When I perform LSJL on a synovial joint of a limb I do feel an increase in height in that area and that is more than I usual feel due to changes in body heat.
Unilateral Heat Acelerates Bone Elongation and Lengthens Extremities of Growing Mice
“warm ambient temperature increases bone blood supply and bone length in young mice ”
“Local heat could be an alternative to surgery and a supplement to systemic bone -lengthening drugs to noninvasively achieve limb length equalization.”
“3-week old female C57BL/6 mice (N=20 total) were treated once daily to a 40-minute unilateral heating regimen for 14 days post-weaning”
“5-week old mice (N=14) were euthanized for tissue harvest 1 day after the last heat-treatment. OTC was visualized in unfixed proximal tibial slab sections on a fluorescence stereoscope.
Growth rate was estimated from digital images following published methods. 12-week old mice were euthanized 49 days post-heating to evaluate persistent limb length differences at skeletal maturity. Cartilaginous ears were harvested to document a treatment effect, since ear size changes with ambient temperature”
“Skin temperatures of heat-treated limbs and ears averaged 40C as measured by infrared thermometry during the heat treatments. Temperatures of the non-treated side averaged 30C during treatments. Core temperature and respiration were 36C and 60 breaths/min, respectively, under anesthesia. Tibial elongation rate was >12% greater on the heat-treated side of 5-week old mice. The average growth acceleration was nearly 15 µm/day”<-Growth rate does not always mean an increase in adult height forever.
“Ear area and hindfoot length on the heat-treated side were increased 8.8% and 3.5%, respectively, compared to the non-treated contralateral side at 5-weeks. Femoral and tibial lengths were increased 1.3% and 1.5%, respectively. To test whether left-right differences were evident at skeletal maturity, mice were examined 49 days after the last treatment at 12-weeks age. Importantly, ear area and tibial length were still significantly increased on the heat-treated side of adults”<-in this case it looks like like heat had an impact on height at skeletal maturity.
“unilateral exposure of 40C heat for only 40 min/day increased ear area and hindlimb length on the heat-treated side of young mice.”
Another heat study:
Temperature, heat shock proteins and growth regulation of the bone tissue
Ambient heat modulates the elongation of bones in mammals, and the mechanism of such a plasticity has not been studied completely. The influence of heat on growth and development of bone depends on its values. Five zones of temperature influence on the bone tissue with different biological effects have been distinguished : a) under-threshold thermal zone < 36.6 ºС, insufficient amount of heat is a limiting factor for osteogenesis; b) normal temperature zone 36.6‒37.5 ºС, the processes of breakdown and development of bone in this temperature range is balanced; b) zone of mild thermal shock 39‒41 ºС, the processes of functioning of osteoblasts, osteocytes and formation of the bone tissue intensify; d) the zone of sublethal thermal shock > 42 ºС, growth of bone slows; e) zone of non-critical shock > 50 ºС, bone tissue cells die. We propose a model of the mechanism of influence of heat shock on bone growth. Mild heat shock is a type of stress to which membrane enzymes adenylyl cyclase and cAMP-protein kinase react. Protein kinase A phosphorylates the gene factors of thermal shock proteins, stress proteins and enzymes of energy-generating processes – glycolysis and lipolysis. Heat shock protein HSP70 activates alkaline phosphatase and promotes the process of mineralization of the bone tissue. In the cells, there is intensification in syntheses of insulin-like growth factor-I, factors of mitogenic action, signals of intensification of blood circulation (NO) and synthesis of somatotropin. The affinity between insulin-like growth factor I and its acid-labile subunit decreases, leading to increased free and active insulin-like growth factor I. Against the background of acceleration of the capillarization process, energy generation and the level of stimulators of growth of bone tissue, mitotic and functional activities of producer cells of the bone – osteoblasts and osteocytes – activate. The generally known Allen’s rule has been developed and expanded: “Warm-blooded animals of different species have longer distal body parts (tails) if after birth the young have developed in the conditions of higher temperature”. The indicated tendency is realized through increased biosynthesis of heat shock proteins and other stimulators of growth processes in the bone tissue.”
“Heat and prolonged physical loads promote bone elongation. These factors contribute to increase in the delivery of soluble substances needed for growth of the epiphysial plate”
“cold increased the apoptosis of osteocytes and decreased the length of the canals.”
“exercises alleviated the effect of low temperatures on the process of elongation of the limbs after 11 days of physical load. Regardless of the temperature, all runner mice had elongated limbs, and individuals that had performed no exercises had shorter limbs.”<-so both exercise and temperature could both be different ways of delivering nutrients to growth plates.
Even one session of heating for ~ 2 hours may increase the activity of protein kinase and the process of phosphorylation. Heat influence induces HSP expression. They stabilize proteins that strengthen the transmission of the signals of nitrogen oxide (NO), decrease oxidative stress and inflammation of the vessels and improve their function”
“Vessel network is of essential value for transportation of regulators that support processes of endochondral ossification. Bone has a dense capillary network, and the signal molecules that participate in its growth must overcome the cartilage. The cartilage is included in the epiphyseal plate, but it has no penetrating blood supply”
“The cartilage has no blood vessels and its nutrition is performed by diffusion of substances. The semi penetrable “barrier at the border of vessel -cartilage surface” obstructs the molecular transport. To study the peculiarities of overcoming this obstacle, a model of heating the hind legs was used for manipulating the blood circulation in bones in 5-week-old female mice. In the experiment, dextrans were used weighing 10, 40 and 70 kDa, which are close in size to physiological regulators. Increase in the temperature in hind legs from 22 to 34 °C led to increase in vascular access of the abovementioned molecules.”