Apple Watch Running Intervals: Setup, Alerts and Scheduling

In short: there are three ways to run intervals on an Apple Watch. Build a Custom Workout in the Workout app on the watch. Build the same thing in the Fitness app on your iPhone (with watchOS 26 on the watch), which syncs it over. Or let an iPhone app schedule structured workouts onto the watch through Apple’s WorkoutKit, so the session is waiting when you start your run. Pace and heart rate alerts tell you when you drift out of range.

This guide walks through each one with the current watchOS steps, using one session as the example: 6 × 800 m with 2-minute jog recoveries, plus a warm-up and a cool-down.

Three ways to get intervals onto your Apple Watch

Method	Where you build it	What the watch shows	Best for
Custom Workout on the watch	Workout app, on your wrist	Time, distance or open steps, plus alerts	A one-off session you set up at the track
Custom Workout on iPhone	Fitness app on iPhone (watchOS 26 or later)	The same, built on a bigger screen with repeat blocks	Sessions you reuse every week
Scheduled by an app (WorkoutKit)	Nowhere: the app writes it	Whatever the app sends, such as a pace range on every step	Following a training plan without building anything

All three end up in the same place: the Workout app on your watch, with step-by-step screens and a tap on the wrist at every change.

Build a custom interval workout on Apple Watch

Apple’s current steps for watchOS (Apple Support: Create a Custom Workout on Apple Watch):

Open the Workout app on your Apple Watch.
Turn the Digital Crown to Outdoor Run (or Indoor Run for a treadmill).
Tap the Goals button, tap Custom, then tap the Add button.
Tap Warmup, then choose Time, Distance or Open. An open warm-up lets you start the first rep when you’re ready.
Tap Add, tap Work, choose Distance and set 800 m.
Tap Add, tap Recovery, choose Time and set 2 min.
Add work and recovery steps until you have six of each.
Tap Cooldown, then choose Time, Distance or Open.
Tap New Custom Workout below Custom Title and give it a name, such as “6×800”.
Tap Create Workout.

Three details trip people up:

The Create Workout button stays grey until you’ve added at least one work or recovery interval.
Distance isn’t offered for stationary workouts such as Elliptical. Indoor Run is fine, but treadmill distance from the watch is an estimate, so time-based reps are usually cleaner indoors.
Custom Workouts work in every workout type except Multisport and Open Water Swim.

To delete an interval, swipe left on it and tap Delete. To drop the warm-up or cool-down, open the workout’s edit screen, tap Warmup or Cooldown, tap Goal Type, then tap Skip.

A hand adjusts custom interval workout settings on an Apple Watch displayed in a sketch illustration.

Build it on your iPhone instead

Tapping out six reps on a watch screen gets old. With watchOS 26 on a paired watch, the Fitness app on iPhone has the same builder on a larger screen, and workouts you make there sync to the watch automatically (Apple Support: Customize a workout in Fitness on iPhone):

Open the Fitness app on your iPhone and tap Workout.
Scroll to Outdoor Run, tap the options button next to it, tap Custom, then tap Add.
Tap Warmup or Cooldown, tap Goal Type, then pick Time, Distance or Open.
Tap Add Step, choose Work or Recovery, and set the goal type and value.
Tap Add Repeat to repeat the 800 m and the 2-minute recovery six times, instead of adding twelve steps one by one.
Tap Target on an interval to give it a target. You can also name each interval.
Use Reorder to drag steps into place, name the workout and save it.

The repeat block is the main reason to build on iPhone. “6 × (800 m + 2 min)” becomes one block, and going from 6 to 8 reps next month is one change.

Add pace and heart rate alerts

Structure tells you when each rep starts and ends. Alerts tell you whether you’re running it at the right effort.

A target on each rep. In the iPhone builder, the Target on a work interval gives that rep its own target, such as a pace range for the 800s. Recoveries can stay open, or get a heart rate ceiling so you don’t jog them too fast.
Alerts for the whole workout. On the watch, turn the Crown to the workout, tap the Alerts button, choose an alert and configure it. Apple’s example is an Outdoor Run alert for a heart rate of 133–141 bpm. Alerts you add here are used every time you do that workout (Apple Support). Custom workouts support alerts for pace, heart rate, cadence and power (Apple Support: Work out with Apple Watch).
Heart rate zones. Zone alerts use your Heart Rate Zones, which the watch calculates from your health data unless you set them by hand in the Apple Watch app on iPhone (My Watch > Workout > Heart Rate Zones).

A practical setup for 6 × 800 m: a pace range on each 800 m rep, at most a heart rate ceiling on the recoveries, and an open cool-down.

