Chronic resistance training in women potentiates growth hormone in vivo bioactivity: characterization of molecular mass variants

2006 ◽  
Vol 291 (6) ◽  
pp. E1177-E1187 ◽  
Author(s):  
William J. Kraemer ◽  
Bradley C. Nindl ◽  
James O. Marx ◽  
Lincoln A. Gotshalk ◽  
Jill A. Bush ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Resistance Training ◽  
Resistance Exercise ◽  
Molecular Mass ◽  
Acute Exercise ◽  
Control Group ◽  
Detection Systems ◽  
Molecular Variants ◽  
Exercise Induced

This investigation determined the influence of acute and chronic resistance exercise on responses of growth hormone (GH) molecular variants in women. Seventy-four healthy young women (23 ± 3 yr, 167 ± 7 cm, 63.8 ± 9.3 kg, 26.3 ± 4.0% body fat) performed an acute bout of resistance exercise (6 sets of 10 repetition maximum squat). Blood samples were obtained pre- and postexercise. Resulting plasma was fractionated by molecular mass ( fraction A, >60 kDa; fraction B, 30–60 kDa; and fraction C, <30 kDa) using chromatography. Fractionated and unfractionated (UF) plasma was then assayed for GH using three different detection systems (monoclonal immunoassay, polyclonal immunoassay, and rat tibial line in vivo bioassay). Subjects were then matched and randomly placed into one of four resistance exercise training groups or a control group for 24 wk. All experimental procedures were repeated on completion of the 24-wk resistance training programs. After acute exercise, immunoassays showed consistent increases in UF GH samples and fractions B and C; increases in fraction A using immunoassay were seen only in the monoclonal assay. No consistent changes in bioactive GH were found following acute exercise. Conversely, chronic exercise induced no consistent changes in immunoassayable GH of various molecular masses, whereas, in general, bioassayable GH increased. In summary, although acute exercise increased only immunoactive GH, chronic physical training increased the biological activity of circulating GH molecular variants. Increased bioactive GH was observed across all fractions and training regimens, suggesting that chronic resistance exercise increased a spectrum of GH molecules that may be necessary for the multitude of somatogenic and metabolic actions of GH.

Acute and Chronic Hormonal Responses to Resistance Training Designed to Promote Muscle Hypertrophy

1999 ◽  
Vol 24 (1) ◽  
pp. 96-107 ◽  
Author(s):  
Gary E. Mccall ◽  
William C. Byrnes ◽  
Steven J. Fleck ◽  
Arthur Dickinson ◽  
William J. Kraemer
Keyword(s):  
Growth Hormone ◽  
Resistance Training ◽  
Acute Exercise ◽  
High Volume ◽  
Sex Hormone Binding Globulin ◽  
Control Group ◽  
Type I ◽  
Hormonal Responses ◽  
Serum Hormone ◽  
Exercise Induced

Acute and chronic hormonal responses to resistance training were evaluated in 11 college men who completed 12 weeks (33 sessions) of high volume resistance training. No differences in resting concentrations of growth hormone (GH), insulin-like growth factor-I, testosterone, or sex hormone-binding globulin occurred from pre- and posttraining in the trained vs. nontrained control group. However, cortisol (C) decreased 17% for both groups (p < 0.05). There were no differences in exercise-induced responses between Sessions 10 and 20, with all hormone concentrations increasing (p < 0.05) from pre- at mid- and postexercise session. However, after correction for plasma volume decreases, only C and GH showed differences, with C increased from mid- to postsession (48% 10th: 49% 20th), and GH increased from pre- at mid- and postsession for both sessions 10 (0.16 ± 0.42 pre; 4.77 ± 6.24 mid; 6.26 ± 5.19 post; µg L−1) and 20 (0.33 ± 085 pre; 5.42 ± 9.08 mid; 8.24 ± 7.61 post; µg L−1). Significant correlations (p < 0.05) existed only between absolute mean GH increases from presession and the degree of muscle fiber hypertrophy for type I (r = 0.70 mid, 0.74 post) and type II (r = 0.71 post) fibers. In conclusion, resistance training had no effect on resting serum hormone concentrations, whereas similar acute exercise responses occurred between the 10th and 20th training sessions. Keywords: humans, weight training, growth hormone, IGF-I, testosterone, cortisol

scholarly journals Resistance training reduces the acute exercise-induced increase in muscle protein turnover

