Those long rides always have taken a lot of training for me and that involved Gym and Cycling to get the fitness required to do them. Up till 2006 I used to do a 100 mile- 10,000ft offroad ride in one day. I can assure you that you have to be fit for this ride and I used to train for that one ride for most of the year. Couple of evening rides all year round- 60 odd miles at weekends and winter was the Gym aswell. After the ride it was do a few 65 mile offroad enduros or a 100 mile on the road just to retain fitness. But It was that 100 miler that gave me the goal and I worked for it. It wasn't a chore but it was hard work.
Then in 2006 I stopped the serious offroad and went road. New challenge now- and the main one was adjusting to road bikes and riding. That challenge kept up till the end of 2011. I blame it on the weather but in reality it was me. I lost the enthusiasm and could not be bothered to go out on a Sunday in the rain and the wind and the cold and gradually the impetus went out of my riding. Still managed a few Metrics that year and a 100 miler or two but the enthusiasm was not thre. last year and I entered a Metric early in the year and turned it into a 100 miler by riding back from the finish and a few miles before the event. That made me realise how unfit I had become and I had every intention of correcting that this year but it hasn't happened.
So I am in the same boat as you and sinking fast--Or I was. There is a big National ride next year and I have got a place. I will have to be fit for that ride. Cutoff time for the 100 miles is 8 hours and I will struggle to do it unless I get off my backside and do some work.
Since getting that place on the ride- I have my old enthusiasm back. It will not take much effort for me to get fit again- just a couple of thousand miles and some effort-or a lot if I really think about it. I may even take up the Gym membership again so I will not catch pneumonia on the cold wet days that I should be riding but won't as it is too cold- too wet and too windy.
I may be peculiar but I require motivation to get out and do a boring 60 miler when I don't really WANT to. I know I NEED to but that Goal of doing the ride next year is going to overrule what I want to do.
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How long was I in the army? Five foot seven.
Spike Milligan