User Guide

Tempo

Tempo controls the speed of each phase of a repetition, so you can prescribe and cue a specific cadence for resistance exercise. Each rep is timed as concentric : isometric : eccentric : rest, repeated for your chosen reps and sets with a recovery interval between sets, and the total session time is calculated before you start.

Common use-models

• Eccentric loading. Use a long lowering phase for tendinopathy and muscle-tendon rehabilitation, such as a 1:0:3 or 1:0:4 tempo, or Swap to reverse the phases for eccentric-first work.
• Slow, controlled resistance. Slow tempo (for example 3:0:3) to emphasize motor control and increase time under tension at lower loads, such as early postoperative strengthening.
• Isometric holds. Set the concentric and eccentric phases short and the isometric phase long for sustained-contraction work, such as quadriceps or rotator cuff isometrics.
• Motor control and movement quality. A paced tempo makes compensation easier to see, for example trunk lean during a step-down or loss of scapular control at the end of a set.

• Quick presets set common tempos in one tap (for example 1:1:3:0 and 2:2:2:2).
• Show Sets displays the set counter; it turns on automatically when you use more than one set.
• Choose a visualization in Settings: a horizontal track, or a scrolling path showing the whole exercise at a glance.

Tabata

Tabata structures high-intensity interval training as work and rest intervals repeated over a number of rounds, with optional multiple sets and recovery between sets. It opens at 30 seconds work, 30 seconds rest, and 10 rounds (a 1:1 work-to-rest ratio); use 20 seconds work, 10 seconds rest, and 8 rounds (2:1) for the original Tabata protocol. A progress circle shows the current phase and time remaining, and voice announcements call out the phase changes if enabled.

Common use-models

• Return-to-sport conditioning. Build anaerobic and aerobic capacity late in rehabilitation, using low-impact modalities such as bike, sled, or rower for patients who are not yet cleared for running.
• Graded exposure to intensity. Progress the work-to-rest ratio and the number of rounds across visits to dose conditioning load.
• Cardiometabolic and general fitness programs. Time-efficient intervals for patients who can tolerate higher intensities.

Metronome

Metronome provides an auditory (and haptic) rhythmic cue from 1 to 200 beats per minute for cadence-based work. Choose one of three durations: Infinite (runs until you stop it), a fixed time, or a fixed number of beats; the timed and beat-count modes support multiple sets with recovery. Infinite mode can’t be added to a Playlist because it has no fixed end.

Common use-models

• Gait and running retraining. Set a target cadence in steps per minute (measure the baseline with the Cadence tool first) and cue the patient to match it.
• Paced functional tasks. Sit-to-stand, step-up, squat, or heel-raise repetitions at a set rate.
• Rhythmic and dual-task drills. Balance and agility drills, and neurological rehabilitation work that benefits from an external rhythmic cue.
• Breathing and pacing. Slow beats to pace breathing or relaxation during an exercise.

EMOM

“Every minute on the minute.” Set the interval length, the reps per interval, and the number of sets; a new interval begins on schedule and the app tracks sets and reps. The time left in each interval is the rest, so the work-to-rest ratio is set by how quickly the patient completes the reps. Turn on As Long As Possible to repeat the interval until you stop.

Common use-models

• Density-based strengthening. A fixed number of reps each minute, with rest set by the patient’s speed, to build work capacity.
• Progressing volume. Increase the reps per interval or the number of sets across visits while keeping the schedule constant.
• Endurance of postural and stabilizing muscles. Repeated submaximal efforts on a fixed schedule.

Timer

Timer has two modes. For Time counts up to time a task or test, and can be used as a Playlist step. Recovery counts down a rest period and resets automatically when it reaches zero, ready for the next effort.

Common use-models

• Timed functional tests. The Timed Up and Go, five-times sit-to-stand, and similar tests where you record the time to complete a task.
• Timed holds. Single-leg stance, plank, or wall-sit endurance holds, to record time to fatigue or to compare sides.
• Rest intervals. Standardize the rest between sets or between efforts, for example 60–90 seconds for endurance work or 2–3 minutes for heavy strength work.

Playlist

Playlist chains any of the timers above into a single program that runs from start to finish. Use it to build an in-clinic treatment sequence or a home exercise program (HEP) and run it the same way each time. Steps run in order, and the patient is cued through each phase and each transition without handling the device.

• Steps. Each step is a configured timer with its own exercise name and parameters. Reorder steps, edit them, or duplicate them.
• Circuits. Group adjacent steps into a circuit that repeats for a number of rounds, with its own rest between rounds, to program supersets and circuit-style sessions.
• Video and photo demonstrations. Attach a demonstration to any step by recording with the camera or importing from your photo library or Files. Recordings are up to 2 minutes. A step holds either a video or a photo. Media are stored in encrypted form on your device. Patients can review the correct technique at the point of exercise.
• Running a Playlist. Rewind and skip controls pause the timer and wait for you to resume, so you’re never surprised by a jump. A Lock Screen and Dynamic Island display shows the current step and time remaining.
• Sharing. Send a Playlist — steps, timing, and any video or photo — to a colleague or patient by AirDrop or the Share button, or show a QR code to scan (QR codes carry steps and timing only, not videos or photos). The recipient needs RehabKit or Fit-Kit. RehabKit and Fit-Kit can open each other’s shared playlists.
• iCloud sync. Optional. Turn it on in Settings → Playlist Sync to keep playlists on all your devices signed in to the same Apple Account, and choose whether videos and photos sync too. Turning sync off never deletes your playlists.

