I am a 62 yr old male, no symptoms and exercise everyday, bp is 110/70, crp 1, HDL 90 tchol 190 LDL 110, I am dike race ave 19-20 mph over 2 hours, bmi is 24, my ef is 45, should I be concerned. I am an exercise physiologist and have had a low EF 45-50 for the last 10 yrs.