Sprint training increases human skeletal muscle Na(+)-K(+)-ATPase concentration and improves K+ regulation

1993 ◽  
Vol 75 (1) ◽  
pp. 173-180 ◽  
Author(s):  
M. J. McKenna ◽  
T. A. Schmidt ◽  
M. Hargreaves ◽  
L. Cameron ◽  
S. L. Skinner ◽  
...  

This study investigated the effects of sprint training on muscle Na(+)-K(+)-adenosinetriphosphatase (ATPase) concentration, plasma [K+] regulation, muscle performance, and fatigue during severe intermittent exercise. Six untrained male subjects underwent intensive cycle-sprint training for 7 wk. Muscle biopsies were taken at rest from the vastus lateralis muscle before and after 7 wk of training and were assayed for Na(+)-K(+)-ATPase concentration using vanadate-facilitated [3H]ouabain binding to intact samples. Before and after the training period, subjects performed four maximal 30-s exercise bouts (EB) on a cycle ergometer, each separated by a 4-min recovery. Arterialized venous blood samples were drawn immediately before and after each sprint bout and were analyzed for plasma [K+]. The work output was significantly elevated (11%) across all four EBs after training. The muscle [3H]ouabain binding site concentration was significantly increased (16%) from 333 +/- 19 to 387 +/- 15 (SE) pmol/g wet wt after training but was unchanged in muscle obtained from three control subjects. Plasma [K+] rose by 1–2 mmol/l with each EB and declined rapidly by the end of each recovery period. The increases in plasma [K+] resulting from each EB were significantly lower (19%) after training. The ratios of rise in plasma [K+] relative to work output during each EB were also significantly lower (27%) after training. The increased muscle [3H]ouabain binding site concentration and the reduced ratio of rise in [K+] relative to work output with exercise are both consistent with improved plasma and skeletal muscle K+ regulation after sprint training.

2012 ◽  
Vol 113 (10) ◽  
pp. 1505-1511 ◽  
Author(s):  
Michael J. McKenna ◽  
Ben D. Perry ◽  
Fabio R. Serpiello ◽  
Marissa K. Caldow ◽  
Pazit Levinger ◽  
...  

Aging is associated with reduced muscle mass, weakness, and increased fatigability. In skeletal muscle, the Na+-K+ pump (NKA) is important in regulating Na+-K+ gradients, membrane excitability, and thus contractility, but the effects of aging on muscle NKA are unclear. We investigated whether aging is linked with reduced muscle NKA by contrasting muscle NKA isoform gene expression and protein abundance, and NKA total content in 17 Elderly (66.8 ± 6.4 yr, mean ± SD) and 16 Young adults (23.9 ± 2.2 yr). Participants underwent peak oxygen consumption assessment and a vastus lateralis muscle biopsy, which was analyzed for NKA α1-, α2-, α3-, β1-, β2-, and β3-isoform gene expression (real-time RT-PCR), protein abundance (immunoblotting), and NKA total content ([3H]ouabain binding sites). The Elderly had lower peak oxygen consumption (−36.7%, P = 0.000), strength (−36.3%, P = 0.001), NKA α2- (−24.4%, 11.9 ± 4.4 vs. 9.0 ± 2.7 arbitrary units, P = 0.049), and NKA β3-protein abundance (−23.0%, P = 0.041) than Young. The β3-mRNA was higher in Elderly compared with Young ( P = 0.011). No differences were observed between groups for other NKA isoform mRNA or protein abundance, or for [3H]ouabain binding site content. Thus skeletal muscle in elderly individuals was characterized by decreased NKA α2- and β3-protein abundance, but unchanged α1 abundance and [3H]ouabain binding. The latter was likely caused by reduced α2 abundance with aging, preventing an otherwise higher [3H]ouabain binding that might occur with a greater membrane density in smaller muscle fibers. Further study is required to verify reduced muscle NKA α2 with aging and possible contributions to impaired exercise capability and daily living activities.


