HealthKit's 21 Exercise Constants

Apple's Exercise and fitness group is 21 identifiers, and not one of them measures anything. All 21 belong to the workoutActivity family, which makes them constants you attach to a workout rather than sample types that produce values. The aggregation, unit family and value columns are empty for the whole group, and empty is the correct answer there rather than a hole in the data. The group comes from this site's HealthKit identifier dataset, parsed from Apple's developer documentation on 2026-08-28.

The constant-versus-measurement distinction catches people on first contact with the framework. A quantity type produces samples, each with a number, a unit, a start time and an end time. A workout activity constant produces nothing. It is one label, chosen when a session starts, saying what kind of session this was. Picking highIntensityIntervalTraining does not make HealthKit record intervals, and picking traditionalStrengthTraining does not make it record sets or reps. Everything numeric about the session arrives from elsewhere, which is why products that need per-rep detail run their own workout detection beside the store.

Nine of the 21 date to iOS 8.0: cycling, elliptical, running, walking, stairClimbing, crossTraining, functionalStrengthTraining, traditionalStrengthTraining and preparationAndRecovery. Eight more arrived in 10.0, among them coreTraining, highIntensityIntervalTraining, flexibility, jumpRope, stepTraining and stairs. iOS 11.0 added handCycling and mixedCardio, 13.0 added fitnessGaming for fitness-based video games, and 14.0 added cooldown. So the group grew in two bursts and has barely moved since.

The pair that causes the most grief is traditionalStrengthTraining and functionalStrengthTraining, both from iOS 8.0. Apple separates them by equipment. Traditional is strength training exercises primarily using machines or free weights; functional is strength training primarily with free weights and body weight. Free weights sit in both definitions. Let users choose freely and the same barbell session lands under both labels across your user base, which quietly breaks every filter and chart you build on top.

Two more pairs are worth settling before you build a picker. stairClimbing is for a stair climbing machine, while stairs is for running, walking or drills on real stairs, and Apple's abstract names a stadium or a multilevel building as examples. preparationAndRecovery from iOS 8.0 covers warm-up and therapeutic work such as foam rolling and stretching, while cooldown from 14.0 covers low intensity stretching and mobility exercises following a more vigorous workout. Both are stretching. What separates them is which side of the session they sit on.

Wheelchair users have wheelchairWalkPace and wheelchairRunPace from iOS 10.0, labelling a wheelchair workout at each pace, plus handCycling from 11.0. If your workout type picker omits all three, those users have no way to record what they actually did.

No identifier in this group has a verified Android counterpart in our cross-platform matrix, so treat the whole group as Apple-only until verified and expect the Android mapping to be hand-written. For the plumbing around the constant, the HealthKit integration guide covers permissions and reads, and watchOS workout app anatomy covers where in a session the constant is actually chosen. If the gym is your product, the strength training app guide covers what has to sit beside HealthKit to make a set and rep log work at all.