During the run

Up Next view. Turn the Digital Crown to the Up Next workout view to see what’s left of the current interval and what comes next.
Feel the changes. If you miss the tap at the start of a rep, go to Settings > Sounds & Haptics > Haptics on the watch and choose Prominent, which adds an extra tap that announces some alerts (Apple Support: haptic alerts). A snug strap with skin contact helps too.
Mark a segment. Double-tap the display to mark a segment, for example a rep you had to cut short at a crossing. On Apple Watch Ultra, the Action button can mark segments, and Precision Start begins the workout without a countdown (Apple Support: Run with Apple Watch).
Show fewer metrics. For short reps, current pace, interval time and heart rate are enough. Save form metrics like Ground Contact Time for easy runs, when you have attention to spare.

After the run, open the Fitness app on iPhone, tap Sessions, tap the workout and scroll down for your segment stats (Apple Support: Adjust Apple Watch during a workout). The Activity app’s training load view shows how your last 7 days of workouts compare with your usual load.

Scheduled workouts from third-party apps (WorkoutKit)

Building every session yourself is fine if you run one interval day a week. If you follow a plan with two or three structured sessions every week, it turns into admin.

Apple’s WorkoutKit framework lets an iPhone app build a structured workout (warm-up, repeat blocks, recoveries, a goal and an alert on each step) and, with your permission, schedule it on your Apple Watch. Scheduled workouts appear in their own section of the Workout app, with the app’s icon and name, and in the Fitness app on iPhone (Apple Developer: WorkoutKit, Apple Developer: Health and fitness apps). You start them like any other workout, and the recording is saved to Apple Health as usual.

What a scheduled workout gives you depends on the app. Some apps are simply better editors: you still decide every rep, they only save the tapping. Coaching apps decide the session too.

Let a coach schedule the intervals for you

TextFit is an AI running coach for iPhone that uses this WorkoutKit route. You tell the coach your goal, the days you can train and your current fitness in your own words (“10K in 49 minutes”). It plans your week, including where the interval sessions go, and keeps the next 7 days scheduled on your Apple Watch.

What that means for intervals:

The coach picks the session and its day. Intervals and threshold runs are key workouts: at most two hard days a week (three above 8 sessions), never back to back, with about 80% of your running easy.
Paces come from your threshold. Interval reps get a narrow band of your threshold speed (104–110%) and threshold reps 97–102%, so a runner with a 5:00 per km threshold sees interval reps at 4:33–4:48 per km. If the coach doesn’t know your threshold yet, it schedules a test first and sets hard work by heart rate or effort until you report the result.
Each step carries an alert. The watch gets each step’s pace or heart rate range as an alert, so you feel it when a rep drifts. Step names on the watch need iOS 18 and watchOS 11 or later.
Changes reach the watch. Write “working late Tuesday, move my intervals to Wednesday” in the coach chat. The coach moves the session, the change shows up with an Undo button, and the watch schedule follows.
The run comes back. Apple Health returns the workout, and the coach compares it with the plan: duration, distance, pace, and how many reps stayed within ±2% of their pace target, for example “5/6 · 83%”.

The Workout app runs the session, step by step. More on how TextFit works with Apple Watch.

Which method should you use?

One interval session now and then: build it on the watch.
The same few sessions every week: build them in the Fitness app on iPhone with repeat blocks, then reuse them.
A whole plan you don’t want to write yourself: let an app schedule the sessions through WorkoutKit and save your effort for the reps.

Apple Watch intervals: common questions

Can I run intervals on a treadmill with Apple Watch?

Yes. Choose Indoor Run and build the session the same way. Use time-based reps where you can, because the watch estimates indoor distance and it rarely matches the treadmill display exactly.

Why doesn’t my watch buzz at the start of a rep?

Usually it did and you missed it. Set Haptics to Prominent, wear the watch snugly, and keep the screen simple so you react to the cue instead of reading numbers.

Do I need an Apple Watch Ultra for intervals?

No. Custom Workouts, alerts and scheduled workouts work without it. The Ultra adds the Action button for marking segments, and Precision Start.

Can a training app put intervals on my watch automatically?

Yes, if it uses WorkoutKit scheduling. You allow it once, and its workouts appear in the Workout app under the app’s name. TextFit does this for every session in your plan (runs, rides, swims and strength) for the next 7 days.

Where do I see each rep’s pace after the run?

In the Fitness app on iPhone: tap Sessions, tap the workout and scroll down to the interval and segment details.

Want the 800s on your wrist before you head out? TextFit’s AI running coach plans your week, schedules each workout on your Apple Watch with paces in your numbers, and changes the plan when you tell it what changed. Try it free for 14 days on iPhone.