2000 ◽  
Vol 279 (1) ◽  
pp. R152-R160 ◽  
Author(s):  
Niels Ørtenblad ◽  
Per K. Lunde ◽  
Klaus Levin ◽  
Jesper L. Andersen ◽  
Preben K. Pedersen

To evaluate the effect of intermittent sprint training on sarcoplasmic reticulum (SR) function, nine young men performed a 5 wk high-intensity intermittent bicycle training, and six served as controls. SR function was evaluated from resting vastus lateralis muscle biopsies, before and after the training period. Intermittent sprint performance (ten 8-s all-out periods alternating with 32-s recovery) was enhanced 12% ( P < 0.01) after training. The 5-wk sprint training induced a significantly higher ( P < 0.05) peak rate of AgNO3-stimulated Ca2+ release from 709 (range 560–877; before) to 774 (596–977) arbitrary units Ca2+ ⋅ g protein− 1 ⋅ min− 1(after). The relative SR density of functional ryanodine receptors (RyR) remained unchanged after training; there was, however, a 48% ( P < 0.05) increase in total number of RyR. No significant differences in Ca2+ uptake rate and Ca2+-ATPase capacity were observed following the training, despite that the relative density of Ca2+-ATPase isoforms SERCA1 and SERCA2 had increased 41% and 55%, respectively ( P < 0.05). These data suggest that high-intensity training induces an enhanced peak SR Ca2+ release, due to an enhanced total volume of SR, whereas SR Ca2+ sequestration function is not altered.


1989 ◽  
Vol 66 (1) ◽  
pp. 72-78 ◽  
Author(s):  
L. Martineau ◽  
I. Jacobs

The effects of intramuscular glycogen availability on human temperature regulation were studied in eight seminude subjects immersed in 18 degrees C water for 90 min or until rectal temperature (Tre) decreased to 35.5 degrees C. Each subject was immersed three times over a 3-wk period. Each immersion followed 2.5 days of a specific dietary and/or exercise regimen designed to elicit low (L), normal (N), or high (H) glycogen levels in large skeletal muscle groups. Muscle glycogen concentration was determined in biopsies taken from the vastus lateralis muscle before and after each immersion. Intramuscular glycogen concentration before the immersion was significantly different among the L, N, and H trials (P less than 0.01), averaging 247 +/- 15, 406 +/- 23, and 548 +/- 42 (SE) mmol glucose units.kg dry muscle-1, respectively. The calculated metabolic heat production during the first 30 min of immersion was significantly lower during L compared with N or H (P less than 0.05). The rate at which Tre decreased was more rapid during the L immersion than either N or H (P less than 0.05), and the time during the immersion at which Tre first began to decrease also appeared sooner during L than N or H. The results suggest that low skeletal muscle glycogen levels are associated with more rapid body cooling during water immersion in humans. Higher than normal muscle glycogen levels, however, do not increase cold tolerance.


2011 ◽  
Vol 110 (2) ◽  
pp. 433-450 ◽  
Author(s):  
Julien Gondin ◽  
Lorenza Brocca ◽  
Elena Bellinzona ◽  
Giuseppe D'Antona ◽  
Nicola A. Maffiuletti ◽  
...  

The aim of the present study was to define the chronic effects of neuromuscular electrical stimulation (NMES) on the neuromuscular properties of human skeletal muscle. Eight young healthy male subjects were subjected to 25 sessions of isometric NMES of the quadriceps muscle over an 8-wk period. Needle biopsies were taken from the vastus lateralis muscle before and after training. The training status, myosin heavy chain (MHC) isoform distribution, and global protein pattern, as assessed by proteomic analysis, widely varied among subjects at baseline and prompted the identification of two subgroups: an “active” (ACT) group, which performed regular exercise and had a slower MHC profile, and a sedentary (SED) group, which did not perform any exercise and had a faster MHC profile. Maximum voluntary force and neural activation significantly increased after NMES in both groups (+∼30% and +∼10%, respectively). Both type 1 and 2 fibers showed significant muscle hypertrophy. After NMES, both groups showed a significant shift from MHC-2X toward MHC-2A and MHC-1, i.e., a fast-to-slow transition. Proteomic maps showing ∼500 spots were obtained before and after training in both groups. Differentially expressed proteins were identified and grouped into functional categories. The most relevant changes regarded 1) myofibrillar proteins, whose changes were consistent with a fast-to-slow phenotype shift and with a strengthening of the cytoskeleton; 2) energy production systems, whose changes indicated a glycolytic-to-oxidative shift in the metabolic profile; and 3) antioxidant defense systems, whose changes indicated an enhancement of intracellular defenses against reactive oxygen species. The adaptations in the protein pattern of the ACT and SED groups were different but were, in both groups, typical of both resistance (i.e., strength gains and hypertrophy) and endurance (i.e., a fast-to-slow shift in MHC and metabolic profile) training. These training-induced adaptations can be ascribed to the peculiar motor unit recruitment pattern associated with NMES.


