This article was first published in Rouleur Issue 141. Rachel Neylan is a former professional cyclist, Olympian and World Championship silver medallist, and a qualified physiotherapist. Having recently completed an MSc in Coaching Psychology, she now works at the intersection of elite sport, human performance science and leadership, advising athletes, executives and organisations on how to build performance that endures. www.rachelneylan.com
Walk into any café stop today and you’ll hear it before you even unclip:
“What were you holding up that climb?”
Not speed. Not heart rate. Watts.
Power has become the default language of modern cycling, part metric, part identity, part performance currency. It is the number that supposedly reveals everything: how strong you are, how fit you are, how fast you should be.
My first real introduction to power came early, in the infamous ‘gold medal factory’ lab – the South Australian Sports Institute. Gary West stood behind me, eyes fixed on the monitor as I sweated through another set of intervals on the old SRM ergometer. No distractions. No wind or scenery to lie to me about how hard I was working. Just me, the pedals, and the unforgiving truth of watts climbing (or falling) across the screen.
“Hold it,” Gary would say. “Five more seconds at 320.”
Those sessions were brutal. But they were also revelatory.
For the first time, I understood exactly what my body could produce, where my limits were, and crucially, how to push them systematically. Power transformed cycling from guesswork into engineering.
But years later, I’d learn its seductive danger too, the risk of letting the number override every other signal, of trusting the screen more than the screaming in my legs. Power gave me accuracy and focus. It also taught me that precision without awareness is just sophisticated guesswork.
This is the story of power in cycling, the science, the revolution, and the subtle risks that come with seeing the sport through the lens of watts.
The physics of effort
Cycling is a sport defined by illusions. Speed flatters on descents. Heart rate lags behind effort. Perceived exertion is shaped by sleep, stress, caffeine, and mood. Power cuts through all of that. Power is the truth beneath speed. In physics, power equals work done over time. On the bike, that becomes force on the pedals multiplied by how quickly you apply it.
It is the purest expression of metabolic effort available outside a laboratory. Every watt is a tiny piece of biochemistry made visible, a fusion of muscle fibres, oxygen delivery, neuromuscular recruitment and fuelling, translated into a number you can see on your handlebars.
Push 300 watts on a calm day after a solid night’s sleep and you might fly up the climb, legs turning over smoothly, breath controlled. Push the same 300 watts into a headwind after three hours of broken sleep, and you’ll feel like you’re pedalling through concrete, every revolution a negotiation with your screaming quads.
The watts haven’t changed. Everything else has. Where speed tells you what happened, power tells you why.
Rachel Neylan is an ex-pro cyclist
The man who saw force where no one else was looking
Before the mid-1980s, cyclists trained with nothing more than feel, heart rate, and folklore.
Speed charts. Stopwatches. “Ride hard on Wednesday.”
In 1986, a German engineer named Ulrich Schoberer quietly changed everything.
Schoberer built the first device capable of measuring a rider’s actual mechanical output in real time: the SRM powermeter. It didn’t just record effort, it revealed it.
Instead of guessing intensity or reverse-engineering performance, the sport suddenly had a window into the one thing that mattered most: how much energy a rider could turn into forward motion.
What applied physics gave cycling was not a gadget. It was a new operating system.
SRM became the gold standard, the training bible of world champions, the backbone of performance modelling used from the Tour de France to Olympic programs. Modern coaching, pacing science, and interval prescription are all descendants of that first crankset.
Why power matters even more today
cycling has never been faster, younger, more explosive, or more data-rich than the present moment. In this environment, power isn’t a luxury, it’s survival.
Training has become a science of precision. FTP, critical power, VLamax and W are all built on power data. Without it, you’re operating on feel alone, which works until it doesn’t.
Racing is structured around wattage. Teams pace climbs and time-trials by power targets, not feel. Watch the Tour de France and you’re watching split-second calculations of sustainable output playing out at 60 kilometres per hour.
Workload management is non-negotiable. Without power, you’re guessing at training stress, and guesses don’t win races or prevent burnout.
In short: the sport has moved from intuition to quantification to ruthless optimisation.
Power is the backbone of that shift.
The power paradox
Power is objective, humans are not. Somewhere in the rise of data, cyclists began to risk outsourcing self-awareness to a number on a screen. The dark side of precision is blindly riding to the number not to the body, chasing targets, not sensations, trusting the metric, ignoring the message.
The data can’t tell when you’re at altitude, dehydrated, underslept, preoccupied, or emotionally flat. Your body whispers these truths constantly – tightness in the chest, heaviness in the legs, a flatness in your pedal stroke, critical sensations that no amount of willpower can mask.
But often we learn by default to override those whispers in service of the number, not the body. That’s when overreaching and pushing limits with a numbers only approach can become dangerous, the risk is then the body breaks down faster than it can rebuild. The problem isn’t power. The problem is thinking power is the whole truth.
Power is only one chapter in the metabolic story
To understand performance fully, you need three layers working together:
- Power: the external load – What you’re producing mechanically, the demand on the system.
- Heart rate: the internal load – How hard your body must work to meet that demand. This is where fatigue, heat stress, hydration status, sleep, and recovery show up. It’s the bridge between the watts you’re producing and the physiological cost of producing them.
- Environment: the contextual load – Heat, humidity, altitude, wind, cold, fuelling, stress, terrain.
All of these shape the relationship between power and heart rate.
Power without heart rate is incomplete, and heart rate without environmental awareness is ambiguous. Together, they tell the whole truth about your physiology.
That’s why some days 200 watts feels like floating – smooth, sustainable, almost meditative. And others it feels like dragging a refrigerator up a wall into a headwind, every pedal stroke a small act of violence against your own body. The numbers haven’t changed, you have.
The future of cycling performance
Elite sport is becoming more human again as teams recognise athletes as valuable long term assets. The best riders today use power as a tool, not an identity. They train with numbers but combine that with instinct. They monitor metrics, but listen to the body. They understand that watts show output, but awareness preserves longevity.
I learned this watching Marianne Vos prepare for the Paris Olympics, picking her as a favourite. Yes, she had all the data. Yes, she tracked her power meticulously. But in the critical moments, when to push, when to hold back, and when to trust a breakaway, she relied on years of cultivated awareness. The power meter informed her decisions, it didn’t make them. This is what world class cycling looks like.
The riders who thrive long-term aren’t the ones who blindly worship the data, or completely reject it. They’re the ones who’ve learned to hold two truths simultaneously: that power reveals what intuition cannot see, and that intuition perceives what power cannot measure.
Cyclists don’t chase watts because they love numbers. They chase watts because they are chasing understanding of themselves, their limits, their potential. Power illuminates the path, but intuition keeps us on it. And somewhere between the two, modern cycling finds its rhythm.
