GH Is Needed for the Maturation of Muscle Mass and Strength in Adolescents

The postpubertal period and the early years of adulthood may be of importance for continuing tissue maturation of importance in adulthood and aging. An example of this is the peak bone mass. This study has evaluated the importance of GH for lean mass and muscle strength in adolescents and young adults. GH treatment was discontinued in 40 adolescents aged 16–21 yr with GH deficiency of childhood onset. Measurements of isometric and isokinetic knee-extensor and flexor strength, handgrip strength, lean body mass, fat-free mass, and total body nitrogen were performed annually for 2 yr. Two hundred fifty healthy adolescents were randomly selected for prospective measurements of lean mass and handgrip strength between the ages of 17 and 21 yr. In the adolescents with continuing GH deficiency, lean body mass decreased, compared with the patients defined as having sufficient endogenous GH. The isometric strength in knee flexors increased in the sufficient endogenous GH group and was unchanged in the GH deficiency group during the 2 yr off GH treatment (between group, P < 0.05). The mean and peak handgrip strength increased on average by 9–15% in the group with sufficient endogenous GH and was unchanged in those with GH deficiency (P< 0.05). Lean body mass and handgrip strength (both, P < 0.001) increased in both the healthy boys and girls who were followed for 4 yr with a more marked increase in the boys. The mean increase in handgrip between the age of 17 and 21 yr was 7–9%. The increased lean mass and improved muscle performance seen in healthy adolescents did not occur in adolescents with GH deficiency. These findings suggest that GH is of importance for the maturation of lean mass and muscle strength in adolescents and young adults.

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Skeletal Muscle Characteristics and Motor Performance After 2-Year Growth Hormone Treatment in Adults With Prader-Willi Syndrome

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2013-3607 ◽

2014 ◽

Vol 99 (5) ◽

pp. 1816-1824 ◽

Cited By ~ 23

Author(s):

Claudio L. Lafortuna ◽

Alessandro Minocci ◽

Paolo Capodaglio ◽

Luca A. Gondoni ◽

Alessandro Sartorio ◽

...

Keyword(s):

Body Mass ◽

Motor Performance ◽

Gh Deficiency ◽

Handgrip Strength ◽

Peak Torque ◽

Knee Extension ◽

Gh Treatment ◽

Cross Sectional ◽

Walking Tests ◽

Exercise Endurance

Context: In adults with Prader-Willi syndrome (PWS), abnormal body composition with decreased lean body mass and skeletal muscle (SM) volume has been related to altered GH secretion and may possibly contribute to greatly reduced motor capacity. Objective: The scope of the study was to test the hypothesis that GH treatment has favorable effects on SM characteristics and motor performance in adults with PWS. Design, Setting, and Participants: Fifteen obese PWS subjects (nine males and six females; age range, 19–35 y; body mass index, 37.7–59.9 kg/m2) were investigated before and after 12 (GH12) and 24 (GH24) months of GH treatment. Main Outcome Measures: SM cross-sectional area and SM attenuation were determined with computed tomography at the lumbar and midthigh levels. Maximal isometric handgrip strength and isokinetic knee extension peak torque were measured. Motor performance was evaluated with different indoor walking tests, whereas exercise endurance was assessed with a treadmill incremental test to exhaustion. Results: A condition of severe GH deficiency was found in six patients (40%). GH treatment significantly increased lean body mass (GH12, P < .05; GH24, P < .05), reduced percentage of body fat (GH12, P < .05; GH24, P < .05), and augmented SM cross-sectional area and SM attenuation of both lumbar (GH12, P < .01; GH24, P < .001) and thigh muscles (GH24, P < .05). Handgrip strength increased by 7% at GH12 (P < .05) and by 13% at GH24 (P < .001). Peak torque of knee extension extrapolated at zero angular velocity was significantly higher at GH24 (P < .01), and exercise endurance rose by 13% (P < .05) and 17% (P < .05) before exhaustion at GH12 and GH24, respectively, whereas no change was detected with walking tests. No significant difference in the response to GH treatment was detected between patients with and without GH deficiency. Conclusion: Long-term GH treatment in adult PWS patients improves body composition and muscle size and quality and increases muscle strength and exercise tolerance independently from the GH secretory status.