1999 ◽  
Vol 276 (1) ◽  
pp. E118-E124 ◽  
Author(s):  
S. M. Phillips ◽  
K. D. Tipton ◽  
A. A. Ferrando ◽  
R. R. Wolfe
Keyword(s):  
Resistance Training ◽  
Resistance Exercise ◽  
Acute Exercise ◽  
Muscle Protein ◽  
Exercise Bout ◽  
Muscle Contractions ◽  
Breakdown Rates ◽  
Single Bout ◽  
Fractional Synthesis ◽  
Exercise Induced

We examined the effect of resistance training on the response of mixed muscle protein fractional synthesis (FSR) and breakdown rates (FBR) by use of primed constant infusions of [2H5]phenylalanine and [15N]phenylalanine, respectively, to an isolated bout of pleiometric resistance exercise. Trained subjects, who were performing regular resistance exercise (trained, T; n = 6), were compared with sedentary, untrained controls (untrained, UT; n = 6). The exercise test consisted of 10 sets (8 repetitions per set) of single-leg knee flexion (i.e., pleiometric muscle contraction during lowering) at 120% of the subjects’ predetermined single-leg 1 repetition maximum. Subjects exercised one leg while their contralateral leg acted as a nonexercised (resting) control. Exercise resulted in an increase, above resting, in mixed muscle FSR in both groups (UT: rest, 0.036 ± 0.002; exercise, 0.0802 ± 0.01; T: rest, 0.045 ± 0.004; exercise, 0.067 ± 0.01; all values in %/h; P< 0.01). In addition, exercise resulted in an increase in mixed muscle FBR of 37 ± 5% (rest, 0.076 ± 0.005; exercise, 0.105 ± 0.01; all values in %/h; P < 0.01) in the UT group but did not significantly affect FBR in the T group. The resulting muscle net balance (FSR − FBR) was negative throughout the protocol ( P < 0.05) but was increased in the exercised leg in both groups ( P < 0.05). We conclude that pleiometric muscle contractions induce an increase in mixed muscle protein synthetic rate within 4 h of completion of an exercise bout but that resistance training attenuates this increase. A single bout of pleiometric muscle contractions also increased the FBR of mixed muscle protein in UT but not in T subjects.

Does β3-adrenoreceptor blockade attenuate acute exercise-induced reductions in leptin mRNA?

1999 ◽  
Vol 87 (5) ◽  
pp. 1678-1683 ◽  
Author(s):  
S. Brooke Bramlett ◽  
Jun Zhou ◽  
Ruth B. S. Harris ◽  
Stephen L. Hendry ◽  
Trudy L. Witt ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Acute Exercise ◽  
Liver Glycogen ◽  
Treadmill Running ◽  
Control Group ◽  
Mrna Levels ◽  
Sprague Dawley ◽  
Receptor Stimulation ◽  
Exercise Induced

We investigated the effect of a single bout of exercise on leptin mRNA levels in rat white adipose tissue. Male Sprague-Dawley rats were randomly assigned to an exercise or control group. Acute exercise was performed on a rodent treadmill and was carried out to exhaustion, lasting an average of 85.5 ± 1.5 min. At the end of exercise, soleus muscle and liver glycogen were reduced by 88% ( P < 0.001). Acutely exercised animals had lower ( P< 0.05) leptin mRNA levels in retroperitoneal but not epididymal fat, and this was independent of fat pad weight. To test the hypothesis that β3-adrenergic-receptor stimulation was involved in the downregulation of leptin mRNA in retroperitoneal fat, a second experiment was performed in which rats were randomized into one of four groups: control, control + β3-antagonist, exercise, and exercise + β3-antagonist. A highly selective β3-antagonist (SR-59230A) or vehicle was given by gavage 30 min before exercise or control experiment. Exercise consisted of 55 min of treadmill running, sufficient to reduce liver and muscle glycogen by 70 and 80%, respectively (both P < 0.0001). Again, acute exercise reduced leptin mRNA in retroperitoneal fat (exercise vs. control; P < 0.05), but β3-antagonism blocked this effect (exercise + β3-antagonist vs. control + β3-antagonist; P = 0.42). Unexpectedly, exercise increased serum leptin. This would be consistent with the idea that there are releasable, preformed pools of leptin within adipocytes. We conclude that β3-receptor stimulation is a mechanism by which acute exercise downregulates retroperitoneal adipose tissue leptin mRNA in vivo.

