Neuromuscular and hormonal adaptations in athletes to strength training in two years

1988 ◽  
Vol 65 (6) ◽  
pp. 2406-2412 ◽  
Author(s):  
K. Hakkinen ◽  
A. Pakarinen ◽  
M. Alen ◽  
H. Kauhanen ◽  
P. V. Komi
Keyword(s):  
Strength Training ◽  
Vastus Lateralis ◽  
Serum Testosterone ◽  
Weight Lifting ◽  
Sex Hormone Binding Globulin ◽  
Strength Development ◽  
Vastus Lateralis Muscle ◽  
Leg Extension ◽  
Intensive Training

Neuromuscular and hormonal adaptations to prolonged strength training were investigated in nine elite weight lifters. The average increases occurred over the 2-yr follow-up period in the maximal neural activation (integrated electromyogram, IEMG; 4.2%, P = NS), maximal isometric leg-extension force (4.9%, P = NS), averaged concentric power index (4.1%, P = NS), total weight-lifting result (2.8%, P less than 0.05), and total mean fiber area (5.9%, P = NS) of the vastus lateralis muscle, respectively. The training period resulted in increases in the concentrations of serum testosterone from 19.8 +/- 5.3 to 25.1 +/- 5.2 nmol/l (P less than 0.05), luteinizing hormone (LH) from 8.6 +/- 0.8 to 9.1 +/- 0.8 U/l (P less than 0.05), follicle-stimulating hormone (FSH) from 4.2 +/- 2.0 to 5.3 +/- 2.3 U/l (P less than 0.01), and testosterone-to-serum sex hormone-binding globulin (SHBG) ratio (P less than 0.05). The annual mean value of the second follow-up year for the serum testosterone-to-SHBG ratio correlated significantly (r = 0.84, P less than 0.01) with the individual changes during the 2nd yr in the averaged concentric power. The present results suggest that prolonged intensive strength training in elite athletes may influence the pituitary and possibly hypothalamic levels, leading to increased serum levels of testosterone. This may create more optimal conditions to utilize more intensive training leading to increased strength development.

Resistance exercise acutely increases MHC and mixed muscle protein synthesis rates in 78–84 and 23–32 yr olds

2000 ◽  
Vol 278 (4) ◽  
pp. E620-E626 ◽  
Author(s):  
Debbie L. Hasten ◽  
Jina Pak-Loduca ◽  
Kathleen A. Obert ◽  
Kevin E. Yarasheski
Keyword(s):  
Protein Synthesis ◽  
Resistance Exercise ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Vastus Lateralis ◽  
Weight Lifting ◽  
Synthesis Rate ◽  
Vastus Lateralis Muscle ◽  
Short Term ◽  
Mixed Protein

We determined whether short-term weight-lifting exercise increases the synthesis rate of the major contractile proteins, myosin heavy chain (MHC), actin, and mixed muscle proteins in nonfrail elders and younger women and men. Fractional synthesis rates of mixed, MHC, and actin proteins were determined in seven healthy sedentary 23- to 32-yr-old and seven healthy 78- to 84-yr-old participants in paired studies done before and at the end of a 2-wk weight-lifting program. The in vivo rate of incorporation of 1-[13C]leucine into vastus lateralis MHC, actin, and mixed proteins was determined using a 14-h constant intravenous infusion of 1-[13C]leucine. Before exercise, the mixed and MHC fractional synthetic rates were lower in the older than in the younger participants ( P ≤ 0.04). Baseline actin protein synthesis rates were similar in the two groups ( P = not significant). Over a 2-wk period, participants completed ten 1- to 1.5-h weight-lifting exercise sessions: 2–3 sets per day of 9 exercises, 8–12 repetitions per set, at 60–90% of maximum voluntary muscle strength. At the end of exercise, MHC and mixed protein synthetic rates increased in the younger (88 and 121%) and older participants (105 and 182%; P < 0.001 vs. baseline). These findings indicate that MHC and mixed protein synthesis rates are reduced more than actin in advanced age. Similar to that of 23–32 yr olds, the vastus lateralis muscle in 78–84 yr olds retains the capacity to increase MHC and mixed protein synthesis rates in response to short-term resistance exercise.

