for the 1st time in 6 weeks I worked ab's. I did decline crunches,knee raises and machine ab's. I did this Saturday and i am in pain today. It hurts to bend over, cough,etc. Is it just because i have not worked them for awhile. i hurt my forearm so I took 6 weeks off. I worked chest and biceps today and it killed me to get up and down. is this normal?