Why do the directions alternate on this indoor track with respect to the days of the week?
A)So people don’t get bored
B)It wears out your hips/knees evenly.
I know that sounds odd, but when (25 year old) sister was having some really major hip issues, that required surgery, they asked her about her running habits. They told her that when she goes running, she needs to run her normal path, then turn around and run back on the same side of the sidewalk. A lot of people will run one way, then cross to the other side of the street or sidewalk and run back and the means that for their entire run, the same leg is always low (since the roads/sidewalks are sloped to shed water). Staying on the same side means one leg is low one way and one leg is low the other way.
If this track is sloped around the corners going in different directions every other day will keep you even. If it’s not, then maybe it’s just so you’re not always turning left or always turning right. Again, to keep the wear and tear on your body a bit more even. Or, (to be a bit more positive) to keep stretched and flexible on both sides and to work all your muscles on both sides evenly.
I vote for B.
Our YMCA has a track like that, and I have run a few thousand miles on that surface over the years. It is a small track built around the perimeter of the basketball gym, a ten mile run is 180 laps. That means 720 fairly tight corners over 10 miles. Bad on the knees. Switching every other day helps to balance things out.
And it doesn’t help the boredom. 180 times around any gym will be boring, no matter what they do. I listen to lots of audio books.