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PURPOSE: To evaluate the effects of wild trekking by examining, in postmenopausal women, the physiological adaptations to an intensive 5-day wild trek and comparing their responses to those displayed by a group of men of comparable age, training status and mountaineering skills. METHODS: Six healthy, active postmenopausal women in their sixth decade of life participated in the study. Six men of comparable age and training status were also enrolled for gender-based comparisons. The participants traversed the Selvaggio Blu wild trek (Sardinia, Italy) completing a total of 56 km, for an overall height differential of 14,301 m. During all 5-day trek, subjects were supervised by two alpine guides. Changes in body composition, cardiorespiratory fitness, and metabolic patterns of energy expenditure were evaluated before and after the intervention. RESULTS: Total energy expenditure during the trek was significantly higher (p = 0.03) in women (12.88 ± 3.37 kcal/h/kg) than men (9.27 ± 0.89 kcal/h/kg). Extracellular (ECW) and intracellular water (ICW) increased significantly following the trek only in women (ECW: - 3.8%; p = 0.01; ICW: + 3.4%; p = 0.01). The same applied to fat-free mass (+ 5.6%; p = 0.006), fat mass (- 20.4%; p = 0.006), skeletal muscle mass (+ 9.5%; p = 0.007), and appendicular muscle mass (+ 7.3%; p = 0.002). Peak VO2/kg (+ 9.4%; p = 0.05) and fat oxidation (at 80 W: + 26.96%; p = 0.04; at 100 W: + 40.95%; p = 0.02; at 120 W: + 83.02%; p = 0.01) were found increased only in women, although no concurrent changes in partial pressure of end-tidal CO2 (PETCO2) was observed. CONCLUSIONS: In postmenopausal women, a 5-day, intensive and physically/technically demanding outdoor trekking activity led to significant and potentially relevant changes in body composition, energy balance and metabolism that are generally attained following quite longer periods of training.
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Composição Corporal , Pós-Menopausa , Masculino , Humanos , Feminino , Projetos Piloto , Pós-Menopausa/fisiologia , Composição Corporal/fisiologia , Metabolismo Energético , Água , Adaptação FisiológicaRESUMO
BACKGROUND AND PURPOSE: Optimal reporting is a critical element of scholarly communications. Several initiatives, such as the EQUATOR checklists, have raised authors' awareness about the importance of adequate research reports. On these premises, we aimed at appraising the reporting quality of published randomized controlled trials (RCTs) dealing with rehabilitation interventions. Given the breadth of such literature, we focused on rehabilitation for multiple sclerosis (MS), which was taken as a model of a challenging condition for all the rehabilitation professionals.A thematic methodological survey was performed to critically examine rehabilitative RCTs published in the last 2 decades in MS populations according to 3 main reporting themes: (1) basic methodological and statistical aspects; (2) reproducibility and responsiveness of measurements; and (3) clinical meaningfulness of the change. SUMMARY OF KEY POINTS: Of the initial 526 RCTs retrieved, 370 satisfied the inclusion criteria and were included in the analysis. The survey revealed several sources of weakness affecting all the predefined themes: among these, 25.7% of the studies complemented the P values with the confidence interval of the change; 46.8% reported the effect size of the observed differences; 40.0% conducted power analyses to establish the sample size; 4.3% performed retest procedures to determine the outcomes' reproducibility and responsiveness; and 5.9% appraised the observed differences against thresholds for clinically meaningful change, for example, the minimal important change. RECOMMENDATIONS FOR CLINICAL PRACTICE: The RCTs dealing with MS rehabilitation still suffer from incomplete reporting. Adherence to evidence-based checklists and attention to measurement issues and their impact on data interpretation can improve study design and reporting in order to truly advance the field of rehabilitation in people with MS.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1 available at: http://links.lww.com/JNPT/A424 ).
