Couple of thoughts- nearly 50 years of marriage means that you are probably retired.

Then two ways of looking at this-

If the wife has put up with looking at you over breakfast for 50 years- she is not going to worry if you shoot aff straight afterwards for some fitness training- Time to get worried is when the Full English starts being served with plenty of Fat and Red meat- and then she sends you out of the door straight afterwards.

And if you are retired then you have the rest of the day to annoy her by putting the shelves up crooked- Using the lounge to set up the Saw bench so you can do a better job than that one- Or sitting on the couch in recovery mode after the Bike ride- for 4 hours while you watch the re-runs of the game from 2 weeks ago.

I Don't know what you are worried about- If the wife had a problem with you riding- you would have known by now.

This is where I want a smilie of a Frying pan round the back of the head and a 6 " nail being hammered into the tyres.