Comparison between voluntary and stimulated contractions of the quadriceps femoris for growth hormone response and muscle damage

2008 ◽  
Vol 104 (1) ◽  
pp. 75-81 ◽  
Author(s):  
Marc Jubeau ◽  
Alessandro Sartorio ◽  
Pier Giulio Marinone ◽  
Fiorenza Agosti ◽  
Jacques Van Hoecke ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Muscle Damage ◽  
Blood Lactate ◽  
Muscle Soreness ◽  
Voluntary Exercise ◽  
Force Output ◽  
Leg Press ◽  
Before And After ◽  
Voluntary Contractions ◽  
Serum Gh

This study aimed to compare voluntary and stimulated exercise for changes in muscle strength, growth hormone (GH), blood lactate, and markers of muscle damage. Nine healthy men had two leg press exercise bouts separated by 2 wk. In the first bout, the quadriceps muscles were stimulated by biphasic rectangular pulses (75 Hz, duration 400 μs, on-off ratio 6.25–20 s) with current amplitude being consistently increased throughout 40 contractions at maximal tolerable level. In the second bout, 40 voluntary isometric contractions were performed at the same leg press force output as the first bout. Maximal voluntary isometric strength was measured before and after the bouts, and serum GH and blood lactate concentrations were measured before, during, and after exercise. Serum creatine kinase (CK) activity and muscle soreness were assessed before, immediately after, and 24, 48, and 72 h after exercise. Maximal voluntary strength decreased significantly ( P < 0.05) after both bouts, but the magnitude of the decrease was significantly ( P < 0.05) greater for the stimulated contractions (−22%) compared with the voluntary contractions (−9%). Increases in serum GH and lactate concentrations were significantly ( P < 0.05) larger after the stimulation compared with the voluntary exercise. Increases in serum CK activity and muscle soreness were also significantly ( P < 0.05) greater for the stimulation than voluntary exercise. It was concluded that a single bout of electrical stimulation exercise resulted in greater GH response and muscle damage than voluntary exercise.

scholarly journals The Effect of Orally Dosed Levagen+™ (palmitoylethanolamide) on Exercise Recovery in Healthy Males—A Double-Blind, Randomized, Placebo-Controlled Study

Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 596 ◽  
Author(s):  
Alistair Mallard ◽  
David Briskey ◽  
Andrew Richards ◽  
Dean Mills ◽  
Amanda Rao
Keyword(s):  
Muscle Damage ◽  
Blood Lactate ◽  
Muscle Soreness ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Controlled Study ◽  
Thigh Circumference ◽  
Double Blind ◽  
Post Exercise ◽  
Leg Press

The aim of this study was to evaluate the effect of palmitoylethanolamide (PEA), a cannabimimetic compound and lipid messenger, on recovery from muscle damaging exercise. Twenty-eight healthy young male participants attended the laboratory four times on subsequent days. In the first visit, baseline characteristics were recorded before participants were randomized to consume either liquid PEA (167.5 mg Levagen+ with 832.5 mg maltodextrin) or a matched placebo (1 g maltodextrin) drink. Leg press exercise consisted of four sets at 80% of one repetition maximum followed by a performance set. Muscle soreness, thigh circumference, blood lactate concentration, biomarkers of muscle damage and inflammation, and transcription factor pathways were measured pre- and immediately post-exercise and again at 1, 2, 3, 24, 48, and 72 h post-exercise. The leg press exercise increased (p < 0.05) blood lactate concentration and induced muscle damage as evidenced by increased muscle soreness, thigh circumference, biomarkers of muscle damage, and concentrations of tumor necrosis factor-α. PEA reduced (p < 0.05) myoglobin and blood lactate concentrations and increased protein kinase B phosphorylation following exercise. Taken together, these results indicate PEA supplementation may aid in muscle recovery from repeat bouts of exercise performed within a short duration by reducing myoglobin and lactate concentration.

