I am only a beginning runner but Sat and Sunday didn't workout for me either w/ working in longer recovery days.
I scheduled my long run for Tuesdays.
I don't see why you can't do them any day you choose - I think they are scheduled weekends because that is when most people have the block of time to do them.
What she says! I'm gonna be in the same boat soon.
I'd rather be swimming...biking...running...and eating cheesecake...
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2008 Cervelo P2C Tri bike
2011 Trek Madone 5.5/Cobb V-Flow Max 2007 Jamis Coda/Terry Liberator
2011 Trek Mamba 29er