpm for me). Am I missing out on the benefits by avoiding going all out?

Thanks.

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Great article, yet again. Best I’ve seen to explain the importance of cadence work. I’ve certainly notice a difference during my time I Sufferlandria from initially being at mid 80’s to now spinning well in the 90’s. For me my cadence now automatically increases when hitting FTP/MAP blocks, often to 100+. I used to blame this on my puny legs and presumed I had low muscular endurance (may be true) but now I can try to convince myself that I’m efficient instead :rofl:

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Great read and explains my cadence journey on the Sufferfest well!

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Good explanation of why high cadence matters. I’ve tended to focus on power and attend to cadence targets only when convenient but at the same time knew that robbed me of the poorly understood (by me) benefits of high cadence. With this article, there are no more excuses.

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I used to go all out in the cadence workouts. However, in my last cadence workout, I found that I was doubling over and pushing on my handlebars in order to get enough leverage to get over 130rpms. The result was that I ended up pushing so hard that my saddle ended up pointing down at a 30 degree angle. Before I do those again I think I need a new saddle clamp. :frowning::pleading_face:

I use the 1st as a bit of a warm-up but still challenging and then all out on the rest of them. Usually my second build or hold is the highest and they start going downhill from there.

Great article, I really enjoyed it. When I joined my 1st cycling club, one of the first runs was a special, annual 200 miler. I put the bike in 54*11 and hardly changed gear all the way, I even climbed in it. My theory at the time was my trailing leg always had a bit of recovery between grunts, and as the others were pedalling at treble my cadence, they would surely tire first. How times have changed

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I find these sessions the hardest to motivate myself through. This explanation really helps. Excellent!

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Thanks. The article was useful indeed and now I’m gonna pay more attention to such kind of exercises :slight_smile: however, I discovered this “life hack” with higher (90+) cadence naturally by myself few years ago while doing a triathlon!) so my body has found this “method” naturally I guess in order to save muscles power for the final (running) stage. And this point I think is important: many of you say the high cadence increases BPM at too high level which affects worse than burned out muscles. Yes, I do agree. However I believe that usage of this kind of trick needs a cold head as usual : I mean you can play with higher cadence to improve your final power outcome, in the meantime you need to find this golden middle point. And this balanced point is very personal thing I belive could be found by imperic way, from training to training. That’s my point :slight_smile:

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my pedal upstroke on my left is lighter than my right.

whereas pedal downstroke on my right seems heavier than my left.

I’m trying to correct this habit to improve my pedaling efficiency.