After finding out horsforth harriers have access to Trinity College's track on Thursday, I headed up after work. I'd cycled home so was a bit drained. I did 15mins at 2mins/400, and 10mins at 1.40mins/400. The coach turned up as I was about to finish the 3mins rest and attempt 5mins at 1.30mins/400, so I put a few questions to him.

He was telling me how if you do too much fast and hard training the body never develops the cellular biochemical conditions to generate power effectively. It's all to do with ATP and mitochondria and crap. He told me I ought to be doing one fast parkrun a month and a lot more running at about 8.30mmp based on my typical parkrun time of 20m. The way I do things at the moment, with my fast sessions and plenty of racing, my body is missing the tools to produce maximum motion at a cellular level.

It's news to me.