PSTS: Why Power Alone Doesn’t Explain How Fast You Actually Ride
By Ric Stern
Cyclists love power because it feels objective. Watts are clean, repeatable, and reassuringly numerical. If your FTP goes up, you expect to go faster. If your MAP is high, you assume you’re quick.
But anyone who has raced, ridden fast group rides, or spent time coaching knows this isn’t always true.
Two riders can have the same FTP and ride at very different speeds. A lighter rider with fewer watts can ride away from a heavier rider with more. Someone with an “average” power profile can be devastating in the real world, while another rider with impressive test numbers struggles to translate them into speed.
That gap between engine and outcome is exactly what PSTS is designed to describe.
What PSTS Is Actually Trying to Do
PSTS stands for Performance Speed Translation Score.
It’s a composite score that combines:
power output (either MAP or FTP),
body mass,
and aerodynamic drag (CdA),
to give a single number that reflects how effectively your physiological engine can turn into real-world speed. It’s not a race predictor. It doesn’t tell you how long you’ll last, how tactically smart you are, or whether you’ll win. What it does do is answer a much more practical question:
Given this engine, in this body, in this position — how much speed potential is there?
That’s a question power alone cannot answer.
Why Watts (and Even W/kg) Fall Short
Raw watts ignore body size. Watts per kilo improve that, but still ignore aerodynamics — which dominate speed once you’re above low climbing speeds.
Two riders both riding at 4.5 W/kg can have very different drag profiles. One sits compact and efficient. The other rides tall, wide, and exposed. On the road, they are not equal. PSTS exists to sit between physiology and physics. It doesn’t replace FTP or MAP — it contextualises them.
MAP PSTS vs FTP PSTS
PSTS can be calculated using either MAP or FTP, and the distinction matters.
MAP PSTS reflects your ceiling: how much speed potential your maximal aerobic engine could produce when fresh.
FTP PSTS reflects your sustainable speed potential — what you’re likely able to express repeatedly or for long periods.
Looking at both together often explains things riders feel but struggle to articulate:
why someone feels “fast but fragile”,
why another rider grinds people down despite modest peak numbers,
or why FTP improvements don’t always show up on the road.
Reference Ranges (Context, Not Targets)
As a rough guide, PSTS values tend to fall into broad bands:
Female masters 40+ racer: 40+
Male masters 40+ racer: 75+
Female WorldTour professional: ~95+
Male WorldTour professional: ~110+
At the extreme end, the highest MAP PSTS I’ve seen comes from a World Champion, who produced a MAP PSTS of around 170.
These numbers are contextual, not aspirational. They exist to anchor understanding, not to create another leaderboard.
Why This Matters for Masters Riders
As we get older, chasing watts becomes a blunt instrument. Large power gains are harder to come by, but speed improvements are still very achievable.
PSTS highlights three levers you can actually pull:
increasing usable power,
reducing unnecessary mass,
and improving aerodynamics.
Often the biggest gains come from the last two — areas many riders under-prioritise because they don’t show up clearly in traditional power metrics. This is also why some masters riders plateau despite “training hard”. The engine may be improving marginally, but translation into speed isn’t.
If you want to see how your own power translates once body size and aerodynamics are accounted for, you can calculate your MAP PSTS and FTP PSTS using the free calculator on the site.
It’s designed to provide context — not judgement — and to highlight which limiter is actually worth addressing.
→ Check your PSTS using the free calculator
What PSTS Is Not
It’s important to be clear about what PSTS does not do.
It doesn’t tell you how durable you are.
It doesn’t replace FTP for training prescription.
It doesn’t account for tactics, drafting, or race craft.
It’s a lens — one that explains why two riders with similar engines can experience very different outcomes once wheels hit the road.
Used properly, it stops you chasing the wrong thing.
From Insight to Action
For coaches, PSTS helps guide decisions about where gains are most likely to come from. For self-coached riders, it provides a sanity check: is more power really the answer here, or is translation the issue? That distinction becomes increasingly important over 40, when recovery is precious and training time finite.
If PSTS helped clarify where your speed actually comes from, there are three ways we work with riders:
Training Plans – structured, progressive plans if you want clear direction without ongoing coaching.
The Collective – group coaching, education, and ongoing support for riders who want to understand their training, not just follow workouts.
1-to-1 Coaching – personalised planning and analysis if you want everything built around your physiology, goals, and life constraints.
Choose the level of support that fits where you are now — not where you think you should be.