Back in my early racing days, we mostly trained on feel, maybe heart rate if we were fancy. These days, power meters have changed the game. Training with power data is one of the biggest leaps forward in cycling coaching – but it can also overwhelm you with numbers if you’re not careful.

As someone who transitioned from old-school training to modern data-driven methods, I’m here to cut through the noise and give you a blunt guide to power-based training. No gimmicks, just what actually works to make you faster using those wattage numbers.

Why Train with Power?

A power meter is essentially a truth meter. Unlike speed (which is affected by wind, hills, etc.) or heart rate (affected by fatigue, caffeine, temperature), power is an objective measure of your effort – the raw watts you’re putting into the pedals.

Having a power meter is like unlocking a new level of insight into your fitness. It tells you exactly how much work you’re doing, allowing you to train with precision.

For example, if you hold 200 watts for 10 minutes today, you can directly compare that to 200 watts for 10 minutes next month – no hiding from whether you improved. Power doesn’t lie.

This objectivity is gold for guiding training. Personally, once I started using power data, it highlighted weaknesses I didn’t realize I had (like my sustained threshold power needed work compared to my short sprint). It also prevented me from kidding myself on easy days – if my plan said recovery ride under 150W, I couldn’t cheat it without seeing the numbers.

In short, training with power lets you quantify your workouts and progress in a way nothing else can.

Key Metrics: FTP, Watts/Kg, and More

Power training does come with its jargon. Let’s demystify a few key terms (no fluff, just the basics you need):

Functional Threshold Power (FTP)

Arguably the most important number. It’s roughly the max power you can sustain for about an hour (some define it with a 20-minute test and minus a bit). Think of FTP as your cycling “speed limit” for longer efforts. Many training zones are defined as percentages of FTP. Increase your FTP, and you’ll likely see gains in time trials, climbs, and fast group rides.

Watts per kilogram (W/kg)

This is your power relative to body weight. It matters for climbs – lighter riders with high W/kg fly uphill.

If you’re 75kg with a 300W FTP, that’s 4 W/kg. If you drop to 70kg with the same FTP, suddenly ~4.3 W/kg – a meaningful difference on hills. Don’t obsess about comparing to others, but it’s a useful benchmark for yourself (and a reminder that losing excess weight can help performance if done safely).

Training Zones

Coaches break training into zones (often 1 through 7 or similar) based on intensity relative to FTP:

Zone 2: Endurance (easy-ish all-day pace, maybe 55-75% of FTP)
Zone 4: Threshold (~95-105% of FTP)
Zone 5: VO2 max (>106% FTP, very hard)

Power makes hitting the right zone straightforward – if my workout calls for Zone 5 intervals at 320W, I aim for that number each interval.

TSS, CTL, and ATL

These come from platforms like TrainingPeaks:

TSS (Training Stress Score): Gives each ride a score based on duration and intensity
CTL (Chronic Training Load): Like your fitness “score” averaged over weeks
ATL (Acute Training Load): Your recent fatigue

They’re useful to track if you’re into data, but if that sounds too much, you can get a lot out of power training without diving deep into these.

My advice: Learn gradually. Start with understanding FTP and basic zones, and use the others as needed.

Structuring Workouts with Power

One of the best things about power training is structured workouts. Because you have clear targets, you can design sessions to work on specific abilities. A few examples from my coaching toolkit:

Threshold Intervals

Example: 2 x 20 minutes at 95-100% FTP (with 5-10 min easy between)

Bread and butter for raising your FTP. Hard but doable; you’ll know you paced right if you’re hanging on in the last few minutes of each interval.

VO2 Max Workouts

Example: 5 x 3 minutes at ~115% FTP, with 3 min recoveries

These hurt, but they boost your top-end aerobic capacity and make hard surges feel easier over time.

Sweet Spot Training

Example: Around 88-94% of FTP, often for longer intervals like 3 x 15 min or 2 x 30 min

This “sweet spot” gives a lot of bang for buck in fitness gains without as much fatigue as true threshold work. I did loads of sweetspot in my training days and it really builds a strong base.

