Ok so having said I run for enjoyment what has possessed me to sign up to a tough muddier !!!!! I have gone mad.
So my runn this morning 7 km to the gym. Nice. Beautiful easy and gently breathing, that was a breeze. Then upper body work at the gym - that was hard from the first bit of kit. I could only manage 3 pull ups - oh dear. Couple of minutes planking, some sit ups , mountains climbers and oh dear then the run back - via my usual hill for interval training. I was a huffin and a puffing.
Conclusion - I am too old, too mad , this is too hard, I can't even type this, my arms hurt. That said two years ago I struggled with run 1 week 1. I made c25k, I will make tough mudder. Whatch out old woman running !!!