A coach for tempo, cues, and rep quality

Set a tempo, in your own words

A tempo is four durations (eccentric, bottom pause, concentric, top pause), and the concentric can be timed or explosive. Set one per exercise in the editor, or have your coach set it. A coach's tempo wins while it is active, and if they clear it you go back to the one you set.

You can also name the four phases. "Down, hold, up, hold" and "lower, pause, drive, squeeze" are the same prescription in different words, so you pick yours. You rename all four or none, so the cues don't mix your words with the defaults.

Tempo is off by default and set per exercise. The program generator does not set one, so if you leave this alone, nothing changes.

A pacer you can hear and see

Once the set starts, MuscleBuddy talks you through it: a lead-in and countdown, a "go" on the first rep, each phase as it arrives, your rep count as each rep finishes, and a warning at the start of the last rep. Your phone keeps count, so it can stay in your pocket.

When cues fall at the same moment they are spoken in a fixed order: "One. Last rep. Down." The number closes the rep that ended, the warning opens the next one, and the instruction comes last so it is the word you hear.

If the phone is propped where you can see it, the pacer fills the screen: the phase word large enough to read from the floor, a ring counting down the phase, reps done against reps planned, and a wake lock so the screen stays on. The screen and the audio run from the same cue schedule, so they stay in step.

Tones, volume, speech, vibration, rep counting and countdown length each switch on and off separately, and they are saved on each device instead of synced, since they suit one phone in one gym. Muting your phone at one gym does not mute your coach's tempo everywhere. The pacer works with any one channel off.

Rep Trace: what your set measured

Prop your phone and film a set. MuscleBuddy reduces the clip to a single motion signal and reads the rep count and the duration of each phase from it: "eccentrics averaged 1.2s against a prescribed 3.0."

The motion is drawn as a line over time, so you can see the shape of the set instead of reading a table of seconds. There is no target line or shading over it, because it shows a measurement, not a score.

Film without a tempo set and you still get your rep count, with no comparison. If a clip doesn't split into clean reps, MuscleBuddy tells you why instead of giving you a count you shouldn't trust.

Cue Check: coaching cues, only when you ask

Pick the reps you care about and get coaching cues based on that exercise's stored form cues, each with a confidence level and what in the frame supports it. An AI vision model reads the clip, and it runs only when you tap for it, since each pass costs money and most sets don't need one.

Cue Check does not score a rep or give a verdict. If the model's response includes a joint angle, a numeric score or a pass/fail, the whole response is rejected, because a single phone camera cannot measure joint angles reliably. You get the kind of cue a coach would give watching the same clip.

Your clips stay yours

A filmed set is your data. A coach can view a clip only while you work together, and cannot run a Cue Check on it or delete it. Clips expire after 30 days unless you pin one.

How it reads the rest of MuscleBuddy

Rep Coach reads the load and tempo your Training program prescribes, so it compares you against your own plan. A set that came in rushed is context your coach sees beside the rest of your training log.