Hi. My name is Sue and I have always been a thin build. I'm 5'7 1/2" and weight 135-138. My measurements are 34-30-37. Funny, because 2 weeks ago I was 34-29-35. I just turned 50 in March and now gaining alittle weight . I've never really had this problem. I'm not exercising really. I work for a top warehouse and walk from one end of the store to the other sereral times a day, but I know this is not real exercise as in running on the treadmill. My question is I have a bad back, so what kinds of exercises can I do to strenghhten my stomach and my upper arms? Also my calfs. Thanks, Sue