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Esclerose Múltipla , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Lista de ChecagemRESUMO
PURPOSE: To explore sex-based differences in energy substrate utilization during moderate-intensity aerobic exercise; to identify the underpinning candidate physiological mechanisms. METHODS: Three databases were searched from inception to August 2020. Pertinent studies quantifying the utilization of substrates during moderate aerobic exercise in healthy men and reproductive-age women were considered. Studies conducted on sedentary/recreationally active and athletic populations were included and analyzed separately. RESULTS: Thirty-five studies entered the meta-analysis (21 in sedentary/recreationally active, 14 in athletic populations). Compared to women, the respiratory exchange ratio was significantly higher both in sedentary (mean difference, MD: + 0.03; p < 0.00001) and athletic men (MD: + 0.02; p < 0.0001). Greater carbohydrate oxidation was observed both in sedentary (standardized MD, SMD: 0.53; p = 0.006) and athletic men (SMD: 1.24; p < 0.00001). Regarding lipid substrates, sedentary men oxidized less fat than women (SMD: - 0.77; p = 0.0002), while no sex-based differences in fat oxidation were observed in athletes (SMD: 0.06; p = 0.77). Paucity of data prevented robust meta-analyses for protein sources. Sex hormones and different adrenergic activation were the most cited mechanisms to discuss sex-based differences. CONCLUSIONS: Meta-analyses confirmed that men display greater reliance on carbohydrates while women rely more on lipids to sustain moderate aerobic exercise. The latter finding was not confirmed in athletes, a novel aspect of the present study. Mechanistically driven research is needed to further dissect the physiological underpinnings of sex differences in substrate utilization during aerobic exercise, especially for proteins, which are still less investigated than other substrates.
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Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Metabolismo dos Carboidratos , Feminino , Humanos , Metabolismo dos Lipídeos , Masculino , Oxirredução , Fatores SexuaisRESUMO
The aim of this study was to establish the reproducibility of tongue strength measurements in healthy women and men during maximum anterior isometric pressure (MAIP) and regular effort saliva swallows (RESS). In this cross-sectional study, 30 healthy young adults were required to push with the tip of the tongue on a piezo-resistive sensor glued to the hard palate, immediately above the central incisor line. Tongue pressures exerted on the sensor during MAIP and spontaneous RESS were recorded. Participants underwent a retest procedure within the same session to verify the reproducibility of measurements, as determined by intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimum detectable change (MDC). Complete data were obtained from 30 subjects (15 women, 15 men; mean age 31.4 ± 7.8 years; mean weight 61.3 ± 9.4 kg). Compared to women, men showed a trend for generating larger MAIP (p = 0.06; d = 0.71) and RESS (p = 0.07; d = 0.69). After normalizing to body weight, height, and body mass index (BMI), such trends disappeared. At retest, MAIP and RESS proved stable and highly reliable (all ICCs ≥ 0.93) in men and women but associated to moderate variability as for SEM and MDC, with MAIP estimates associated to smaller SEM and MDC (SEM ranging 7.4-14.2%; MDC 18.6-20.9%) than RESS (SEM ranging 20.4-38.5%; MDC 52.5-55.6%). Piezo-resistive pressure sensors allow clinicians and researchers to perform reproducible measurements of tongue muscle performance. However, if therapeutic interventions are administered, measurement variability in tongue performance should be considered when appraising their clinical efficacy, especially for those populations who display impaired performance and may not be capable to generate high and stable forces. No gender-based differences emerged in the motor tasks tested.
