For the TG100, it wasn;t just the instructions that were wrong I'd recommend a read of this
From what I've read online the TG100 was a complete disaster this year. I leave google to fill you in on the details.
Sounds silly, but have you emailed them? They responded fairly promptly when I contacted them last year
You should be able to complete it, but I don't think it'll be pretty. Depends what you want out of it.
If suffering isn't your 'thing' then I'd probably put it off until you're better trained
Check for tightness in your hamstrings and glutes - these will pull on the lower back. Strong core will help, do youfeel a bit 'spongey' in the middle towards the end of the race?
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