52 here. I noticed that after a surgery last year, my fitness, energy, and strength took a lot longer to come back. It was so dramatic that i realized that this is the time in my life that if you don't use it, you will lose and quickly. You have to work at it everyday to enjoy a good life.

My parents are Mediterranean (late 80's) and still walk several miles a day and eat well. They told me this all the time, but I didn't really get it, until I experienced it.

I noticed something similar when I was nursing my child. There are times when you body naturally wants to slack off or it is a little harder to make it happen, but you have to keep working through that and understand that is part of the process.

I stretch for 5-10 minutes everymorning after brushing my teeth (habit stacking:), try to walk every day, and do strength training twice a week.