Endovascular embolization of a muscular symptomatic arteriovenous malformation with Glubran 2 acrylic glue

Vascular ◽  
2014 ◽  
Vol 23 (4) ◽  
pp. 432-435
Author(s):  
Enrique M San Norberto ◽  
José A Brizuela ◽  
Álvaro Revilla ◽  
James H Taylor ◽  
Carlos Vaquero
Keyword(s):  
Arteriovenous Malformation ◽  
Vastus Lateralis ◽  
Transcatheter Embolization ◽  
Endovascular Embolization ◽  
Deep Fascia ◽  
Vastus Lateralis Muscle ◽  
Clinical Complications ◽  
Glubran 2 ◽  
Acrylic Glue

Objective Few cases of muscle arteriovenous malformations have been reported in literature to date. Case report We report the case of a 32-year-old man presenting a muscle arteriovenous malformation involving the vastus lateralis muscle with recurrent episodes of pain. The patient was treated by transcatheter embolization with Glubran 2 acrylic glue. There were no periprocedural or subsequent clinical complications, the glue resulted in successful selective occlusion and the patient showed resolution of symptoms at the six-months follow-up. Conclusions Endovascular therapy has been shown to be beneficial in patients with high surgical risks and is the treatment of choice for arteriovenous malformation lesions that extend beyond the deep fascia and involve muscle, tendon, and bone. Glubran 2 constitutes a useful tool to attempt embolization of the muscle arteriovenous malformation nidus, with easier handling and promising results.

Human neuromuscular fatigue is associated with altered Na+-K+-ATPase activity following isometric exercise

2002 ◽  
Vol 92 (4) ◽  
pp. 1585-1593 ◽  
Author(s):  
J. R. Fowles ◽  
H. J. Green ◽  
R. Tupling ◽  
S. O'Brien ◽  
B. D. Roy
Keyword(s):  
Atpase Activity ◽  
Maximal Voluntary Contraction ◽  
Vastus Lateralis ◽  
Isometric Exercise ◽  
Voluntary Contraction ◽  
Neuromuscular Fatigue ◽  
Vastus Lateralis Muscle ◽  
M Wave ◽  
Leg Extension ◽  
Muscle Action Potential

The purpose of this study was to investigate the hypothesis that reductions in Na+-K+- ATPase activity are associated with neuromuscular fatigue following isometric exercise. In control (Con) and exercised (Ex) legs, force and electromyogram were measured in 14 volunteers [age, 23.4 ± 0.7 (SE) yr] before and immediately after (PST0), 1 h after (PST1), and 4 h after (PST4) isometric, single-leg extension exercise at ∼60% of maximal voluntary contraction for 30 min using a 0.5 duty cycle (5-s contraction, 5-s rest). Tissue was obtained from vastus lateralis muscle before exercise in Con and after exercise in both the Con (PST0) and Ex legs (PST0, PST1, PST4), for the measurements of Na+-K+-ATPase activity, as determined by the 3- O-methylfluorescein phosphatase (3- O-MFPase) assay. Voluntary (maximal voluntary contraction) and elicited (10, 20, 50, 100 Hz) force was reduced 30–55% ( P < 0.05) at PST0 and did not recover by PST4. Muscle action potential (M-wave) amplitude and area (measured in the vastus medialis) and 3- O-MFPase activity at PST0-Ex were less than that at PST0-Con ( P < 0.05) by 37, 25, and 38%, respectively. M-wave area at PST1-Ex was also less than that at PST1-Con ( P < 0.05). Changes in 3- O-MFPase activity correlated to changes in M-wave area across all time points ( r = 0.38, P < 0.05, n= 45). These results demonstrate that Na+-K+- ATPase activity is reduced by sustained isometric exercise in humans from that in a matched Con leg and that this reduction in Na+-K+-ATPase activity is associated with loss of excitability as indicated by M-wave alterations.

