The pain of knowledge

Today I ran about 10.5 miles (according to Google maps) here in Burbank while visiting my parents. I did bursts up any hill I came to and kept my heart rate in the 140s-160s. During a recovery downhill, I reflected on the easy runs I used to take in college. I'd go run my 5 miles (I can still visualize many of the landmarks in my mind) and let my mind mull through classes and stress. I'd enjoy the run and come home, stretch, and feel good about my exercise. I was a runner.
Then came marriage to Rich and discovery about intervals, the acquisition of a heart rate monitor, the use of a power meter, training plans, etc. My efforts were no longer solely subjective. I could now measure and compare how I was doing. I became wiser in the sport, but training also became more painful. I now train harder, but recover quicker. Mentally it is tougher, but I am now competitive.
During today's run, I realized that I can never go back. Every run I do now has a purpose-- hills, distance, speed, etc. There are occasional LSD runs-- long, slow distance runs, but generally my training is more focused. With knowledge has come sacrifice, but also great blessings. I think this is true in life-- Once I received my nursing license, gone were the days I was just a medical helper and could pass off errors to the nurse I was helping. I was now responsible for my actions and the actions of those working under me. Once I made temple covenants my life has changed. I feel a great responsibility to make sure I am living up to the covenants I made. On the other hand, with knowledge and responsibility has come great opportunities and joy.