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Retesting Young Adults with Childhood-Onset Growth Hormone (GH) Deficiency with GH-Releasing-Hormone-Plus-Arginine Test1

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.85.10.6858 ◽

2000 ◽

Vol 85 (10) ◽

pp. 3693-3699

Author(s):

G. Aimaretti ◽

C. Baffoni ◽

S. Bellone ◽

L. Di Vito ◽

G. Corneli ◽

...

Keyword(s):

Young Adults ◽

Gh Deficiency ◽

Statistical Significance ◽

Young Patients ◽

Normal Subjects ◽

Childhood Onset ◽

Gh Treatment ◽

Provocative Test ◽

Gh Secretion ◽

The Mean

Within an appropriate clinical context, severe GH deficiency (GHD) in adults has to be defined biochemically by provocative testing of GH secretion. Patients with childhood-onset GHD need retesting in late adolescence or young adulthood to verify whether they have to continue recombinant human GH treatment. GHRH + arginine (GHRH+ARG) is the most reliable alternative to the insulin-induced hypoglycemia test (ITT) as a provocative test for the diagnosis of GHD in adulthood, provided that appropriate cut-off limits are assumed (normal limits, 16.5 μg/L as 3rd and 9.0 μg/L as 1st centile). We studied the GH response to a single GHRH (1 μg/kg iv) + ARG (0.5 g/kg iv) test in 62 young patients who had undergone GH replacement in childhood, based on the following diagnosis: 1) organic hypopituitarism with GHD (oGHD)[ n = 18: 15 male (M), 3 female (F); age, 26.8 ± 2.2 yr; GH peak < 10 μg/L after two classical tests]; 2) idiopathic isolated GHD (iGHD) [n = 23 (15 M, 8 F); age, 23.0 ± 1.5 yr; GH peak < 10 μg/L after two classical tests]; and 3) GH neurosecretory dysfunction (GHNSD) [n = 21 (10 M, 11 F); age, 25.1 ± 1.6 yr; GH peak > 10 μg/L after classical test but mGHc < 3 μg/L]. The GH responses to GHRH+ARG in these groups were also compared with that recorded in a group of age-matched normal subjects (NS) [n = 48 (20 M, 28 F); age, 27.7 ± 0.8 yr]. Insulin-like growth factor I levels in oGHD subjects (61.5 ± 13.7μ g/L) were lower (P < 0.001) than those in iGHD subjects (117.2 ± 13.1 μg/L); the latter were lower than those in GHNSD subjects (210.2 ± 12.9 μg/L), which, in turn, were similar to those in NS (220.9 ± 7.1 μg/L). The mean GH peak after GHRH+ARG in oGHD (2.8 ± 0.8 μg/L) was lower (P < 0.001) than that in iGHD (18.6 ± 4.7μ g/L), which, in turn, was clearly lower (P < 0.001) than that in GHNSD (31.3 ± 1.6 μg/L). The GH response in GHNSD was lower than that in NS (65.9 ± 5.5 μg/L), but this difference did not attain statistical significance. With respect to the 3rd centile limit of GH response in young adults (i.e. 16.5 μg/L), retesting confirmed GHD in all oGHD, in 65.2% of iGHD, and in none of the GHNSD subjects. With respect to the 1st centile limit of GH response (i.e. 9.0 μg/L), retesting demonstrated severe GHD in 94% oGHD and in 52.1% of iGHD. All oGHD and iGHD with GH peak after GHRH+ARG lower than 9 μg/L had also GH peak lower than 3 μg/L after ITT. In the patients in whom GHD was confirmed by retesting, the mean GH peak after GHRH+ARG was higher than that after ITT (3.4 ± 0.5 vs. 1.9 ± 0.4). In conclusion, given appropriate cut-off limits, GHRH+ARG is as reliable as ITT for retesting patients who had undergone GH treatment in childhood. Among these patients, severe GHD in adulthood is generally confirmed in oGHD, is frequent in iGHD, but never occurs in GHNSD.

