Instruct: Classify Amazon reviews into positive or negative sentiment
Query: 30-Day Shred - tough workout

I plan to use this workout about 3 times a week this winter, when I can't get outside to run. I've done level 1 twice since I bought it, and it's a pretty good workout. I was a little sore the next day, and I was already in pretty good shape. I think I need to do level 1 & 2 to really replace my run though. Jillian Michaels seems a little uncomfortable at first, but then her personality (while not especially warm) does come through. She is very down to earth and encouraging without being phony or perky (both of which I hate!). The ladies working out with her are in great shape - especially Anita, who I've seen in other workout DVDs.