Instruct: Classify Amazon reviews into positive or negative sentiment
Query: WOW

For a 20 minute workout, this is pretty tough. I work out quite often,about 3-4 times a week, and found myself out of breath not even half way through this work out. Jillian is tough, and doesn't let you rest. Even after doing level 1 about 4 times, I already feel a little stronger and leaner. I recommend this video to any one who wants to lose weight.After doing the Level 1 workout, I could definitely see why the video is called "30 Day Shred". I could barely walk the next day. My calves hurt so bad!