I have been working out with a trainer 2 days a week for over a year. Whenever we do abs I find that I sometimes experience severe spasms in my upper abs. 5 years ago I was diagnosed with a hiatal hernia which I was unaware of and wonder if this could be the cause. I want my workouts to include abs but need to know which ones to stay away from and what other causes may be the issue. If anyone has experienced this too I would like to hear from you. Or if you have suggestions on specific ab excercises I should do or not do I would like to hear that as well.