1997 ◽  
Vol 152 (1) ◽  
pp. 49-57 ◽  
Author(s):  
I Dørup ◽  
T Clausen

Abstract Since adrenal steroids have been shown to upregulate the concentration of Na+–K+-ATPase in cardiac muscle, similar effects could be expected in skeletal muscle. Following infusion of dexamethasone (0·02–0·1 mg/kg per day) for 7 days in 10-week-old rats, the total concentration of [3H]ouabain-binding sites rose by up to 22–42% in soleus, extensor digitorum longus, gastrocnemius and diaphragm muscle. Dexamethasone produced no or minute changes in the Na+–K+ contents of skeletal muscle. In contrast, infusion with aldosterone (0·02–0·5 mg/kg per day) for 7 days produced hypokalemia and a graded reduction in the K+ content of skeletal muscle, which was closely correlated to a downregulation of the [3 H]ouabain-binding site concentration (r= 0·65–0·70; P<0·001). The results indicate that in skeletal muscle high doses of glucocorticoids upregulate the concentration of Na+–K+ pumps whereas mineralocorticoids induce a downregulation, which is secondary to the concomitant K+ deficiency. Since adrenalectomy produced no significant change in [3 H]ouabain-binding site concentration, basal levels of endogenous adrenal steroids seem to be of minor importance for the regulation of Na+–K+ pump concentration in skeletal muscle. Journal of Endocrinology (1997) 152, 49–57


1986 ◽  
Vol 56 (3) ◽  
pp. 519-532 ◽  
Author(s):  
Keld Kjeldsen ◽  
Maria Elisabeth Everts ◽  
Torben Clausen

1. Using vanadate-facilitated [3H]ouabain binding, the effect of semi-starvation on the total concentration of [3H]ouabain-binding sites was determined in samples of rat skeletal muscle. When 12-week-old rats were semi-starved for 1, 2 or 3 weeks on one-third to half the normal daily energy intake, the [3H]ouabain-binding site concentration in soleus muscle was reduced by 19, 24 and 25% respectively. In extensor digitorum longus, diaphragm and gastrocnemius muscles the decrease after 2 weeks of semi-starvation was 15, 18 and 17% respectively. The decrease was fully reversible within 3 d of free access to the diet. Complete deprivation of food for 5 d caused a reduction of 25% in soleus muscle [3H]ouabain-binding-siteconcentration. It was excluded that the reduction in [3H]ouabain binding was due to a reduced affinity of the binding site for [3H]ouabain.2. Semi-starvation of 12-week-old rats for 3 weeks caused a reduction of 45 and 53% in 3, 5, 3'-triiodothyronine (T3) and thyroxine (T4) levels respectively. As reduced thyroid hormone levels have previously been found to decrease [3H]ouabain-binding-siteconcentration in skeletal muscle, this points to the importance of T3 and T4 in the down-regulation of the [3H]ouabain-binding-siteconcentration in skeletal muscle with semi-starvation. Whereas potassium depletion caused a decrease in K content as well as in [3H]ouabain-binding-siteconcentration in skeletal muscles, semi-starvation caused only a tendency to a decrease in K content. Thus, K depletion is not a major cause of the reduction in [3H]ouabain-binding-siteconcentration with semi-starvation.3. Due to its high concentration of Na, K pumps, skeletal muscle has a considerable capacity for clearing K from the plasma as well as for the binding of digitalis glycosides. Semi-starvation causes a severe reduction in the total skeletal muscle pool of Na, K pumps and may therefore be associated with impairment of K tolerance and increased digitalis toxicity.


