I work haphazard runs of 2*12 hour days then a swing into a single 12 hour night followed by 1/2 days off depending. I find I can manage high volume sweetspot base with a little shifting of workouts but once it increases to build or peak, I find the intensity very difficult to manage, easily tipping into to insufficient recovery. I get 3-4 hours sleep post night then can do an afternoon sweet spot session with a greater RPE than normal but typically complete-able. I’ve tried in the past to race or do higher intensity work and I find the effort depletes me to such a level I’m still recovering two days later. I treat pre nights as a normal day so I’ve raced/done big TR sessions and done long endurance outside with little predictable effect on either my night shift or the day after.
Ultimately though working nights makes me slower