Found a training plan for a 10km trail race for 10 weeks. Figured that would help me to kick start my fitness again without being too laborious - facing a half marathon straight off was actually too much. Plan starts with a test mile - not an all out fast as you can mile, but run at a tempo HR. I was going to pick 175 bpm, but my HR was so high on the jog up that had to go for a rather ridiculous 185. Was plodding, really slow, and it shows in the time - 7.35. So that's how fast I ran 26 miles at a HR of 175ish 2 years ago! Man...that's depressing. But if I can stick to it I should see improvements there pretty quickly - not only due to improved fitness but better adaptation to the heat etc. Now we have air con I am already feeling far more energetic, so hopefully things will start to improve.