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Unilateral Quadriceps Fatigue Induces Greater Impairments of Ipsilateral versus Contralateral Elbow Flexors and Plantar Flexors Performance in Physically Active Young Adults.
Whitten, JHD, Hodgson, DD, Drinkwater, EJ, Prieske, O, Aboodarda, SJ, Behm, DG
Journal of sports science & medicine. 2021;(2):300-309
Abstract
Non-local muscle fatigue (NLMF) studies have examined crossover impairments of maximal voluntary force output in non-exercised, contralateral muscles as well as comparing upper and lower limb muscles. Since prior studies primarily investigated contralateral muscles, the purpose of this study was to compare NLMF effects on elbow flexors (EF) and plantar flexors (PF) force and activation (electromyography: EMG). Secondly, possible differences when testing ipsilateral or contralateral muscles with a single or repeated isometric maximum voluntary contractions (MVC) were also investigated. Twelve participants (six males: (27.3 ± 2.5 years, 186.0 ± 2.2 cm, 91.0 ± 4.1 kg; six females: 23.0 ± 1.6 years, 168.2 ± 6.7 cm, 60.0 ± 4.3 kg) attended six randomized sessions where ipsilateral or contralateral PF or EF MVC force and EMG activity (root mean square) were tested following a dominant knee extensors (KE) fatigue intervention (2×100s MVC) or equivalent rest (control). Testing involving a single MVC (5s) was completed by the ipsilateral or contralateral PF or EF prior to and immediately post-interventions. One minute after the post-intervention single MVC, a 12×5s MVCs fatigue test was completed. Two-way repeated measures ANOVAs revealed that ipsilateral EF post-fatigue force was lower (-6.6%, p = 0.04, d = 0.18) than pre-fatigue with no significant changes in the contralateral or control conditions. EF demonstrated greater fatigue indexes for the ipsilateral (9.5%, p = 0.04, d = 0.75) and contralateral (20.3%, p < 0.01, d = 1.50) EF over the PF, respectively. There were no significant differences in PF force, EMG or EF EMG post-test or during the MVCs fatigue test. The results suggest that NLMF effects are side and muscle specific where prior KE fatigue could hinder subsequent ipsilateral upper body performance and thus is an important consideration for rehabilitation, recreation and athletic programs.
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2.
Low-intensity elbow flexion eccentric contractions attenuate maximal eccentric exercise-induced muscle damage of the contralateral arm.
Chen, TC, Lin, MJ, Lai, JH, Chen, HL, Yu, HI, Nosaka, K
Journal of science and medicine in sport. 2018;(10):1068-1072
Abstract
OBJECTIVES The magnitude of muscle damage induced by maximal eccentric contractions (MaxEC) of the elbow flexors (EF) is reduced when it is preceded by low-intensity (10% of maximal voluntary isometric contraction strength) eccentric contractions (10%EC) of the same muscle, or by MaxEC of the opposite EF. This study investigated whether 10%EC would reduce the magnitude of muscle damage after MaxEC performed by the opposite arm. DESIGN Comparison among 6 groups for changes in indirect markers of muscle damage. METHOD Young (21.0±1.8years) untrained men were assigned to five experimental groups (n=13/group) that performed 30, 10%EC followed by 30 MaxEC of the other arm performed at either 1 (1d), 2 (2d), 7 (1wk), 14 (2wk) or 21days (3wk) later, and one control group that performed 30 MaxEC without 10%EC (n=13). Changes in several indirect markers of muscle damage after MaxEC were compared among the groups by mixed-design two-way ANOVAs. RESULTS No significant changes in maximal voluntary concentric contraction torque, plasma creatine kinase activity and muscle soreness were evident after 10%EC. Changes in these variables after MaxEC were smaller (p<0.05) for the 1d, 2d and 1wk groups than control group, without significant differences between the 1d, 2d and 1wk groups. No significance differences in the changes were evident among the 2wk, 3wk and control groups, except for muscle soreness showing smaller (p<0.05) increases for the 2wk and 3wk groups than control group. CONCLUSIONS These results showed that 10%EC conferred muscle damage protection to the contralateral arm that performed MaxEC.
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3.
Do dominant and non-dominant arms respond similarly to maximal eccentric exercise of the elbow flexors?
Newton, MJ, Sacco, P, Chapman, D, Nosaka, K
Journal of science and medicine in sport. 2013;(2):166-71
Abstract
OBJECTIVES Two common models to investigate the effect of interventions on muscle damage include using two groups in which one group receives an intervention while the other acts as control, and using contralateral limbs of one group. The latter model is based on the assumption that changes in markers of muscle damage are similar between limbs, but this has not been examined systematically. DESIGN This study compared changes in muscle damage markers between dominant and non-dominant arms following maximal eccentric exercise of the elbow flexors. METHODS Eighteen men performed 60 maximal eccentric elbow flexions of each arm separated by 4 weeks with the order of testing between arms randomised. Maximal voluntary isometric torque, range of motion, upper arm circumference, plasma creatine kinase (CK) activity and muscle soreness before and for 7 days following exercise were compared between arms using two-way repeated measures ANOVA. RESULTS No significant differences between arms were evident for any of the markers, but significant (P<0.05) differences between first and second bouts were evident for changes in strength, circumference and CK with smaller changes following the second bout. A poor correlation was found for the magnitude of changes in the markers between dominant and non-dominant arms, suggesting that responses to eccentric exercise were not necessarily the same between arms. CONCLUSIONS These results show that the order affected the responses of dominant and non-dominant arms to the eccentric exercise; however, the contralateral limb design appears to be usable if bout order is counterbalanced and randomised among participants.
