I have been getting PRP knee injections in both knees for over 10 years which allowed me to ride my mountain bike 4 to 5 times a week and work out with weights on a regular basis. As time went on I found the PRP was less effective and not lasting more than 10 months. It has been over 10 months that I tried the A2M knee injections and I noticed a big difference in how long is has given me pain relief. I also like the fact that it is a one time injection rather than having to get three injections of PRP.