Signal
EMG · Biceps
Live
100%
Very high recruitment
See the muscle work
Live muscle activation and a real EMG trace, the moment you start the set.
40 units · Australia · 1 Sep 2026
·
0 of 40 reserved
Train the muscle.
Not just the movement.
Meet ZELOS One — Z1 for short. A coin-sized sensor that reads your working muscle directly, so you can see how hard it worked, beat your historical best, and watch real strength build. Strength, running, cycling.
—d —h —m —s
to launch
Live signal
EMG · 1 kHz
Streaming to your phone & watch
Your muscle
Z1 reads it1,000×/sec EMG · 200×/sec motion
Phone & watch
How it works
ZELOS One reads the muscle directly.
A coin-sized sensor and a skin-safe adhesive. It reads your muscle’s electrical activity and motion a thousand times a second, and streams it live to your phone and Apple Watch.
-
01
Am I using the right muscle?
Live activation and recruitment, the moment you start the set.
-
02
Was that set productive?
Set quality, stimulus and estimated fatigue, scored every set.
-
03
Push, rest, add weight, or stop?
Real-time coaching from what the muscle is actually doing.
-
04
Am I actually getting stronger?
Trends across sessions and weeks — progress you can see.
Everything the muscle is telling you
Z1 reads the working muscle directly — so every rep, set and session becomes something you can actually see, score and act on.
Quality
Set 3
Bench Press · 60 kg × 10
Set quality
Reps to failure
Activation86%
Fatigue38%
Load1.2K
Productive set — weighted to your goal · Hypertrophy
Know if the set counted
Every set scored 0–100 from how close you trained to failure, how fast you fatigued, and how hard the muscle worked — then weighted to your goal.
Strength
Strength Index
118
+18
Baseline
100
100
Apr 2Apr 23May 14Jun 18
Watch real strength build
A per-exercise Strength Index where 100 is your baseline — real strength trend without waiting on bodyweight.
Coach
Coach · Now
Reading
End sets at 0–3 RIREffort target
PUSH
Add 2.5 kg next sessionLoad progression
+LOAD
Rest 90s — readyRecovered to baseline
GO
Know what to do next
Plain coaching from what the muscle is doing — when to push, rest, add load or stop.
Progress you can see
Beat your best — rep by rep, week by week.
Z1 holds your historical best as a live benchmark, then shows you where today lands — inside the set, and across the month.
Rep Effectiveness
Set 1
Peak output, rep by rep
vs all-time bestNew peak · rep 8
Within the set
Output, rep by rep — against your best
Every rep's peak output, plotted live against your all-time best line. A breakthrough — or an off day — shows up mid-set, not weeks later.
Exercise Comparison
Bench Press
Past month
3 months
All-time
New peak — beat your past-month best.
Historical bestBeatBelow
Across the weeks
Every lift vs your past month, 3 months & all-time
Switch the window and see exactly where today's session sits against your own history — green when you've beaten it, grey when you're below.
One sensor, three ways to train
Strength. Running. Cycling.
Move Z1 to the muscle that matters. The signal follows the work.
Strength · hero
Train to stimulus, not soreness
Live activation, set quality, estimated RIR, set-to-set and vs-PB, weekly stimulus and load progression.
Running
Is it your legs or your lungs?
Place Z1 on your quads, calves or hamstrings to read local muscular fatigue — alongside the heart rate and pace from your watch.
Cycling
A fresh-legs readiness signal
The same local-fatigue read on your quads and glutes — next to cadence and power, not instead of them.
Run and cycle are one more input for muscular fatigue — not a replacement for heart rate or power.
The device
Small enough to forget.
Smart enough to coach you.
- ~4 × 2 cmpocket-coin small
- 1,000×/secreads muscle activity
- 200×/secreads motion
- All-daybattery, live fuel gauge
- BLEBluetooth Low Energy
- OTAgets smarter after you buy
- Skin-safeadhesive interface
- Matte whitepremium finish
Three steps
From sticker to insight in seconds.
- 1
Stick it on
Place Z1 on the muscle you're training.
- 2
Train normally
Z1 detects your reps and sets automatically.
- 3
See the work
Live as you lift, and the trends after.
Why you can trust the number
Lab-grade signal. Consumer simple.
Under the hood, Z1 runs the kind of signal processing used in movement labs: band-pass filtering to isolate real muscle signal, spectral methods that track fatigue more reliably than raw amplitude, and per-user calibration so your numbers are comparable session to session — fused with motion for context.
You never see the raw EMG. Just the decision.
Why I built ZELOS
I'm a doctor in Melbourne. Every day I watch people train hard and still plateau, because the one number that matters — is the muscle actually doing the work — is invisible. Wrist wearables can't see it. So I built the thing I wanted: a sensor that sits on the muscle and tells you the truth, set to set.
Z1 is the first run. Forty of them. I'd love you to be one of the first to train this way.
Kaveshan NaidooFounder, ZELOS Fitness
The drop
40 units. Australia.
One run.
This is the first production run of Z1 — 40 units, shipping Tuesday 1 September 2026, to Australia only. When they're gone, the next run isn't scheduled.
40 of 40 remaining
—d —h —m —s
What's in the box
- Z1 sensor
- 10 skin-safe adhesive pads
- Magnetic charger + USB-C cable
- The ZELOS app — iPhone + Apple Watch
Founding 40
A numbered unit · the full ZELOS app included · a direct line to the founder.
You're #— of 40.
Check your inbox — we've saved your founding spot. We'll be in touch the moment your Z1 is ready to ship.
Know someone who trains seriously? Send them the page.
Questions
Good to know.
Do I need a subscription?
No — there's no subscription. Every feature, from live activation and automatic rep and set counting to analytics and coaching, comes with your Z1 and the ZELOS app.
Does it work with Apple Watch or Garmin?
Z1 pairs with your iPhone and Apple Watch today, and complements the heart rate, pace and power you already get from your watch. Broader Garmin support is on the roadmap — Z1 adds the muscle layer those devices can't see.
How does it attach? Is the adhesive reusable?
Z1 sits on a skin-safe adhesive pad over the target muscle. Your kit includes a starter pack of pads; pads are a consumable you replace as needed for the cleanest signal.
Is it accurate? How is it different from a fitness tracker?
A wrist tracker measures your body from the outside — heart rate, steps, motion. Z1 reads the working muscle directly with surface EMG, then turns it into simple, calibrated numbers. Like any wearable signal, readings are estimates and depend on good placement — but they're a signal no wrist device can give you.
Strength only, or run and cycle too?
All three. Strength is the most mature experience; for running and cycling you place Z1 on the working leg muscles to read local muscular fatigue as one more input alongside heart rate and pace.
Do I need an iPhone?
Yes — the launch app is built for iPhone and Apple Watch.
Shipping & returns
This first run ships to Australian addresses only, from 1 September 2026. Reserving today places no charge and carries no obligation — you confirm your order when units are ready.
Is this a medical device?
No. Z1 is a fitness and performance product. It is not intended to diagnose, treat, cure, or prevent any disease.
Train the muscle.
Not just the movement.
40 units. Australia. Ships 1 September 2026. When they're gone, they're gone.
Reserve your Z1 — A$29940 of 40 remaining