# Study 000M Plain Language Summary

This study asked:

`Did the system adapt partly by changing the kinds of training environments and support patterns it used most successfully?`

The answer is:

`Yes, probably.`

As the archive progressed, successful running became more concentrated:

- running became a much larger share of structured activity
- treadmill running became an even larger share of total running
- outdoor running became a smaller share
- low-burden outside running only stayed successful in very specific supported states

At the same time, the study does **not** say:

- treadmill is always good
- outdoor is always bad
- all support ecology disappeared

The better answer is:

`the system seems to have reorganized its ecology around the conditions it could use most successfully`

That is why ecological narrowing may be part of the compensation phenotype rather than just a side effect.