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Deglutição , Saliva , Adulto , Estudos Transversais , Deglutição/fisiologia , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Pressão , Reprodutibilidade dos Testes , Língua/fisiologia , Adulto JovemRESUMO
OBJECTIVE: To compare oxygen consumption and energy expenditure (EE) of the activities of daily living (ADL) in people with multiple sclerosis (PwMS) and healthy subjects. DESIGN: Cross-sectional observational study. SETTING: Outpatient care facilities. PARTICIPANTS: Twenty-four moderately impaired PwMS and 21 healthy controls (N=45). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Oxygen consumption, EE rate, and total EE assessed by portable open-circuit spirometry during the accomplishment of a comprehensive set of 14 ADL. Body composition was also assessed with bioelectrical impedance analysis. Body cell mass was used to normalize metabolic rates between groups. RESULTS: PwMS exhibited significantly higher oxygen consumption than controls in transfer and mobility tasks (walking with stairs: +10.4%, P=.04; without stairs: +15.2%, P=.002; driving: +10.4%, P=.04) and higher EE rates for walking (+13.6%, P=.01). ADL completion took significantly longer in PwMS. Consequently, when total EE to complete each ADL was considered, PwMS used significantly more energy in 10 of the 14 ADL. Of these, "climb stairs" and walking with or without stairs showed the largest differences (+100%, +99.5%, +79.3%, respectively; all P values<.0005), followed by "dressing" (+48.8%; P=.002), "laundry" (+41.7%; P=.007), and "shopping" (+40.1%; P=.003). CONCLUSIONS: Moderately disabled PwMS display oxygen consumption and EE rates during ADL that are comparable to those of matched healthy subjects, except for the activities that involve walking. Although metabolic rates were not different for the majority of ADL, PwMS showed higher total EE to complete the same activities at a comparable work intensity, which may contribute to the burden of "real-life" tiredness and fatigue typically described in this population. Importantly, the subjective Modified Fatigue Impact Scale score significantly correlated to EE and oxygen consumption of selected ADL, such as "make a bed," "driving," "clean surfaces," and "climb stairs." The joint employment of open-circuit spirometry during ADL and body composition analysis allows an accurate metabolic characterization of PwMS, who frequently complain of fatigue.
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Metabolismo Energético/fisiologia , Fadiga/fisiopatologia , Esclerose Múltipla/fisiopatologia , Consumo de Oxigênio/fisiologia , Atividades Cotidianas , Adulto , Estudos Transversais , Avaliação da Deficiência , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , EspirometriaRESUMO
BACKGROUND: This study aimed at quantifying ankle plantarflexors' resistance to passive motion (RPM) by isokinetic dynamometry and muscle activity through surface electromyography (sEMG) in persons with multiple sclerosis (PwMS) with limb stiffness and spasticity. METHODS: Slow and fast ankle dorsiflexions (from 5°/s to 210°/s) were imparted passively by an isokinetic dynamometer, and sEMG activity of plantarflexors was recorded at the same time as the square root of the moving average. Based on RPM evaluated at 5°/s, ankles were classified as more- and less-resistant as measured by average peak torque (APT). RESULTS: Measurements were obtained bilaterally from 24 PwMS (median EDSS: 5.5) with median Modified Ashworth Scale (MAS) score of 1.75. Compared to the lowest velocity inducing EMG-evident responses (120°/s), RPM increased significantly at 180°/s (+137.8 %; p < 0.0005) and 210°/s (+85.3 %; p < 0.0005) in the less-resistant side, and only at 210°/s (+113.8 %; p < 0.0005) in the more-resistant side. sEMG activity increased significantly and similarly between limbs at increasing velocities. Significant velocity-dependent increases were detected in both limbs, with no difference by side, at 180°/s (+34.5 %; p = 0.005) and 210°/s (+48.4 %; p = 0.004). Regression analyses confirmed side (ß=0.542; p < 0.0001) and speed (ß=0.238; p < 0.0001) as significant predictors of APT change, but only speed for sEMG (speed: ß=0.215; p = 0.019; side: ß=0.012; p = 0.893). Bivariate correlations revealed that RPM was associated negatively with MAS and positively with sEMG. CONCLUSION: Spasticity presented bilaterally in PwMS, with different mixed pictures of passive and reflex stiffness, both requiring attention. Combining isokinetics and sEMG allows detecting even subtle, subclinical alterations that can prompt and drive early tailored management.