Sprint/Anaerobic Work

Short 10-30 second full-gas efforts (Zones 6-7) to improve your sprint and high-end power. Use your max power numbers as reference and try to beat them over time. Fun fact: seeing your wattage peak on a sprint (say 1000W, 1100W, etc.) can be super motivating – it’s like a high-score to beat next time.

Endurance Rides

Keeping an eye on power can ensure you actually stay in the intended zone. Many riders go too hard on easy days – power will call you out. If your plan says 60% of FTP and you’re creeping up to 75%, you’ll see it and (hopefully) back off. This helps prevent burnout and overtraining.

By structuring training with power, you make every session count. It’s like having a coach on your handlebars saying “go harder” or “ease up” in real time. Over weeks and months, this precision adds up to significant improvements.

Tracking Progress and Adjusting

Another great use of power data is tracking your progress. Do an FTP test every 6-8 weeks (or use a hard 20-minute effort from a race or group ride) to see if your number is rising. It’s rewarding to see watts go up – proof that your training is working.

But also watch for trends in your regular rides:

Maybe you notice you can now hold 250W in a 10-minute climb that used to destroy you at 230W
Or your heart rate at your steady 200W pace has dropped over time (sign of improved efficiency)

These little wins show you’re getting fitter. If progress stalls, that’s a cue to tweak your training – perhaps you need more rest, or a new stimulus like adding VO2 max work or increasing volume slightly.

Beware of Becoming a Slave to Numbers

Power is a tool, not the end-all. I tell my athletes to use it for guidance, but we still care about feel. Some days your target power might feel impossible – could be fatigue; maybe back off. Other days you feel awesome and exceed your planned watts – great, roll with it (within reason).

The data should inform your training, not dictate it blindly. Over time, you’ll also learn your personal quirks (for instance, some riders have a higher anaerobic capacity, so they test with an inflated FTP via a 20-min test – they learn to adjust intensity a bit lower for longer efforts).

Don’t Get Overwhelmed by Data

It’s easy to get lost in the weeds with power data. I’ve seen riders (and coaches!) disappearing down rabbit holes of analysis – printing charts, comparing every ride, getting worried if their form line dips a few points.

Remember the basics: Consistency and hard work beat fancy analysis. Use power numbers to keep yourself honest and to structure training, but the priority is doing the training.

Tips to Avoid Data Overload:

Pick a few key metrics to follow. FTP and weekly TSS might be enough for many
Have days where you just ride by feel – maybe even don’t look at the head unit. It can remind you why you enjoy cycling
Use the data to celebrate success, not to constantly self-criticize. If your power is down one day, it could just be normal fatigue
Consult a coach or experienced friend to interpret complex data if needed

At the end of the day, the goal of power-based training is to improve real-world performance. Whether that’s finishing your first 100-mile sportive stronger, nailing a personal best up your local climb, or winning a race, the numbers are a means to an end.

Bringing It All Together

Power meters and data can seem intimidating, but they are incredible tools when used right. I went from being a rider who trained on feel (and did okay) to a coach who firmly believes in blending old-school hard work with new-school tech. The result? Data-driven improvement that you can actually feel on the bike.

If you’re in the UK and on the fence about getting a power meter – the prices have come down a lot, and even a basic single-sided meter will open up this world to you. But even if you don’t have one yet, you can still apply the principles: use perceived exertion or heart rate as proxies and keep a training log.

In true Ian Bibby blunt fashion, I’ll leave you with this: no gadget alone will make you faster. It’s the commitment to train smarter and the willingness to suffer a bit in those intervals that brings results. The power meter just lights the way.

Use the data, trust the process, and enjoy the payoff when you drop your mates on the next climb or smash your personal record in that time trial. That’s the real power of training with power.

Want help making sense of your power data? Get in touch to discuss data-driven coaching tailored to your goals.