Explore chapters and articles related to this topic
Measuring and assessing growth
Published in Judy More, Infant, Child and Adolescent Nutrition, 2021
Growth is the product of many biological and environmental interactions spanning numerous cell and tissue types acting during pre- and post-natal development. Chondrogenesis, which is the biological process that drives height gain, occurs in the growth plates which are found near the ends of the bones. More than 100 genes are involved, hence the tendency for children’s growth patterns to relate to their parent’s stature. The on and off switches for the 88 growth genes acting on the chondrocytes in the growth plates are unknown. Bone growth drives muscle growth.
In Vivo Models of Smooth Muscle Growth
Published in Alastair G. Stewart, AIRWAY WALL REMODELLING in ASTHMA, 2020
Various insults to the airways have the potential to induce airway smooth muscle growth. It is not certain to what extent the mechanisms underlying smooth muscle growth are common among the various exogenous stimuli that have been documented to effect growth. A feature in common to most of these stimuli is airway inflammation. The pattern of inflammation has not been adequately compared among the various models to allow any speculation concerning possible responsible cells. Changes in the airway epithelium also are common to most of the models, but the changes are more striking in animals exposed to hyperoxia and sulphur dioxide, whereas allergen-challenged animals have light microscopically normal epithelium. Sulphur dioxide does not affect hyperresponsiveness, however. Even in allergen-challenged animals the epithelium shows signs of response to the exposure, raising the importance of phenotypic changes in the epithelium in evoking changes in the underlying muscle. There is much work to be done to elucidate the precise cellular and molecular mechanisms that cause the airway changes. There is the exciting prospect that careful evaluation of the processes that lead to airway remodelling in vivo may lead to new therapies designed at preventing, rather than palliating, airway disease.
Micronutrient Supplementation and Ergogenesis — Amino Acids
Published in Luke Bucci, Nutrients as Ergogenic Aids for Sports and Exercise, 2020
Typical or usual dietary consumption of glycine, a dispensable amino acid, is 3 to 5 g,754 while 13 to 17 g daily are synthesized by the body.755 Obviously, in order to influence body handling of glycine, large amounts (over several grams at once) must be taken; 30 g of p.o. glycine elevate serum glycine levels fourfold and also increase growth hormone levels to ten times over baseline 2 h after ingestion.754 This amount of glycine was well tolerated. Oral administration of 6.75 g glycine to 19 subjects increased growth hormone significantly for 3 h, peaking at 3 to 4 times baseline at 2 h.756 Likewise, i.v. infusion of 4, 8, or 12 g of glycine led to increases in serum growth hormone.757 Increased growth hormone may be one normal physiological mechanism that accelerates muscle growth after exercise due to its anabolic action. Thus, the results of Chaikelis, which showed an increase in muscle strength after glycine,749 may have been due to increased levels of growth hormone affecting a whole-body resistance training program, a situation not examined in the other reported studies on glycine and physical performance.745,750–753
Early clinical and pre-clinical therapy development in Nemaline myopathy
Published in Expert Opinion on Therapeutic Targets, 2022
Gemma Fisher, Laurane Mackels, Theodora Markati, Anna Sarkozy, Julien Ochala, Heinz Jungbluth, Sithara Ramdas, Laurent Servais
Another consideration is the protein levels needed to maintain a healthy neuromuscular phenotype: A nebulin knockout mouse model demonstrated that nebulin levels declined rapidly in the first weeks of life. Compared to controls, the average knockout nebulin levels at 3 weeks of age were reduced to 48%, to 4.8% at 5 weeks and to 2.2% at 6 months[137]. In the nebulin mouse model described earlier, muscle weight assessments during growth revealed that all muscles were of lower mass than that of control muscle initially. However, from 15 to 25 weeks of age most had increased from baseline, and some muscles such as diaphragm were of equivalent mass to that of controls and soleus was even slightly heavier, implying hypertrophy [138]. Although there was no data to indicate how the hypertrophied soleus muscle performed in terms of force generation and contractility, the observations on muscle hypertrophy may still be useful in the context of therapies aimed at increasing muscle growth such as anti-myostatin agents, IGF-1 or upregulation of IGF-1 in muscle.
The size and echogenicity of the tibialis anterior muscle is preserved in both limbs in young children with unilateral spastic cerebral palsy
Published in Disability and Rehabilitation, 2022
Steven J. Obst, Reuben Bickell, Kaysie Florance, Roslyn N. Boyd, Felicity Read, Lee Barber
Absolute volume of the TA and MG muscle was significantly related to age in all groups (Table 3, Figure 3). There was a significant age by group interaction for absolute MG volume (F54,2=4.023, p = 0.024) and normalised TA volume (F54,2=5.00, p = 0.01), but not normalised MG volume (F54,2=0.068, p = 0.94) or absolute TA volume (F54,2=1.088, p = 0.344). Group differences in muscle growth rates are reported in Table 3. The absolute MG muscle growth rate of TD group was significantly higher than the more-involved limb and less-involved limb of the USCP group. The normalised TA muscle growth rate of the TD group was significantly less than the more-involved and less-involved limbs of the USCP group.
Spirulina platensis Provides a Small Advantage in Vertical Jump and Sprint Performance But Does Not Improve Elite Rugby Players’ Body Composition
Published in Journal of Dietary Supplements, 2021
Mehdi Chaouachi, Sandrine Gautier, Yoann Carnot, Nicolas Bideau, Pierrick Guillemot, Yann Moison, Tom Collin, Sophie Vincent, Carole Groussard
Intense training has been shown to decrease the availability of essential amino acids, which may slow the rate of tissue repair and growth (Kreider 1999). Athletes need to ingest enough high-quality protein in their diet to maintain essential amino acid availability during training and competition (Kerksick et al. 2006) and to generate a greater stimulus for muscle growth and enhanced recovery, potentially resulting in greater strength gains (Ratamess et al. 2003; Kraemer and Spiering 2006). The supposed effects of Spirulina on muscle development are based on its high protein content, especially in essential amino acids such as leucine, valine, and isoleucine. For these reasons, athletes use Spirulina to improve body composition (especially LBM) and physical performance.