Training-induced alterations in muscle glycogen utilization in fibre-specific types during prolonged exercise

1990 ◽  
Vol 68 (10) ◽  
pp. 1372-1376 ◽  
Author(s):  
H. J. Green ◽  
D. Smith ◽  
P. Murphy ◽  
I. Fraser
Keyword(s):  
Prolonged Exercise ◽  
Vastus Lateralis ◽  
Fibre Types ◽  
Vastus Lateralis Muscle ◽  
Type I ◽  
Glycogen Depletion ◽  
Recruitment Pattern ◽  
Intensive Training ◽  
Glycogen Concentration ◽  
The Face

Using the glycogen depletion technique, we have examined utilization of specific fibre types during prolonged submaximal exercise to investigate the recruitment pattern employed by the central nervous system to sustain force generation in the face of a progressive glycogen depletion. Six male subjects ([Formula: see text] max, 52.8 ± 2.5 mL∙kg−1∙min−1,[Formula: see text]) cycled at 59% of pretraining [Formula: see text] max (the same absolute power output) for 99.5 ± 6 min on two occasions, before training and after 10–12 days of intensive training, involving 2 h of cycling per day. Prior to the training, glycogen concentration during exercise in the type I and type IIA fibres of the vastus lateralis muscle as measured by microphotometric techniques was progressively reduced during exercise. The pattern of depletion in both of these fibre types was parallel and showed an early marked depletion amounting to 51 (p < 0.05) and 35% (p < 0.05) in the type I and type IIA fibres, respectively, during the first 15 min of exercise. At the end of exercise, glycogen levels in type I and type IIA fibres were reduced to 9 and 44% of initial levels, respectively. In contrast, glycogen concentration in type IIB fibres was not significantly (p < 0.05) altered throughout the exercise. Following training, a pronounced glycogen sparing occurred that was conspicuous in only the type I and type IIA fibres, which was most pronounced during the first 15 min of the exercise. Similar to pretraining, glycogen concentrations in type IIB fibres were unaffected by either exercise or training. These results support the hypothesis that the muscle fibre recruitment patterns are established early in exercise and that even in the face of extensive glycogen loss observed late in exercise in the lower threshold type I and type IIA fibres, the higher threshold type IIB fibres are not recruited.Key words: recruitment, fibre types (I, IIA, and IIB), prolonged exercise, glycogen depletion.

scholarly journals Exercise Training Enhances Angiogenesis-Related Gene Responses in Skeletal Muscle of Patients with Chronic Heart Failure

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1915
Author(s):  
Andrea Tryfonos ◽  
Giorgos Tzanis ◽  
Theodore Pitsolis ◽  
Eleftherios Karatzanos ◽  
Michael Koutsilieris ◽  
...  
Keyword(s):  
Heart Failure ◽  
Skeletal Muscle ◽  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Strength Training ◽  
Vastus Lateralis ◽  
Vastus Lateralis Muscle ◽  
Vascular Endothelial ◽  
Related Factors ◽  
Endothelial Growth Factor

Peripheral myopathy consists of a hallmark of heart failure (HF). Exercise enhanced skeletal muscle angiogenesis, and thus, it can be further beneficial towards the HF-induced myopathy. However, there is limited evidence regarding the exercise type that elicits optimum angiogenic responses of skeletal muscle in HF patients. This study aimed to (a) compare the effects of a high-intensity-interval-training (HIIT) or combined HIIT with strength training (COM) exercise protocol on the expression of angiogenesis-related factors in skeletal muscle of HF patients, and (b) examine the potential associations between the expression of those genes and capillarization in the trained muscles. Thirteen male patients with chronic HF (age: 51 ± 13 y; BMI: 27 ± 4 kg/m2) were randomly assigned to a 3-month exercise program that consisted of either HIIT (N = 6) or COM training (N = 7). Vastus lateralis muscle biopsies were performed pre- and post-training. RT-PCR was used to quantify the fold changes in mRNA expression of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 2 (VEGFR-2), hypoxia-inducible factor 1 alpha (HIF-1α), angiopoietin 1 (Ang-1), angiopoietin 2 (Ang-2), angiopoietin receptor (Tie2), and matrix metallopeptidase 9 (MMP-9), and immunohistochemistry to assess capillarization in skeletal muscle post-training. There was an overall increase in the expression levels of VEGF, VEGFR-2, HIF-1α, Ang2, and MMP9 post-training, while these changes were not different among groups. Changes in capillary-to-fibre ratio were found to be strongly associated with Tie2 and HIF-1α expression. This was the first study demonstrating that both HIIT and combined HIIT with strength training enhanced similarly the expression profile of angiogenic factors in skeletal muscle of HF patients, possibly driving the angiogenic program in the trained muscles, although those gene expression increases were found to be only partially related with muscle capillarization.

