Dear Dr. Laura,
Imagine if you were a severely out-of-shape, overweight woman and your first exercise was trying to bench press 200 or more pounds. You could barely lift it a few inches up and down, if at all. The exercise would put tremendous pressure on your shoulder, elbow and wrist joints. It would be so hard that the correct muscles wouldn't even be firing.
This is probably what happens when your average listener tries to do a military pushup. I would like to suggest a better way! I am a personal trainer and Dr. Laura fan. I admire the way you maintain such excellent shape and inspire your listeners to take responsibility for their weight.
There is an easy way that more of your listeners can join in your pushup challenge, without joint problems.
The most severely out of shape should do a military pushup against the wall. You are correct: the body should be straight and the chest should be lowered all the way. You should engage your chest muscles as you push away. The next level would be a perfect military pushup off your kitchen counter. Next, the couch. You would gradually work your way to lower and lower surfaces until you were on the floor! This is the equivalent of slowly using heavier and heavier weights with proper form.
Please please share this with your listeners. Then pushups will be accessible to everyone and no one's shoulders or elbows will be strained.