ORCID Profile
0000-0002-2616-2492
Current Organisation
Edith Cowan University
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Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-11-2022
DOI: 10.1249/MSS.0000000000003082
Abstract: Ultrasound-derived echo intensity (EI) has been used as a physiological marker for changes in skeletal muscle “quality” with physical training, disuse, aging, and neuromuscular disorders. However, the methodological and physiological factors influencing EI and its longitudinal change are still unclear. Here, we performed two separate experiments to investigate the effects of muscle temperature and fascicle angle, which are known to influence muscle tissue and sound wave properties and therefore affect EI. In experiment 1 ( n = 16, 28.0 ± 6.6 yr), vastus lateralis (VL) ultrasonographic images were acquired and intramuscular temperature continuously recorded for 15 min after 20 min of heating to 40.4°C ± 0.7°C using a microwave device. In experiment 2 ( n = 17, 30.2 ± 9.8 yr), VL sonographic images were obtained with the knee both fully extended (0°) and flexed to 90° and EI and fascicle angle measured post hoc . Fascicle movement was tracked during the passive knee flexion to ensure that sonographic images were obtained at the same muscle region. Knee flexion reduced muscle thickness, and we therefore reran analyses calculating EI using identical dimensions to minimize this effect. EI decreased only immediately after the passive heating, and although a moderate, negative correlation was observed between EI and temperature ( r rm = −0.36), the effect of muscle temperature was small ( β = 0.97 (−1.89 to −0.06) per degree Celsius, P = 0.051). Nonetheless, EI increased as fascicle angle decreased, and a large, negative correlation ( r rm = −0.85) was observed the effect of fascicle angle on EI was large ( β = 3.0 (−3.8 to −2.2) per degree, P 0.01), and this was maintained when analyses were performed at a constant depth of the region of interest ( β = 3.5 (−4.4 to −2.7) per degree, P 0.01). These findings support the hypothesis that fascicle angle meaningfully affects VL EI but provides weak evidence of a temperature effect in vivo . Thus, acute fascicle angle alterations should be accounted for in studies using EI measurements, and longer-term studies should consider whether changes in EI might be partly explained by a change in fascicle angle.
Publisher: Informa UK Limited
Date: 08-06-2023
Publisher: MDPI AG
Date: 20-04-2023
Abstract: A common pre-season injury prevention assessment conducted by professional football clubs is the hamstring-to-quadriceps (H:Q) strength ratio calculated by peak torque (PT). However, it is debatable whether players that present low pre-season H:Q ratios are more susceptible to further sustaining in-season hamstring strain injuries (HSI). Based upon retrospective data from a Brazilian Serie A football squad, a particular season came to our attention as ten out of seventeen (~59%) professional male football players sustained HSI. Therefore, we examined the pre-season H:Q ratios of these players. H:Q conventional (CR) and functional (FR) ratios, and the respective knee extensor/flexor PT from the limbs of players further sustaining in-season HSI (injured players, IP) were compared to the proportional number of dominant/non-dominant limbs from uninjured players (UP) in the squad. FR and CR were ~18–22% lower (p 0.01), whereas quadriceps concentric PT was ~25% greater for IP than UP (p = 0.002). Low scores of FR and CR were correlated (p 0.01) with high levels of quadriceps concentric PT (r = −0.66 to −0.77). In conclusion, players who sustained in-season HSI had lower pre-season FR and CR compared to UP, which appears to be associated with higher levels of quadriceps concentric torque than hamstring concentric or eccentric torque.