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Background: Elevated oxygen cost of walking and energy equivalents are reported for highly and moderately disabled individuals with multiple sclerosis (MS). However, less is known about minimally impaired individuals. Moreover, no sex-based data on the metabolic rates of individuals with MS are available. In this cross-sectional study, the metabolic rates and temporospatial parameters of gait during overground walking in minimally disabled individuals with MS versus matched controls were quantified and whether sex-based differences occur was examined. Methods: Sixty-nine minimally impaired adults with MS (37, relapsing-remitting MS [RRMS]; 32, clinically isolated syndrome [CIS]) and 25 matched controls completed two 6-minute walking bouts at comfortable and fast speeds. The oxygen cost of walking, energy equivalents, and respiratory exchange ratio were recorded through breath-by-breath open-circuit spirometry. Gait analysis was performed via a portable electronic walkway. Results: At comfortable but not at fast speed, men with RRMS showed higher oxygen cost of walking than men with CIS (+17.9%, P = .04) and male controls (+21.3%, P = .03). In the RRMS group, men showed higher oxygen cost of walking (+19.2%, P = .04) and energy equivalents (+19.2%, P = .02) than women. Elevated oxygen cost of walking and energy equivalents in men were paralleled by significantly larger base of support and step time asymmetry during walking. Conclusions: Metabolic demands are elevated while walking in minimally disabled individuals with RRMS. Furthermore, higher energy demands occur in men, probably due to increased step symmetry and base of support. Clinicians are advised to follow energy expenditure metrics collected while walking because they can indicate a decrease in fitness, even in the early phase of MS.
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OBJECTIVE: To the best of the authors' knowledge, no data are available about the use of isokinetic resistance training for managing ankle plantarflexor spastic hypertonia in people with multiple sclerosis (MS). The aim of this proof-of-concept study was to explore the feasibility and effects of concentric contractions on spasticity-related resistance to passive motion, strength, and mobility in people with MS and ankle plantarflexor spasticity. METHODS: In this pretest/posttest case series, 5 people with MS (mean age = 53.6 [SD = 8.8] years; median Expanded Disability Status Scale score = 5; Modified Ashworth Scale range = 1-4) received 6 weeks of isokinetic resistance training of the spastic plantarflexors. Before and after the intervention, the following outcomes were assessed: average peak torque during passive robotic mobilization, isometric strength, surface electromyography (sEMG) from the spastic muscles, time to complete the 10-m Walk Test, and the Timed "Up & Go" Test. The standardized effect size was used to test pretest and posttest effects at the individual level. Group-level analyses were also performed. RESULTS: Following the training, the average peak torque recorded from the plantarflexors during passive motion at a velocity of 150 degrees per second was found to be decreased by at least 1 SD in all participants but 1, with a significant reduction at the group level of 23.8%. Conversely, no changes in sEMG activity were detected. Group-level analyses revealed that the maximal strength of the trained plantarflexors increased significantly (31.4%). Fast walking speed increased and time to complete the Timed "Up & Go" Test decreased in 4 participants, although not significantly at the group level. CONCLUSION: Isokinetic resistance training proved safe and feasible in people who had MS and ankle plantarflexor spasticity. The observed reductions in resistance to passive motion from the spastic plantarflexors in the absence of sEMG changes might suggest a mechanical rather than a neural effect of the training. IMPACT: Based on these preliminary findings, isokinetic resistance training does not exacerbate hypertonia in people with MS and ankle plantarflexor spasticity and could be safely used to manage muscle weakness in this population.
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Esclerose Múltipla , Treinamento Resistido , Humanos , Pessoa de Meia-Idade , Espasticidade Muscular , Tornozelo , Esclerose Múltipla/complicações , Articulação do Tornozelo , Debilidade Muscular , Paresia , Hipertonia Muscular , Músculo EsqueléticoRESUMO
Geographical and temporal differences of microplastic occurrence were documented in water and fish collected in 2017 and 2019 from the Giglio Island (North Tyrrhenian Sea) close to the area where the Costa Concordia sank in January 2012. Results on water samples showed a site-dependent difference, suggesting the role of surface current dynamics in the microplastic local distribution, while tested Neuston nets (200 µm and 330 µm mesh size) did not influence microplastic retention efficiency. Fish exhibited in 2019 a higher frequency of specimens positive to microplastic ingestion with respect to 2017, with an occurrence higher than those typically observed in other Mediterranean areas. Both in water and fish, fragments were the dominating shape, polypropylene and polyethylene were the prevalent polymers, without particular difference between sites and years. This study highlights the importance of applying microplastic investigation in biotic and abiotic matrices for an effective monitoring of this pollution in the marine environment.