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4.
Plasma matrix metalloproteinase-9 response to eccentric exercise of the elbow flexors.
Madden, MC, Byrnes, WC, Lebin, JA, Batliner, ME, Allen, DL
European journal of applied physiology. 2011;(8):1795-805
Abstract
Recent efforts to establish a role for plasma matrix metalloproteinase-9 (MMP-9) as a marker of exercise-induced muscle damage have been inconsistent. Methodological and experimental design issues have contributed to confusion in this area. The purpose of this study was to use a damaging eccentric arm task to evaluate the relationship between activity-induced muscle damage and plasma MMP-9 levels in humans while controlling for physical activity history and quantifying day-to-day variability of the dependent variables. Fourteen physically inactive males performed 6 sets of 10 eccentric contractions of the elbow flexors at 120% of their voluntary concentric maximum. Soreness ratings, maximum voluntary isometric strength, range of motion (ROM), limb circumference, and plasma creatine kinase (CK) and MMP-9 levels were measured at 2 time points before, immediately after, and 1, 2, 4, and 7 days post-exercise. Changes in traditional markers of muscle damage mirrored patterns previously reported in the literature, but plasma MMP-9 concentration and activity measured by ELISA and gelatin zymography were unchanged at all time points examined. Plasma levels of the MMP-9 inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), were also unchanged post-exercise. Finally, although mean MMP-9 levels were not significantly different between the two pre-exercise timepoints, the high total error of measurement and low day-to-day correlation suggest substantial within and between subject variability. Plasma MMP-9 levels are not a robust or reliable marker for eccentric exercise-induced damage of the elbow flexor musculature, though this may not preclude a role for MMPs in skeletal muscle remodeling in response to injury.
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5.
Effect of lengthening contraction velocity on muscle damage of the elbow flexors.
Chapman, DW, Newton, M, McGuigan, M, Nosaka, K
Medicine and science in sports and exercise. 2008;(5):926-33
Abstract
PURPOSE This study investigated the effect of lengthening contraction velocity on exercise-induced muscle damage. METHODS Sixteen men were placed into two groups performing either 30 (N = 8) or 210 (N = 8) maximal lengthening contractions of the elbow flexors on an isokinetic dynamometer. Dominant and nondominant arms were randomly assigned for a slow-velocity (S: 30 degrees.s(-1)) or a fast-velocity (F: 210 degrees.s(-1)) exercise separated by 14 d. Maximal voluntary strength of isometric contractions (iMVC) and isokinetic concentric contractions (cMVC), range of motion (ROM), upper-arm circumference, muscle soreness, and serum creatine kinase (CK) activity were measured before, immediately after, and 1-120 h after exercise. Changes in these measures over time were compared by a two-way repeated-measures ANOVA to examine the effect of velocity in the same number of contractions (S30 vs F30; S210 vs F210) or the effect of contraction number at the same velocity (S30 vs S210; F30 vs F210). RESULTS A significant (P < 0.05) interaction effect was evident only for iMVC between S30 and F30, but it was evident for iMVC, cMVC, ROM, and CK between S210 and F210. Changes in most of the measures were significantly (P < 0.05) smaller after 30 contractions (S30 and F30) than after 210 contractions (S210 and F210). CONCLUSION These results suggest that the effect of contraction velocity on the magnitude of muscle damage after 30 contractions is minor; however, when 210 lengthening contractions were performed, the effect of contraction velocity became conspicuous. It is concluded that fast-velocity lengthening contractions are likely to induce greater muscle damage than slow-velocity contractions; however, muscle fatigue seems to be a confounding factor for the velocity effect.
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6.
Systemic inflammatory responses to maximal versus submaximal lengthening contractions of the elbow flexors.
