ISD Team
28 Apr 2024

Weav Music, a music tech startup, released the running music app Weav Run. This app seamlessly adapts a song’s tempo from 100-240 BPM to match a runner’s steps in real time – without losing the integrity of the song. Running in sync with music helps athletes of all levels run faster and farther, and it can also help prevent injury by improving form.


Numerous applications exist to change the tempo of music. However, when played at alternate tempos, the original arrangement may not convey the original musical intent. This is because the artist carefully crafts the musical arrangement, beat, instrumentation, etc. at the original tempo of their song. Those elements can have a very different character at different tempos.

However, high-quality remixes exist. To create these tracks, a remix artist recomposed musical elements from the original song into a new arrangement with a different tempo, vibe, beat, etc.
We set out to answer: 1) How can we automatically and in real time generate high-quality remixes at tempos triggered by individual listeners? 2) How can music instantaneously adapt to movement?

First, we developed adaptive music capabilities into a proprietary production environment called Weav Mixer. Adaptive music production relies on the seamless recombination of musical elements such as stems into compelling arrangements across different tempo ranges. The Mixer enables artists/producers to structure and orchestrate dynamic interactions among musically related stems. We also developed the Weav Player, which can be embedded in third party apps. It allows users to choose between two playback modes according to their needs.

To create adaptive tracks, we license stems from major labels and use the Mixer to compose dynamically shifting arrangements of the stems. These arrangements maintain a strong beat and musical coherence at tempos not present in the original recording.

Second, we developed the iOS application Weav Run to demonstrate the benefits of adaptive music for runners. Anticipation of each beat is bound with momentum toward each footfall creating a musically driven feedback loop. The stimulus of running with music distracts athletes from feeling physical pain or fatigue by delaying and blocking fatigue-related messages. This can reduce perceived effort and boost mood and endurance.

Weav Run accurately detects cadence (steps/min) using the phone’s internal accelerometer and instantaneously adjusts the adaptive track’s BPM to match cadence from 100-240 BPM; therefore, runners experience music in-sync with their steps. Runners can also use the app to optimize their cadence by setting a fixed BPM and matching their steps to the beat. Optimizing cadence is a key component to efficient, injury- free running because over and under striding leads to bad running form which can lead to injury.

The benefits of adaptive music expand beyond physical activity. It also enhances the musical experience. Listeners experience music responding to their movements, which is a fundamentally different way of interacting with music. We normally think of music as something to which we respond. This new experience surprises and delights listeners.

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