Been cycling for over 10 years. I ride 3-4 times a week in the summer, rides from 2-4 hours. I sometimes do 2-3 day tours with some of those days 120k+. I'm 39 and 140#.
As it's winter, I'm mainly riding indoors on the trainer, and have done some swimming (developed some shoulder problems though, so I'm taking a break from it), plus I bike outside when the weather isn't too bad. Given that I'm no longer swimming, I want to spend 1-3 days a week doing some work on my core, and on my arms/shoulders (I have a very weak upper body...I'm 140 and can only do like 5 pushups before I start struggling). I want to start a program now that I can do until the spring (may continue it after, but only so much time...and I have time now).
Few other things I'll mention - my bike has a custom made frame and I feel really good on it (i.e., weight distribution). But a long ride still hurts arms/neck/shoulders. Been to massage twice in past two weeks as my shoulders have been really sore (swimming related). While I do lots of stretching, some of these muscles were not effectively stretched in the past, but I now have some additional stretches to do. So assume that the bike fits, I'm stretching, but now I would like to build strength so that on those longer rides I'm more comfortable.
If you can point to any programs that are: easy to understand, consistent (I want to learn and remember it without constant reference to a book), and effective for what I've described...thanks!