It is a horrible idea.
(N.B. throughout this article, I am referring to static stretching and stretching that approaches the limit of a muscle's extension, before a major effort. Light, active "stretching" which more or less mimics the actions you plan on doing is a different thing.)
We have been told for years to stretch before running. As runners gather around before a run they sometimes nervously stretch. God forbid that they be caught doing nothing. People will think they aren't a real runner. (Sort of like the person coming in to the finish line at a 6 minute sprint when their overall pace will be 11 minutes.We can do the math. It's cool that you are slower.) Before a race, as the nervous energy kick in, people start doing stretches they haven't done in a decade. They push against poles and vehicles. They grab their leg and pull their shoe up to their quad. They more or less are not only not doing anything beneficial but they are probably doing a great deal of harm. (I cannot tell you how much I hate this stretch, if only because anytime
I did a news story the photographer would ask me to do that for the
pictures. I used to oblige. Now I tell them to take a shot of me
fella's blog for all kinds of sciency stuff. He echoes or is saying many of the things I have said for years.
Why am I telling you this? Because my goal has not been about getting people to run. Motivating people for brief periods of time for specific goals is fairly easy. My goal is to keep people running. The best way to keep someone doing something is to make it enjoyable and make it safe for them o do. If they are injured, they are not going to want to run. Plain and simple. (This also goes to the point of streak running but that is another day's article.)
So many runners continue to think that flexibility is the key to being a good runner. They are wrong. For our sport the key is to keep everything going in a forward motion. Our need for lateral motion is very little, even for trail runners.The most efficient runners, especially as the distance gets longer are those who exerted the least effort to maintain a pace. Those runners are often the stiffest or ate least not all that flexible.
Knee injuries, almost never caused by running, are however often caused when the ligaments are loose and allow the knee to slide and grind. Guess how ligaments get loose. Go ahead. I'll wait. (It's in the title of this article.)
Yet people continue to stretch. They also continue to smoke/chew tobacco and drink alcohol in spite of the overwhelming evidence for how bad those things are for the human body, so I guess I shouldn't be surprised. However, I hope this will help drive home the point that stretching is not only overrated but detrimental to your success as a long-term, healthy endurance runners. (Same as ice baths. Again, another article.)
So stay tight, warm-up appropriately before your running with some light jogging or other aerobic activity, and leave the stretching for the Armstrongs. (Google it, you damn millennials.)