Maybe try ridewithgps and see if it gives you a comparable/realistic elevation data/profile. I don't know how they all get their data but in my experience ridewithgps is better than mapmyride
I trust ridewithgps better than mapmyride myself. I've heard that mapmyride averages the grade so the elevation gain actually appears lower. It's not to be deceptive on mmr's part me thinks but it is the belief that it may be more accurate to average on mmr's part.