Read Grin and Bear It: The Influence of Manipulated Positive Facial Expression on the Stress Response", which says smiling reduces recovery time from stress and lowers heart rate and that smiling has been associated with: reduced stress hormone levels (like cortisol, adrenaline, and dopamine), increased health and mood enhancing hormone levels (like endorphins), and lowered blood pressure.
And this response to the above study makes a good point."It's extremely difficult, if not impossible, to smile while running 'too hard.'" So smiling also slows us down.
Smiling has been shown to release endorphins and serotonin. This can be a benefit while running, especially in moments of stress.
"Since the biggest challenge in long-distance running isn't physical but mental, smiling "ensures that long-distance running will be much, much easier," says Ms. Gorjanc, a co-founder of an online resource for women runners called "Salty Running."
Another column that consolidated studies (FYI: That's a link to a Forbes article. If you're having trouble reading it, try here (though Forbes don't seem to have maintained the article's internal links very well)). The Forbes article mentions a study published in the Journal of Personality and Social Psychology and illustrates that people who smiled after engaging in stress-inducing tasks showed a greater reduction in heart rate than people who maintained a neutral facial expression.
I searched out my old faithful for this form and OH MAN has the meme gotten out of control. Just a smattering of "ridiculously photogenic runner":

Second half - Running Tangents
The second half of this form is "run smart". Measured courses (races, marathons, half-marathons, etc.) are measured for the shortest runable distance, from start to finish. Other people in your way and bends in the road can increase your total running distance. The former requires courtesy but the latter requires tangent running.

Too simple? Well let's make it even more complex. Head for the furthest convex apex you can see a direct path to!
Third half - Healthy Activity
Yes, this is the third half (bet you did not think there was a third half of anything) intentionally left to the last and with no form week of its own. I've been trying to find something to balance the other 18 forms, which all encourage more, more, more, do-more, without much encouragement to those who have to take things slowly and carefully. Jeff found an article, (thanks for finding this, Jeff), that evaluates the validity of treating BMI (Body Mass Index) as a cause of ill health, and not as a measure, the control of which, makes you more healthy. BMI could be adjusted by (a) increasing height or (b) reducing weight.
(a) Increased height is difficult to achieve without using The Rack, which use has fallen out of favor since the middle ages (can't imagine why but, here we are).
(b) Reduced weight is more easily achieved but there was a study trying to correlate the weight aspect of BMI with longevity. Though weight loss has been chemically achieved, it is unclear that this weight loss actually correlated (or correlates) with an increase in longevity. There is anecdotal evidence (if there can be such a thing) that, though weight loss benefits the health of people who do not exercise, the loss can be detrimental to those who do (or are trying to) exercise. Additionally, if you're using exercise to lose weight by replacing fat with muscle, it should be noted that muscle is more dense than fat. You may actually gain weight by exercising - none of which is bad.
Adding more obscurity to the utility of BMI in studies, it should be noted that BMI is most often calculated using the height of an individual, which decreases with age, so BMI, itself, is not a great metric when age-shrinkage is not taken into account (which it generally isn't).
Looking further into "The Science"TM it appears "increasing fitness" is much more important than "losing weight" as a target. This paper (linked here) examines this really well. There are many other reasons why losing weight, as a target, is a long-term fitness inhibitor. Short-term, weight loss works well, but by itself (that is, without moderation or care), weight loss can cause metabolic stress and lead to other factors that result in a seesaw effect.
What about those individuals who cannot run (running being our main focus) e.g. those who suffer with (among other things):
There are many other conditions that would prevent running as an exercise. Being active (with being "More Active"TM as a goal) seems to be something to strive for. Being active appears to correlate better with getting fit than chasing a BMI.
How about this as a Mantra (or Mission Statement) just to tidy up at the end of our weekly forms:
If you can run, we'll try to help you run safely
If you can't run, walk
If you can't walk, cycle
If you can't cycle, swim
If you can't swim, roll
If you can't roll, cheer
If you can't cheer, we'll cheer for you!
Be Active (with care)!
See you on Wednesdays.
Related WFR Topics (Everything):
"Countering the Bounce" #1 (bubbles),
"Bended Knee" #2 (bubbles),
"Short Strides" #3 (bubbles),
"Arm Swing" #4 (bubbles),
"Relax" #5 (bubbles),
"Quiet Feet" #6 (bubbles),
"Ground Contact Time" #7 (bubbles),
"Forward Tilt" #8 (bubbles),
"Hips" #9 (bubbles),
"Head Posture/Gaze" #10 (bubbles),
"Breathing" #11 (bubbles),
"Passive Stride Recovery" #12 (bubbles),
"Shoulders Back!" #13 (bubbles),
"Run Tall" #14 (bubbles),
"Avoid Kneesles" #15 (bubbles),
"Free Your Head... Unplug! #16 (bubbles),
"Recovery #17 (bubbles),
"Hands" #18 (bubbles),
"Smile, Tangents, and Activity" :-) #19 (bubbles).
Related WFR Topics
"Relax" #5 (bubbles), "Recovery" #17 (bubbles).
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