Training with Watts: A Beginner's Guide to Power-Based Training

Speed lies. Heart rate lags. But watts don't.

A watt — one joule of work per second — is the same unit whether it's powering a light bulb or moving a cyclist up a climb. For beginners in cycling, running, and rowing, it turns out to be the most honest measure of effort available: objective, instant, and impossible to fake. This guide explains what watts actually mean in a training context, how to find your own numbers, and how to start using them to build real structure into your training.

What is a watt in training?

Power is the rate at which work is done. One watt equals one joule of work per second. In physical terms, power equals force multiplied by velocity — a formula that applies whether you are turning a bicycle crank, pushing off a track, or pulling a rowing handle.

What makes watts useful is their objectivity. A power meter measures actual mechanical output, not your body's reaction to it. Heart rate reflects a physiological response that lags behind effort by 30 to 60 seconds and shifts with heat, fatigue, hydration, and even caffeine intake — none of which the meter cares about.

Speed has similar limitations. Wind, gradient, road surface, and altitude all affect the speed you produce at any given effort level. Watts ignore all of that. Two hundred watts into a headwind represents the same workload as 200 watts on a calm day.

The unit is consistent across cycling, running, and rowing, even if the underlying mechanics differ. In cycling, power equals pedal force multiplied by cadence. In running, it reflects ground reaction force combined with pace. In rowing, it is derived from stroke force and stroke rate.

How do you work out your watts?

The most established method in cycling is a dedicated power meter. These devices use strain gauges to measure torque applied to the drivetrain — at the crank, pedal, spider, or rear hub — then combine that with angular velocity to calculate power. The technology has been commercially available since 1989 and now transmits wirelessly via ANT+ or Bluetooth to a head unit or smartphone.

For beginners, a smart trainer is often the most practical entry point. Rear-wheel and direct-drive trainers measure power indoors without requiring a separate device. Indoor bikes such as the Wattbike include built-in power measurement, though figures may not align precisely with outdoor equivalents. If you would prefer to start without hardware entirely, opposing-force models can estimate power from speed, weight, gradient, and wind resistance — less accurate, but a reasonable starting point.

Runners can use footpods such as Stryd or GPS-based estimates from Garmin, both of which capture effort on hills more reliably than pace alone. Rowers on a Concept2 ergometer have the simplest setup of all: the machine calculates power directly from stroke rate and drag factor.

For cyclists ready to invest, a mid-range pedal-based power meter — typically in the €200–400 range — is the most portable and beginner-friendly option. It moves between bikes easily and requires no specialist tools.

What wattage should a beginner expect?

Raw watt numbers vary considerably depending on body weight, fitness history, and sport. For cycling, here are approximate ranges for a rider of around 70 kg:

Watts per kilogram (W/kg) matters more than absolute watts in most real-world situations. On a climb, a lighter rider producing fewer absolute watts can outpace a heavier rider producing more — because the ratio of power to body weight determines how fast you travel uphill.

One important caveat: power figures from cycling, running, and rowing are not directly comparable. Different muscle groups, movement patterns, and mechanical efficiencies mean that 200 W in one sport does not represent the same fitness level as 200 W in another.

Average power vs. normalized power — what's the difference?

Average power is exactly what it sounds like: the simple mean of all power readings across a session. Easy to understand, and a solid starting metric. Its limitation is that it underestimates the physiological cost of variable efforts.

Normalized Power (NP), a concept developed by Andrew Coggan and Hunter Allen, addresses this by applying a weighted average that accounts for the body's non-linear response to changes in intensity. A hilly 45-minute ride might show an average power of 180 W but a Normalized Power of 210 W — reflecting how much harder the surges and recoveries actually stressed your system. The ratio of NP to average power is called the Variability Index (VI). A VI close to 1.0 indicates steady, controlled pacing; a higher VI signals frequent surges, common in criteriums or group rides.

For now, focus on average power. Introduce Normalized Power once you are reviewing ride files regularly and want a more complete picture of training stress.

How do you start training with watts? Find your FTP and set your zones

FTP — Functional Threshold Power — is the highest average power you can sustain for approximately one hour. It anchors all power-based training. Get this number right and your zones, training stress scores, and progress tracking all become meaningful.

Two tests dominate in practice. The 20-minute test has you ride all-out for 20 minutes, then multiply your average power by 0.95. The ramp test increases power by a fixed amount each minute until you can no longer continue, after which an algorithm estimates FTP from your stopping point. Most beginners prefer the ramp test — it is less gruelling. A third option is automatic detection: platforms such as Intervals.icu can estimate FTP from recent hard efforts without a formal test.

Once you have your FTP, you can set training zones. Using the Coggan 7-zone model: Zone 1 is Active Recovery (below 55% FTP), Zone 2 is Endurance (56–75%), Zone 3 is Tempo (76–90%), Zone 4 covers Threshold and Sweet Spot (91–105%), Zone 5 is VO2max (106–120%), Zone 6 is Anaerobic (121–150%), and Zone 7 is Neuromuscular (above 150%).

Research by Stephen Seiler supports a polarized approach: roughly 80% of sessions in Zones 1–2, with around 20% at Zone 5 and above. This distribution appears effective for endurance development. A practical first week looks like this — complete a ramp test, enter your FTP into a training platform, then schedule one Zone 2 ride and one threshold interval session. Re-test every four to six weeks, as advised in Joe Friel's periodization framework, to keep your zones accurate.

If designing sessions manually feels overwhelming, PlanWatts connects to Garmin, Strava, or Intervals.icu, reads your FTP and current fitness state, and generates zone-based workouts automatically — a useful option for beginners who want structure without having to build it from scratch.

Watts in cycling vs. running vs. rowing

Cycling has the most mature power ecosystem. Power meters are widely available at multiple price points, FTP is the accepted reference standard, and watts measure mechanical output directly at the drivetrain. The coaching frameworks built around this data are well established and widely tested.

Running power is newer and less standardised. Devices such as the Stryd footpod or GPS-based estimates from Garmin capture effort on hills more accurately than pace alone — a genuine advantage for trail and road runners. Stryd uses Critical Power as its equivalent of FTP. Power zones for running exist, but no single universal standard has emerged yet.

Rowing sits in a different position. The Concept2 ergometer calculates power directly and consistently, with 500-metre split time mapping to watts via a fixed formula. Because conditions on an ergometer are controlled, power figures are highly comparable across athletes — something neither cycling nor running can fully claim outdoors.

The key rule: never compare absolute watt numbers across sports. A 200 W cyclist and a 200 W runner are not equally fit. Mechanical efficiency, muscle recruitment, and movement economy differ too much between disciplines for the numbers to translate directly.

Key takeaways

Watts measure work rate directly and objectively — unaffected by wind, gradient, temperature, or how you slept. Power meters have been commercially available since 1989 and now cover cycling, running, and rowing in various forms.

W/kg matters as much as absolute watts. Find your FTP using a ramp test or platform estimation, set your zones with the Coggan model, and build your week around mostly Zone 2 work with occasional high-intensity efforts. Re-test every four to six weeks to keep those zones current.

Cycling offers the most complete power-training infrastructure. Running power is useful but still developing as a standard. Rowing on a Concept2 provides some of the most consistent power data available in endurance sport. Whichever discipline you train in, watts give you an honest, trackable number to build progress around.