Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: great aid at the gym

For the longest time I've wanted one of these, especially since I learned that the machines at the gym aren't really that accurate as to measuring your heart rate. So when the machine would say I'm reaching my optimal workout rate, I was really far below or above. With this little gem tho, I can get an accurate reading to insure maximum burned calories.It fits perfectly, even with the chest strap. No complaints so far, I've even sweated perfusely onto it, and it still functions great. And as a testament to it working correctly, I've lost five pounds in three weeks after using it, compared to zero pounds for the month prior to having it. It's a great aid in my weight loss!