Right, here's where I'm standing at the moment.
Spoke to a friend over Christmas who has entered the Henley Tough Mudder in April.
"That'd be a good warmup for the one in Northampton" I thought.
I hadn't really started running properly at that point and I recently saw a poster advertising a local half marathon on my birthday in March. So I entered and got my new 'barefoot' running shoes on and started to train.
Running on the balls of my feet is not something I'm used to, and after running I could feel my calves getting really tight. I really like the shorter stride pattern and being lighter on my feet with the barefoot running, but my calf muscles definitely weren't liking it, no matter how much I tried to stretch them.
Four sessions into my training, on the final straight when I was feeling really good, I felt my left calf ping. Not only could I not finish the run, I could only just walk!
No running or cycling for ten days while I rested, but last night I managed to put nearly four miles in and it felt good. I've reverted back to my standard running trainers, albeit with a mid foot strike instead of my old heel strike.
Done some more reading on barefoot running and some suggest doing shorter training runs in them to get used to it so I'm now going to be mixing up my footwear to ease myself into it.
By July I should be raring to go!