Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Up for a Challenge? Here it is.

I love Jillian Michaels workouts. This one is the best one yet. I did it once before but was not watching my diet. So, I didn't get the results that I was looking for. This time I'm working on my diet and doing the workouts. And, I've already lost four pounds in two weeks.The workouts are tough but manageable. There's a modifier in each workout to help you if you're not up to doing the full exercise yet. I love how Jillian motivates you to get through the workouts. They're only 30 minutes each which is short enough for me to do before work.Be prepared to sweat and get your heart rate up even with the first week's workout. Stick with it and you can do it!