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Effect of exogenous growth hormone and exercise on lean mass and muscle function in children with burns

Journal of Applied Physiology ◽

10.1152/japplphysiol.00849.2002 ◽

2003 ◽

Vol 94 (6) ◽

pp. 2273-2281 ◽

Cited By ~ 65

Author(s):

Oscar E. Suman ◽

Steve J. Thomas ◽

Judy P. Wilkins ◽

Ronald P. Mlcak ◽

David N. Herndon

Keyword(s):

Growth Hormone ◽

Muscle Strength ◽

Lean Body Mass ◽

Body Mass ◽

Recombinant Human Growth Hormone ◽

Rehabilitation Program ◽

Physical Rehabilitation ◽

Percent Change ◽

Home Based ◽

The Mean

We tested the hypothesis that the administration of recombinant human growth hormone (rHGH) and exercise would increase lean body mass (LBM) and muscle strength in burned children to a greater extent than rHGH or exercise separately. Children, ages 7–17 yr, with >40% body surface area burned, were randomized into groups. One group (GHEX, n = 10) participated in a 12-wk in-hospital physical rehabilitation program supplemented with an exercise program and received 0.05 mg · kg−1· day−1of rHGH. A second exercising group (SALEX, n = 13) received saline. A third group (GH, n = 10) received a similar dose of rHGH as GHEX and participated in a 12-wk, home-based physical rehabilitation program without exercise. The fourth group (Saline, n = 11) received saline and participated in a 12-wk, home-based physical rehabilitation program without exercise. The mean (±SE) percent change in lean body mass after 12 wk was not significantly different between GHEX (9.0 ± 2.1%), SALEX (5.4 ± 1.6%), and GH (5.8 ± 1.8%) groups ( P = 0.33). However, the mean percent change in muscle strength was significantly greater in the GHEX (36.2 ± 5.4%) and SALEX (42.6 ± 10.0%) groups than in the GH (−7.4 ± 4.7%) or Saline (6.7 ± 4.4%) groups ( P = 0.008). In summary, rHGH GHEX, SALEX, and GH alone produced similar improvements in LBM. However, muscle strength was only increased via exercise.

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Prevalence of sarcopenia in kidney transplants and their association with determinant factors of muscle homeostasis

Revista da Associação Médica Brasileira ◽

10.1590/1806-9282.66.9.1235 ◽

2020 ◽

Vol 66 (9) ◽

pp. 1235-1240

Author(s):

Cleodice Alves Martins ◽

Ana Karina Teixeira da Cunha França ◽

Raimunda Sheyla Carneiro Dias ◽

Rayanna Cadilhe de Oliveira Costa ◽

Antônio Pedro Leite Lemos ◽

...

Keyword(s):

Renal Transplant ◽

Muscle Strength ◽

Lean Body Mass ◽

Body Mass ◽

Handgrip Strength ◽

University Hospital ◽

Renal Transplant Recipients ◽

Transplant Recipients ◽

Kidney Transplant Recipients ◽

Muscle Homeostasis

SUMMARY INTRODUCTION: Sarcopenia is characterized by the involuntary loss of lean body mass associated with a progressive reduction of muscle strength. OBJECTIVE: To determine the prevalence of sarcopenia in kidney transplant recipients and its association with the determining factors that control muscle homeostasis. METHODS: We evaluated renal transplant recipients undergoing follow-up at the University Hospital of the Federal University of Maranhão from June 2017 to July 2018 and who met the inclusion criteria. Sarcopenia was defined according to the European criteria. The skeletal muscle mass index was measured by dual-energy radiological absorptiometry; the values <7,26 kg/m2 for men and <5,5 kg/m2 for women were adopted for muscle depletion. For handgrip strength, values of <30 kg for men and <20 kg for women were considered as reduced muscle strength. In both sexes, the cutoff point for walking speed was <0,8 m/s. RESULTS: We evaluated 83 renal transplant recipients with a mean age of 48.8 ± 12,1 years and predominantly males (57,8%). The prevalence of sarcopenia was 19,3%. Among individuals without sarcopenia, 17,9% had a decrease in handgrip strength and 40,3% has altered gait speed. DISCUSSION: Individuals submitted to renal transplant may develop sarcopenia while still young and already present altered muscle function and strength even before the depletion of lean body mass. CONCLUSION: Early diagnosis may allow the prevention of sarcopenia and provide a better quality of life for patients.

