OnWeight · Content Design
Copy Rules
Every word in this app is the corner coach talking. Between rounds, on a phone, to someone tired and cutting. Say the one thing that changes their next move, then get out of the way. This is the standard that keeps the writing sharp instead of soft.
01 Who's reading
Write for one person, not a marketing persona. They are a combat athlete mid-cut: dehydrated, hungry, training twice a day, checking the app before a fasted morning weigh-in or last thing at night. They are an expert in their sport and a novice in nothing that matters to them.
They know fight languageCut, camp, walk-around, weigh-in, gas tank, rounds, division. Use it. Explaining it is condescending.
They don't know physiologyPlasma osmolality, RED-S, glycogen. Translate it to weight, water, power, recovery: what they feel.
They're skimming, not readingEyes hit the headline and the number. Body copy is glanced, not studied. Reward the glance.
The stakes are realMissing weight loses the fight and the purse. Calm confidence reassures; hedging and alarm both erode trust.
02 The voice: corner coach
One voice across the whole app: a good coach who happens to know the numbers. Direct, never harsh. Certain, never hyped. The app's job is to interpret the scale in plain language; the voice is how it earns the right to.
Plain over cleverNo wordplay, no puns on punches. Clarity wins every time it competes with personality.
Calm under pressureEven when delivering bad news (too fast, off pace, missed) the tone stays level. The coach doesn't panic.
Earns trust with specifics"+0.8 kg in your luteal week" beats "you may notice changes." Real numbers prove the app reasoned about them.
Coaches, never scoldsBehind pace → "tighten this week," not "you failed." Always points at the next action, not the mistake.
03 The eight rules
R1One idea per screen.
If a screen is teaching two things, it's two screens, or one of them is cut. The title states the single idea; everything below supports it. This is the antidote to the wall of text.
R2Lead with the verdict, then the why.
The athlete wants the call first: on track, too fast, behind. State it in the headline. The reasoning is support copy underneath for the ones who want it, never the opening act.
✕Buries the call
"Based on your seven-day average and current trajectory, your rate of loss is slightly higher than the plan requires at this stage of camp."
✓Call first
You're cutting too fast.
0.9% this week, plan is 0.5%. Add a meal back.
R3Two points or more → bullets.
The single biggest fix. Any explanation with more than two distinct ideas becomes a bulleted list. Prose paragraphs of coaching read as AI filler; bullets read as a coach who knows exactly what matters.
✕Paragraph (real, before)
"A 4.6 kg cut over 8 weeks is about 0.7% of bodyweight a week, right in the safe zone and well under the 1% ceiling where muscle starts to go."
✓Bullets (after)
Your timeline is comfortable
- 4.6 kg to lose over 8 weeks
- About 0.7% of bodyweight a week
- Well under the 1% ceiling where muscle goes
Bullet discipline: one idea each · lead with the number or verb · ≤ 9 words · no full stops · parallel grammar · 2–4 per tip, never more. If you need five, the tip is doing two jobs (see R1).
R4Speak fight, not physiology.
Use the sport's words; translate the science. Jargon the athlete owns builds credibility. Jargon they don't sends them to Google, or to a competitor.
✕Lab coat
"Acute reduction in total body water via hypohydration protocols may transiently impair power output."
✓Corner
"Cut the water too hard and you walk in drained, not dangerous."
R5Cut every word that isn't load-bearing.
Each word earns its place or it's gone. Kill throat-clearing ("In order to…", "Please note that…"), hedges ("might possibly," "it's worth mentioning"), and restating the obvious. Then obey the budgets in §4.
✕17 words
"In order to complete your setup, please go ahead and enter your current morning weight below."
✓5 words
"What do you weigh now?"
Fasted, first thing. That's your start line.
R6Buttons name the outcome.
A CTA says what happens next, in the athlete's terms. "Submit," "Continue," "OK" are banned where a real verb fits. Match the button to the moment.
✕Generic
SUBMIT · CONTINUE · OK · NEXT
✓Named
BUILD MY PLAN · LOG TODAY'S WEIGHT · USE MY NUMBER · +0.8 KG
R7Health notes: supportive, specific, never diagnostic.
On anything medical (RED-S, a lost period, a too-aggressive cut), name the real risk plainly, point to a human (coach or doctor), and label it. The app observes; it never diagnoses. Always tag "Not medical advice."
✕Diagnoses / alarms
"Warning: you may have amenorrhea, a serious medical condition requiring immediate treatment."
✓Observes / supports
A missing period isn't just a tracking gap
- It can signal low energy availability (RED-S)
- That costs bone, recovery and power
- Worth a check-in with your coach or doctor
Tone test: it should read like a coach who's seen this before and cares, not a liability disclaimer or a diagnosis.
R8One word per concept, forever.
Pick a term and never drift. "Weigh-in" is never also "weight check." Inconsistency makes an athlete wonder if two words mean two things. The lexicon in §5 is law.
04 Length budgets
Hard ceilings per slot. Under budget is fine; over is a rewrite. Count words, not characters. When in doubt, cut.
| Slot | Budget | Shape | Example |
|---|
| Screen title | ≤ 6 words | A question or a call | "How fast do you cut?" |
| Subtitle / helper | ≤ 18 words | 1 sentence, no second clause stacking | "Your fasted morning weight. That's the start line." |
| Coach-tip headline | ≤ 8 words | The verdict, stated flat | "This pace guards your gas tank." |
| Coach-tip body | 2–4 bullets | Bullets, never a paragraph | see R3 |
| Bullet | ≤ 9 words | Lead with number/verb, no full stop | "Well under the 1% ceiling" |
| Button | 1–4 words | Verb + object, outcome-named | "Build my plan" |
| Disclaimer / note | ≤ 20 words | Quiet, factual, tagged | "Based on cuts logged during camp. Not medical advice." |
| Empty / loading state | ≤ 10 words | What's happening + why | "Mapping your cut to fight day, week by week." |
05 Lexicon: one term per concept
The canonical word is on top. The struck word is banned.
