Instruct: Classify the given Amazon review as either positive or negative.
Query: Excellent and safe exercises

As someone who has severe osteoarthritis, I needed safe exercises. This DVD has both beginner and advanced exercises and are explained well enough to prevent injury. The explainations of the different muscle groups that support the knee were very informative. The only downside of this DVD is the beginning infomercial. I usually just put in and then change into exercise clothes so I don't waste time watching it!