Rob,
When Rick and I were in our late 40's, we joined a gym for a while and went every day for three months prior to the sailing season. We had a regimen we did with all the different weight and resistance machines, as well as free weights. It made a TREMENDOUS difference in our sailing that summer, both in terms of strength and endurance. We felt much stronger and much more in control of ourselves and of the boat. We stopped doing it because the gym did not open early enough in the morning, so it took a huge chunk out of our work day -- half hour each way to the gym and an hour of workout.

Of course, all that stuff can be done at home, too, but it is so much harder to get motivated and to focus and to shut out the distractions.

Anyway, we felt that the weight training was much more helpful specifically for our sailing than aerobic-type exercises.