.ai
AI Training That Adapts
to Your Life
Periodized programming that reprograms when your schedule, equipment, or energy changes.
No credit card. Full access. Your feedback shapes the product.
Training plans break.
SinewFit adapts.
Without SinewFit
- ✕Miss Monday's workout — your whole week is off track
- ✕Hotel gym on a work trip? Your program doesn't care
- ✕Same weights week after week — no idea when to progress
- ✕Soreness piling up but the program pushes through anyway
With SinewFit
- Miss Monday? Your plan shifts to Tue-Wed-Fri automatically
- Traveling? Get a dumbbell-only or bodyweight session for that day
- Hit 3x8 at 135? Your coach says "Add 5 lbs next session"
- Sore and fatigued? It programs a deload before you burn out
How it works
Tell us about your training
Experience level, equipment, goals, injuries, schedule
Get your first training block
AI generates a full periodized plan with coaching rationale
Train and log
Smart weight cues, set-by-set tracking, real-time progression
Adapt every week
Rate your week, give feedback, get an updated plan that builds on what you did
See it in action
Tell it about your week
Get a plan that fits
Log sets with smart weight cues
What you get
Intelligent programming that actually progresses you, and the flexibility to handle real-world chaos.
Real Periodized Programming
Full training blocks with mesocycle structure, progressive overload, and deload timing. Not a random workout of the day.
Adapts When Life Changes
Hotel gym? Schedule shift? Missed a day? The AI reprograms your week around what actually happened, not what was supposed to happen.
Progressive Overload Engine
Tracks every set. Calculates estimated 1RM. Knows when you're ready to go heavier and recommends the exact jump.
Fatigue-Aware Recovery
Detects overreaching from your ratings, soreness, and completion patterns. Programs deload weeks before you burn out.
Strength + Cardio Together
Pace targets from your mile time. Interval structure. Distance progression. All programmed alongside your lifts.
Built for the Gym Floor
Plate calculator, warm-up ramps, rest timer with haptics, one-tap set logging. Designed to be used mid-set, not just on the couch.
Built on the most capable AI available for complex planning and multi-constraint reasoning.
Why I built this
I work in professional services with unpredictable hours and regular travel. I've trained for years — run real programs, understood the science — but every plan I followed broke the moment my schedule changed.
Miss two days because of a deadline? The app doesn't care. Stuck in a hotel gym? Tough luck. Only free during nap time? Not the app's problem. Same program, same weights, same schedule that stopped working weeks ago.
So I built SinewFit. An AI coach that reprograms your week based on what actually happened — not what was supposed to happen. Whether it's work travel, childcare, a busy season, or just life — it adapts so you don't have to start over.
— Sean, Founder
support@sinewfit.aiFor anyone who wants structured training
that actually fits their life
Whether you've been lifting for years or just getting started, SinewFit builds a real program around your goals, experience, and schedule — then adapts it when things change. Strength, hypertrophy, cardio, body recomp, general fitness. Full gym, home gym, or bodyweight only.
Use it like a native app
After you sign in, most phones will prompt you to install SinewFit automatically — no app store needed. Works offline for logging.
Install manuallyHide manual steps
iPhone / iPad
- Open sinewfit.ai in Safari
- Tap the Share button
- Tap Add to Home Screen
Android
- Open sinewfit.ai in Chrome
- Tap the menu (three dots)
- Tap Install app
Help us build this.
We're looking for people who want to stress-test SinewFit and help shape the product. Whether you're experienced or just getting started — if you want structured training that adapts, we want your feedback.
Not ready to sign up? Get notified when we launch.