If I have a 10% EF, why don’t I have loss of energy?

I was recently diagnosed with dilated cardiomyopathy. I was told that the lower chamber of my heart was at 10% and should be about 45% or higher. I have a-fib and I understand how all this comes together… the part I do not understand is that I have no loss of energy. I was walking 5 miles per day and have a hobby farm were I just finished shearing 50-60 goats. I have asked how I could be at 10% yet have the energy that I have always had? I was told to wear the life vest, no walking and activity to raise the heart rate. I am a 56 year old male, non-smoker (any more) and have had the ablation procedure done a couple years ago. I have asked these same questions to my doc but get a blank stare and a shrug of the shoulders. I should note the procedure that was used to determine this was to knock me out and go down the food pipe to observe the back of the heart. Any of your thoughts would be greatly appreciated.

Submitted by John from New Holstein, Wisconsin on 10/09/2013