Common use-models

• Home exercise program. Build the patient’s exercises with demonstration videos and share the Playlist so they can run it between visits.
• Standardized protocols. Save post-operative, return-to-run, or prehab progressions and reuse them across patients.
• Group classes and team warm-ups. Time circuits and stations in a fixed sequence.

Inclinometer

A digital inclinometer for joint range of motion. Place the iPhone on the segment, tap the gauge or Start to zero in the starting position, move the joint to end range (actively or passively), and tap to capture the angular displacement. Readings update continuously while you measure, and each captured value is added to the trial history (newest first).

Common use-models

• Use Redo to discard the latest trial and Clear to start a new set. History persists between sessions until you clear it.
• For side-to-side comparison, send the involved and uninvolved values to the Limb Symmetry Index calculator.

Rotation

Measures rotation about a vertical axis (the transverse plane), where an inclinometer relying on gravity is least useful. Tap to zero, rotate the segment, and tap to capture the angle in either direction, so you can measure internal and external rotation, or left and right rotation, in the same trial list.

Common use-models

• Cervical rotation. Supine with the device level on the forehead, or seated using compatible AirPods Pro or Max as the sensor so no device needs to be held in place.
• Shoulder and hip rotation. Internal and external rotation PROM/AROM in positions where the device can be kept level on the forearm or shank.
• Thoracic and trunk rotation. Seated or standing rotation screens, comparing left and right.

Keep the device level during the measurement. A level indicator is live before you start, and a haptic and on-screen “Keep iPhone flat” warning appear if it tilts too far during a trial, because tilt introduces error into a transverse-plane reading.

Cadence & Stride Coach

Cadence is a tap-along cadence counter. Tap the circle in time with the patient’s steps for a few strides and RehabKit shows steps per minute, discarding accidental taps and using only the most recent 30 seconds. A statistics sheet shows the number of taps, the valid intervals, and the fastest and slowest step intervals, which gives a quick read on rhythm variability.

• Gait training. Establish a baseline cadence during walking or running, then set a target in the Metronome to cue a higher or lower rate.
• Running retraining. Check cadence before and after a cueing intervention without wearables.

Stride Coach (a Beta feature; turn it on in Settings → Beta Features) gives real-time feedback on cadence and foot-strike loudness, using the microphone and motion sensors. It is intended for running gait retraining, where a quieter foot strike is used as an accessible cue for reducing impact. Adjust the cadence window and the frequency band to suit the surface and environment, and calibrate at the start of a run. It is a coaching aid, not a laboratory measure of ground reaction force.

Motion Analysis

Motion Analysis is a 2D video kinematic analysis tool. Record slow-motion video in the app (up to 240 frames per second, with resolution presets from 480p to 4K) or import a clip from Photos or Files, and the app tracks 14 body landmarks in every frame: the neck, both shoulders, elbows, and wrists, and the hip center, both hips, knees, and ankles.

Common use-models

• Running gait analysis. Record a treadmill or overground run from the side or behind, then step through foot strike, midstance, and toe-off frame by frame. Cadence in steps per minute is estimated automatically from the clip.
• Functional movement screens. Single-leg squat, step-down, and landing tasks, reviewing trunk position, pelvic drop, and knee alignment against a before-and-after video.
• Gait observation. Review walking at 0.25× speed and mark joint angles at initial contact or midstance.
• Return-to-sport testing. Capture jumping and cutting tasks, and compare the involved and uninvolved side.
• Documentation and patient education. Show the patient their own movement with the skeleton overlay and angles, and save the session to review at the next visit.

Measuring

• Preset joint angles for the hip, knee, ankle, shoulder, and elbow are drawn as arcs with degree readouts and update as you step through the video.
• Custom measurements. Draw a line or a three-point angle on any frame, for example a trunk lean or a tibial angle, and each frame keeps its own annotations and undo history.
• Correct the tracking. Drag any landmark to its true anatomical position; corrected points are shown in a different color and the angles recalculate.
• Review tools. Frame-by-frame stepping, a scrub wheel, variable playback from 0.25× to 4×, looping, and zoom up to 8× with pan and rotate.
• Joint visibility. Show all landmarks, upper body, lower body, one side, or a custom set, to reduce visual clutter.
• Hands-free capture. Thumbs-up, thumbs-down, and wave gestures can start and stop recording so you can work from the patient’s side.
• Sessions. Analysis sessions are saved on your device with videos stored in encrypted form, and you can export an analyzed video.

Filming for valid 2D measurement

• Place the camera perpendicular to the plane of interest (lateral for sagittal-plane angles, anterior or posterior for frontal-plane angles), at the level of the segment of interest, on a tripod, with the full body in frame.
• Use contrasting, fitted clothing and even lighting. Loose clothing and occlusion by the other limb reduce tracking accuracy.
• Motion out of the camera plane (rotation toward or away from the lens) distorts 2D angles. Treat values as relative and consistent between sessions rather than absolute joint angles.

Automated landmark tracking is an estimate. Verify landmark positions before relying on an angle. Motion Analysis can be turned off in Settings.