Chapter 04Field Notes
The science behind your riding, one principle at a time.
Same ride. Different impact.
Chapter 03 told you which engine a ride hit. Relative Load tells you how hard you hit it. An Endurance ride can be a light Maintain dose or a heavy Overload dose of the same engine, and the difference is measured against one thing: what you're currently built to absorb.
01 · The idea
How hard was that ride? It depends.
The engine is the what. Relative Load is the how much. Same engine, very different dose:
Endurance · 90 minutes
Touches Z2
Endurance · 6 hours
Floods Z2
- The dose is what the ride cost you overall in TSS, your fitness currency.
- What you can absorb is your Fitness, CTL (Chronic Training Load). Your recent training history, weighted toward the last few weeks, expressed as a per-day load. CTL 62 means your training has been the equivalent of about 62 TSS every day. Do exactly 62 a day from here on and it stays 62.
- Divide one by the other and you know how many normal days of that engine you just did in one go.
150
Ride costTSS
62
Your Fitness · CTL
Relative Load
2.4×
2.4 days of your fitness in one ride!
Why "relative"?
Because it's relative to your Fitness. Nobody else's.
Saturday. You're a Cat 5 who jumped in with the Cat 3 group. Same route, same speed, same surges on the same hills. You sat in the same wheel line for three hours and the head unit says 150 TSS for all of you. Then everyone goes home and the ride becomes a different ride for each of you.
You · Fitness 40
Nearly four normal days in one ride. Heavy dose. The next few mornings will show it.
The Cat 3 next to you · Fitness 95
A solid day and a half. Real dose, no dent. Back on the bike tomorrow.
Same wheel, same file, same 150 TSS. Overload for you, Build for them. That's the whole point of the word: only the ratio to your own Fitness tells you what a ride was, and that's why every ride in FORM carries both words: the engine, then the dose.
02 · What a dose does
Stress, then rest, then stronger.
A big dose knocks you down before it builds you up. Your body repairs the damage and then overshoots, so a few days later you're a little more capable than before. Rest too little and you never get the overshoot. Wait too long and it fades. This is the whole game, and it's why the size of the dose matters so much.
Supercompensation · FORM's clock
Dip, rebuild, overshoot, fade.
One ride · illustrative
The bigger the dose, the deeper the dip and the longer until the overshoot. A small dose barely dips and barely builds.
A block · how it's really done
You don't wait for the overshoot after every ride. Doses stack across a block, fatigue and all. Then the rest at the end, a recovery week or a taper, is where the adaptation gets harvested, once.
03 · How heavy was it
Six sizes of dose, from a spin to an epic.
FORM sorts every ride onto one of six rungs by how many normal days of training it contained. The rung is the second word on every ride label in your log.
Same engine. Different rung.
Primer
<0.5× CTL
Half a day's worth or less. Openers, spins, the day before a race.
Exposure
Maintain
0.5–1×
About a normal day. Keeps the engine warm. Doesn't move it.
Exposure
Build
1–2×
One to two days' capacity. The first rung that counts as development.
Dose
Overload
2–3×
A big day by your standards. Expect the body to report on it tomorrow.
Dose
Deep Load
3–4×
Three to four days in one. Form drops hard. Recovery is now the plan.
Dose
Event Load
>4×
Event-sized. A gran fondo, a stage, an epic. Days to absorb.
Dose
Everything over 1× is a dose: it develops you. Everything below is exposure: it maintains, but doesn't grow you. A week of Primer and Maintain rides is riding, not training, and FORM will say so.
Event Load describes size, not the calendar. A solo six-hour training day can be Event Load. A short crit usually isn't.
04 · The aha
Same route, same power, three different rides.
One athlete rides the same 150 TSS loop three times across a season. The road doesn't change and neither does the number on the head unit. Their Fitness does, so the same ride becomes a smaller dose each time.
March
150 ÷ 40 = 3.8×
Deep Load
May
150 ÷ 62 = 2.4×
Overload
July
150 ÷ 95 = 1.6×
Build
This is what getting fitter looks like in the log, and it carries a warning. To keep improving, your rides have to grow with you. If they don't, the same loop slides quietly down the ladder until it's Maintain, and you've stopped developing without noticing.
05 · What the coach does with it
FORM doesn't ration big rides. It watches what they did to you.
FORM has no "two big rides a week" quota. A quota treats every athlete the same, and the body doesn't: the same Deep Load costs a Fitness-95 athlete one easy day and a Fitness-55 athlete three. So the coach watches what the dose did to you, and plans the next days from that.
The gate is readiness
Tomorrow is decided by the report, not the calendar.
A Deep Load craters your Form and usually suppresses HRV. Those signals, from Chapter 02, set the next day's ceiling: red is rest or easy spin, amber is nothing above tempo. The ride itself doesn't trigger a rule. What it did to you does.
The ladder is the dial
When a session is barred, the coach steps one rung down.
Planned an Overload threshold day and woke up amber? The coach doesn't cancel. It re-plans the same session at Build. If the type itself is barred, it falls back to Endurance · Maintain and moves the hard day, not the athlete.
Deep Load · Tuesday
"Deep Load on Tuesday. Wednesday and Thursday are not a negotiation. The legs filed the paperwork. I'm just reading it back to you."
Primer · Friday
"Race Saturday. Friday is a Primer. Prime the engine, don't spend it."
Maintain · Week 3
"Five rides, all under 1×. That's exposure, not training. Your Fitness held. It didn't move."
Build · July
"Same ride as March. March called it Overload. Today it's Build. The ride didn't get easier, the engine got bigger. Adequate."
06 · The fine print
Six things that are always true about the number.
It's yours alone
Your 100 TSS and another rider's 100 TSS are unrelated facts. Only the ratio to your own Fitness compares.
It's locked at roll-out
Graded against the Fitness you had that morning. Getting fitter later never re-grades an old ride.
Type and Load never touch
What the ride was and how big it was are two separate facts. A Race can be Build. An Endurance ride can be Event Load.
Below 1× is not development
Primer and Maintain keep you. Build and above grow you. FORM labels the difference plainly.
No grade without a baseline
Under a Fitness of 20, or with no TSS, FORM shows "No/Low CTL" rather than a ratio that means nothing.
Big rides aren't rationed
No weekly quota. The morning after decides the day after, through your readiness, not a count.
Your rides aren't getting easier. You're getting stronger.
Chapter 03 named the engine. This chapter sized the dose. Together they give every ride you do a two-word label: what it trained, and how much, for you, that day. That label is Training Impact, and it's next.
Next chapter: two axes, every ride named. Training Impact, the breakthrough behind FORM.
Field Notes · Chapter 04 · Same ride. Different impact.← 03Next · Chapter 05 · More Than Hard or Easy →