itsoverformr
#1 Hltn
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People often think shoulder width is just set by your genes and thats it, nothing you can do about it. But I read this stuff and it turns out the clavicle, which basically decides that width, keeps growing way longer than you might expect. Its the last bone to finish up, with the growth plate on the inside not closing until around 23 to 25 years old. So there is this window, longer than most realize, where maybe you can influence things a bit.
Earlier studies got it wrong because they looked at groups of people at different times, not tracking the same folks. Real growth happens after 18, with the clavicle remodeling more than other bones since its plates close late. Bone adapts to stress, right, like Wolffs Law says it grows and changes with mechanical loading. In teens, bones are super responsive to that kind of thing, especially cyclic exercise that builds strength and architecture.
One study on adolescents showed how loading affects bone during fast growth periods. And there was this genomic thing on cartilage in growth plates, where even short bursts of mechanical stress, like 30 seconds, kick off pathways for bone growth. It changes gene expression directly, which is pretty cool evidence. During puberty, osteoblasts on the bone surface get more active, adding width through appositional growth.
Growth hormone drives a lot of this, along with IGF-1. GH hits the growth plate, stimulates cells there to produce more IGF-1 locally, which expands chondrocytes and lengthens bones. For the clavicle specifically, high IGF-1 helps recruit cells for periosteal growth, boosting osteoblast activity and widening the bone. To max that naturally, deep sleep is huge for GH release, its the biggest factor. Then high intensity workouts, fasting to keep insulin low, plenty of protein, and stuff like zinc and magnesium that people often lack.
Estrogen closes those growth plates in everyone. It comes from testosterone via aromatase enzyme. There are trials with letrozole that block estrogen and delay maturation, leading to taller adults if used in growing kids. Guys with aromatase deficiency end up tall because plates stay open longer, showing estrogen is key for fusion. But inhibitors are no joke, they mess with density, fertility, lipids, all that. Just info, not advice.
One study on adolescents showed how loading affects bone during fast growth periods. And there was this genomic thing on cartilage in growth plates, where even short bursts of mechanical stress, like 30 seconds, kick off pathways for bone growth. It changes gene expression directly, which is pretty cool evidence. During puberty, osteoblasts on the bone surface get more active, adding width through appositional growth.
Growth hormone drives a lot of this, along with IGF-1. GH hits the growth plate, stimulates cells there to produce more IGF-1 locally, which expands chondrocytes and lengthens bones. For the clavicle specifically, high IGF-1 helps recruit cells for periosteal growth, boosting osteoblast activity and widening the bone. To max that naturally, deep sleep is huge for GH release, its the biggest factor. Then high intensity workouts, fasting to keep insulin low, plenty of protein, and stuff like zinc and magnesium that people often lack.
Estrogen closes those growth plates in everyone. It comes from testosterone via aromatase enzyme. There are trials with letrozole that block estrogen and delay maturation, leading to taller adults if used in growing kids. Guys with aromatase deficiency end up tall because plates stay open longer, showing estrogen is key for fusion. But inhibitors are no joke, they mess with density, fertility, lipids, all that. Just info, not advice.
For practical stuff in your growth years, dead hangs every day pull on the shoulder area. Overhead presses remodel the clavicle along its length. Lateral raises target the side plane directly. Swimming gives tons of repetitive loading on shoulders laterally. Optimize sleep for GH peaks, and get enough protein, zinc, magnesium, calcium, vitamin D for mineralization. 8iu of gh every day for 7-12 months and use a aromatase inhibitor everyday to keep growth plates open
The genetic limit on clavicle length is real, you cant go beyond it. After 23 to 25, once plates close, length stays put, no real change. But building muscle and fixing posture can make shoulders look wider anyway, and thats something not to overlook. It seems like that part gets missed a lot.
