I am 74 and have been experiencing blurred vision, confusion and orthostatic hypotension while playing strenuous beach volleyball after 90+ minutes. All symptoms go away after 30 minutes rest, hydration, and food. My question is this: Is this merely the sign of hard exercise or is it harmful? All my blood chemistries, pressures, cardiac cycles are very good, I am ecto-mesomorph. However, I just started experiencing the problems in the last 8 months. Admittedly I have been getting weaker for the past 15 years.