Inspired by this press report Apple Watch can detect symptoms of Parkinson’s disease, study reveals | The Independent and the mention of altered gait as a potential early symptom of Alzheimers had me scrolling through my Apple Health App data for the sections “Walking Asymmetry” and “Double Support Time”. The former is a percentage comparing the relative speed of left and right legs and the latter a measure of how much time each foot is placed om the ground when walking.
Generally both these metrics are okay with Asymmetry at 0% and Support Time between 0% and 40% (which are the bounds for normal walking gait). However, on three distinct occasions I found average Asymmetry of between 30% and 50% with a peak of 100%!!! Checking my diary I see a commonality between those occasions; I was walking on muddy park/farm land and badly maintained country footpaths. There are a few occasions prior to that when my Asymmetry was just into double figures with one of them being a visit to a park.
I do not believe that this occasional sudden increase in my asymmetry can be attributed to Alzheimers but it does raise questions of how can I prevent it and why walking in parks and on muddy ground causes it. Late last year (2023) I twisted my left knee badly and required intervention from a physiotherapist including a steroid injection in January of this year (2024). Now I have to go search the STEM literature for ways to adjust my gait to prevent such outrageous numbers in the future.