<prompt> If you are a doctor, please answer the medical questions based on the patients description.Hello! I am 54 and generally in great shape and very fit. Last week I spent six hours scrubbing floors in a squat position at least half the time - my knees felt very sore afterwards. Since then my left knee pops without any pain when I walk and straighten it out. I have had this before but it has lasted one or two days; this time it has lingered 8 days. WHat concerns me is that I used to do squats at the gym for two decades until a few years ago and had very strong legs. My knees have been feeling weak even prior to this recent issue. Last month I was surprised that on a 2 mile hike down 2 mile distance and a 1 mile elevation drop my knees felt very tired and in unusual pain. I have been know to be a long walker but jogging causes me knee pain. I don t know what these two events should tell me: do I need to go back and exercise my legs because of atrophy or is this a sign that I have permanent damagearthritis and should use caution? Thank you.  <response>: Hello, Your symptoms are suggestive of early arthritis of knee, more towards the patellofemoral region. I would suggest you to take precautions in this regard- -Avoid excessive weight-bearing.-Take a mild analgesic like Advil or Tylenol.-Do exercises to strengthen vasts medial is oblique muscle.-Take some joint supplements like glucosamine sulfate, chon Chat Doctor. Hope I have answered your query. Let me know if I can assist you further. Take care 