Why we all need to run:

Everyone able to run should run 2-4 times a month, but for only about 100 meters or yards, not 5 miles.

The running industry misses a huge potential market because they accept the assumption that running exercise means "run for miles".

We can prove that running 100 yards each week may keep the running ability strong for a long life.  Promoting yards instead of miles would encourage millions of new people too start running, so sales of running shoes and tread mills could multiply.

If you think "running is great for cardio" you can also get a cardio blast from a tight thumbscrew, and that does not make them great fitness devices.