Paul
4.8K posts


Golden boys are everywhere 🤩
Tesla CyberCabs are absolutely stealing the show in downtown Austin ✨🤩
@Tesla @Tesla_AI


📐_Cyber_Owl_🦉@RimaSukhadia
Wow! 🤯 How smoothly Golden Tesla Cybercab pulled over for the emergency vehicle on the other side I could barely hear the siren with loud music in my MYP Our future is safe and golden ✨ @robotaxi @Tesla_AI @Tesla @elonmusk
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@DeanTTraining My point was a very specific one. You said the muscle had the most leverage at the bottom of the rep.
That's not true.
That's it.
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@Paul_MechEng Serious question:
Are you familiar with the principle of neuromechanical matching?
(Which is not bulletproof by the way but does appear to have quite a bit of merit)
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A lot of people don’t know why the build of the VERTICAL Hammer Strength Chest Press Machines isn’t ideal for the Pecs
So….allow me to explain it as simply as possible with a few photos:
Red circle = axis of rotation
Blue line = gravity
Purple line = the machine’s arm that’s being moved through space
The resistance is highest when the purple arm is most parallel to the ground because that’s when it’s most perpendicular to gravity creating the largest moment arm
As the arm becomes more vertical, the moment arm shrinks and the movement gets easier
The Pecs have best leverage to move the load in the bottom of the movement when stretched so you would ideally want it to be hardest there and then fall off toward the top where the Triceps have more leverage to move the weight through space
Thus, the inherent build of these machines is legit the OPPOSITE of what you’d want for Pecs


Miscellaneous Ramblings@MRinEng
I've seen info about this quite a few times and still don't get it so @grok explain this like I am 10 years old, please
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You said "leverage" not force production.
There is an interplay between how much force a muscle can produce based on its length and the amount of force it needs to produce to overcome the moment caused by the mass you're lifting.
Even if the amount of force a muscle can produce increases as it stretches, it's a moot point if the amount of force required increases at a faster rate.
Crazy if you think a press is easier at the bottom.
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@Paul_MechEng Muscle force production is based on sarcomere length
Every muscle group has its own length-tension relationship as a result
Again, this is completely independent of the external physics at play
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Yes, but there are to moment arms at play here. The machine moment arm and the skeletal moment arm. The mechanical advantage of the skeletal moment arm decreases the closer to the bottom of the rep you get.
You can literally feel it when you press/squat. The squat literally has a name for it: "the hole"
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@Paul_MechEng Again, the claim that pecs have their best leverage to produce force in the lengthened position is based on the length-tension relationship of the muscle group
Strength curve ≠ resistance profile
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@Paul_MechEng You’re confusing physics with length-tension relationship
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Artemis Mission Route in 3D
- This animation visualizes the Artemis mission trajectory in a dynamic 3D perspective, showing how the spacecraft travels through the Earth–Moon system while all celestial bodies are in motion. Instead of a static path, the Sun, Earth, and Moon move simultaneously, revealing the true complexity of orbital mechanics. The result highlights how the Artemis route is not a simple curve, but a constantly shifting trajectory shaped by gravity and motion. This view provides a clearer understanding of how modern space missions navigate through space in real time. Right now, Artemis is on its return path to Earth and is expected to arrive back soon as it completes its mission. The sizes and distances of the Sun, Earth, and Moon are not to scale and are adjusted for visual purposes.
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May be a different muscle group, but I wouldn't say that has anything to do with it.
You said that the pecs have the best leverage at the bottom of the rep, that's just wrong.. it's literally the opposite. The best leverage is at the top. At the bottom when pec is in full extension the lever arm of the humerus is it's greatest, meaning that the pec will have to produce more force in that position than at the top. That's why you don't see people half repping at the bottom, always at the top.
Same mechanics for the squat, the further you descend, the greater force the muscle has to produce, hence why pendulum squats are good as they decrease the lever arm at the bottom.
Again, you ain't seeing anyone half repping a squat at the bottom. Wonder why.
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@Paul_MechEng The physics are the same
The muscle group being trained isn’t
Pendulums shine mostly because they create a very pain free squat experience as they’re very forgiving on the connective tissue
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Paul 리트윗함

@aus877 @zachary135791 Also has been shown to boost test by precisely 137.2%
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@zachary135791 It has been clinically proven that making this face while doing it increases effectiveness by 75%
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