And the same applies to saddle positions as well.
After all the health issues I was finally able to get back on the bike after about a 3 months absence. I needed to replace my cleats and in doing so I noticed that one cleat was all the way towards the arch of my foot while the one on the other shoe was all the way forward. Since my preferred position was to have the cleats closer to the arch of my foot I speculated that somehow the one furtherest away from the arch had moved over time.
Then again maybe not. I moved the one furthest away from the arch back closer to the arch and within 2-3 rides I developed a severe pain in the achilles. It was very painful during the ride and would remain painful for 2-3 days afterwards. I could even feel the tendons sliding up under my skin and down as I moved my ankle due to the swelling.
After continuing to have the pain for several weeks I finally moved the cleat a little futher away from my arch and like magic..........the pain didn't resurface. I only rode 40 miles with no hills but normally it would really start hurting around 10-15 miles so I'm hoping it's fixed for good. What I did notice was that I picked up some slight additional "pain" in my right knee that still has some fluid and swelling on it. Hopefully it is just adjusting to slighting different pressure points from pedaling.
It's amazing what even slight adjustments to cleats and saddle positions can do. I've probably ridden 10,000 miles with it the previous way with minimal issues. A good lesson on "Don't mess with happy"!
On the other hand--if you're having pain start with very slight adjustments--sometimes it doesn't take much to feel the difference.