Quoted:
My out-of-town gym has a townie that I've watched for many weeks do dips with a weight belt. Every week he straps on a 45 and 25.. He gets on the dip machine and without exaggeration, leaves his arms locked out and kicks his feet like he's a dolphin. His arms never move but he strains as if he's doing dips and kicks, his feet go up and down with his head bobbing forward to the motion of his kicking feet, but his arms never change lock.
The first few times I gave him the benefit and thought maybe he was working lockout, but I've watched him do this same thing every Tuesday night for the last 6 months.
That's analogous to how my mom was doing "pushups" until recently. She demonstrated for me and it consisted of starting in a plank position, kind of slumping down while slightly bending her arms, then de-slumping to the start position.
I showed her how to stand a foot or two from the wall and bend her arms to touch her head to the wall pushup-style but with far less weight. Then once she can do that perfectly for a lot of reps she can move back a few inches to make it harder, and so on. Maybe someday she'll be able to do a proper pushup on the floor but in any case going against a wall and eventually a countertop with good form while actually bending her arms and holding her body straight (and not rushing through the rep) will do her a lot of good.
She's 72 years old and because many of her contemporaries (including my dad) rarely get off the recliner she's gotten too much reinforcement about her sloppy half-assed workouts being "not bad for an old lady" or whatever. Even in classes down at the gym supposedly run by fitness trainers. I'm trying to convince her that anyone at any level of fitness will do better by doing things right.