Ultrastructural muscle damage in young vs. older men after high-volume, heavy-resistance strength training

1999 ◽  
Vol 86 (6) ◽  
pp. 1833-1840 ◽  
Author(s):  
Stephen M. Roth ◽  
Gregory F. Martel ◽  
Frederick M. Ivey ◽  
Jeffrey T. Lemmer ◽  
Brian L. Tracy ◽  
...  
Keyword(s):  
Strength Training ◽  
Muscle Damage ◽  
Vastus Lateralis ◽  
High Volume ◽  
Older Men ◽  
Group Differences ◽  
Strength Increase ◽  
Significant Group ◽  
Leg Extension ◽  
Old Men

This study assessed ultrastructural muscle damage in young (20–30 yr old) vs. older (65–75 yr old) men after heavy-resistance strength training (HRST). Seven young and eight older subjects completed 9 wk of unilateral leg extension HRST. Five sets of 5–20 repetitions were performed 3 days/wk with variable resistance designed to subject the muscle to near-maximal loads during every repetition. Biopsies were taken from the vastus lateralis of both legs, and muscle damage was quantified via electron microscopy. Training resulted in a 27% strength increase in both groups ( P < 0.05). In biopsies before training in the trained leg and in all biopsies from untrained leg, 0–3% of muscle fibers exhibited muscle damage in both groups ( P = not significant). After HRST, 7 and 6% of fibers in the trained leg exhibited damage in the young and older men, respectively ( P < 0.05, no significant group differences). Myofibrillar damage was primarily focal, confined to one to two sarcomeres. Young and older men appear to exhibit similar levels of muscle damage at baseline and after chronic HRST.

scholarly journals Gene expression changes in vastus lateralis muscle after different strength training regimes during rehabilitation following anterior cruciate ligament reconstruction

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258635
Author(s):  
Birgit Friedmann-Bette ◽  
Holger Lornsen ◽  
Mario Parstorfer ◽  
Thomas Gwechenberger ◽  
Francesca Profit ◽  
...  
Keyword(s):  
Strength Training ◽  
Ligament Reconstruction ◽  
Muscle Wasting ◽  
Vastus Lateralis ◽  
Cruciate Ligament ◽  
Quadriceps Strength ◽  
Vastus Lateralis Muscle ◽  
Cruciate Ligament Reconstruction ◽  
Lateralis Muscle ◽  
Anterior Cruciate

Impaired muscle regeneration has repeatedly been described after anterior cruciate ligament reconstruction (ACL-R). The results of recent studies provided some evidence for negative alterations in knee extensor muscles after ACL-R causing persisting strength deficits in spite of the regain of muscle mass. Accordingly, we observed that 12 weeks of concentric/eccentric quadriceps strength training with eccentric overload (CON/ECC+) induced a significantly greater hypertrophy of the atrophied quadriceps muscle after ACL-R than conventional concentric/eccentric quadriceps strength training (CON/ECC). However, strength deficits persisted and there was an unexpected increase in the proportion of slow type I fibers instead of the expected shift towards a faster muscle phenotype after CON/ECC+. In order to shed further light on muscle recovery after ACL-R, the steady-state levels of 84 marker mRNAs were analyzed in biopsies obtained from the vastus lateralis muscle of 31 subjects before and after 12 weeks of CON/ECC+ (n = 18) or CON/ECC strength training (n = 13) during rehabilitation after ACL-R using a custom RT2 Profiler PCR array. Significant (p < 0.05) changes were detected in the expression of 26 mRNAs, several of them involved in muscle wasting/atrophy. A different pattern with regard to the strength training mode was observed for 16 mRNAs, indicating an enhanced hypertrophic stimulus, mechanical sensing or fast contractility after CON/ECC+. The effects of the type of autograft (quadriceps, QUAD, n = 19, or semitendinosus tendon, SEMI, n = 12) were reflected in the lower expression of 6 mRNAs involved in skeletal muscle hypertrophy or contractility in QUAD. In conclusion, the greater hypertrophic stimulus and mechanical stress induced by CON/ECC+ and a beginning shift towards a faster muscle phenotype after CON/ECC+ might be indicated by significant gene expression changes as well as still ongoing muscle wasting processes and a negative impact of QUAD autograft.

