Hi from a total newbie

Hi, just thought I'd introduce myself, I'm Owen from Cumbria in the UK and I've just signed up to take part in my first triathlon.

I'm 35 and a little(lot) overweight.
The Tri is in mid september and I've been persuaded to enter by my friend who has completed a few in the past and is a confident and quite fit athlete.
It's a sprint tri 400m swim, 28k cycle and 7k run, now I'm conifident at the swim and cycle aspects but I'm not much of a runner, the route is mainly flat but about 1-2K of the route crosses a shingle and rock beach which I'm not looking forward to due to some nasty ankle ligament injuries from the past. I guess I've got a question in that would it be frowned upon if I walk/jogged over the beach section of the run? I'm confident that over the next 6 weeks to the race I can build up to a reasonable time, but I'm concerned I'll injure myself on the beach and don't want to disrespect anyone or the event by walking if it's not the done thing

If you can offer any advice or support it'd be massively appreciated.


Thanks
Owen