# MuscleBuildingRecorderApp > MuscleBuildingRecorderApp (iPhone/iPad app by Kiichi Yokokawa.) - Source: https://appshunter.io/ios/app/musclebuildingrecorderapp/id6754168901 (this page in markdown: same URL + `.md`) - Developer: [Kiichi Yokokawa](https://appshunter.io/developer/1821969475) - Category: Health & Fitness, Productivity - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 17.0 · 13 MB - Languages: American English, Japanese - Released: 2026-01-12 - Data updated: 2026-08-10 - User reviews in markdown: https://appshunter.io/ios/app/musclebuildingrecorderapp/id6754168901/reviews.md ## What is MuscleBuildingRecorderApp? 【Strength Training Log - Heart Rate Workout Tracker】 Track your sets, rest periods, heart rate, and workout history in one place. MuscleBuildingRecorder works with iPhone and Apple Watch to help you manage exercise time, rest time, exercise details, load, reps, notes, and heart rate during training. MuscleBuildingRecorder is designed for people who want more than a simple stopwatch. It helps you turn each workout into a clear training record, with separate tracking for work and rest phases, heart rate data, notes, tags, presets, and session history. Main Features Real-Time Heart Rate Monitoring • Supports Apple Watch, Bluetooth heart rate monitors, and compatible AirPods Pro heart rate sensors • Displays heart rate in real time during workouts • Records average, maximum, and minimum heart rate • Helps you review workout intensity and recovery trends Strength Training Timer • Separately tracks workout time and rest time • Manages sets and workout cycles • Shows total workout time, work time, and rest time • Supports rest notification settings • Supports session restoration if a workout is interrupted Detailed Workout Logging • Record exercise name, category, load, and reps • Save notes for each set • Add tags and fatigue details for better review • Manage exercises by category, such as chest, back, and legs • Use presets to start frequently used routines faster History and Export • View summaries for each session • Check heart rate graphs to review workout intensity • Browse past workout history • Review and export records across multiple days • Export data in CSV and JSON formats Apple Watch Integration • Control workouts from Apple Watch • Sync timer and phase changes between iPhone and Apple Watch • Track heart rate while continuing your session • Continue workout recording in the background • Supports exercise input and workout actions from Apple Watch Live Activities • Check your workout status from the Lock Screen or Dynamic Island • View the current work/rest phase • Quickly see elapsed time and heart rate Customization • Adjust button layout • Configure rest notifications • Manage tag presets • Create and edit workout presets Recommended For • People who want to record each strength training set accurately • Lifters who manage load, reps, and rest time • Apple Watch users who want heart rate data during workouts • Anyone who wants to review workout history and improve over time • Users who want to export workout data in CSV or JSON format • Anyone looking for more than a basic workout timer Pro Benefits • Ad-free workout experience • View results immediately after completing a workout • Access to selected customization features Pro is available as a monthly subscription or a one-time purchase. Data Privacy • Workout records are primarily stored locally on your device • HealthKit access requires your permission • Recorded data can be exported in CSV or JSON format when needed • Cloud sync is not currently provided Requirements • iOS 17.0 or later • watchOS 10.0 or later when using Apple Watch • HealthKit permission for heart rate tracking • Bluetooth permission when using a Bluetooth heart rate monitor Simple Workflow 1. Select an exercise 2. Enter load and reps 3. Start the set 4. Track time and heart rate 5. Manage rest time 6. Move to the next set or finish the session 7. Review your summary and history Record your strength training more accurately and make every workout easier to review. With MuscleBuildingRecorder, your training becomes useful data you can build on. 【Support】 For questions or requests, please contact us from the app settings. 