Publisher: Springer Science and Business Media LLC
Date: 04-10-0023
Publisher: Center for Open Science
Date: 27-11-2022
Abstract: The actual capacity to perform tasks, and actual fatigue, are concepts that have been thought of as inherently linked. These considerations also extend to their phenomenology, meaning the *perception(s) of* capacity or fatigue. The phenomenology of capacity or fatigue thus may be capturing the same underlying latent construct. Further, it is speculated that the actual capacity of a person to perform a given task, and their perception of that capacity, have a psychophysical relationship. The aim of this study was therefore twofold: 1) to explore the extensional equivalence of perceptions of capacity and fatigue, and 2) to explore the relationship between actual capacity and the perception of that capacity. We analysed secondary outcomes from two experiments where 21 participants performed various elbow flexion tasks with either a dumbell, or a connected adaptive resistance exercise (CARE) machine enabling measurement of actual capacity (i.e., maximal force). Mixed effects ordered beta regression models estimated the latent constructs during conditions from self-reports of perceptions of capacity and fatigue comparing the two operationalisations, and the relationship between actual capacity (i.e., % maximal force) and self-reports of perceptions of capacity. We hypothesised that, given their theoretical extensional equivalence, the latent constructs captured by self-report ratings as operationalisations of perceptions of capacity and fatigue would exhibit a strong negative relationship between each other reflecting strong identity, and a positive association albeit with weak as opposed to strong identity between actual capacity and perception of capacity. Our results appear to broadly corroborate both hypotheses. There was a very strong relationship indicating strong identity and thus extensional equivalence of perceptions of capacity and fatigue latent constructs (r = -0.989 [95% CI -0.994 to -0.981]). Further, a coarse grained directional relationship between actual capacity and the perception of capacity was present suggesting only weak identity at best. Future research should endeavour to identify conditions permitting testing of assumptions of the present work (i.e., the quantity assumption) and explore further possible psychophysical models relating actual, and perceptions of, demands, capacity, and effort to understand the impact of the former upon the latter given the conceptual relationships between them.
Publisher: Springer Science and Business Media LLC
Date: 02-05-2023
DOI: 10.1007/S40279-023-01851-Y
Abstract: For decades, researchers have observed that eccentric (ECC) muscle strength is greater than concentric (CON) muscle strength. However, knowledge of the ECC:CON strength ratio is incomplete and might inform resistance exercise prescriptions. Our purposes were to determine the magnitude of the ECC:CON ratio of human skeletal muscle in vivo and explore if sex, age, joint actions/exercises, and movement velocity impact it. A total of 340 studies were identified through searches. It was possible to analyse 1516 ECC:CON ratios, aggregated from 12,546 in iduals who made up 564 groups in 335 of the identified studies. Approximately 98% of measurements occurred on isokinetic machines. Bayesian meta-analyses were performed using log-ratios as response variables then exponentiated back to raw ratios. The overall main model estimate for the ECC:CON ratio was 1.41 (95% credible interval [CI] 1.38–1.44). The ECC:CON ratio was slightly less in men (1.38 [CI 1.34–1.41]) than women (1.47 [CI 1.43–1.51]), and greater in older adults (1.62 [CI 1.57–1.68]) than younger adults (1.39 [CI 1.36–1.42]). The ratio was similar between grouped upper-body (1.42 [CI 1.38–1.46]) and lower-body joint actions/exercises (1.40 [CI 1.37–1.44]). However, heterogeneity in the ratio existed across joint actions/exercises, with point estimates ranging from 1.32 to 2.61. The ECC:CON ratio was most greatly impacted by movement velocity, with a 0.20% increase in the ratio for every 1°/s increase in velocity. The results show that ECC muscle strength is ~ 40% greater than CON muscle strength. However, the ECC:CON ratio is greatly affected by movement velocity and to lesser extents age and sex. Differences between joint actions/exercises likely exist, but more data are needed to provide more precise estimates.
Publisher: Springer Science and Business Media LLC
Date: 25-03-2019
Publisher: American Physiological Society
Date: 05-2021
DOI: 10.1152/JAPPLPHYSIOL.01082.2020
Abstract: Maintained exercise-induced firing of group III/IV quadriceps muscle afferents counteracts known reductions in corticospinal excitability that occur with fatigue. However, the results suggest that this increased excitability is not underpinned by changes in intracortical facilitatory or inhibitory networks. These findings are not consistent with previous findings for hand muscle, which reported preserved intracortical facilitation with fatigue-related sustained group III/IV muscle afferent firing.
