Hangboard Trainer

Evidence-based finger strength training app for climbers. Built with React Native / Expo.

Guided workouts with real-time voice coaching. Runs on iOS and Android.

Training Protocols

Protocols are sourced from peer-reviewed sport science research:

7/3 Repeaters (Intermediate)

7-second hang / 3-second rest × 6 reps per set, 3 sets per grip, 2-minute set rest.

• Goal: Strength-endurance and grip stamina
• Research: López-Rivera & González-Badillo (2019) — 45% endurance improvement over 8 weeks; Anderson Brothers (2015) — +21.5% strength after 4 weeks

Max Hangs (Advanced)

10-second maximum-effort hangs, 5-minute rest between hangs.

• Goal: Maximum finger strength via neural adaptation and structural loading
• Research: Eva López PhD research — up to 28% strength improvement per 8-week cycle; F100 intensity group +14.3% strength (Frontiers in Sports, 2022)

Minimum Edge Training (Advanced)

10-second hangs on the smallest holdable edge, 5-minute rest between sets.

• Goal: Direct climbing specificity, finger strength with progressive edge reduction
• Research: Eva López MED protocol — target 75–103% MVC-7; reduce edge by 1–2mm when margin exceeds 5 seconds

Density Hangs (Beginner)

20-second hangs at 75% intensity, 3-set rest between grip positions.

• Goal: Tendon health, collagen remodeling, injury prevention
• Research: Dr. Tyler Nelson Density Hangs protocol — safest loading approach for tissue adaptation

Installation

Option A — Install as a native APK/IPA via EAS Build

Use this to install the app as a standalone native app.

Prerequisites: EAS CLI and an Expo account.

npm install -g eas-cli
eas login
eas build --platform android   # produces a downloadable .apk / .aab
# or
eas build --platform ios       # requires Apple Developer account ($99/yr)

For a quick local APK (Android only, requires Android Studio + SDK):

npx expo run:android --variant release

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Option B — iOS Simulator / Android Emulator (local dev)

Prerequisites:

• iOS Simulator: macOS + Xcode 15+
• Android Emulator: Android Studio with an AVD configured

npm run ios       # opens iOS Simulator (macOS only)
npm run android   # opens Android Emulator

Features

• Real-time countdown timer with phase transitions (warm-up, hang, rest, set rest, complete)
• Voice cues at each phase transition via expo-speech
• Max Hang Time tracker — stopwatch per grip position, personal-best tracking, proportional progress chart for last 10 attempts
• English / Japanese UI and voice coaching (toggle in-app)
• Vibration alerts at hang start
• Screen kept awake during active workout
• Session history stored locally (AsyncStorage)
• Dark theme for gym environments
• Timer reconciles after app backgrounding via AppState + timestamp correction

Architecture

app/(tabs)/index.tsx      — Protocol selection
app/(tabs)/train.tsx      — Active training screen
app/(tabs)/max-hang.tsx   — Max hang time measurement + personal best tracker
app/(tabs)/history.tsx    — Session history

src/data/workouts.ts            — Evidence-based protocol definitions
src/i18n/strings.ts             — EN / JA string catalog
src/services/voiceService.ts    — expo-speech TTS wrapper
src/store/workoutStore.ts       — Zustand session state
src/store/maxHangStore.ts       — Zustand max-hang records (persisted)
src/store/settingsStore.ts      — Language preference (persisted)
src/components/WorkoutTimer.tsx — Countdown timer component
src/components/WorkoutCard.tsx  — Protocol selection card

Research Sources

• López-Rivera & González-Badillo (2019). Journal of Human Kinetics. 8-week RCT on MaxHangs, IntHangs, combined protocols.
• Frontiers in Sports and Active Living (2022, PMC9092147). 7:3 repeaters supplemental training, 10 weeks.
• Frontiers in Sports and Active Living (2022, fspor.2022.862782). F100/F80/F60 intensity comparison.
• Gilmore et al. (2024, PMC11576708). 526 climbers retrospective — Max Hangs + Abrahangs combined.
• Nelson, T. — Density Hangs protocol for tendon conditioning.