I am a maven in the height increase niche who runs a website about growing taller. I have a done a lot of research and studied typical height increase methods like IGF-1 and testosterone. Every way of growing taller leads back to one key entity the mesenchymal stem cells.
Mesenchymal stem cells are present in your red bone marrow in the trabecular bone. It is not however present in the yellow bone marrow which occurs along the shaft of the diaphysis of the long bones. It is present in short, flat, and irregular bones. It is also present in the epiphyseal ends of long bones.
You can grow taller by increasing stem cell proliferation and differentiation in your short, flat, and irregular bones. You grow taller by increasing osteoblastic activity. How you gain height in your spine for instance is either by an increase in periosteal width or by deposition of cortical bone beneath the periosteal layer which expands the bone in width(and in non-long bones: height). You can encourage proliferation of stem cells by loading the stem cells or by chemical methods such as lithium or IGF-1. You want the mesenchymal stem cells to differentiate into osteoblasts which then deposit new bone beneath the periosteum. Certain genetic markers encourage that to happen and load can increase the levels of those genetic markers which causes your MSCs to turn into osteoblasts.
For long bones, you want the MSCs to head into the hyaline cartilage growth plate line and differentiate into chondrocytes which basically re-opens the growth plates(they never technically close). No scientist has tried to inject MSCs into the hyaline cartilage growth plate line. What an obvious mistake! Like with short bones you want genetic markers to be there that encourage your MSCs to differentiate into chondrocytes. Loading your Articular Cartilage can increase these genetic markers.
Mesenchymal stem cells are the key to growing taller.