legends · 5 min read ·
Heatmap
A runner's fitness app records a companion at the centre of a reservoir, and then records the runner as the companion.
**RunTrack — Monthly Activity Report**
**Athlete:** Joel Park · **Month:** October · **Sessions:** 22 · **Total distance:** 118 km
*Your heatmap shows your most-used routes. Bright areas are where you spend the most time.*
· · ·
I run every morning before work, five kilometres around the reservoir. For two years the app has drawn my route as a bright ring around the water, with a few darker streaks where I cut across the car park. It's the only part of my life that looks neat on a map.
In the first week of October, the heatmap began to show something new. A small, intense spot appeared in the middle of the reservoir, where there is nothing but water and a single buoy. The app's text said: *High activity detected. Session location unclear.*
I assumed the GPS was drifting. I checked the device. It was fine.
· · ·
**RunTrack — Session detail, 6 October, 06:12**
*Distance: 5.02 km. Time: 31:40. Pace: 6:18/km.*
*Route: Reservoir ring, clockwise.*
*Note: 14 min spent at coordinates 51.3418, −0.2107 (reservoir, centre). Heart rate: resting. Not moving.*
· · ·
I hadn't stopped at the centre of the reservoir. I'd run the ring, as always, and then I'd gone home and showered. But the app said my heart rate had been steady at fifty-eight beats per minute for fourteen minutes while I stood at the centre of the water.
I thought about the buoy. It was the only thing out there. I'd looked at it every morning for two years and never once thought about why it was there.
· · ·
**RunTrack — Session detail, 9 October, 06:08**
*Distance: 5.11 km. Time: 32:02.*
*Route: Reservoir ring, clockwise.*
*Note: 22 min at coordinates 51.3418, −0.2107. Heart rate: resting. Companion detected (signal from unregistered device, 4 m).*
· · ·
The companion signal was new. My own phone is the only device that pairs with the watch. An unregistered device, four metres away, at the centre of the reservoir, where nobody can stand.
I went down to the water that morning and stood at the edge of the bank. The mist was low, and the buoy was a grey dot a long way out. I could hear something splashing, quite lightly, in a slow rhythm that matched my breathing.
I did not go in. I went home.
· · ·
**RunTrack — Monthly Activity Report (automated note, 10 October)**
*Your heatmap has changed. Your most-used route is now a straight line from your front door to the reservoir centre, and a second straight line running back. Route frequency: 22 sessions. All sessions began and ended at the same location. Please check your device settings.*
· · ·
**Journal — Joel Park, 11 October**
I've been trying to work out what the app thinks I'm doing. The map shows me going out every morning, and coming back every morning, and the middle of the route is always the same point in the water.
I asked my sister Ruth to look at the map on her own phone. She said it showed a single bright dot, very dense, in the middle of the reservoir, and a line leading to it from our street.
Then she said, "Joel, there's a second line. Starts at the reservoir and goes to the house on the corner. It's the same colour. It's the same timestamp. It goes to your bedroom window."
· · ·
**RunTrack — Session detail, 12 October, 05:58**
*Distance: 0.00 km. Time: 00:00.*
*Route: Home (bedroom) to reservoir centre.*
*Note: Heart rate: resting. Speed: 1.2 km/h. Companion detected (signal from unregistered device, 0 m).*
· · ·
I woke up at 05:58 with the watch on my wrist, and the strap was buckled tight, and the screen said I was already walking.
I was standing in my bedroom. The window was open and the curtain was moving in a breeze that came up off the water. My trainers were on, double-knotted, the way I always tie them. I hadn't put them on.
The room smelled of pond water and damp cloth. On the floor beside the bed, there was a line of wet footprints, leading to the window. They were bare, and very small, and they stopped at the sill.
Below the window, in the street, a line of pale mist ran from our front gate across the road and down toward the water, the way a route looks on a map when you've run it so many times that the ground has learned it.
· · ·
**RunTrack — Monthly Activity Report (automated, 31 October)**
*Your heatmap shows your most-used route. It is one point in the middle of the reservoir, very intense, and it does not move. Your sessions are now recorded as companion sessions. Your companion has completed 31 sessions this month.*
*Athlete: Joel Park (companion). Sessions: 31.*
· · ·
**Note from Ruth Park, 1 November**
Joel's flat is empty. The watch is on the kitchen table, face up, and its screen says the route is complete. The bedroom window is open. The curtain is wet.
I went to the reservoir this morning, at dawn. I walked the ring, the way Joel always did. At the centre, a little way out from the bank, the buoy was bobbing gently, and beside it, very still, a pair of running shoes was floating on the water, double-knotted, the laces dry.
I took a photograph. The app on my phone gave me a notification before I'd put it away.
*Your heatmap has changed. You have one new companion. Please complete your route.*