After not doing much bike riding for quite a few years, I got back into it this summer. I'm 54 years old and pretty much ride everyday about 5-15 miles. Yesterday, I got up and decided to ride further. I ended up doing between 55-60 miles. I just relaxed and took my time and it really was uneventful. A little stiffness in my shoulder/neck area. I did hydrate a lot before riding and ate a couple of bananas. I also wore cycling shorts. It was on a hybrid bike.

So, I think you can do it as long as you pace yourself. Also, I took a couple of breaks just to stretch out during the ride.

I know I could have gone further, but had other things I wanted to do. The cool weather that day really, really helped...and the fact that I had no flats!!!