Influence of Oral Creatine Supplementation of Muscle Torque during Repeated Bouts of Maximal Voluntary Exercise in Man

1993 ◽  
Vol 84 (5) ◽  
pp. 565-571 ◽  
Author(s):  
Paul L. Greenhaff ◽  
Anna Casey ◽  
Anthony H. Short ◽  
Roger Harris ◽  
Karin Soderlund ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Lactate ◽  
Creatine Supplementation ◽  
Exercise Bout ◽  
Peak Torque ◽  
Voluntary Exercise ◽  
Plasma Ammonia ◽  
Muscle Torque ◽  
Before And After ◽  
Lactate Levels

1. The present experiment was undertaken to investigate the influence of oral creatine supplementation, shown previously to increase the total creatine content of human skeletal muscle (Harris RC, Soderlund K, Hultman E. Clin Sci 1992; 83: 367–74), on skeletal muscle isokinetic torque and the accumulation of plasma ammonia and blood lactate during five bouts of maximal exercise. 2. Twelve subjects undertook five bouts of 30 maximal voluntary isokinetic contractions, interspersed with 1 min recovery periods, before and after 5 days of placebo (4 × 6 g of glucose/day, n = 6) or creatine (4 × 5 g of creatine plus 1 g of glucose/day, n = 6) oral supplementation. Muscle torque production and plasma ammonia and blood lactate accumulation were measured during and after exercise on each treatment 3. No difference was seen when comparing muscle peak torque production during exercise before and after placebo ingestion. After creatine ingestion, muscle peak torque production was greater in all subjects during the final 10 contractions of exercise bout 1 (P <0.05), throughout the whole of exercise bouts 2 (P <0.01), 3 (P <0.05) and 4 (P = 0.057) and during contractions 11–20 of the final exercise bout (P <0.05), when compared with the corresponding measurements made before creatine ingestion. Plasma ammonia accumulation was lower during and after exercise after creatine ingestion. No differences were found when comparing blood lactate levels. 4. There is evidence to suggest that the decrease in the degree of muscle torque loss after dietary creatine supplementation may be a consequence of a creatine-induced acceleration of skeletal muscle phosphocreatine resynthesis. It is postulated that an increased availability of phosphocreatine would maintain better the required rate of ATP demand during contraction. This is supported by the observed lower accumulation of plasma ammonia during exercise after creatine ingestion.

Comparison between alternating and pulsed current electrical muscle stimulation for muscle and systemic acute responses

2010 ◽  
Vol 109 (3) ◽  
pp. 735-744 ◽  
Author(s):  
Abdulaziz Aldayel ◽  
Marc Jubeau ◽  
Michael McGuigan ◽  
Kazunori Nosaka
Keyword(s):  
Muscle Damage ◽  
Blood Lactate ◽  
Muscle Soreness ◽  
Knee Extensors ◽  
Pulsed Current ◽  
Electrical Muscle Stimulation ◽  
Maximal Voluntary Isometric Contraction ◽  
Skeletal Muscle Damage ◽  
Electrical Muscle ◽  
Muscle Damage Markers

This study compared alternating current and pulsed current electrical muscle stimulation (EMS) for torque output, skin temperature ( Tsk), blood lactate and hormonal responses, and skeletal muscle damage markers. Twelve healthy men (23–48 yr) received alternating current EMS (2.5 kHz delivered at 75 Hz, 400 μs) for the knee extensors of one leg and pulsed current (75 Hz, 400 μs) for the other leg to induce 40 isometric contractions (on-off ratio 5–15 s) at the knee joint angle of 100° (0°: full extension). The use of the legs for each condition was counterbalanced among subjects, and the two EMS bouts were separated by 2 wk. The current amplitude was consistently increased to maximally tolerable level, and the torque and perceived intensity were recorded over 40 isometric contractions. Tskof the stimulated and contralateral knee extensors were measured before, during, and for 30 min after EMS. Blood lactate, growth hormone, testosterone, insulin-like growth factor 1, testosterone, and cortisol were measured before, during, and for 45 min following EMS. Muscle damage markers included maximal voluntary isometric contraction torque, muscle soreness with a 100-mm visual analog scale, and plasma creatine kinase (CK) activity, which were measured before and 1, 24, 48, 72, and 96 h after EMS. No significant differences in the torque induced during stimulation (∼30% maximal voluntary isometric contraction) and perceived intensity were found, and changes in Tsk, blood lactate, and hormones were not significantly different between conditions. However, all of the measures showed significant ( P < 0.05) changes from baseline values. Skeletal muscle damage was evidenced by prolonged strength loss, development of muscle soreness, and increases in plasma CK activity; however, the changes in the variables were not significantly different between conditions. It is concluded that acute effects of alternating and pulsed current EMS on the stimulated muscles are similar.