Influence of oral contraceptive use on growth hormone in vivo bioactivity following resistance exercise: Responses of molecular mass variants

2008 ◽  
Vol 18 (3) ◽  
pp. 238-244 ◽  
Author(s):  
William J. Kraemer ◽  
Bradley C. Nindl ◽  
Jeff S. Volek ◽  
James O. Marx ◽  
Lincoln A. Gotshalk ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Oral Contraceptive ◽  
Resistance Exercise ◽  
Molecular Mass ◽  
Contraceptive Use ◽  
Oral Contraceptive Use

scholarly journals Evaluation of Rat Muscle Structure in Pre-Menopausal Period after Regular Resistance Exercise and Taking Vitamin D and Calcium Supplements

2020 ◽  
Author(s):  
Seyedeh Zahra Hosseini Sisi ◽  
Mohammad Ali Azarbayjani ◽  
Mohammad Reza Vafaeenasab ◽  
Maghsoud Peeri ◽  
Mohammad Reza Dehghani
Keyword(s):  
Vitamin D ◽  
Resistance Training ◽  
Resistance Exercise ◽  
Muscle Fiber ◽  
Wistar Rats ◽  
Fiber Diameter ◽  
Inflammatory Cells ◽  
Control Group ◽  
Standard Diet ◽  
Calcium Supplements

Introduction: Menopause can change the musculoskeletal system by reducing estrogen hormone levels. The aim of this study was to evaluate the effect of regular resistance training accompanied by vitamins D and calcium supplements during pre-menopausal period on muscle tissues of Wistar rats’ postmenopausal period. Methods: In this experimental study, female Wistar rats were randomly divided into control, placebo, vitamins D, Calcium, excercise, vitamins D- Calcium, vitamins.D- excercise, Calcium - excercise, and vitamins.D‐ Calcium - excercise groups. Control and placebo groups were fed with a standard diet and sesame oil, respectively. The amount of calcium consumed was 35 mg / kg and the amount of vitamin D was 10000 IU during the two-month period, and in the resistance training groups, two months of training was performed with a ladder. Then ovariectomy was done and sample of the gastrocnemius muscle was taken and the diameter of muscle fiber, the number of muscle and adipocyte cell as well as the number of inflammatory cells were studied. The statistical analysis by means of one-way ANOVA and SPSS version 20 was performed. Results: Compared to the control group, the increase in the number of adipocyte cells were observed in the vitamin D, calcium-vitamin D, vitamin D-resistance exercise and placebo groups but it was not significantly different. Muscle fiber diameter significantly increased in all groups compared to the control group (P <0.001). The number of muscle cells increased significantly in the calcium-resistance exercise group (103± 9), vitamin D-resistance exercise (105 ±6.9) and calcium-vitamin D-resistance exercise (114 ± 3.16) compared to the control group, while, there was a significant increase in inflammatory cells only in the control and placebo groups (p≤0.05). Conclusion: Regular resistance exercise accompanied with vitamin D and Calcium supplements in premenopausal period can improve muscle fiber diameter and muscle cell numbers; in addition, the process of decrease in the muscle strength and muscle inflammation during menopause will be delayed.

Abstract 100: Delta Opioid Receptor Blockade Abolishes Exercise-Induced Cardioprotection Against Ischemia-Reperfusion Injury In Vivo

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Juliana P Borges ◽  
Marina Tristao ◽  
Eduardo V Tibiriçá ◽  
Marcos A Lessa
Keyword(s):  
Receptor Antagonist ◽  
Opioid Receptor ◽  
Acute Exercise ◽  
Ischemia Reperfusion ◽  
Control Group ◽  
Receptor Subtype ◽  
Kappa Receptor ◽  
Exercise Induced ◽  
Delta Receptor ◽  
And Control

