Exercise and growth hormone: Does one affect the other?

Roemmich, James N.; Rogol, Alan D.

doi:10.1016/s0022-3476(97)70017-9

Cited by 29 publications

(10 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This is in agreement with other studies which have shown that training regimens may increase type I muscle mass, but not type II, in old rats (28,29), and increase the mitotic activity of satellite cells (30). Exercise may stimulate release of growth hormone (31,32). Life-long physical training of rats resulted in increased concentration of the basement membrane collagens of skeletal muscles and preservation of muscle ®ber type I (33).…”

Section: Discussionsupporting

confidence: 92%

Growth hormone and mild exercise in combination increases markedly muscle mass and tetanic tension in old rats

Andersen¹,

Andreassen²,

Ørskov³

et al. 2000

European Journal of Endocrinology

View full text Add to dashboard Cite

Objective: A decline of skeletal muscle mass and strength is seen with aging and immobilization. Growth hormone (GH) has been shown to increase muscle mass. In the present study the effects of a combination of mild exercise and GH on skeletal musculature tetanic tension, dry defatted weight (DDW), volume, water, fat and collagen concentrations were investigated in old rats. Design: Recombinant human GH (2.7 mg/kg per day) was injected subcutaneously for 73 days in 21-month-old female rats. Exercised rats ran on a treadmill, 8 m/min for 1 h/day. The in vivo maximal tetanic tension of the calf musculature (m. soleus, m. plantaris, m. gastrocnemius together) was analysed in anaesthetized rats by stimulating the ischiadic nerve. Results: The maximal tetanic tension was increased by 23% in GH-injected compared to saline-injected rats. Mild exercise GH in combination resulted in a further 18% increase in maximal tetanic tension. The mild exercise by itself did not in¯uence the maximal tetanic tension signi®cantly when compared with saline injected rats. The GH administration and/or mild exercise did not change skeletal muscle endurance, measured as tetanic tension during 30 s of stimulation. Serum IGF-I concentration was increased twofold in GH-injected rats. Conclusion: The increased muscle mass induced by GH mild exercise was associated with a corresponding increase in maximal tetanic tension. Combination of GH mild exercise resulted in a substantial further increase of muscle mass and maximal tension compared with GH injections alone in these old rats.

show abstract

Section: Discussionsupporting

confidence: 92%

Growth hormone and mild exercise in combination increases markedly muscle mass and tetanic tension in old rats

Andersen¹,

Andreassen²,

Ørskov³

et al. 2000

European Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…With the growing understanding that GH molecular weight variants have diverse and very specific physiological functions (Baumann and Stolar 1986, 1991a, 1991bLewis et al 2000), an understanding of the dynamics of aggregated GH is crucial to ascertain a complete understanding of the physiological processes governed by GH (i.e., macronutrient metabolism, linear bone growth, insulin-like growth factors). Acute exercise represents a provocative stimulus to study such hormone dynamics (Felsing et al 1992;Roemmich and Rogol 1997). The results of the present investigation indicate that aggregated GH in the form of disulfide-linked dimers, and possibly higher molecular weight complexes, exist in the human circulation in response to acute high-intensity exercise.…”

Section: Discussionmentioning

confidence: 60%

Responses of growth hormone aggregates to different intermittent exercise intensities

et al. 2003

View full text Add to dashboard Cite

The purpose of this study was to determine the impact of high-intensity intermittent exercise on the presence of circulating growth hormone (GH) aggregates measured using two different assay techniques. Six male subjects with endurance training background participated in this study under both exercise and no-exercise control conditions. After resting blood sampling, subjects completed an intermittent treadmill exercise protocol at four speeds predicted to elicit a specific VO(2):60% VO(2max) for 10 min, 75% for 10 min, 90% for 5 min, and 100% for 2 min. After each exercise intensity was completed treadmill speed was reduced to a walk (3.5-4 min) for blood sampling. Sampling continued every 15 min for 1 h into recovery. All samples were then measured for GH concentrations using Nichols immunoradiometric assay (IRMA) and Diagnostic Systems Laboratory's immunofunctional assay (IFA). A second set of samples was chemically reduced using reduced glutathione (GSH; 10 mM for 18 h at room temperature) to break disulfide bonds between possible oligomeric GH complexes, and subsequently assayed using the same GH assays. With the IRMA, GH was significantly elevated ( P<0.05) after the 75% workload and remained elevated through 30 min post-exercise. After adding GSH to the sample, the IRMA indicated significant increases in GH as early as the 60% exercise intensity and remained elevated through 45 min into recovery. At 75%, the GSH assay run was significantly higher than the non-GSH assay run. With the IFA, GH was significantly elevated at 60% in the non-GSH condition, whereas the GSH assay run indicated significant elevations at 75%. Both GSH and non-GSH conditions remained elevated through 30 min into recovery. These data indicate that the addition of GSH to serum samples prior to assay via an IRMA may break existing disulfide bonds between aggregated GH molecules, thus altering the apparent assay signal to reveal greater total GH in the sample.

