Our practice is that you can pick your own consistent start time between 7-9. You can also do things like compress your week to 4 10 hour days or add an hour to get a day every two weeks. We don't want you in the office after 6 on anything approaching a regular basis. You can vary the time by day, which is common for childcare or other outside demands on your time.

If your habit is a 5 hour start window for an 8 hour workday, you're not going to work out.

That window works well around here, zero problems. And I don't have to be consistent, I can decide when I come in the morning.

Is there a reason they need to be in the officd at all?