Glycine stimulates growth hormone release in man

1980 ◽  
Vol 93 (3) ◽  
pp. 283-286 ◽  
Author(s):  
Kikuo Kasai ◽  
Hitoshi Suzuki ◽  
Tsutomu Nakamura ◽  
Hiroaki Shiina ◽  
Shin-Ichi Shimoda
Keyword(s):  
Growth Hormone ◽  
Blood Sugar ◽  
Normal Subjects ◽  
Serum Levels ◽  
Pituitary Function ◽  
Before And After ◽  
Sugar Levels ◽  
Dose Dependent ◽  
Serum Gh ◽  
Different Doses

Abstract. The influence of glycine, the simplest amino acid, on pituitary function has been investigated in the present study. Different doses (4, 8 or 12 g) of glycine were intravenously infused over 15 or 30 min in normal subjects. Serum levels of GH (growth hormone) and Prl (prolactin) were measured before and after the infusion, and also blood sugar levels were determined. The dose of 4 or 8 g glycine induced a significant increase in serum GH (P < 0.05 or P< 0.001, respectively); however, a more pronounced and significant increase in serum GH levels was observed after infusion at a dose of 12 g glycine (P < 0.001). It was clearly observed that the dose-dependent GH release to intravenous glycine occurred in normal subjects. On the contrary, serum Prl level was not changed significantly, and blood sugar level was transiently, but significantly (P < 0.05), increased after the infusion of 12 g glycine. The present data suggest that glycine might play an important role in the control of hypothalamic-pituitary function.

scholarly journals Effects of Transdermal Methylsulfonylmethane on Muscle Damage and Recovery Following Eccentric Exercise

2021 ◽  
Vol 30 (2) ◽  
pp. 158-166
Author(s):  
Hyeon-deok Jo ◽  
Choun-sub Kim ◽  
Maeng-kyu Kim
Keyword(s):  
Muscle Damage ◽  
Eccentric Exercise ◽  
Muscle Soreness ◽  
Random Order ◽  
Experimental Session ◽  
Maximal Voluntary Isometric Contraction ◽  
Positive Effects ◽  
Transdermal Application ◽  
Before And After ◽  
Exercise Induced

PURPOSE:The present study aimed to investigate the effects of transdermal application of methylsulfonylmethane (MSM) on muscle damage and recovery following eccentric exercise in young men.METHODS: Eleven college-aged men without any cardiovascular or orthopedic disorders underwent two sessions consisting of a control session (CS) and an experimental session (ES) in a random order with at least 2 weeks of wash-out between the sessions. The participants performed 30 maximal eccentric exercises involving their non-dominant elbow flexors in each session. Circumference, muscle soreness, range of motion, maximal voluntary isometric contraction (MVIC), and muscular echo intensity (EI) were measured to evaluate the changes in the level of exercise-induced muscle damage (EIMD). All measurements were performed at 24, 48, 72, and 96 hours after exercise and also immediately before and after exercise.RESULTS:Transdermal application of MSM in ES attenuated muscle swelling and decreased MVIC after eccentric exercise when compared with CS. Muscle soreness and EI tended to increase less rapidly and decrease more rapidly in ES than in CS.CONCLUSIONS: Transdermal application of MSM may induce relatively positive effects on EIMD and recovery following eccentric exercise when compared with the treatment that has been widely used previously.

scholarly journals Supplementation of Re-Esterified Docosahexaenoic and Eicosapentaenoic Acids Reduce Inflammatory and Muscle Damage Markers after Exercise in Endurance Athletes: A Randomized, Controlled Crossover Trial

Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 719 ◽  
Author(s):  
Domingo J. Ramos-Campo ◽  
Vicente Ávila-Gandía ◽  
Fco Javier López-Román ◽  
José Miñarro ◽  
Carlos Contreras ◽  
...  
Keyword(s):  
Muscle Damage ◽  
Muscle Soreness ◽  
Training Session ◽  
Endurance Athletes ◽  
Post Exercise ◽  
Supplementation Period ◽  
Before And After ◽  
Exercise Muscle ◽  
Double Blinded ◽  
Muscle Damage Markers

