I've done a few half marathons with my most recent one being the SF half marathon where I finished in 2:08:13, 9:47 min/mi pace. That course was predominantly flat.
So I've been asking some of the other runners from my running group about this, and I've heard a couple of theories:
- 1) Double your half marathon time and add 20%: For me, this would be 4:42:05, 10:46 min/mi pace
- 2) Double your half marathon time and add 20-30 minutes: Using the 20 minute guideline, this would give me 4:36:26, 10:33 min/mi pace.
BUT here are some stretch goals for my own amusement: