Hi,
On days with kids at home or long work shifts it’s hard to do a full long ride (or run) some days, but splitting it into 2 and doing half morning half evening/afternoon can work better.
I’m guessing this is not ideal but as long as it’s not every week how detrimental is it to training? I am doing Level 0 Half IM
It’s not ideal to split longer sessions as this does shift the training outcome a bit when you do them as 2 shorter sessions. However in saying that doing the workout split into 2 sessions vs just doing half of it is a better outcome for your progression. So if this is a way for you to get the training done on busy weeks or around your schedule occasionally then go for it.
The main things that will be detrimental to your training are lack of consistency, and going to hard in easier sessions.