TUT - Time Under Tension

Take control of your strength training with a smarter, cleaner approach to the gym.

TUT (Time Under Tension) is built for lifters and athletes who want to focus on what actually stimulates muscle growth: quality movement, mechanical work, and time under tension—without annoying subscription paywalls, clunky menus, or invasive data tracking.

Whether you train in a commercial fitness club, a CrossFit box, or your own garage gym, TUT gives you total freedom to log your workouts your way.

======================== WHY TIME UNDER TENSION? ======================== Rep counts only tell part of the story. TUT helps you monitor the actual mechanical workload and duration your muscles experience during every set. Maximize hypertrophy, track progressive overload with precision, and make every second at the gym deliver results.

======================== KEY FEATURES ========================

• FULLY CUSTOMIZABLE GYM EQUIPMENT No two gyms are identical. Build your personalized equipment catalog from scratch. Add custom machine names, attach your own photos right from your library, set precise resistance increments, and define range-of-motion travel distances. TUT will remember your sets, reps, weight and TUT goals for each exercise.

• INTERACTIVE VITRUVIAN MUSCLE MAPPING Visualize your target muscle groups instantly. TUT’s integrated anatomical map dynamically highlights primary and secondary muscle groups for each piece of equipment, giving you immediate visual clarity on your workout balance. With user feedback this muscle list will grow over time.

• Readiness heatmap model that will show muscles as red when they are fatigued and green when they are ready to lift. Red colors will turn to green slowly as the muscles recover.

• SEAMLESS APPLE WATCH COMPANION Start, track, and monitor sets directly from your wrist. Apple Watch will stream its sensor data to the iPhone TUT app and will be integrated into each workout.

• WORKOUT HISTORY SAVED IN TUT At the end of the day see how many weight lifting sessions you completed. If you are repeating the same exercise with the same parameters the built in coach will prompt you to change things up.

• APPLE HEALTHKIT INTEGRATION TUT connects seamlessly with Apple Health to read your active heart rate and energy burn during workouts, automatically writing your completed strength training sessions and total caloric burn back to your Health app.

• 100% PRIVATE BY DESIGN Your health and fitness data belongs strictly to you: - No account registration, email, or passwords required. - No third-party analytics, tracking SDKs, or data brokers. - No external private servers. All your data and custom photos stay right where they belong: on your physical devices and securely backed up to your personal, Apple-encrypted iCloud.

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