I did this today too! It was colder than I expected, so I got in a brisk 20 min walk during my lunch today, definitely moved faster due to the cold! I started my walking program last Monday with 15 minutes, on 5 days. I have really enjoyed the 15 min walking video from Leslie Sansone recommended in earlier comments. I am incorporating healthier eating with this walking program as well. I am already feeling so much better, stronger and more energetic. Thank you!