the central premise of LSJL is that mechanical pressure can stimulate the epiphyseal growth plate to induce longitudinal bone growth. this fails at the most basic level of human physiology that is the ontogenetic fate of the physis
The Irreversibility of Fusion: the growth plate is not a static structure that remains alive like wtf, it is a transient organ that undergoes programmed raping. research utilizing synchrotron X ray computed microtomography shows that bridging occurs where bone spicules traverse the growth plate physically separating the epiphysis from the metaphysis
even if we ignore the fact that the growth plate is fused the proponents of LSJL misunderstand the fundamental relationship bw mechanical loading and chondrocyte proliferation
Chondrocyte Inhibition: Controlled laboratory studies have shown that compressive loading suppresses longitudinal bone growth. research on rat ulnas
showed that dynamic axial loading resulted in dose dependent growth suppression nd high magnitude loads caused complete cessation of growth and histomorphological damage and disruption of capillary invasion
The Hemiepiphysiodesis Model: ortho surgery uses mechanical compression to stop growth. procedures like hemiepiphysiodesis apply mechanical stress across the growth plate specifically to create angular deformities by fucking growth on one side. studies confirm that mechanical staples induce ER stress and apoptosis and autophagy in chondrocytes. if mechanical pressure was a growth stimulant these surgical procedures would lengthen limbs but instead they rape it
proponents of LSJL often say bs like "microfractures" or "cartilage expansion" as mechanisms for height gain. but the actual histological outcomes of high force joint loading are pathological and not anabolic
The Response to High Load: When the 17N load was applied in the rat model the researchers observed traumatic changes such as cracks in the growth plate (iirc).
The "Catch Up" Fallacy: some LSJL idiots point to "rebound growth" after the removal of staples in hemiepiphysiodesis as proof that pressure stimulates growth. the "catch up" growth observed after removing a mechanical staple is simply the release of inhibition and not new growth stimulation
There is a lot more, but its pointless.