Peake, JM, Nosaka, K, Muthalib, M, Suzuki, K
Exercise immunology review. 2006;:72-85
Abstract
We compared changes in markers of muscle damage and systemic inflammation after submaximal and maximal lengthening muscle contractions of the elbow flexors. Using a cross-over design, 10 healthy young men not involved in resistance training completed a submaximal trial (10 sets of 60 lengthening contractions at 10% maximum isometric strength, 1 min rest between sets), followed by a maximal trial (10 sets of three lengthening contractions at 100% maximum isometric strength, 3 min rest between sets). Lengthening contractions were performed on an isokinetic dynamometer. Opposite arms were used for the submaximal and maximal trials, and the trials were separated by a minimum of two weeks. Blood was sampled before, immediately after, 1 h, 3 h, and 1-4 d after each trial. Total leukocyte and neutrophil numbers, and the serum concentration of soluble tumor necrosis factor-alpha receptor 1 were elevated after both trials (P < 0.01), but there were no differences between the trials. Serum IL-6 concentration was elevated 3 h after the submaximal contractions (P < 0.01). The concentrations of serum tumor necrosis factor-alpha, IL-1 receptor antagonist, IL-10, granulocyte-colony stimulating factor and plasma C-reactive protein remained unchanged following both trials. Maximum isometric strength and range of motion decreased significantly (P < 0.001) after both trials, and were lower from 1-4 days after the maximal contractions compared to the submaximal contractions. Plasma myoglobin concentration and creatine kinase activity, muscle soreness and upper arm circumference all increased after both trials (P < 0.01), but were not significantly different between the trials. Therefore, there were no differences in markers of systemic inflammation, despite evidence of greater muscle damage following maximal versus submaximal lengthening contractions of the elbow flexors.
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7.
Physiologically based pharmacokinetic modeling of arterial - antecubital vein concentration difference.
Levitt, DG
BMC clinical pharmacology. 2004;:2
Abstract
BACKGROUND Modeling of pharmacokinetic parameters and pharmacodynamic actions requires knowledge of the arterial blood concentration. In most cases, experimental measurements are only available for a peripheral vein (usually antecubital) whose concentration may differ significantly from both arterial and central vein concentration. METHODS A physiologically based pharmacokinetic (PBPK) model for the tissues drained by the antecubital vein (referred to as "arm") is developed. It is assumed that the "arm" is composed of tissues with identical properties (partition coefficient, blood flow/gm) as the whole body tissues plus a new "tissue" representing skin arteriovenous shunts. The antecubital vein concentration depends on the following parameters: the fraction of "arm" blood flow contributed by muscle, skin, adipose, connective tissue and arteriovenous shunts, and the flow per gram of the arteriovenous shunt. The value of these parameters was investigated using simultaneous experimental measurements of arterial and antecubital concentrations for eight solutes: ethanol, thiopental, 99Tcm-diethylene triamine pentaacetate (DTPA), ketamine, D2O, acetone, methylene chloride and toluene. A new procedure is described that can be used to determine the arterial concentration for an arbitrary solute by deconvolution of the antecubital concentration. These procedures are implemented in PKQuest, a general PBPK program that is freely distributed http://www.pkquest.com. RESULTS One set of "standard arm" parameters provides an adequate description of the arterial/antecubital vein concentration for ethanol, DTPA, thiopental and ketamine. A significantly different set of "arm" parameters was required to describe the data for D2O, acetone, methylene chloride and toluene - probably because the "arm" is in a different physiological state. CONCLUSIONS Using the set of "standard arm" parameters, the antecubital vein concentration can be used to determine the whole body PBPK model parameters for an arbitrary solute without any additional adjustable parameters. Also, the antecubital vein concentration can be used to estimate the arterial concentration for an arbitrary input for solutes for which no arterial concentration data is available.
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8.
Concentric or eccentric training effect on eccentric exercise-induced muscle damage.
Nosaka, K, Newton, M
Medicine and science in sports and exercise. 2002;(1):63-9
Abstract
PURPOSE The purpose of this study was to compare changes in muscle damage indicators following 24 maximal eccentric actions of the elbow flexors (Max-ECC) between the arms that had been previously trained either eccentrically or concentrically for 8 wk. METHODS Fifteen subjects performed three sets of 10 repetitions of eccentric training (ECC-T) with one arm and concentric training (CON-T) with the other arm once a week for 8 wk using a dumbbell representing 50% of maximal isometric force of the elbow flexors (MIF) determined at the elbow joint of 90 degrees (1.57 rad). The dumbbell was lowered from a flexed (50 degrees, 0.87 rad) to an extended elbow position (180 degrees, 3.14 rad) in 3 s for ECC-T, and lifted from the extended to the flexed position in 3 s for CON-T. Max-ECC was performed 4 wk after CON-T and 6 wk after ECC-T. Changes in MIF, range of motion (ROM), upper arm circumference (CIR), muscle soreness (SOR), and plasma creatine kinase (CK) activity were compared between the ECC-T and CON-T arms. RESULTS The first ECC-T session produced larger decreases in MIF and ROM, and larger increases in CIR and SOR compared with CON-T. CK increased significantly (P < 0.01) and peaked 4 d after the first training session, but did not increase in the following sessions. All measures changed significantly (P < 0.01) following Max-ECC; however, the changes were not significantly different between ECC-T and CON-T arms. CONCLUSION These results showed that ECC-T did not mitigate the magnitude of muscle damage more than CON-T, and CON-T did not exacerbate muscle damage.