Publisher: Springer Science and Business Media LLC
Date: 25-04-2023
DOI: 10.1007/S40279-023-01842-Z
Abstract: Eccentric resistance exercise emphasizes active muscle lengthening against resistance. In the past 15 years, researchers and practitioners have expressed considerable interest in accentuated eccentric (i.e., eccentric overload) and eccentric- only resistance exercise as strategies for enhancing performance and preventing and rehabilitating injuries. However, delivery of eccentric resistance exercise has been challenging because of equipment limitations. Previously, we briefly introduced the concept of connected adaptive resistance exercise (CARE)—the integration of software and hardware to provide a resistance that adjusts in real time and in response to the in idual’s volitional force within and between repetitions. The aim of the current paper is to expand this discussion and explain the potential for CARE technology to improve the delivery of eccentric resistance exercise in various settings. First, we overview existing resistance exercise equipment and highlight its limitations for delivering eccentric resistance exercise. Second, we describe CARE and explain how it can accomplish accentuated eccentric and eccentric-only resistance exercise in a new way. We supplement this discussion with preliminary data collected with CARE technology in laboratory and non-laboratory environments. Finally, we discuss the potential for CARE technology to deliver eccentric resistance exercise for various purposes, e.g., research studies, rehabilitation programs, and home-based or telehealth interventions. Overall, CARE technology appears to permit completion of eccentric resistance exercise feasibly in both laboratory and non-laboratory environments and thus has implications for researchers and practitioners in the fields of sports medicine, physiotherapy, exercise physiology, and strength and conditioning. Nevertheless, formal investigations into the impact of CARE technology on participation in eccentric resistance exercise and clinical outcomes are still required.
Publisher: Wiley
Date: 02-06-2023
DOI: 10.1111/SMS.14419
Abstract: Since the 1970s, researchers have studied a potential difference in muscle fatigue (acute strength loss) between maximal eccentric (ECC max ) and concentric (CON max ) resistance exercise. However, a clear answer to whether such a difference exists has not been established. Therefore, the aim of our paper was to overview methods and results of studies that compared acute changes in muscle strength after bouts of ECC max and CON max resistance exercise. We identified 30 relevant studies. Participants were typically healthy men aged 20–40 years. Exercise usually consisted of 40–100 isokinetic ECC max and CON max repetitions of the knee extensors or elbow flexors . Both ECC max and CON max exercise caused significant strength loss, which plateaued and rarely exceeded 60% of baseline, suggesting strength preservation. In upper‐body muscles, strength loss at the end of ECC max (31.4 ± 20.4%) and CON max (33.6 ± 17.5%) exercise was similar, whereas in lower‐body muscles, strength loss was less after ECC max (13.3 ± 12.2%) than CON max (39.7 ± 13.3%) exercise. Muscle architecture and daily use of lower‐body muscles likely protects lower‐body muscles from strength loss during ECC max exercise. We also reviewed seven studies on muscle fatigue during coupled ECC max ‐CON max exercise and found similar strength loss in the ECC and CON phases. We also found evidence from three studies that more ECC than CON repetitions can be completed at equal relative loads. These results indicate that muscle fatigue may manifest differently between ECC max and CON max resistance exercise. An implication of the results is that prescriptions of ECC resistance exercise for lower‐body muscles should account for greater fatigue resilience of these muscles compared to upper‐body muscles.