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WOMEN’S FEMORAL MASS CONTENT CORRELATES TO MUSCLE STRENGTH INDEPENDENTLY OF LEAN BODY MASS

Revista Brasileira de Medicina do Esporte ◽

10.1590/1517-869220192506208956 ◽

2019 ◽

Vol 25 (6) ◽

pp. 485-489

Author(s):

Luciana Duarte Pimenta ◽

Danilo Alexandre Massini ◽

Daniel Dos Santos ◽

Leandro Oliveira Da Cruz Siqueira ◽

Andrei Sancassani ◽

...

Keyword(s):

Body Composition ◽

Muscle Strength ◽

Lean Body Mass ◽

Muscle Mass ◽

Body Mass ◽

Lean Mass ◽

The Body ◽

Whole Body ◽

Regional Body Composition ◽

Body Lean Mass

ABSTRACT Introduction There is limited consensus regarding the recommendation of the most effective form of exercise for bone integrity, despite the fact that weight training exercise promotes an increase in muscle mass and strength as recurrent responses. However, strength variations in women do not depend on muscle mass development as they do in men, but strength enhancement has shown the potential to alter bone mineral content (BMC) for both sexes. Objective This study analyzed the potential of muscle strength, as well as that of whole-body and regional body composition, to associate femoral BMC in young women. Methods Fifteen female college students (aged 24.9 ± 7.2 years) were assessed for regional and whole-body composition using dual-energy X-ray absorptiometry (DXA). Maximum muscle strength was assessed by the one-repetition maximum (1RM) test in the following exercises: bench press (BP), lat pulldown (LP), knee flexion (KF), knee extension (KE) and 45° leg press (45LP). Linear regression analyzed BMC relationships with regional composition and 1RM values. Dispersion and error measures (R 2 aj and SEE), were tested, defining p ≤0.05. Results Among body composition variables, only total lean body mass was associated with femoral BMC values (R 2 aj = 0.37, SEE = 21.3 g). Regarding strength values, 1RM presented determination potential on femoral BMC in the CE exercise (R 2 aj = 0.46, SEE = 21.3 g). Conclusions Muscle strength aptitude in exercises for femoral regions is relevant to the femoral mineralization status, having associative potential that is similar to and independent of whole-body lean mass. Therefore, training routines to increase muscle strength in the femoral region are recommended. In addition, increasing muscle strength in different parts of the body may augment bone remodeling stimulus, since it can effectively alter total whole-body lean mass. Level of Evidence II; Development of diagnostic criteria in consecutive patients (with universally applied reference ‘‘gold’’ standard).

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Is Subjective Global Assessment a Good Index of Nutrition in Peritoneal Dialysis Patients with Gastrointestinal Symptoms?

Peritoneal Dialysis International ◽

10.1177/089686080902902s15 ◽

2009 ◽

Vol 29 (2_suppl) ◽

pp. 78-82 ◽

Cited By ~ 6

Author(s):

Yanjun Li ◽

Jie Dong ◽

Li Zuo

Keyword(s):

Peritoneal Dialysis ◽

Lean Body Mass ◽

Body Mass ◽

Global Assessment ◽

Handgrip Strength ◽

Subjective Global Assessment ◽

Gi Symptoms ◽

Group 3 ◽

Group 2 ◽

Group 1

Objective We investigated whether patients with gastrointestinal (GI) symptoms were prone to be diagnosed as malnourished by subjective global assessment (SGA) by simultaneously evaluating SGA and other indices of nutrition in a cross-sectional survey of peritoneal dialysis (PD) patients. Patients and Method From June 2006 to June 2007, 214 PD patients were involved in the study. We recorded results of a GI symptoms questionnaire (GSQ) and SGA. Other indices of nutrition included dietary intake, chemistry examination, anthropometry, handgrip strength, and lean body mass measured by creatinine kinetics. Results Mean age of the 214 PD patients enrolled in the study was 60.22 ± 14.02 years, and mean dialysis duration was 60.22 ± 14.02 months. Of the 214 patients, 56 (27.16%) were diagnosed as malnourished by SGA. The mean GSQ scores were 9.37 ± 1.71 (range: 8 – 17). There were 90 patients with GSQ scores of 8 (group 1), 80 patients with scores of 9 or 10 (group 2), 44 patients with scores of 11 or more (group 3). The prevalence of malnutrition diagnosed by SGA was significantly different in the three groups: 15.56% in group 1, 27.5% in group 2, and 45.45% in group 3 ( p = 0.02). However, we observed no difference between the three groups in mid-arm circumference, skinfold thickness (biceps, triceps, subscapular, and suprailiac), daily protein and energy intake, handgrip strength, lean body mass, and serum albumin and prealbumin levels ( p > 0.05). Conclusions Our results showed that the reliability of SGA in PD patients with GI symptoms remains worth exploring. These patients are possibly diagnosed as malnourished by SGA, although many other indices of nutrition are not necessarily bad.

