So here's a top tip - I was mid-ride last night and felt my foot slipping all over the shop!
I thought it'll be OK - ride on, and take a look when you get home. The more I rode however the more I seemed to have sideways movement on my shoe.
I ended up stopping as I actually thought there was something wrong with my pedals. Turns out it was the cleats on my shoes coming loose (even though they were tight when I left).
In case you don't know how cleats attach to cycle shoes see below:
The screws had come loose - not fallen out luckily! So I used my multi-tool (who would cycle without one) and tightened them up...
I might add some thread lock onto the screws at a later date if this keeps occurring - so take my advice - always stop if something feels different to normal!
Coming up later this week an article on essential stuff to take EVERY ride out.