Publisher: Public Library of Science (PLoS)
Date: 11-01-2022
DOI: 10.1371/JOURNAL.PONE.0262553
Abstract: Echo intensity (EI) is a novel tool for assessing muscle quality. EI has traditionally been reported as the mean of the pixel histogram, with 0 and 255 arbitrary units (A.U.) representing excellent and poor muscle quality, respectively. Recent work conducted in youth and younger and older adults suggested that analyzing specific EI bands, rather than the mean, may provide unique insights into the effectiveness of exercise and rehabilitation interventions. As our previous work showed deterioration of muscle quality after knee joint immobilization, we sought to investigate whether the increase in EI following disuse was limited to specific EI bands. Thirteen females (age = 21 yrs) underwent two weeks of left knee immobilization and ambulated via crutches. B-mode ultrasonography was utilized to obtain images of the immobilized vastus lateralis. The percentage of the total number of pixels within bands of 0–50, 51–100, 101–150, 151–200, and 201–255 A.U. was examined before and after immobilization. We also sought to determine if further sub iding the histogram into 25 A.U. bands (i.e., 0–25, 26–50, etc.) would be a more sensitive methodological approach. Immobilization resulted in a decrease in the percentage of pixels within the 0–50 A.U. band (-3.11 ± 3.98%), but an increase in the 101–150 A.U. (2.94 ± 2.64%) and 151–200 A.U. (0.93 ± 1.42%) bands. Analyses of variance on the change scores indicated that these differences were large and significant (%EI 0-50 vs. %EI 101-150 : p .001, d = 1.243) %EI 0-50 vs. %EI 151-200 : p = .043, d = 0.831). The effect size for the %EI 51-100 versus %EI 101-150 comparison was medium/large ( d = 0.762), but not statistically significant ( p = .085). Further analysis of the 25 A.U. bands indicated that the percentage of pixels within the 25–50 A.U. band decreased (-2.97 ± 3.64%), whereas the 101–125 (1.62 ± 1.47%) and 126–150 A.U. (1.18 ± 1.07%) bands increased. Comparison of the 50 A.U. and 25 A.U. band methods found that 25 A.U. bands offer little additional insight. Though studies are needed to ascertain the factors that may influence specific bands, changes in EI during muscle disuse are not homogeneous across the pixel histogram. We encourage investigators to think critically about the robustness of data obtained from EI histograms, rather than simply reporting the EI mean value, in muscle quality research.
Publisher: Wiley
Date: 23-03-2021
DOI: 10.1111/SMS.13920
Abstract: “Flexibility” tests are traditionally performed voluntarily relaxed by rotating a joint slowly however, functional activities are performed rapidly with voluntary/reflexive muscle activity. Here, we describe the reliabilities and differences in maximum ankle range of motion (ROM max ) and plantar flexor mechanical properties at several velocities and levels of voluntary force from a new test protocol on a commercially available dynamometer. Fifteen participants had their ankle joint dorsiflexed at 5, 30, and 60° s −1 in two conditions: voluntarily relaxed and while producing 40% and 60% of maximal eccentric torque. Commonly reported variables describing ROM max and resistance to stretch were subsequently calculated from torque and angle data. Absolute (coefficient of variation (CV%) and typical error) and relative (ICC 2,1 ) reliabilities were determined across two testing days (≥72 h). ROM max relative reliability was good in voluntarily relaxed tests at 30 and 60° s −1 and moderate at 5° s −1 , despite CVs ≤ 10% for all velocities. Tests performed with voluntary muscle activity were only reliable when performed at 5° s −1 , and ROM max reliability was moderate and CV ≤ 8%. For most variables, the rank order of participants differed between the slow‐velocity, relaxed test, and those performed at faster speeds or with voluntary activation, indicating different information. A person's flexibility status during voluntarily relaxed fast or active stretches tended to differ from their status in the traditional voluntarily relaxed, slow‐velocity test. Thus, “flexibility” tests should be completed under conditions of different stretch velocity and levels of muscle force production, and clinicians and researchers should consider the slightly larger between‐day variability from slow‐velocity voluntarily relaxed tests.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2014
Publisher: Informa UK Limited
Date: 06-2019
DOI: 10.1080/17461391.2019.1620863