Introduction: Recent studies showed that exercise enhances myocardial tolerance to ischemia-reperfusion (I-R) injury via an opioid receptor-dependent mechanism. However, the specific subtype of opioid receptor involved in this response remains to be determined. Methods: Male Wistar rats were first divided into 2 groups: exercised and control. The exercised group underwent 4 consecutive days of treadmill training (60 min at 70% of maximal oxygen consumption). The exercised group was then divided into 4 subgroups: exercised (Exe; n = 10); exercised + kappa receptor antagonist (Exe + K; n=4); exercised + delta receptor antagonist (Exe + D; n=4); exercised + mu receptor antagonist (Exe + M; n=4). Control group was also divided into 2 groups: control (Ctr; n = 10) and control sham (Sham; n = 10). To induce I-R injury, anesthetized animals were submitted to a left thoracotomy and a 30 min interventricular coronary occlusion followed by 60 min of reperfusion. The hemodynamic parameters were recorded and infarct size was post-mortem determined by double staining using TTC/Evans blue and expressed as a percentage of the area at risk. Results: As shown in the figure, Sham group showed no infarct, Exe group showed a significant reduction in the infarcted area (27.6%) when compared to Ctr group (42.0%). The pretreatment with mu and kappa receptor antagonist did not alter the cardioprotective effect of exercise. However, the pretreatment with delta receptor antagonist prevented the exercise-induced cardioprotection. Conclusions: Endogenous opioid system is involved in cardioprotection conferred by acute exercise, and delta receptor subtype seems to play an important role in this response.

scholarly journals Resistance Exercise-Induced Apelin Is Not Modulated by Higher Dietary Protein Density in Overweight Adults

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 50-50
Author(s):  
Colleen McKenna ◽  
Amadeo Salvador ◽  
Alexander Keeble ◽  
Rafael Alamilla ◽  
Susannah Scaroni ◽  
...  
Keyword(s):  
Resistance Training ◽  
Muscle Strength ◽  
Resistance Exercise ◽  
Dietary Protein ◽  
Middle Aged ◽  
Resistance Training Program ◽  
Exercise Induced ◽  
Protein Density ◽  
Middle Aged Adults ◽  
Plasma Apelin

Abstract Objectives Apelin is a putative exercise-sensitive myokine that has been shown to be associated with physical independence during aging. Physical performance is highly dependent on muscle strength, with a clear role of dietary protein (i.e., &gt; Recommended Dietary Allowance) for the maintenance of age-related muscle strength. However, the influence of dietary protein density on exercise-induced apelin remains unknown. Therefore, our aim was to evaluate plasma apelin concentrations and its relationship with muscle strength in middle-aged adults consuming differential amounts of animal-based protein during progressive resistance training. Methods 41 overweight middle-aged adults (50 ± 2 y, BMI 28 ± 1 kg · m−2, M = 19, F = 22) were stratified and randomized to consume either high protein (1.68 ± 0.06 g · kg−1·d−1) or moderate amounts of animal-based protein (1.16 ± 0.04 g · kg−1·d−1) during a 10-week weight-maintenance nutrition counseling-controlled resistance training program. Body composition was assessed by dual-energy x-ray absorptiometry. Muscle strength was assessed by one-repetition maximum (1RM) and isometric maximal voluntary contraction (MVC) at 60° knee angle. Oral glucose tolerance tests were performed at baseline and post-intervention. Results Main effects of time were observed for increases in lean body mass (P = 0.003), upper and lower body 1RM (all P ≤ 0.001), isometric MVC (P = 0.013), and plasma apelin concentrations (P = 0.007). There were no changes in body adiposity or glucose-insulin regulation (e.g., HOMA-IR, Matsuda) with the intervention (all P ≥ 0.152). Apelin was positively and significantly associated with isometric MVC (extension: r = 0.233, P = 0.047; flexion: r = 0.308, P = 0.008), but not 1RM. Conclusions Our results show that resistance training increases circulating apelin concentrations which is related to isometric strength gain. However, higher consumption of animal-based protein foods does not potentiate these resistance-exercise induced adaptations in overweight middle-aged adults. Funding Sources Funded in part by the Beef Checkoff. CFM funded by JBT Fellowship, UIUC.

scholarly journals Animal model for progressive resistance exercise: a detailed description of model and its implications for basic research in exercise

2013 ◽  
Vol 19 (1) ◽  
pp. 178-184 ◽  
Author(s):  
Ricardo Cardoso Cassilhas ◽  
Ismair Teodoro Reis ◽  
Daniel Venâncio ◽  
Jansen Fernandes ◽  
Sérgio Tufik ◽  
...  
Keyword(s):  
Resistance Training ◽  
Resistance Exercise ◽  
Electric Shock ◽  
Negative Reinforcement ◽  
Control Group ◽  
Progressive Resistance Training ◽  
Resistance Training Program ◽  
Experimental Group ◽  
Progressive Resistance Exercise ◽  
Progressive Resistance

