5 reps. Near failure. Every muscle.
Build strength faster than the gym.
Logic Workout recruits your muscles to near-maximal relative mechanical tension — induced by rolling, chaotic deformation and spring forces — loading them near their own limit, all at once.
All you need is the Logic ball and the app to follow the method.
Free for 14 days
- Outsmart your muscles
- Brain-driven training
- Two hours a week
- Measured, not guessed
- Strong and hard to break
Logic vs other methods
6 ways to get strong. Compared.
Muscle grows from effort near failure. Weights take a few prime movers there in 5 reps. Unstable tools let you do lots of reps, so you rarely get there. On the Logic ball, at the right level, 5 reps take every muscle near failure.
- WeightsThe reference for max strength. Reactive demand: 3×
- TRXFine for beginners. Much worse for advanced. Reactive demand: 5×
- PilatesControl and flexibility. Strength not established. Reactive demand: 1×
- BOSULess power and speed on solid ground. Reactive demand: 8×
- Swiss ballAbout 60% less force. Reactive demand: about 8×
- Logic WorkoutAt least +15% on PRs in one month, on 2 hours a week. Reactive demand: 50×
Our measurements: wrist accelerometry (Apple Watch), jerk and Welch power spectral density, 3 axes, 2 to 12 Hz. Reactive demand is our proxy for how many muscle fibers have to work, not a count of them. The Swiss ball value is an estimate, about the same as the BOSU.
The Logic Workout app
Test. Train. Measure. Recover.
The whole program lives in the app, in English and French.
Find where you stand. Muscle by muscle.
Test yourself against the NFL Combine events, the Army Fitness Test, gym lifts and sprints — or against Logic Workout's own standards. Every result lands on one ladder and colours a body map, so the weak link has nowhere to hide. Then the app points you to the workouts that close the gap.
NFL Combine · Army Fitness Test · Logic Carryover · Logic Standard
- Injury Risk
- Healthy
- Strong
- Athlete
- Legend
Warm-ups, prep, and a session for the time you have
Activity preparation workouts for what you are about to do, whether that is skiing, climbing, running or a heavy lift. Three-minute blocks when time is short, full-body sessions when it is not, and a progressive library that keeps scaling — the limiter shifts from balance to the prime movers as you get better, so the same exercise keeps working.
English and French.
Every session, measured
Apple Watch integration gives you a real-time Logic Effort Score, so you can see the effort a session actually demanded rather than guessing from how it felt. Stability and consistency are tracked alongside it, and every workout is logged against a weekly goal.
Out of chronic pain, back to strength
Logic began in rehabilitation. In the recovery cohort of our first preprint, participants rebuilt after injury and years of chronic pain with short, low-load reactive sessions — and reported their pain resolved and strength and function regained. The same stimulus that drives performance lets a body rebuild without heavy loading.
The equipment
The Logic ball
Two 20–22 cm balls (8–8.7 in), non-slip, rated to 200 kg (440 lb), with a carrying bag. The rolling, deformation and spring rebound the method depends on come from the ball itself — small enough that corrections have to be fast, deformable enough that the surface never repeats.
How it works
Strength and muscle without heavy weights?
A heavy set takes you near failure in 5 reps, but only in a few prime movers. On the Logic ball, at the right level, 5 reps is just as hard, and the stabilizers work near failure too: dozens of muscles near their own limit at once, at low load.
Gym-goers and athletes who switched to Logic, or swapped 2 hours of their training for it, all added at least 15% to their PR lifts in one month, in weight or in reps. Olympic athletes included. Established with 1000+ people over 10 years.
Why Logic is different
Measured, not guessed.
Logic was built by a physicist and an engineer, and it runs like a lab: a named mechanism, measured numbers, a result established with 1000+ people over 10 years, and a first study that confirmed it. Next, a university study built for full peer review. No number without its method.
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17×
the reactive demand of weight training
Our measurements, Pilates = 1×: Logic Workout 50×, weight training 3×. Wrist accelerometry (Apple Watch): jerk and Welch power spectral density, 3 axes, 2 to 12 Hz. Reactive demand is our proxy for how many muscle fibers have to work.
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+15%
minimum on PRs, in one month
Gym-goers and athletes who switched to Logic, or swapped 2 hours of their training for it. All of them, in weight or in reps.
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First
study confirmed it
Open-access preprint on arXiv (2506.13959), peer review pending. Next: a university study, built for full peer review.
