My suggestion is to do as you say before breakfast in the morning, because your home can only have good air if you open the window. The air in the morning is the best, even if there is sunshine, it will not be very strong. Proper sunshine is also conducive to the formation of calcium in the body. Moderate exercise in the morning can make your breakfast delicious. A good breakfast is very beneficial to your health.

Originally, I wanted to advise you to exercise moderately after dinner, but it seems that you have a good regimen and have proper exercise after dinner, so morning is a very suitable time for you.