1. Clavicle continues to grow during adolescence and early adulthood
pmc.ncbi.nlm.nih.gov
2. Substantial clavicle growth and remodeling after age 18
www.sportsmed.org
3. Cyclic loading during adolescence improves bone microstructure and strength
pmc.ncbi.nlm.nih.gov
4. Genomic effects of mechanical loading on human growth plate cartilage
pmc.ncbi.nlm.nih.gov
5. Role of periosteum in bone formation during adolescence
pmc.ncbi.nlm.nih.gov
6. GH and IGF-1 axis in skeletal growth and periosteal bone apposition
pubmed.ncbi.nlm.nih.gov
7. Growth hormone mediates pubertal skeletal development
pmc.ncbi.nlm.nih.gov
8. Aromatase inhibitor letrozole delays bone maturation RCT
pubmed.ncbi.nlm.nih.gov
9. Novel treatment of short stature with aromatase inhibitors
pubmed.ncbi.nlm.nih.gov
10. Aromatase inhibitors for short stature in male adolescents
pmc.ncbi.nlm.nih.gov
11. Growth plate closure and therapeutic interventions review
www.e-cep.org
The Clavicle Continues to Grow During Adolescence and Early Adulthood - PMC
As more adults undergo surgical fixation of clavicle fractures with improved outcomes, interest is renewed in managing clavicle fractures in adolescents. The medial clavicular physis does not fuse until 23 to 25 years of age, but studies report ...
pmc.ncbi.nlm.nih.gov
how long to heal clavicle fracture | Sports Medicine News
Explore sports medicine treatment of clavicle fractures in youth athletes plus how to manage return to play protocols.
www.sportsmed.org
Isolated Cyclic Loading During Adolescence Improves Tibial Bone Microstructure and Strength at Adulthood - PMC
Bone is a unique living tissue, which responds to the mechanical stimuli regularly imposed on it. Adolescence facilitates a favorable condition for the skeleton that enables the exercise to positively influence bone architecture and overall ...
pmc.ncbi.nlm.nih.gov
Genomic Effects of Biomechanical Loading in Adolescent Human Growth Plate Cartilage: A Pilot Study - PMC
The genomic effects of biomechanical loading on human growth plate cartilage are unknown so far. To address this, we used rare human growth plate biopsies obtained from children undergoing epiphysiodesis and exposed them to precisely controlled ...
pmc.ncbi.nlm.nih.gov
The Role of the Periosteum in Bone Formation From Adolescence to Old Age - PMC
Bone formation is a complex process involving the coordinated activity of many different cell types, including osteoblasts and osteocytes. The periosteum is a dense membrane of connective tissue that covers the outer surface of bones and is ...
pmc.ncbi.nlm.nih.gov
Regulation of skeletal growth and mineral acquisition by the GH/IGF-1 axis: Lessons from mouse models - PubMed
The growth hormone (GH) and its downstream mediator, the insulin-like growth factor-1 (IGF-1), construct a pleotropic axis affecting growth, metabolism, and organ function. Serum levels of GH/IGF-1 rise during pubertal growth and associate with peak bone acquisition, while during aging their...
pubmed.ncbi.nlm.nih.gov
Growth Hormone Mediates Pubertal Skeletal Development Independent of Hepatic IGF-1 Production - PMC
Deficiencies in either growth hormone (GH) or insulin-like growth factor 1 (IGF-1) are associated with reductions in bone size during growth in humans and animal models. Liver-specific IGF-1-deficient (LID) mice, which have 75% reductions in serum ...
pmc.ncbi.nlm.nih.gov
A specific aromatase inhibitor and potential increase in adult height in boys with delayed puberty: a randomised controlled trial - PubMed
Our findings suggest that if oestrogen action is inhibited in growing adolescents, adult height will increase. This finding provides a rationale for studies that aim to delay bone maturation in several growth disorders.
pubmed.ncbi.nlm.nih.gov
Novel treatment of short stature with aromatase inhibitors - PubMed
Estrogens have an essential role in the regulation of bone maturation and importantly in the closure of growth plates in both sexes. This prospective, randomized, placebo-controlled study was undertaken to evaluate whether suppression of estrogen synthesis in pubertal boys delays bone maturation...
pubmed.ncbi.nlm.nih.gov
Aromatase inhibitors for short stature in male children and adolescents - PMC
As a result of the essential role of oestrogens in epiphyseal closure, aromatase inhibitors have been trialled as an intervention to improve height outcomes in male children and adolescents by inhibiting the conversion of testosterone to oestradiol. ...
pmc.ncbi.nlm.nih.gov
