optional, single

—

Indicates the measured heart rate of the diver at the respective <waypoint>. The heart rate is given in the SI unit 1/s.

<waypoint>

—

<waypoint>

<!-- 48 heartbeats per minute = 0.8 heartbeats per second -->
<heartrate>0.8</heartrate>
                

<!-- 60 heartbeats per minute = 1 heartbeat per second -->
<heartrate>1.0</heartrate>
                

<!-- 93 heartbeats per minute = 1.55 heartbeats per second -->
<heartrate>1.55</heartrate>