1999 ◽  
Vol 9 (2) ◽  
pp. 166-180 ◽  
Author(s):  
Michael Svensson ◽  
Christer Malm ◽  
Michail Tonkonogi ◽  
Bjǒrn Ekblom ◽  
Bertil Sjödin ◽  
...  

The aim of the present study was to investigate the concentration of ubiquinone-10 (Q10), at rest, in human skeletal muscle and blood plasma before and after a period of high-intensity training with or without Q10 supplementation. Another aim was to explore whether adenine nucleotide catabolism, lipid peroxidation, and mitochondrial function were affected by Q10 treatment. Seventeen young healthy men were assigned to either a control (placebo) or a Q10-supplementation (120 mg/day) group. Q10 supplementation resulted in a significantly higher plasma Q10/lotal cholesterol level on Days 11 and20compared with Day 1. There was no significant change in the concentration of Q10 in skeletal muscle or in isolated skeletal muscle mitochondria in either group. Plasma hypoxanthine and uric acid concentrations increased markedly after each exercise test session in both groups. After the training period, the postexercise increase in plasma hypoxanthine was markedly reduced in both groups, but the response was partially reversed after the recovery period. It was concluded that Q10 supplementation increases the concentration of Q1O in plasma but not in skeletal muscle.


2008 ◽  
Vol 33 (6) ◽  
pp. 1181-1191 ◽  
Author(s):  
Brent A. Baker ◽  
Melinda S. Hollander ◽  
Robert R. Mercer ◽  
Michael L. Kashon ◽  
Robert G. Cutlip

This study determined the age-related changes in acute events responsible for initiating skeletal muscle remodeling and (or) regeneration in the tibialis anterior muscle following a bout of stretch-shortening contractions (SSCs). Changes in muscle performance and morphology were quantified in young and old rats, following an acute exposure to adaptive SSCs at 6, 24, 48, 72, and 120 h postexposure (n = 6 for each age at each recovery period). Following SSC exposure, all performance measures were decreased in old rats throughout the 120 h acute phase. Estimates of edema were increased in the old vs. young exposed muscle at 120 h recovery. Both young and old rats displayed an increase in developmental myosin heavy chain (MHCdev+) labeling in the exposed muscle, indicating muscle regeneration. However, old rats displayed diminished MHCdev+ labeling, compared with young rats, suggesting limited remodeling and (or) regenerative capacity. Based on these data, diminished local muscle remodeling and (or) regeneration with aging may limit skeletal muscle adaptation following mechanical loading.


1993 ◽  
Vol 264 (6) ◽  
pp. C1538-C1541 ◽  
Author(s):  
H. J. Green ◽  
E. R. Chin ◽  
M. Ball-Burnett ◽  
D. Ranney

To investigate the effect of short-term training on Na(+)-K(+)-adenosine triphosphatase (ATPase) concentration in skeletal muscle and on plasma K+ homeostasis during exercise, 9 subjects performed cycle exercise for 2 h per day for 6 consecutive days at 65% of maximal aerobic power (VO2 max). Na(+)-K(+)-ATPase concentration determined from biopsies obtained from the vastus lateralis muscle using the [3H]ouabain-binding technique increased 13.6% (P < 0.05) as a result of the training (339 +/- 16 vs. 385 +/- 19 pmol/g wet wt, means +/- SE). Increases in Na(+)-K(+)-ATPase concentration were accompanied by a small but significant increase in VO2 max (3.36 +/- 0.16 vs. 3.58 +/- 0.13 l/min). The increase in arterialized plasma K+ concentration and plasma K+ content determined during continuous exercise at three different intensities (60, 79, and 94% VO2 max) was depressed (P < 0.05) following training. These results indicate that not only is training capable of inducing an upregulation in sarcolemmal Na(+)-K(+)-ATPase concentration in humans, but provided that the exercise is of sufficient intensity and duration, the upregulation can occur within the first week of training. Moreover, our findings are consistent with the notion that the increase in Na(+)-K(+)-ATPase pump concentration attenuates the loss of K+ from the working muscle.


2017 ◽  
Vol 5 (7) ◽  
pp. e13219 ◽  
Author(s):  
Victoria L. Wyckelsma ◽  
Itamar Levinger ◽  
Robyn M. Murphy ◽  
Aaron C. Petersen ◽  
Ben D. Perry ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document