The Several animal models have been proposed for resistance training. In addition, the results of these studies have been highly variable. Some of the studies have used negative reinforcement, electric shock or food deprivation to motivate the learning of the task. Features such as conditioning through electric shock may undermine the significance of the results or even prevent the model from being successfully executed. Due to these reasons, in this study we propose to use an adaptation of the vertical ladder climbing model for progressive resistance training in rats, albeit with a unique feature to ensure the homogeneity of the study groups: a period of adaptation to the apparatus without any negative reinforcement followed by a subsequent pairing of animals based on their ability to learn. The animals were distributed in the experimental group who were subjected to 8 weeks of a progressive resistance exercise protocol and the control group. After 8wks, the gastrocnemius, soleus, flexor digitorum longus (FDL), and plantaris muscles were removed and the cross-sectional area morphometry was obtened. The animals from experimental group showed hypertrophy [F(4, 15)=17,404, P < 0.001] for gastrocnemius [60% of hipertrophy; Control (2628,64 ± 348,50) versus Experimental (4207,77 ± 1256,52); ES=1.96; Power=0,86]; FDL [35% of hipertrophy; Control (2753,80 ± 359,54) versus Experimental (3711,84 ± 279,45); ES=2.99; Power=0.99] and plantaris [38% of hipertrophy; Control (2730,44 ± 320,56) versus Experimental (3767,30 ± 625,80); ES=2.19; Power=0.92], without modifications for soleus. All animals successfully completed the 8-week progressive resistance training program without any injuries, abandonment or death. Negative reinforcements such as electric shock were not required at any time in the experiment. In conclusion, we showed an adaptation of the previus model for progressive resistance training in rats. A period of adaptation to the apparatus without any negative reinforcement followed by a subsequent pairing of animals based on their ability to learn may be a alternative strategy for the original protocol. We also observed hypertrophy (gastrocnemius, FDL, and plantaris) showed the vality of this procolos for resistance exercise issues. The results of this study may be useful in basic/ applied neuroscience research and resistance exercise.

scholarly journals PO-138 Mechanism of Cortical Information Output after Exercise Fatigue Induced by D2DR

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Xiaoxin Wang ◽  
Ke Li ◽  
Lijuan Hou
Keyword(s):  
Substantia Nigra ◽  
Spectral Density ◽  
Electrical Activity ◽  
Power Spectral Density ◽  
Field Potential ◽  
Control Group ◽  
Blank Control Group ◽  
Power Spectral ◽  
Exercise Induced

Objective In this experiment, the Local field potential (LFPs) was observed in the substantia nigra compact and electrical activity change in corticostriatal pathway after D2DR intervention in exercise-induced fatigue rats. We analyzed the changes of DA neuron discharge and D2DR mediated corticostriatal pathway information transmission. To explore the mechanism of D2D2 mediated DA system in the information output of cortical M1 region. Methods Wistar rats were used to establish the model of exercise-induced fatigue. The rats were divided into control group (CG), 7 days fatigue group (7FG) and 24 hour recovery group (24RG). We used in vivo multichannel recording technology to record electrical activity in the M1, striatum and substantia nigra compact of rats and observed the electrophysiological changes after D2DR intervention. We also detected the expression of TH proteins in the dorsolateral striatum before and after exercise-induced fatigue by immunohistochemistry. Results 1) Compared with group CG, the expression of TH protein in the dorsolateral area of striatum was significantly decreased in group 7FG (P<0.05). 2) Compared with the CG group, the power spectral density of the θ, α and β band of the SNc was increased after seven days of exhaustion exercise(P < 0.05); After 24 hours of recovery, the PSD value decreased significantly compared with the 7FG group(P<0.05). 3)Compared with the CG group the power spectral density of alpha (7-13Hz) and beta (15-30Hz) bands in the M1 region and striatum was increased in 7FG after injection D2DR agonist(P < 0.05) . Conclusions After exercise-induced fatigue, the activity of substantia nigra was increased, and the activity of M1 and striatum was lower than that of the blank control group after the D2DR agonist  injection. As a key receptor for the DA signal system, D2DR regulates the electrical activity of the nigrostriatal DA pathway and affects the comprehensive information output of the cortex, which can be regarded as a target for exercise-induced fatigue (NSFC: 31401018,   SKXJX: 2014014, Corresponding [email protected]).

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