This study aimed to analyse the effect of 10 weeks of a highly concentrated docosahexaenoic acid (DHA) + eicosapentaenoic (EPA) supplementation (ratio 8:1) on strength deficit and inflammatory and muscle damage markers in athletes. Fifteen endurance athletes participated in the study. In a randomized, double-blinded cross-over controlled design, the athletes were supplemented with a re-esterified triglyceride containing 2.1 g/day of DHA + 240 mg/day of EPA or placebo for 10 weeks. After a 4-week wash out period, participants were supplemented with the opposite treatment. Before and after each supplementation period, participants performed one eccentric-induced muscle damage exercise training session (ECC). Before, post-exercise min and 24 and 48 h after exercise, muscle soreness, knee isokinetic strength and muscle damage and inflammatory markers were tested. No significant differences in strength deficit variables were found between the two conditions in any of the testing sessions. However, a significant effect was observed in IL1β (p = 0.011) and IL6 (p = 0.009), which showed significantly lower values after DHA consumption than after placebo ingestion. Moreover, a significant main effect was observed in CPK (p = 0.014) and LDH-5 (p = 0.05), in which significantly lower values were found after DHA + EPA consumption. In addition, there was a significant effect on muscle soreness (p = 0.049), lower values being obtained after DHA + EPA consumption. Ten weeks of re-esterified DHA + EPA promoted lower concentrations of inflammation and muscle damage markers and decreased muscle soreness but did not improve the strength deficit after an ECC in endurance athletes.

EFFECT OF l-DOPA ADMINISTRATION ON GROWTH HORMONE SECRETION IN NORMAL SUBJECTS AND PARKINSONIAN PATIENTS

1972 ◽  
Vol 54 (3) ◽  
pp. 425-433 ◽  
Author(s):  
F. CAVAGNINI ◽  
M. PERACCHI ◽  
G. SCOTTI ◽  
U. RAGGI ◽  
A. E. PONTIROLI ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Normal Subjects ◽  
Significant Rise ◽  
Arginine Infusion ◽  
Physiological Regulation ◽  
Gh Secretion ◽  
Before And After ◽  
Serum Gh

SUMMARY The effect of both oral and intravenous administration of l-DOPA on growth hormone (GH) secretion was studied in a group of normal volunteers: a significant rise of serum GH levels was observed in both cases. Growth hormone release in response to insulin hypoglycaemia and to arginine infusion was evaluated in a group of Parkinsonian patients before and after 25 days' treatment with l-DOPA plus a DOPA-decarboxylase inhibitor. In addition, GH response to the above stimuli was studied in a group of patients who had been under treatment for more than 6 months with l-DOPA alone. In untreated Parkinsonian patients, GH response to insulin hypoglycaemia was at the lower limit of normal range while arginine-induced GH release was significantly reduced. Treatment with l-DOPA did not increase GH responses. Some possible interpretations of the results are discussed. The findings support the possibility that dopamine plays a role in the physiological regulation of GH secretion, as in the case of luteinizing hormone, follicle-stimulating hormone and prolactin release.

scholarly journals The Effects of a High-Protein Diet on Markers of Muscle Damage Following Exercise in Active Older Adults: A Randomized, Controlled Trial

2020 ◽  
Vol 30 (5) ◽  
pp. 323-329
Author(s):  
Tom Clifford ◽  
Eleanor J. Hayes ◽  
Jadine H. Scragg ◽  
Guy Taylor ◽  
Kieran Smith ◽  
...  
Keyword(s):  
Older Adults ◽  
Creatine Kinase ◽  
Muscle Damage ◽  
Muscle Soreness ◽  
Controlled Trial ◽  
Protein Diet ◽  
Strenuous Exercise ◽  
Double Blind ◽  
Brief Assessment ◽  
Voluntary Contractions

Purpose: This study examined whether a higher protein diet following strenuous exercise can alter markers of muscle damage and inflammation in older adults. Methods: Using a double-blind, independent group design, 10 males and eight females (age 57 ± 4 years; mass 72.3 ± 5.6 kg; height 1.7 ± 6.5 m) were supplied with a higher protein (2.50 g·kg−1·day−1) or moderate protein (1.25 g·kg−1·day−1) diet for 48 hr after 140 squats with 25% of their body mass. Maximal isometric voluntary contractions, muscle soreness, creatine kinase, Brief Assessment of Mood Adapted, and inflammatory markers were measured preexercise, and 24 hr and 48 hr postexercise. Results: The maximal isometric voluntary contractions decreased postexercise (p = .001, ), but did not differ between groups (p = .822, ). Muscle soreness peaked at 24 hr post in moderate protein (44 ± 30 mm) and 48 hr post in higher protein (70 ± 46 mm; p = .005; ); however, no group differences were found (p = .585; ). Monocytes and lymphocytes significantly decreased postexercise, and eosinophils increased 24 hr postexercise (p < 0.05), but neutrophils, creatine kinase, interleukin-6, C-reactive protein, monocyte chemotactic protein-1, and Brief Assessment of Mood Adapted were unchanged by exercise or the intervention (p > .05). Conclusion: In conclusion, 2.50 g·kg−1·day−1 of protein is not more effective than 1.25 g·kg−1·day−1 for attenuating indirect markers of muscle damage and inflammation following strenuous exercise in older adults.

