Aerobic Sustenance

Aerobic Sustenance is a single-field metric that rewards efficient, sustainable aerobic effort. It gives you one number, updated live during your activity. The score rises when you cover ground faster, sustain it longer, and do it at a lower heart rate. It falls when your heart rate climbs for the same output. In other words, it captures aerobic efficiency: more distance and duration for less cardiac cost. How it is calculated: Score = 1000 x (average speed x log10(1 + minutes elapsed)) / average heart rate The duration term uses a logarithm, so early minutes count heavily and the score stabilizes as your effort settles into a steady aerobic rhythm. This makes it a useful gauge of how well you are holding a pace, rather than just starting fast. You can use it to compare aerobic efficiency across runs, rides, or hikes. You can also use it to hold a sustainable pace instead of going out too hard, or to track improvement over time at the same perceived effort. To set it up, add Aerobic Sustenance as a data field to any activity that records speed and heart rate. It requires a connected heart rate source, either wrist-based or a strap. There is no configuration, no permissions, and no data leaves your watch. Aerobic Sustenance works across Garmin watches and Edge cycling computers.