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Endocrine Dysfunction in Prader-Willi Syndrome: A Review with Special Reference to GH

Endocrine Reviews ◽

10.1210/edrv.22.6.0447 ◽

2001 ◽

Vol 22 (6) ◽

pp. 787-799 ◽

Cited By ~ 167

Author(s):

Pia Burman ◽

E. Martin Ritzén ◽

Ann Christin Lindgren

Keyword(s):

Replacement Therapy ◽

Lean Body Mass ◽

Body Mass ◽

Genetic Disorder ◽

Hormone Replacement ◽

Hypogonadotropic Hypogonadism ◽

Endocrine Disorders ◽

Prader Willi Syndrome ◽

Gh Treatment ◽

Pituitary Dysfunction

Abstract Prader-Willi syndrome is a genetic disorder occurring in 1 in 10,000–16,000 live-born infants. In the general population, approximately 60 people in every 1,000,000 are affected. The condition is characterized by short stature, low lean body mass, muscular hypotonia, mental retardation, behavioral abnormalities, dysmorphic features, and excessive appetite with progressive obesity. Furthermore, morbidity and mortality are high, probably as a result of gross obesity. Most patients have reduced GH secretory capacity and hypogonadotropic hypogonadism, suggesting hypothalamic-pituitary dysfunction. Replacement of GH and/or sex hormones may therefore be beneficial in Prader-Willi syndrome, and several clinical trials have now evaluated GH replacement therapy in affected children. Results of GH treatment have been encouraging: improved growth, increased lean body mass, and reduced fat mass. There was also some evidence of improvements in respiratory function and physical activity. The long-term benefits of GH treatment are, however, still to be established. Similarly, the role of sex hormone replacement therapy needs to be clarified as few data exist on its efficacy and potential benefits. In summary, Prader-Willi syndrome is a disabling condition associated with GH deficiency and hypogonadism. More active treatment of these endocrine disorders is likely to benefit affected individuals.

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Handgrip strength and muscle fatigue among footwear industry workers

Fisioterapia em Movimento ◽

10.1590/0103-5150.029.002.ao10 ◽

2016 ◽

Vol 29 (2) ◽

pp. 317-324 ◽

Cited By ~ 2

Author(s):

Lidiane Angélica Cotelez ◽

Maysa Venturoso Gongora Buckeridge Serra ◽

Eliane Ramos ◽

José Eduardo Zaia ◽

Flávia Oliveira Toledo ◽

...

Keyword(s):

Muscle Strength ◽

Muscle Fatigue ◽

Handgrip Strength ◽

Strength Test ◽

Strength Testing ◽

Test Results ◽

Irreversible Damage ◽

Low Correlation ◽

Footwear Industry ◽

The Mean

Abstract Introduction: Muscle fatigue can be defined as a decrease in the performance of the neuromuscular system in generating force. This situation is considered a complex physiological process involving various body systems, in order to avoid irreversible damage or even cell death. Objective: The aim of this study was to measure muscle strength in order to assess the level of fatigue among footwear industry workers, and to determine a possible correlation between muscle strength and the perception of reported fatigue. Materials and Methods: The study included 32 male workers from the footwear industry with a mean age of 34.63 ± 11.98 years. The workers performed the handgrip strength test using a handheld dynamometer, and completed the Bipolar Fatigue Questionnaire. Results: The mean result of strength testing was 23.1 ± 8.3 kgf, and the mean score of the fatigue questionnaire was 2.28 ± 0.93 points. However, a low correlation was observed between the results of the fatigue questionnaire and the strength test results. Conclusion: The grip strength results of the footwear workers were below the values for the general Brazilian population, a fact that may indicate potential muscle fatigue. However, a low correlation with the perception of fatigue was indicated by the questionnaire.

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