MaximumTrainer

An open-source, high-performance indoor cycling training application built with the Qt framework (C++17). MaximumTrainer delivers structured interval workouts with real-time power, cadence, heart rate, and speed feedback, and controls smart trainers automatically via FTMS ERG mode. Browse and sync workouts from intervals.icu, or import your own .erg / .mrc / .zwo files.

📖 Want to use the app? See the User Guide — pairing sensors, finding & building workouts, training, Studio mode, and more.

Download

Prebuilt binaries for each release live on the Releases page — you don't need to build from source unless you want to. Grab the asset for your platform from the latest release:

Platform	Asset	Notes
Linux	MaximumTrainer-linux-x86_64.AppImage	chmod +x it and run — self-contained, no install
Windows	MaximumTrainer-windows-x64.msi (installer) or -windows-x64.zip (portable)	Windows 10 1703+
macOS	MaximumTrainer-macos.dmg	Open and drag to Applications
Web (WASM)	MaximumTrainer-wasm.zip	Runs in a WebAssembly-capable browser

Prefer to compile it yourself? See Building below.

Technical Overview

Item	Details
Language	C++17 (≈ 95 % C++)
Framework	Qt 6 (6.7+) on all platforms
Build file	MaximumTrainer.pro (qmake)
Qt modules	core · gui · widgets · network · bluetooth · webenginewidgets · printsupport · concurrent
Trainer protocol	Bluetooth LE Fitness Machine Service (FTMS / 0x1826) for ERG resistance control
Sensor profiles	Heart Rate (0x180D) · Cycling Speed & Cadence (0x1816) · Cycling Power (0x1818) · Moxy Muscle Oxygen (0xAAB0)
Workout formats	.erg, .mrc, .zwo (imported and converted to the native XML format) · Intervals.icu calendar sync · export as .fit
Workout source	Integrated intervals.icu for online workout plans

Using MaximumTrainer

For everything about using the app — pairing sensors, finding / importing / creating workouts, ERG vs Slope, the workout player (video · web · Retro Race game), Studio mode, activity uploads, and troubleshooting — see the User Guide.

No hardware? A built-in Simulation mode emits realistic drifting power / HR / cadence / speed and responds to ERG commands, so you can exercise the full workout flow — handy for development and CI — without any Bluetooth devices.

Screenshots

Workout library

Workout editor

Devices — pairing & trainer config

Workout in progress

Studio mode — per-rider configuration

Retro Race — ghost-race game mode

Building

All three platforms are built and tested automatically via GitHub Actions CI (see .github/workflows/build.yml). Use MaximumTrainer.pro with qmake and a standard C++ compiler.

Dependencies

Dependency	Version	Platform	Notes
Qt	6.x (6.7+)	all	Core framework (incl. QtMultimedia, QtWebEngine, QtBluetooth)
QWT	6.3.0	all	Plotting widgets (built from source against Qt 6)

Audio & media playback: both sound-effect feedback (interval beeps, etc., via QSoundEffect) and the embedded video + internet-radio player (QMediaPlayer / QVideoWidget / QAudioOutput) use Qt's own QtMultimedia. There are no SFML or VLC dependencies.

Windows — Requirements

• Windows 10 version 1703 (Creators Update) or later is required. Windows 7, 8, and 8.1 are not supported (missing WinRT BLE APIs).
• A Bluetooth 4.0+ adapter with a WDM-compatible driver.
• No special permissions or manifest entries are needed.

Windows

Required tools: Qt 6.x (msvc2019_64, with the qtwebengine, qtconnectivity, qtmultimedia, qtwebchannel, qtpositioning modules), Visual Studio 2019+ (MSVC).

Environment variables — set before running qmake:

Variable	Description	Example
QTDIR	Qt installation root for the target arch	C:\Qt\6.7.3\msvc2019_64
QWT_INSTALL	QWT installation root (built against Qt 6)	C:/qwt

qmake invocation:

qmake MaximumTrainer.pro `
  "QWT_INSTALL=C:/qwt"

The Windows Kit libraries (Gdi32, User32) are resolved automatically by the MSVC linker.

Download links:

• Qt 6.x: https://www.qt.io/download
• QWT 6.3.0: https://sourceforge.net/projects/qwt/files/qwt/6.3.0/

Linux

Install Qt 6 + dependencies, build QWT 6 from source (no Qt6 qwt apt package exists), then build the app:

sudo apt-get install -y \
  qt6-base-dev qt6-webengine-dev qt6-connectivity-dev \
  qt6-multimedia-dev qt6-webchannel-dev qt6-positioning-dev \
  cmake build-essential

# Build QWT 6.3.0 from source against Qt 6 (installs to /tmp/qwt6 here)
cd /tmp && curl -L -o qwt.tar.bz2 \
  "https://sourceforge.net/projects/qwt/files/qwt/6.3.0/qwt-6.3.0.tar.bz2/download"
tar xf qwt.tar.bz2 && cd qwt-6.3.0
qmake6 qwt.pro && make -j$(nproc)
make install INSTALL_ROOT=/tmp/qwt6-stage
mkdir -p /tmp/qwt6 && mv /tmp/qwt6-stage/usr/local/qwt-6.3.0/* /tmp/qwt6/