scholarly journals Effect of resistance training on skeletal muscle-specific force in elderly humans

2004 ◽  
Vol 96 (3) ◽  
pp. 885-892 ◽  
Author(s):  
N. D. Reeves ◽  
M. V. Narici ◽  
C. N. Maganaris
Keyword(s):  
Skeletal Muscle ◽  
Strength Training ◽  
Old Age ◽  
Vastus Lateralis ◽  
Muscle Volume ◽  
Electromyographic Activity ◽  
Specific Force ◽  
Fascicle Length ◽  
Leg Extension ◽  
Muscle Fascicle

This study assessed muscle-specific force in vivo following strength training in old age. Subjects were assigned to training ( n = 9, age 74.3 ± 3.5 yr; mean ± SD) and control ( n = 9, age 67.1 ± 2 yr) groups. Leg-extension and leg-press exercises (2 sets of 10 repetitions at 80% of the 5 repetition maximum) were performed three times/wk for 14 wk. Vastus lateralis (VL) muscle fascicle force was calculated from maximal isometric voluntary knee extensor torque with superimposed stimuli, accounting for the patella tendon moment arm length, ultrasound-based measurements of muscle architecture, and antagonist cocontraction estimated from electromyographic activity. Physiological cross-sectional area (PCSA) was calculated from the ratio of muscle volume to fascicle length. Specific force was calculated by dividing fascicle force by PCSA. Fascicle force increased by 11%, from 847.9 ± 365.3 N before to 939.3 ± 347.8 N after training ( P < 0.05). Due to a relatively greater increase in fascicle length (11%) than muscle volume (6%), PCSA remained unchanged (pretraining: 30.4 ± 8.9 cm2; posttraining: 29.1 ± 8.4 cm2; P > 0.05). Activation capacity and VL muscle root mean square electromyographic activity increased by 5 and 40%, respectively, after training ( P < 0.05), indicating increased agonist neural drive, whereas antagonist cocontraction remained unchanged ( P > 0.05). The VL muscle-specific force increased by 19%, from 27 ± 6.3 N/cm2 before to 32.1 ± 7.4 N/cm2 after training ( P < 0.01), highlighting the effectiveness of strength training for increasing the intrinsic force-producing capacity of skeletal muscle in old age.

Increased total concentration of Na-K pumps in vastus lateralis muscle of old trained human subjects

1989 ◽  
Vol 67 (6) ◽  
pp. 2491-2494 ◽  
Author(s):  
H. Klitgaard ◽  
T. Clausen
Keyword(s):  
Strength Training ◽  
Binding Sites ◽  
Vastus Lateralis ◽  
Total Concentration ◽  
Knee Extension ◽  
Entire Group ◽  
Vastus Lateralis Muscle ◽  
Ouabain Binding ◽  
Trained Subjects ◽  
Lateralis Muscle

The concentration of Na-K pumps was measured as the total capacity for [3H]ouabain binding in needle biopsies of the vastus lateralis muscle. Samples were obtained from young (28 +/- 0.2 yr) and old (68 +/- 0.6 yr) untrained control subjects and from groups of age-matched old trained subjects, who had been performing well-defined training programs at regular intervals for 12-17 yr. Measurements of maximum isometric force in knee extension showed that running and, especially, strength training produced a significant increase, whereas swim training was without effect. Both running and swim training increased endurance of knee extension, whereas strength training had a negative effect. When compared with untrained age-matched subjects, the swim-, running-, and strength-trained subjects demonstrated increased concentration of [3H]ouabain binding sites of 30% (P less than 0.01), 32% (P less than 0.05), and 40% (P less than 0.05), respectively. In the entire group of 28 individuals tested, maximum isometric strength and the concentration of [3H]ouabain binding sites showed correlation (r = 0.49, P less than 0.01). This upregulation of Na-K pump concentration might contribute to the reduction in exercise-induced hyperkalemia seen in trained subjects.

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