【Terms of Use】 https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ 【Privacy Policy】 https://yok1012.github.io/MuscleBuildingRecorder/ ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | 月額サブスクリプション | $0.99 | per month | **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | MuscleBuilding Pro(買い切り) | $4.99 | one-time | ## Version history (last 5 releases) ### 1.5 — 2026-07-12 ■ Unified Exporting • Organized into three types: "Complete Data (JSON)," "Complete Data (CSV/ZIP)," and "Summary (CSV)." • Complete Data includes all exercises, sets, heart rate, sensors, and notes, manageable in a single file. ■ Heart Rate Acquisition Improvements • Supported heart rate monitoring for AirPods Pro 3 / Powerbeats Pro 2 (Automatic acquisition during workouts on iOS 26 or later). • Improved Bluetooth heart rate monitor searching. Connected devices are now displayed in the list. ■ Rest Period Improvements • Redesigned the "Next Menu Input" screen. The input form is now placed at the top, with a rest timer and memo field added. • 30-second/60-second rest notifications now sound even while the app is open. ■ AI Analysis Enhancements *Requires personal API key • Individual workouts in your history can now be analyzed by AI ("AI Analysis for this session" in history details). • AI now utilizes RPE (perceived exertion), tags, next-step plans, and notes recorded during rest periods for analysis. • Heart rate recovery during rest (how much the heart rate dropped) is now reflected in the analysis, enabling advice on recovery capacity and fatigue levels. • Added a "Previous Versions" feature to AI Knowledge. You can restore it to a previous state at any time. • Training knowledge can now be imported into AI Knowledge from external MCP servers (register via AI settings). The AI analysis in this app is an optional feature. Please review the following points: 1. AI analysis uses API keys (Anthropic/OpenAI/Google) obtained by the user. Even if a key is not set, all core functions such as recording, timers, and heart rate measurement will remain fully operational. 2. Only statistical summaries of workout records are sent, and explicit user consent is obtained before the first execution. Data does not pass through the developer’s server. 3. This is not a free-form conversational chatbot; it only generates structured analysis reports based on the user’s own records. 4. The MCP import function manually retrieves information from external servers registered by the user, with a preview confirmation of the content before import. Authentication credentials are stored exclusively in the device’s Keychain. ### 1.4 — 2026-07-03 What's New in Version 1.4 • One-Tap Feedback: During rest, tap presets like "Felt easy" or "At my limit" to log RPE, tags, and your next-set plan all at once. • Heart Rate Recovery (HRR) Score: The post-session summary now visualizes your recovery from each cycle's peak heart rate to the end of your rest. • Bodyweight (BW) Button: Log equipment-free exercises like pull-ups and dips with a single tap. • Smarter Cardio Input: Realistic upper limits for values like speed (km/h) help prevent input mistakes. • Added a free first month on the monthly plan. • Minor stability improvements and bug fixes. Thanks for training with us — we'd love to hear your feedback! ### 1.3 — 2026-06-16 This version improves the workout logging experience, Apple Watch syncing, history review, and data export. The rest screen has been redesigned to make set-by-set logging easier. During rest periods, you can review the previous set and enter details such as load, reps, notes, tags, and fatigue level before moving to the next set. This makes it easier to keep recording without interrupting your training flow. History features have also been improved. In addition to browsing past sessions, you can now review monthly activity with calendar and graph views. This makes it easier to understand your training consistency and see how your recorded activity changes over time. For strength training, this version adds exercise trend views. You can review changes in maximum load, total volume, and maximum reps for each exercise based on your past records. This helps you compare your latest performance with previous sessions and plan your next workout more easily. Data export has been expanded. CSV and JSON exports can now include RPE, tags, notes, next actions, and other set details. Phase-based numeric time-series data is also exported in a more structured format, making heart rate and sensor data easier to review or analyze outside the app. Apple Watch and iPhone syncing has been further improved. Workout