Was it the low temperature or the toast?
Last couple of winters I find I run faster when the temperature is low, this morning was the coldest I had been out in this year but I also had a slice of toast before my run, I normally don't eat anything. So when I ran a personal best of 25m 50s for 5km today, 1m 17s better than my previous PB, I don't know if its the low temperature or the toast. ππππ