Every treadmill logs each session for the maintenance schedule and the user's account: distance, speed, incline, time, and the heart rate off the handgrips. Treadmill 4 logs a run at three most mornings, forty minutes at a steady pace, with a heart rate that climbs and settles the way a fit person's does, on a machine in a locked gym, and its belt hour counter, which is mechanical, agrees.
I am the gym manager, and the machine logs are how I plan servicing.
How the machines log.
Each treadmill records a session when the belt starts: time, duration, distance, the speed and incline profile, and the heart rate from the handgrip sensors when they are held. The sessions go to the maintenance system, which schedules belt changes by distance, and the belt also has a mechanical hour counter on the motor that the engineer reads.
A machine that is not being used records nothing, and the belt does not turn.
Treadmill 4 records a session at about three most mornings.
Forty minutes. A warm up at walking pace, a run at a steady speed for thirty minutes, a cool down. A heart rate on the grips that starts at about seventy, climbs to a hundred and fifty, holds, and comes down.
The gym is locked at ten and opened at six, and the camera over the treadmills shows the row dark and still.
The belt hour counter on treadmill 4 gains forty minutes a night. It is a mechanical counter on the motor and it turns when the motor turns, and the engineer has read it, and it has done about two hundred hours more than the maintenance system's total from the day sessions, and the two hundred hours are the nights.
What has been checked.
The machine. Serviced, and its controller replaced, and then the machine replaced, with the old one moved to position 6 and a new one in position 4.
The new machine in position 4 logs the run. The old one in position 6 does not.
The camera. The belt on 4, on the recording, does not move. The machine's display is dark. The handgrips, which light when held, do not light. The log says a heart rate came through them for forty minutes.
The power. The gym's machines are on a timer that cuts their supply at half past ten. The log's sessions are timestamped by the machine's own clock, and the maintenance system received them at six when the power came back, as a stored session, and the belt hours had gone up in a machine with no power.
The profile.
I have looked at a thousand session profiles because it is my job, and this one has a shape I know. It is a runner, a good one, running the same programme every night, thirty minutes at a pace that would place in a club race, with a heart rate that says the pace is comfortable.
The gym has a members' board with the club runners' times on it, and the best of them, for years, was a man who trained here every morning at six on treadmill 4 before work, and who collapsed on it in 2016, on a Tuesday, at the thirty minute mark of the same programme, and the defibrillator on the wall by the door is there because of him.
What is done about it.
The night sessions are in the maintenance log and the belt on 4 is changed a third more often than the others, which the budget covers, and the engineer asked about it once and I said it was a popular machine.
The account the sessions are logged to is the guest account, which is what the machine uses when no member's card is scanned, and the guest account's history is a run at three every morning for eight years.
What I do.
I manage the gym.
The one thing I have changed is that I open at six with the lights on before I go in, from the switch by the door, rather than walking in the dark to the panel.
The reason is a morning when I walked in the dark to the panel and passed the treadmills, and 4's belt was warm under my hand, the way a belt is after a run, and the handgrips were wet, and the display, which was dark, showed, as I passed it, for the time it takes to read it, the last session's summary, forty minutes, and under it the word that the machine shows when a member's programme has been completed, which is congratulations.