How long has it been since you have had a chiropractic adjustment? Find a chiropractor who also knows Active Release Technique (ART - deep muscle massage). With regards to knees ... sometimes, tendons at the knees can get off track and start tracking incorrectly ... a chiropractor can also do simple knee adjustments if this is the situation with you now. Overall, a chiropractic adjustment and a deep ART massage can help you.
Obviously, your past marathon performance was related to you having gotten sick 6 days before the marathon. This time, you are in different situation.
At this point, from what you have described, your need is for the above mentioned chiro work and rest and recovery. The taper thing goes out the window in favor of rest and recovery. Yuan fen.
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