# Build MaximumTrainer
cd /path/to/MaximumTrainer_Redux
qmake6 MaximumTrainer.pro QWT_INSTALL=/tmp/qwt6
make -j$(nproc)
# Run (QWT in a non-standard prefix needs LD_LIBRARY_PATH):
LD_LIBRARY_PATH=/tmp/qwt6/lib ./build/release/MaximumTrainer

Wayland: QtWebEngine and some embedded native widgets are more stable under XWayland than the native Wayland QPA plugin, so on a Wayland session the app forces the xcb platform automatically. Set QT_QPA_PLATFORM yourself to override.

macOS

Uses Qt 6.7.3 with Clang. QWT is built from source (non-framework) against Qt 6.

macOS Bluetooth permission: The app's mac/Info.plist includes the NSBluetoothAlwaysUsageDescription key, which is required by macOS 10.15+ for any app that accesses BLE devices. The first time the app attempts to connect a sensor, macOS will prompt for Bluetooth permission. This permission can be reviewed or revoked in System Settings → Privacy & Security → Bluetooth.

# Install Qt 6.7.3 via install-qt-action or the Qt Installer, then:

# Build QWT 6.3.0 from source (non-framework, required for Qt 6)
curl -L -o /tmp/qwt.tar.bz2 "https://sourceforge.net/projects/qwt/files/qwt/6.3.0/qwt-6.3.0.tar.bz2/download"
tar -xjf /tmp/qwt.tar.bz2 -C /tmp && cd /tmp/qwt-6.3.0
sed -i.bak 's/QwtFramework//' qwtconfig.pri
qmake qwt.pro && make -j$(sysctl -n hw.logicalcpu) && sudo make install

# Build MaximumTrainer
cd /path/to/MaximumTrainer_Redux
qmake MaximumTrainer.pro \
  "QWT_INSTALL=/usr/local/qwt-6.3.0"
make

Testing

MaximumTrainer has a multi-tier test suite covering BLE parsing, service APIs, UI flows, and integration scenarios — all run headlessly in CI without real hardware.

Test tiers

Suite	Location	What is tested
BLE unit tests	tests/btle/	BLE characteristic parsing (HR, CSC, Power, FTMS), SimulatorHub signal emission, trainer simulations (Elite, Wahoo KICKR, Garmin Tacx), battery level, interval summary
Service unit tests	tests/strava/, tests/intervals_icu/	HTTP request construction, auth headers, URL patterns, null-manager guards for the Strava and Intervals.icu upload services
ZWO importer tests	tests/intervals_icu/	Parsing of SteadyState, Ramp, IntervalsT, FreeRide, mixed, and malformed ZWO workout files
Credential store tests	tests/credential_store/	Round-trip read/write, overwrite, remove, missing key, multi-service, WASM no-op
Plan adherence tests	tests/plan_adherence/	Completed/skipped/substituted entries, adherence %, encode-decode, change signals
Logger tests	tests/logger/	Log level filtering, output format, file write enable/disable
Studio tests	tests/studio/	Multi-hub simultaneous signals, user-ID propagation, FTP scaling
Login screen tests	tests/integration/	OAuth dialog state, offline login path, Intervals.icu OAuth URL generation
Workout UI tests	tests/integration/	Full ERG session driven by SimulatorHub through WorkoutDialog; interval advancement; data accumulation
Offline / BLE integration	tests/integration/	BLE adapter smoke test, offline mode screenshot, runtime validation
Playwright (E2E)	tests/playwright/	WASM asset loading, Web Bluetooth API mock, login screen, landing page

Running the BLE unit tests

cd tests/btle
qmake btle_tests.pro
make -j$(nproc)
../../build/tests/btle_tests -v2

The BLE suite has 51 test cases across HR parsing, CSC, Power, FTMS, trainer simulations, SimulatorHub, battery, and interval summary. See the CI run status for pass/fail counts on Linux, Windows, and macOS.

Log Files

MaximumTrainer writes diagnostic messages (network errors, BLE events, OAuth login steps) to a log file. File logging is enabled by default on first launch; you can adjust the level or disable it in Preferences → Logging.

Platform	Default log file path
Windows	%APPDATA%\MaximumTrainer\MaximumTrainer.log (e.g. C:\Users\YourName\AppData\Roaming\MaximumTrainer\MaximumTrainer.log)
macOS	~/Library/Application Support/MaximumTrainer/MaximumTrainer.log
Linux	~/.local/share/MaximumTrainer/MaximumTrainer.log (XDG data dir; override with $XDG_DATA_HOME)

Set the log level to Debug before reproducing an issue, then attach the log file to your bug report. The Open log file button in the Logging settings page opens the file directly in your default text editor.

For full troubleshooting guidance see the User Guide — Log Files & Troubleshooting section.

TODO

Project now going through new revisions, with plans to enhance as an open-source interval trainer for indoor cycling & indoor rowing. backlog and work items can be found here