Abstract: Match-induced fatigue of knee muscle strength and agonist-antagonist strength-ratios may affect both performance and risk of injury in soccer players. Once explosive tasks are imperative in soccer as well as hamstring strain injuries occur during high-velocity moments, rapid force capacity of this muscle group is especially important. This study evaluated the effect of match-induced fatigue on knee muscle strength and strength-ratio parameters after a single professional soccer match. Male professional soccer players (
Publisher: Elsevier BV
Date: 07-2019
DOI: 10.1016/J.JBIOMECH.2019.05.036
Abstract: During range of motion (max-ROM) tests performed on an isokinetic dynamometer, the mechanical delay between the button press (by the participant to signal their max-ROM) and the stopping of joint rotation resulting from system inertia induces errors in both max-ROM and maximum passive joint moment. The present study aimed to quantify these errors by comparing data when max-ROM was obtained from the joint position data, as usual (max-ROM
Publisher: The Company of Biologists
Date: 05-09-2023
DOI: 10.1242/BIO.060023
Abstract: ‘Muscle gear’ is calculated as the ratio of fascicle-to-muscle length change, strain, or velocity. Inconsistencies in nomenclature and definitions of gear exist across disciplines partly due to differences in fascicle (curved [Lf] vs. linear [Lf,straight]) and muscle (whole-muscle belly [Lb] vs. belly segment [Lb,segment]) length calculation methods. We tested whether these differences affect gear magnitude during passive and active muscle lengthening of human medial gastrocnemius of young men (n=13, 26.3±5.0 y) using an isokinetic dynameter. Lb, Lb,segment, Lf and Lf,straight were measured from motion analysis and ultrasound imaging data. Downshifts in belly gear but not belly segment gear occurred with muscle lengthening only during active lengthening. Muscle gear was unaffected by fascicle length measurement method (P=0.18) but differed when calculated as changes in Lb or Lb,segment (P& .01) in a length-dependent manner. Caution is therefore advised for the use and interpretation of different muscle gear calculation methods and nomenclatures in animal and human comparative physiology.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2015
Publisher: Elsevier BV
Date: 02-2018
DOI: 10.1016/J.ULTRASMEDBIO.2018.10.010
Abstract: In the work described here, our aim was to determine, in an elderly population, changes in muscle thickness (MT), cross-sectional area (CSA) and echo intensity (EI) of the quadriceps muscles at four time points (0, 5, 10 and 15 min i.e., T0, T5, T10 and T15, respectively) after changing from a standing to supine position. Twenty-one elderly participants (14 men: 68.1 ± 4.6 y 8 women: 66.8 ± 4.1 y) were evaluated at four time points. Rectus femoris CSA (RF
Publisher: Elsevier BV
Date: 03-2020
Publisher: Wiley
Date: 16-02-2023
DOI: 10.1111/SMS.14330
Abstract: Connected adaptive resistance exercise (CARE) machines are new technology purported to adjust resistance exercise loads in response to muscle fatigue. The present study examined muscle fatigue (strength loss, fatigue perceptions) during maximal eccentric‐only (ECC max ‐only), concentric‐only (CON max ‐only), and coupled ECC‐CON (ECC max ‐CON max ) bicep curl exercise on a CARE machine. Eleven men and nine women completed the three protocols in separate sessions and in random order. All protocols included 4 sets of 20 maximal effort muscle contractions. Strength loss was calculated as Set 4 set end load minus Set 1 highest load. The CARE machine's algorithm adjusted resistances automatically, permitting continued maximal effort repetitions without stopping. Consequently, all protocols caused substantial fatigue. Women were most susceptible to strength loss from exercise that included maximal efforts in the ECC phase, whereas men were most susceptible to strength loss from exercise that included maximal efforts in the CON phase. With ECC max ‐only exercise, ECC strength loss (mean ± SD) was similar between men (55.9 ± 14.1%) and women (56.4 ± 10.8%). However, with CON max ‐only exercise, men and women experienced 55.6 ± 6.2% and 35.3 ± 8.7% CON strength loss, respectively. With ECC max ‐CON max exercise, men experienced greater ECC (62.9 ± 7.7%) and CON (77.0 ± 5.3%) strength loss than women (ECC: 48.5 ± 15.7%, CON: 66.2 ± 12.1%). Heightened perceptions of fatigue and pain of the exercised limb were reported after all protocols. Women generally reported more biceps pain than men. The results illustrate CARE technology delivers ECC‐only and accentuated ECC exercise feasibly. Acute responses to repeated maximal effort bicep curl exercise with such technology might differ between men and women depending on muscle contraction type.
