Country Joe, I only took up cycling last August (not racing just local rides and occasional tour). For the last 20 years I've been more of a swimmer (I'm 57). I love my swimming and it keeps me really fit, as fit as I thought I wanted to be. I now also love the cycling and it has improved my already excellent fitness. I combine the two and feel great - absolutely no downside at all. To me they produce 2 different kinds of physical feelgood and also a combined feeling of wellbeing.
So combine the 2 and ENJOY. p.s. every sunday I cycle 6 miles to the baths, swim 2 miles, and cycle back again. I absolutely love it and so look forward to it. I consider myself really lucky to be able to do this. All the best. Ron.