Using your lap button on structured workouts

When you do intervals, tempo, or threshold runs, pressing your watch's lap button at the start and end of each rep is the single biggest thing you can do to get richer, more accurate coaching feedback from PaceLab.

What the lap button does

Your watch records a continuous stream of pace, heart rate, and distance — but it doesn't know where one rep ends and the next begins unless you tell it. The lap button (sometimes called "split" or "back" depending on the watch) marks the boundary so each rep gets recorded as its own segment.

When to press it

• At the start of every work interval — the first stride of your first 800m rep, your second, your third, etc.
• At the end of every work interval— when you've hit the target distance or time and are about to jog or walk.
• Once at the end of the cooldown — closes the final segment cleanly.

You don't need to press it during easy runs or long runs — just structured workouts where the reps matter.

Where the lap button is on your watch

• Garmin Forerunner / Fenix / Epix— the bottom-right button by default (labeled "Back"/"Lap"). Check Activity Settings → Buttons if you've remapped it.
• Apple Watch — double-tap the screen during the Workout app (or use the lap watchOS gesture if configured). Apple Watch workouts reach PaceLab through Apple Health on the iPhone app.
• COROS APEX / Pace / Vertix — the BACK button by default; some models support a quick-tap during workout mode.

If you're on a different watch, look for "lap", "split", or "interval" in your watch's activity settings. Most modern GPS watches support it — see connecting a device we don't support directly for how the data gets to us.

Why it matters for your coaching

With clean lap data, PaceLab can grade each rep individually — was rep 1 too fast, were reps 4-6 fading, did your heart rate drift? Without lap markers we have to guess from one big blob of data, which means coaching feedback becomes generic instead of actionable.

You'll also see per-rep splits in your activity detail page, and your post-run share text on Strava will reflect the actual structure of what you ran.

Already missed the lap button on a workout?

No big deal. PaceLabstill grades the overall effort from heart rate and pace zones; you just won't get the per-rep view this time. If you regularly forget on structured sessions, your coaching feedback will mention it so you can build the habit. Every workout going forward is a fresh chance.