I learned the hard way that it is essential to do cross training to maintain running capability. I ran a lot thru the period 1985 - 2000. I was racing once per month at various distances up to half marathon, I was running 40+ miles per week. I joined a running club in 96 and trained harder, improving my race times considerably. London Marathons in 96 and 97. Off road long distance runs with club friends, cross country races thru the winter.
You get the picture I am sure! Anyway, all I did was run, run and run (oh and a little cycling). No other type of training at all.
I would get what I considered to be niggly injuries from time to time and generally i would 'run thru' these. By 2000 I was in a very bad way, with back and leg problems that just would not go away. Eventually I stopped running altogether, something every runner dreads.
In 2003 I discovered the Gym. A nice small health club with a very mixed membership. I have been going now for 3 years. 2-3 times per week. I use the CV machines for about 60 mins and the resistance machines for around 30-45 mins. This has helped me to build up strength in my upper body as well as improve my CV system.
This year I have re-started running and am pleased to say that I have not triggered my old injuries. I run 3 times per week, 2 x 50 mins and 1 x 70 mins.
I am convinced that I should have been doing some strength work all those years that I was running, then I probably would not have had to stop running altogether. Gym work is now part of my exercise regime. I enjoy it, maybe not as much as running, but I enjoy it all the same.
John