Minimum TRF length in the runners, however, was inversely related to their years spent running (r = −0.63, P = 0.007) and hours spent training (r = −0.52, P = 0.035). Therefore, since exposure to endurance running may influence minimum TRF length, and by implication, the proliferative potential of the satellite cells, chronic endurance running may be seen as a stressor to skeletal muscle.
Initially found through conditioningresearch.blogspot.com.

Markus, and anyone else wondering about interactive performance regressions, NEW_FAIR_SLEEPERS is modifiable at run time; just run
echo NEW_FAIR_SLEEPERS | sudo tee /sys/kernel/debug/sched_features
grep –color=tty NEW_FAIR_SLEEPERS /sys/kernel/debug/sched_features
(Ubuntu mounts linux’s debugfs at /sys/kernel/debug, not at /debug like you see referenced on the lkml threads talking about this.)
To enable for every reboot, put
echo NEW_FAIR_SLEEPERS > /sys/kernel/debug/sched_features
in /etc/rc.local, or whatever.