I just did week 5 run 2, so I guess I'm past the half way point.
I found this one hard, 8 minutes felt like a big jump from 5. I handled it ok in the first 8 mins, but the second was a real struggle. I found myself desperately awaiting Sarah telling me there was only 60s left despite the fact she hadn't even told me I'd reached 4 mins yet. I didn't stop, but I reeeally wanted to.
Now I feel there's a mental block there for the next run. If I struggled that much with 2x8 mins with a 5 min walk in the middle how can I possibly do 20 mins straight? That's a huge jump! I don't understand why you have that big of an increase and then at the start of week 6 drop down again. Why is that?