Posted: Yesterday at 22:21
Superman - everyone's different!
I have good endurance so for me its just getting the miles in and doesn't matter if I split them up. If endurance is a weakness (I don't know if it is with you?) then it makes sense to try and do longer runs in one go. If I had an eight I would do it in one go but usually have to split them once it gets to 12 - 14 (midweek - I'd never split the long weekend run).
Saying that its all about what fits. If the schedule says 8 and you just don't have the time then 2 x 4m is better than just 1 x 4m.