I have a question for those of you more experienced than I (which encompasses the vast majority posting on the WISH board). So I've been walking very regularly the past 3 weeks. Outside and on my treadmill. It seems that I feel great the first 10 minutes of my walk. All systems full steam ahead. Invariably at the 10 minute mark, my shins start hurting. This lasts for 10 minutes and then at about the 20 minute mark, it eases up. I bought new shoes a couple of weeks ago and it doesn't seem to have helped in that particular area. Any suggestions on what I should do?