show abstract

“…However, it is generally agreed that the hormonal milieu plays an important role in the anabolic effects of PA. The primary basis for skeletal muscle growth during childhood and adolescence is the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis (11,38), androgens (estrogen and testosterone) and their interaction with GH (39), and insulin (22). Cooper (11) has proposed a conceptual model of the exercise modulation of growth, which includes both central and local components.…”

Section: Discussionmentioning

confidence: 99%

The influence of physical activity on lean mass accrual during adolescence: a longitudinal analysis

Baxter-Jones

Eisenmann²,

Mirwald

et al. 2008

Journal of Applied Physiology

101

View full text Add to dashboard Cite

Baxter-Jones AD, Eisenmann JC, Mirwald RL, Faulkner RA, Bailey DA. The influence of physical activity on lean mass accrual during adolescence: a longitudinal analysis. J Appl Physiol 105: 734-741, 2008. First published May 8, 2008 doi:10.1152/japplphysiol.00869.2007.-During childhood, physical activity is likely the most important modifiable factor for the development of lean mass. However, the effects of normal growth and maturation must be controlled. To distinguish effects of physical activity from normal growth, longitudinal data are required. One hundred nine boys and one hundred thirteen girls, participating in the Saskatchewan Pediatric Bone Mineral Accrual Study, were repeatedly assessed for 6 yr. Age at entry was 8 -15 yr. Stature, body mass, and physical activity were assessed biannually. Body composition was assessed annually by dual-energy X-ray absorptiometry. Physical activity was determined using the physical activity questionnaires for children and adolescence. Biological age was defined as years from age of peak height velocity. Data were analyzed using multilevel random-effects models. In boys, it was found that physical activity had a significant time-dependent effect on lean mass accrual of the total body (484.7 Ϯ 157.1 g), arms (69.6 Ϯ 27.2 g), legs (197.7 Ϯ 60.5 g), and trunk (249.1 Ϯ 91.4 g) (P Ͻ 0.05). Although the physical activity effects were similar in the girls (total body: 306.9 Ϯ 96.6 g, arms: 31.4 Ϯ 15.5 g, legs: 162.9 Ϯ 40.0 g, and trunk: 119.6 Ϯ 58.2 g; P Ͻ 0.05), boys for the same level of activity accrued, depending on the site, between 21 and 120% more absolute lean mass (g). In conclusion, habitual physical activity had a significant independent influence on the growth of lean body mass during adolescence, once biological maturity and stature were controlled. growth and development; exercise; longitudinal studies SEVERAL FACTORS INFLUENCE the normal biological growth and maturation of the child and adolescent. Although genes, nutrients, and hormones are viewed as the chief determinants, the level of habitual physical activity (PA) is thought to be one of several ancillary factors contributing to the growth and maturation of body size and composition (11,51). Recently, concern has been expressed regarding the low levels of habitual PA and associated negative health outcomes among contemporary youth (49).Most of the previous studies examining the influence of PA on body composition of children and adolescents have focused on either adiposity (4) or bone accrual (2), given the concern of obesity and osteoporosis, respectively. In contrast, few studies have considered the influence of PA on lean body mass (LBM) in children and/or adolescents. LBM is often considered a surrogate for skeletal muscle mass, which is an important predictor of several physiological capacities expressed in absolute terms (e.g., maximal oxygen uptake, neuromuscular strength, anaerobic capacity, etc.) (1, 54) and health indicators (e.g., bone mass, insulin resistance, and obesity) (18,56). Previous stud...

show abstract

Exercise and growth hormone: Does one affect the other?

Cited by 29 publications

References 48 publications

Growth hormone and mild exercise in combination increases markedly muscle mass and tetanic tension in old rats

Growth hormone and mild exercise in combination increases markedly muscle mass and tetanic tension in old rats

Responses of growth hormone aggregates to different intermittent exercise intensities

The influence of physical activity on lean mass accrual during adolescence: a longitudinal analysis

Contact Info

Product

Resources

About