It becomes harder still when you pick up niggles almost as soon as you set off.
But a few minutes of grimacing paid dividends for our head of features CHRIS CORDNER in his latest training stint.

STIFLING conditions were predicted.
The weathermen were forecasting scorching temperatures later in the day which is why I set off for a training run at 6am on a Sunday for the second week running.
At least, that's my excuse. That and the fact that I am rubbish at having a lie-in.
So up I got and began running.
I was determined to run well and be in tiptop shape by the time it came to my next training run in the presence of my personal trainer from Springs Chris I'Anson later in the week.
The first mile or so was a doddle. The breathing was fine and I was going well.
Then I started to feel a twinge in my calf and it just would not ease up.
I tried slowing the pace and that seemed to help.
But the twinge was not disappearing completely and I was worried that I could do myself a serious injury if I kept on going.
I persevered at a slow pace and decided that, if the pain became too overbearing, I would call a halt to the proceedings.
It never did.
I kept going and the pain subsided after five minutes or so. Let me get this straight. I am not advocating that people should run through injuries. Far from it. If you have a strain, pull or injury, get it sorted.
But I had a gut feeling this was not too bad so I went with my own instincts.
In the end, I was running smoothly and managed a seven mile-plus run up and down the hills of Durham in 72 minutes.
I felt I had achieved something important. I was not letting each obstacle bring me down.
It's a step in the right direction. I just have to make sure they are not steps towards injury.