scholarly journals Muscle damage produced by isometric contractions in human elbow flexors

2018 ◽  
Vol 124 (2) ◽  
pp. 388-399 ◽  
Author(s):  
Trevor J. Allen ◽  
Tyson Jones ◽  
Anthony Tsay ◽  
David L. Morgan ◽  
Uwe Proske
Keyword(s):  
Muscle Damage ◽  
Muscle Soreness ◽  
Isometric Exercise ◽  
Isometric Contractions ◽  
Elbow Flexors ◽  
Disuse Atrophy ◽  
Half Maximum ◽  
Maximum Effort ◽  
Damage Process ◽  
Voluntary Contractions

Isometric exercise is often prescribed during rehabilitation from injury to maintain muscle condition and prevent disuse atrophy. However, such exercise can lead to muscle soreness and damage. Here we investigate which parameters of isometric contractions are responsible for the damage. Bouts of 30 repetitions of maximum voluntary contractions of elbow flexors in 38 subjects were carried out and peak force, soreness, and tenderness were measured before the exercise, immediately afterwards, at 2 h, and at 24 h postexercise. When one arm was held near the optimum angle for force generation (90°), the force it produced was greater by 28% than by the other arm held at a longer length (155°). However, despite the smaller contraction forces of the muscle held at the longer length, after the exercise it exhibited a greater fall in force that persisted out to 24 h (20% fall) and more delayed soreness than the muscle exercised at 90° (7% fall at 24 h). The result indicates a length dependence of the damage process for isometric contractions at maximum effort. In four additional experiments, evidence was provided that the damage occurred during the plateau of the contraction and not the rising or relaxation phases. The damage had a prompt onset and was cumulative, continuing for the duration of the contraction. We interpret our findings in terms of the nonuniform lengthening of sarcomeres during the plateau of the contractions and conclude that muscle damage from isometric exercise is minimized if carried out at lengths below the optimum, using half-maximum or smaller contractions. NEW & NOTEWORTHY Isometric exercise, where muscle contracts while the limb is held fixed, is often possible for individuals rehabilitating from injury and can help maintain muscle condition. Such exercise has been reported to cause some muscle damage and soreness. We confirm this and show that to minimize damage, exercising muscles should be held at shorter than the optimum length for force and carried out at half-maximum effort or less.

Increased serum growth hormone and somatic growth in exercising adult hamsters.

1978 ◽  
Vol 234 (6) ◽  
pp. E611 ◽  
Author(s):  
K T Borer ◽  
R P Kelch
Keyword(s):  
Growth Hormone ◽  
Food Consumption ◽  
Linear Growth ◽  
Serum Insulin ◽  
Somatic Growth ◽  
Voluntary Exercise ◽  
Serum Concentrations ◽  
Serum Growth Hormone ◽  
Ad Libitum ◽  
Serum Gh

In freely feeding adult hamsters, voluntary exercise induces accelerated somatic growth and increased food consumption that last through several days of retirement. We examined the effects of exercise on serum concentrations of growth hormone (GH) and insulin during ad libitum or restricted intake of food. Serum insulin and GH concentrations were measured by radioimmunoassays in exercising, retired, or sedentary hamsters during ad libitum or restricted intake of food. Linear growth was delayed in food-restricted, exercising hamsters until they were retired and unlimited food consumption was allowed. Serum GH concentrations were increased during exercise and after retirement; serum insulin concentrations were increased only after retirement during both dietary regimes. In food-restricted hamsters, endocrine changes were noted after 4 h of feeding but not after a 14-h fast. We conclude that 1) in adult hamsters voluntary exercise leads to increased secretion of GH even when ingested nutrients are insufficient to support increased growth, and 2) increased secretion of insulin is not related directly to exercise.

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