What are they good for?
Digging a hole and filling it up is more purposeful. A stroll down the driveway burns more calories. Getting up off the couch demands more flexibility. Jumping up and coming down is far more physically taxing. And brain training? Well, wall sits are like learning to write by pressing your face into a letter chart.
Do not confuse "difficult" with "worthwhile."
Wall sits build endurance? Endurance at what? Okay - I'll give you down-hill skiing. But there are about a thousand more efficient and productive ways to gain strength and endurance for that. I'll also give wall sits "effort." While even the worst resistance training machines demand more strength, flexibility, and energy burn, none of them rival the misery of wall sits.
Wall sits are misery for the sake of misery. So if that's what your after...
Yeah, exactly. How do you progress wall sits? I mean, other than timing them until you collapse of boredom and muscle cramps. What you need is a creative, attention-getting way to increase the ineffectiveness of wall sits, piling on the misery with...even more lack of benefit.
This? No. Oh - no.
|When the lever arm is zero, torque is zero, no matter how large the force.|
THIS is precisely why you should have actually learned your simple Newtonian physics instead of whining around and questioning why exercise science and athletic training majors have to take basic science courses. This is why you should always keep an eye out for applying those basic trigonometric functions and free body diagrams.
[Incidentally, it's also why a good trainer or PT is worth something.]
You can stack the weight of an entire hippo on someones thighs. I don't care if you have the Cat In The Hat himself come and balance on the person with a book on a ball with a fish and a rake. It's all the same to the wall sitter (well, until their patella dislocates or tibia splinters)
Instead, try some goblet squats or step-ups, side lunges or even burpees or pistol squats, suitcase lifts, jumping jacks, somersaults or pirouettes, or, or...
Trainer, coach, teacher, wellness coordinator, great uncle Jimmy... Please. You can do better than wall sits.