As one gets older (I am 61), the mind changes with regard to what is important. When I was a good deal younger, I made it a priority in life to exercise, trying to satisfy my ego on the bench press and incline press. Having achieved my goals, which were rather modest compared to others, I took a new approach. It was less about the heaviness of the weights I did and more about the technique. Now that I am in the early stages of my 6th decade moving toward my 7th decade, it is both technique and reps.
Paul wrote to Timothy: for bodily exercise is profitable for a little; but godliness is profitable for all things, having promise of the life which now is, and of that which is to come (1 Timothy 4:8, ASV).
I can’t outrun age; my body’s strength, the skin’s appearance, and the bulging of my muscles … well, they all are less impressive each year. This is the way it is and will always be. While my body deteriorates, my mind, on the other hand, can stay strong in the Lord. I don’t have any physiological or neurological problems of which I am aware, so I will stay with the course of exercising my mind in the Lord’s way.