Cutnot weight loss
Campnot program / plan period
Weigh-innot weight check
Walk-around weightnot normal weight
Limitthe division max, not goal / target
Targetthe body number you trend to
Weigh-in weightwhat the scale reads on the day
On tracknot on schedule / on pace
Too fastnot aggressive / excessive
Behindnot slow / off-target
Trendnot average / moving line
Lognot record / enter / track
Waternot fluid retention
Rehydratenot refuel / recover fluids
Person & tense. Address the athlete as "you," and let the app speak as "we" for the system ("we lowered your target") or "I" only in a named-coach moment ("I read your numbers"). Never mix "you" and "the user" in one breath. Default to present tense, active voice.
06 Numbers & units
- Always show the unit. "0.5 kg," "0.7% a week." A bare number makes the athlete hunt for what it means.
- One decimal for weight, one for percent. 74.4 kg, 0.5%. Never 74.40; never 0.53819%.
- Sign deltas explicitly. "+0.8 kg," "−1.2 kg." Direction is the whole point of a change.
- Round honestly, and conservatively on safety. A cut-rate estimate rounds toward the safer number, never the flattering one.
- The number is the hero; let it carry weight. Don't wrap a clean figure in a sentence that re-explains it.
07 Don't sound like a robot
AI copy isn't wrong. It's weightless. It has perfect structure and no scar tissue: the cadence of someone who read about cutting weight but never woke up at 5 a.m. spitting into a cup. These are the tells that make our screens read as generated. Hunt them.
A1Kill the "it's not just X, it's Y" reflex.
The negation-then-reveal structure is the #1 AI fingerprint. It sounds profound while saying nothing. A coach states the thing; they don't build suspense around it.
✕AI antithesis
"A missing period isn't just a tracking gap — it's your body sounding an alarm."
✓Just say it
"A missing period can signal low energy availability. Worth a check-in with your coach or doctor."
A2Don't force the rule of three.
AI pads lists to three for rhythm: "safe, smart, and sustainable." If only two things are true, write two. A padded triplet always has one weak, vague member; cut it.
✕Padded for cadence
"This pace keeps you strong, sharp, and ready to perform at your peak."
✓Only what's true
"This pace keeps your power. You make weight without gassing out."
A3Em dashes are seasoning, not the meal.
One every few screens, max. When a dash is holding two half-thoughts together, you've got two sentences pretending to be one. Use a full stop. Short sentences are the corner's natural rhythm.
✕Dash crutch
"Your water's peaking now — which is normal — and it'll ease over the next week — so don't chase the scale."
✓Full stops
"Your water's peaking. That's normal. It eases over the next week, so don't chase the scale."
A4Ban the wellness-app vocabulary.
These words signal "generated marketing copy" instantly. No fighter says them. Left is banned; right is what the corner actually says.
Unlock your potential→ make weight, keep your power
Your fitness journey→ this camp / your cut
Crush your goals→ hit your number
Take it to the next level→ tighten it up
Game-changer→ name the actual change
Seamless / effortless→ just describe it working
Empower / elevate→ help you / sharpen
We've got you covered→ say what you'll do
Dive in / embark→ start
Supercharge / optimise→ name the real benefit
Stay tuned→ coming: [the thing]
Robust / holistic→ delete; say nothing vaguely
A5Cut the throat-clearing transitions.
"It's worth noting that…", "Remember, …", "At the end of the day…", "Simply…", "Of course, …". AI front-loads sentences with filler that pretends to be a human pause. Delete the wind-up and lead with the verb.
A6Be specific enough to be unfakeable.
Vagueness is the deepest tell. AI hedges because it has no real data. We do. "You may notice some changes" is a robot guessing; "+0.8 kg across your last three luteal weeks" is a coach who watched. Reach for the real number, the real day, the real division every time.
The read-aloud test. Say the line out loud in a coach's voice between rounds. If it sounds like a brochure, a LinkedIn post, or a wellness influencer, it's AI. If it sounds like someone who's cut weight and means it, ship it.
08 Before it ships
Run every string through this. If any answer is no, rewrite.
- One idea? Could a tired athlete say what this screen is for in five words?
- Verdict first? Is the call in the headline, not buried in the third line?
- Bulleted? Anything over two points is a list, not a paragraph.
- Fight words, not lab words? Every term is one the athlete already owns, or it's translated.
- Under budget? Every slot is at or below its word ceiling in §4.
- Load-bearing only? Delete any word and the meaning survives → that word should already be gone.
- Named button? The CTA says what happens, in their language.
- Consistent? Every concept uses its one canonical word from §5.
- Coach, not scold or siren? Bad news stays calm and points at the next move.
- Medical care? Health notes observe, point to a human, and are tagged "Not medical advice."
- No robot tells? No "isn't just X, it's Y," no padded triplets, dashes rationed, no wellness-buzzwords.
- Passes read-aloud? It sounds like a coach who's been there, not a brochure.