SURMOUNTING FITNESS OBSTACLES   Some 20 years ago, completely out of shape, I decided it was time to get fit. Yet, I kept finding reasons to not begin exercising: I was too busy, I thought the workout routines would be boring, I didn’t want to join a health club. But I finally conquered my fitness obstacles after I realized what was my biggest challenge: I didn’t want to exercise cooped up indoors. So I went outside and began to jog a little, starting off at a mile twice a week. Next, I tightened and oiled the chain and pumped air...