Publisher: Wiley
Date: 02-05-2017
DOI: 10.1111/SMS.12891
Abstract: Commonly used injury risk prediction tests such as the hamstring‐to‐quadriceps (H:Q) strength ratio appear to be poor predictors of non‐contact injury. However, these tests are typically performed in a non‐fatigued state, despite accumulated fatigue being an important risk factor for both hamstring strain ( HS ) and anterior cruciate ligament ( ACL ) injuries in professional soccer players. After the effect of different H:Q calculation methods were compared and contrasted, the influence of neuromuscular fatigue on the H:Q strength ratio and the association between fatigued and non‐fatigued ratio scores were examined. Thirty‐five professional soccer players performed a 30‐repetition isokinetic fatigue test protocol. Peak knee joint moments were computed for each repetition, and the H:Q conventional ratio (H: Q CR ) was calculated using several different, previously published, methods. Knee extensor and flexor moments were statistically decreased by the sixth repetition and continued to decrease until the end of the protocol. However, the H:Q ratio was statistically decreased at the end of the test due to a significant reduction in knee flexor moment (correlation between change in knee flexor moment and change in H:Q, r ≈.80 P .01). Moreover, H:Q measured in fatigue (ie, H: Q F atigue ) at the end of the test was greater than H: Q CR (1.25‐1.38 vs 0.70, P .01), these variables were weakly correlated ( r =.39, P =.02), and subject rankings within the cohort based on H: Q CR and H: Q F atigue were different ( r s =0.25, P =.15). The present data suggest that H:Q ratio measurement during a fatiguing test (H: Q F atigue ) provides different outcomes to the traditional H: Q CR . The observed significant hamstring fatigue and the difference, and weak correlation, between H: Q CR and H: Q F atigue indicate that useful information might be obtained with respect to the prediction of HS and ACL injury risk. The potential predictive value of H: Q F atigue warrants validation in future prospective trials.
Publisher: Springer Science and Business Media LLC
Date: 26-04-2017
DOI: 10.1007/S00421-017-3620-2
Abstract: Prolonged hospital bed rest after severe injury or disease leads to rapid muscle atrophy and strength loss. Therefore, the main aim of this study was to evaluate the efficacy of lower extremity strengthening exercises using elastic resistance that can be performed while lying in a hospital bed. Using a cross-sectional design, 22 healthy in iduals performed three consecutive repetitions of 14 different lower extremity exercises using elastic resistance, with a perceived intensity corresponding to 8 on the Borg CR-10 scale. Surface electromyography was measured on 13 lower extremity muscles and normalized to the maximal EMG (nEMG). Likewise, exercise satisfaction was evaluated by a questionnaire. All participants were able to perform all exercises without discomfort and generally rated them satisfactory. High levels of muscle activity were observed for all prime movers. For ex le, the "femoris muscle setting" exercise showed high levels of muscle activity for rectus femoris, vastus lateralis, and vastus medialis (79, 75, and 79% nEMG, respectively), while biceps femoris and semitendinosus were highly active during the prone knee flexion exercise with (72 and 71% nEMG, respectively) and without Kinesiology Tape (73 and 77% nEMG, respectively). High levels of muscle activity in the lower extremities can be achieved using elastic resistance exercises performed when lying in a hospital bed. Even though performed on healthy in iduals, the present study has the potential to provide a reference table of exercises to select from when in idualizing and progressing strengthening exercises during the early rehabilitation of bedridden in iduals.
No related grants have been discovered for Matheus Daros Pinto.