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Microplásticos , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Monitoramento Ambiental , Peixes , Plásticos , Água do Mar , Água , Poluentes Químicos da Água/análiseRESUMO
Transparent reporting of study methods and findings can dramatically expand the reliability and impact of health research. Evidence-based reporting checklists and guidelines, such as those hosted by the EQUATOR network, provide a framework for summarizing statistics, methods and data presentation. While being increasingly used in several research fields, such trend toward better control seems in its infancy in the field of transcranial magnetic stimulation (TMS). By the present work we aimed at assessing the quality of methodological and statistical reporting of TMS-based investigations in individuals with neurological motor impairments. We completed a methodological survey of all the studies conducted in the last two decades on the application of TMS to evaluate motor impairments in individual with neurological conditions. The pre-planned literature search of three major biomedical databases resulted in 1109 articles retrieved, 571 of which satisfied the eligibility criteria. The survey revealed that most of the studies suffered from relevant methodological and statistical issues, which potentially affect data interpretation and usability. Among these, sample size calculation, indices of change other than p values, reproducibility and clinical relevance/responsiveness emerged as those elements most commonly neglected. To increase research reliability of TMS data, we recommend adhering to international initiatives like the EQUATOR, that can impact clinical research by promoting adequate reporting. In particular, we advocate an update of the submission policies of the journals active in this field in line with adjacent areas, such as neurorehabilitation, that require the uploading of completed checklists that rationalize reporting.
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Estimulação Magnética Transcraniana , Humanos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: Research on muscle performance testing reliability in people with multiple sclerosis (MS) has focused on limb performance while less is known about trunk strength and endurance. This work aims to 1) establish test-retest reliability of trunk flexion, lateral flexion, and extension strength tests, and plank, side bridge, and Biering-Sørensen endurance tests in people with MS and matched healthy controls (HCs); 2) analyze known-groups validity of these tests in people with MS and HCs; 3) to compare groups for side-to-side differences; and 4) to describe the relationships between trunk performance and functional mobility tests. METHODS: Fifteen people with MS (median Expanded Disability Status Scale = 3) and 15 HCs underwent 2 trunk isometric strength and endurance testing sessions. Mobility was evaluated by Timed Up-and-Go test. Intraclass correlation coefficient, SEM, and minimal detectable change (MDC) were calculated. Between-group differences in trunk performance were tested using the t test for independent measures. Between-group differences in an asymmetry index were analyzed by independent t test. Bivariate correlations between trunk tests and mobility were also examined. RESULTS: All trunk tests showed good-to-excellent relative reliability in both groups (intraclass correlation coefficient > 0.71). Regarding absolute reliability, strength tests were associated with low intersession variability in both groups (MDC: MS, 11.23%-36.45%; HCs, 26.60%-31.98%). Conversely, endurance tests showed higher variability scores in people with MS (MDC: MS, 69.55%-116.50%; HCs, 29.57%-54.40%). People with MS displayed significantly lower trunk performance. Likewise, the asymmetry index showed significantly higher scores in people with MS for endurance assessment but not in strength tests. Significant correlations were detected in people with MS between Timed Up-and-Go and several trunk tests (r = 0.63-0.70). CONCLUSIONS: SEM and MDC scores revealed similar consistency and variability between groups for strength tests, whereas higher variability was observed for endurance tests in people with MS. Trunk strength tests are reliable and present discriminant validity to distinguish mildly disabled people with MS from HCs. Conversely, the high measurement error and variability of the endurance tests may hinder their application in intervention programs. IMPACT: Determining the reliability and validity of the tests currently used to assess trunk function is of the greatest importance for people with MS (who show not only impaired trunk function but also wide fluctuations in performance), as it requires consistent and accurate measurements that are sensitive enough to detect minimal changes induced by rehabilitation.
