I know that as my circulatory system has changed with age, I need to wear different layers than I used to. I also find that wind tends to chill me more that it used to. So, I look for shells that are windproof up to 60+ mhp. Makes a big difference in terms of my wanting to go out.
BTW, there's no question you're getting old. We all are. The real question is if we've learned to make the adaptation necessary to continue doing the things we love.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831