Personal experience, N == 1... For the last 400 days, I walked at least 10 000 steps daily every day - in heat, frost, snow or rain. Sometimes much more, so th

Personal experience, N == 1... For the last 400 days, I walked at least 10 000 steps daily every day - in heat, frost, snow or rain. Sometimes much more, so the total sum exceeds 5 million steps. My immune system has improved visibly, but all that activity didn't have any measurable effect on my weight, which has fluctuated randomly around the same set point as in the years before. I wonder whether all the putative health effect stems from the immune system improvement.