I think four times a week sounds great! It’s more than most healthy exercises. What’s also great is that it’s all-around exercise. But most of all, you think it works for you.
If you want to get up in more exercise, I would recommend that you take those days when you don’t have “organized” exercise that you take a walk, preferably a little warm so you get a little warm, and with advantage in forests and soils, where the underlying is a little more varied.
Eric the Frenchman