Yea, I'm reasonably fit. I walk a few days a week and am not overweight at all but I haven't been doing any cardio exercise for months. I am seeing an OB for a 7 wk scan next week so am not sure whether this would be too strenuous for me. Believe me, I don't want to risk anything with this one and would rather 'lie' than do something silly. I wish I knew how tough the walk was...