start, pause, resume, finish, and work/rest phase changes are now handled more reliably between devices. Actions from Apple Watch and iPhone are reflected more consistently in the active session state. Heart rate tracking has been refined for multiple supported sources, including Apple Watch, Bluetooth heart rate monitors, and compatible AirPods Pro heart rate sensors. During a session, you can view heart rate in real time and review average, maximum, and minimum heart rate after training. Heart rate graphs help you understand workout intensity and recovery trends. Sensor logging has also been updated. A new setting allows accelerometer recording to be turned on or off. This lets you record sensor data only when needed and adjust the amount of data collected based on your training or analysis purpose. Live Activities and Dynamic Island display have been improved. During an active session, you can check the current phase, elapsed time, and heart rate from the Lock Screen or Dynamic Island, making it easier to stay aware of your workout status without opening the app. Customization options have also been adjusted, including presets, tags, rest notifications, and button layout settings. Frequently used exercises and settings are easier to access, and the app can be better adapted to your training style. Pro users continue to get an ad-free experience, selected customization features, and smoother access to results after completing a workout. Screen Time related settings have also been added and refined to support focus during training. You can configure apps to limit during sessions and set apps that should remain available, helping you create a training environment with fewer distractions. This update also includes improvements to ad behavior, rewarded ads, English localization, screen layout, memory handling, and long-session stability. Overall, this version focuses on making MuscleBuildingRecorder more useful as a complete training log, not just a timer. Workout details, rest periods, heart rate, fatigue level, tags, history, and export data are now easier to record, review, and use for planning future sessions. ### 1.2 — 2026-06-07 This version improves the workout tracking experience across iPhone and Apple Watch. - Improved Apple Watch and iPhone workout synchronization - More reliable timer control between devices - Better handling for workout start, pause, resume, and phase changes - Added support for exporting sensor and workout session data - Improved CSV and JSON export behavior - Enhanced heart rate tracking flow with supported heart rate sources - Improved session restoration after an interrupted workout - Better Live Activity updates for active sessions - Added and refined workout history, summaries, presets, tags, and rest-related settings - Improved memory handling during long sessions - General stability, UI, and performance improvements This update focuses on making workout sessions easier to control, easier to review, and more reliable during real training. ### 1.1 — 2026-03-01 v1.1 の新機能: • Proモード追加 - 広告なしで快適に使用可能 • 時間表示の改善 - 筋トレ・休憩・総時間を色分けで見やすく • 重量/回数の直接入力に対応 • Apple Watchとの同期安定性を向上 ## Apps similar to MuscleBuildingRecorderApp | App | Rating | Price | Category | | --- | --- | --- | --- | | [Supplement & Vitamin Tracker](https://appshunter.io/ios/app/supplement-and-vitamin-tracker/id6759703178) | — | Free | Health & Fitness | | [Polar Club - Group fitness app](https://appshunter.io/ios/app/polar-club-group-fitness-app/id840071561) | 4.7 (142) | Free | Health & Fitness | | [Zx: Heart Rate Zones Training](https://appshunter.io/ios/app/zx-heart-rate-zones-training/id1457355997) | 4.3 (70) | Free | Health & Fitness | | [GymGoal Pro](https://appshunter.io/ios/app/gymgoal-pro/id571824492) | 4.8 (1,138) | $8.99 | Health & Fitness | | [筋録組 - ボリューム管理で筋肥大。広告なし筋トレ記録アプリ](https://appshunter.io/ios/app/id6746470494) | — | Free | Health & Fitness | | [Pill Daily: Medication Tracker](https://appshunter.io/ios/app/pill-daily-medication-tracker/id6760611819) | 4.3 (6) | Free | Health & Fitness | ## More apps by Kiichi Yokokawa - [PomodoroTimerApp](https://appshunter.io/ios/app/pomodorotimerapp/id6747931104) - [quickMemoApp](https://appshunter.io/ios/app/quickmemoapp/id6752820914) - [SSHターミナルアプリ](https://appshunter.io/ios/app/ssh/id6777417450) All apps by Kiichi Yokokawa: https://appshunter.io/developer/1821969475 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-10.*