I had a pretty bad case in my right knee in April. The day I noticed it (two days after a hard ride in cool weather and the day after an easy ride in cool weather) I started ibuprofen and rest. Took six days off the bike. I then started back with the following rides over three days - 10 min low resistance trainer; 20 min low resistance trainer; 30 min low resistance trainer. No pain - so over the next five days took three rides outdoors of increasing intensity and no recurrence. Then went back to routine riding. I did some extra stretching over the timeframe but did not ice my knee.
Hope that helps.
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