My Heart Rate Is In The 80's Sitting Down, 110

My heart rate is in the 80's sitting down, 110 when standing and feels like it's beating out of my chest at times during activities. I'm 40 years old and never had any problems and don't want to be put on medicine if I don't have to. I had a EKG laying down which was normal, but didn't take it standing up. After I eat I also have what it feels like heart palpitations. What can this be?