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2 h
a week. The whole program.
The mechanism
The Reactive Falling Effect
The ball produces three forces at once — rolling, chaotic deformation, and a spring rebound — so your nervous system can never pre-load a motor pattern. The Logic ball is 18 to 22 cm: it rolls, deforms and springs back about ten times a second, close to human reaction time, so corrections have to be fast. A Swiss ball moves you less than once a second, and even a 30 cm ball gives 30 to 40% less reactive demand.
Accelerometry shows roughly ten times the jerk of a stable, maximally braced push-up, and 17 times the reactive demand of weight training. Reactive demand is our proxy for how many muscle fibers have to work, not a count of them. A university study, built for full peer review, will measure the recruitment directly.
Method: Apple Watch wrist accelerometer, 2–12 Hz band. Push-up: jerk and spectral power, against a stable push-up matched for voluntary tension. Weight training: jerk and Welch power spectral density, 3 axes, our measurements. A demand characterisation, not a recruitment measurement.
Read the science
A first study confirmed it. Next, a university study built for full peer review: to take part or support it, contact us. Below, our two open-access preprints on arXiv, peer review pending, and independent press coverage — read them and judge for yourself.
Preprint
Harnessing the Reactive Falling Effect for rehabilitation and performance boosting
A first cohort reported gains in strength and performance on 1 to 3 hours a week, and resolution of chronic pain.
Sornette & Sornette, 2025. Open-access preprint on arXiv (2506.13959), peer review pending.
Preprint
Case study of a 75-year-old woman with Parkinson's disease
A single-case rehabilitation trajectory with Logic Workout training.
Sornette & Sornette, 2025. Open-access preprint on arXiv (2510.23093), peer review pending. A single case, not a controlled trial.
Press
Nature doesn't optimize for comfort — how instability makes you resilient
The method in the Swiss monthly.
Schweizer Monat, independent press coverage.
Athletes using Logic Workout
Training less, they report better results than years of their old programs.
Olympic fencing
Nathalie Moellhausen
Cut her training from 10 hours a week to 3 and reported better performance — faster recovery, more time on fencing skill.
Athlete-reported.
Strength & mass
Soop
His physique fronted the Expendables poster. He added Logic Workout to push his strength and mass further — without ever touching a weight.
Weightlifting
David
Added 25 pounds to his squat after years of plateau, on one hour of Logic a week.
User-reported result.
Common questions
How can Logic Workout outperform weight training for strength?
By taking every muscle near failure, not just a few. A heavy set gets a few prime movers there in 5 reps. On the Logic ball, at the right level, 5 reps is just as hard, and the stabilizers work near failure too. Gym-goers and athletes who switched or swapped 2 hours of their training to Logic all added at least 15% to their PRs in one month.
Isn't this just instability training?
No. Instability training puts a wobble under a lift, and the wobble steals force from the lift. The studies agree it loses to weights, and so do we. Logic Workout is built around the fall itself: catching it is the load. At the right level, 5 reps on the Logic ball is as hard as a heavy set, with every stabilizer near failure too.
Is this Pilates with a ball?
It looks like Pilates. It's almost the opposite. Pilates is slow, controlled and predictable: it builds flexibility and control. Logic is fast, reactive and unpredictable: the 18 to 22 cm ball rolls, deforms and springs back about ten times a second, for 50 times the reactive demand of Pilates in our measurements. You keep the control, and you get the strength.
How much time does the program take?
From ten minutes a day to four hours a week, depending on your goal. The method's creator advocates two hours a week — four sessions of 30 minutes — for an athlete-level body.
Will it replace heavy lifting?
Unless you are a bodybuilder chasing hypertrophy in one specific muscle, or competing in a lift where the exact movement under load is the event — yes. A heavy set takes a few prime movers near failure in 5 reps. On the Logic ball, 5 reps is just as hard, with every stabilizer working too: 17 times the reactive demand of weight training, in our measurements.
Gym-goers and athletes who switched or swapped 2 hours of their training to Logic all added at least 15% to their PRs in one month. Yes, this is strength training. 2h of Logic beats 6h of weights.
Two hours a week
Don't believe the science? Try it yourself.
Note your max today. Swap 2 hours a week for Logic. Check it in a month.
Free for 14 days
The other Logic apps
Same method, applied to sleep and to breath.