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Teste de Esforço/normas , Esclerose Múltipla/fisiopatologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Tronco/fisiopatologia , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: Direct strength training (DST) is effective in managing unilateral weakness in people with multiple sclerosis (MS). Its feasibility, however, is considerably reduced if one limb is too compromised to train. In this case, contralateral strength training (CST) of the unaffected side to induce a strength transfer to the untrained homologous muscles can help to establish a strength baseline in the weaker limb, eventually allowing direct training. Limited effects for CST, however, have been reported on patient functioning. We tested the effects on dynamometric, electromyographic, and functional outcomes of a sequential combination of CST and DST of the ankle dorsiflexors in a case of MS-related foot-drop. METHODS: A 56-year-old man diagnosed with relapsing-remitting MS exhibited severe weakness of the right dorsiflexors impairing functional dorsiflexion. The intervention consisted of a 6-week CST of the unaffected dorsiflexors followed by 2 consecutive 6-week DST cycles targeting the weaker dorsiflexors. RESULTS: At baseline, the participant could not dorsiflex his right ankle but could do so after CST. Maximal strength of the affected dorsiflexors increased by 80% following CST, by 31.1% following DST-1, and by a further 44.6% after DST-2. Neuromuscular recruitment was found progressively increased, with the largest changes occurring after DST-1. Improvements in mobility and walking speed were also detected, although plantar flexors' spasticity on the Modified Ashworth Scale increased from 1+ to 2. CONCLUSION: In this case, the sequential combination of CST and DST proved a feasible approach to manage severe unilateral weakness in a patient who was not able, at least initially, to dorsiflex his weaker ankle. In this perspective, CST may prime a minimum gain in strength necessary to allow subsequent direct training.
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Articulação do Tornozelo/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/complicações , Força Muscular/fisiologia , Debilidade Muscular/reabilitação , Treinamento Resistido/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Debilidade Muscular/etiologia , Amplitude de Movimento ArticularRESUMO
OBJECTIVE: To date, no attention has been devoted to the employment of eccentric contractions to manage spasticity in multiple sclerosis. This single-system case series aimed to explore the effects of eccentric training on spasticity-related resistance to passive motion in people with multiple sclerosis with elbow flexor spasticity. METHODS: Six people with multiple sclerosis (median Expanded Disability Status Scale score = 4.8, range = 2.0-5.5; Modified Ashworth Scale [MAS] score ≤ 3) underwent a 6-week eccentric strength training of the spastic muscles. Before and after the intervention, the following outcomes were assessed: resistive peak torque (RPT), isometric strength, resting limb position, passive range of motion and active range of motion, severity of hypertonia by MAS, and numerical rating scale. At baseline, the primary outcome (RPT) was tested over 3 time points to ensure a stable measurement. The 2-SD method was used to test pre-post training effects at individual level. Group-level analyses were also performed. RESULTS: Following the intervention RPT decreased by at least 2 SDs in all participants but 1, with a significant reduction at group level of 41.6 (29.6)%. Four people with multiple sclerosis reported a reduction in perceived spasticity severity. No changes in MAS score were detected. Group-level analyses revealed that maximal strength increased significantly in the trained elbow flexors (+30.9 [9.1]%). Elbow flexion at rest was found to be significantly reduced (-35.5 [12.4]%), whereas passive range of motion (+4.6%) and active range of motion (+11.8%) significantly increased. CONCLUSION: Eccentric training is feasible and safe to manage spasticity in people with multiple sclerosis. Preliminary data showed that this protocol can reduce resistance to passive motion, also improving strength, spasticity-free range of motion, and limb positioning. IMPACT: Patients with multiple sclerosis-related spasticity and moderate-to-severe disability can benefit from adding slow submaximal eccentric contractions to the conventional management of spasticity.
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Articulação do Cotovelo/fisiopatologia , Esclerose Múltipla/complicações , Espasticidade Muscular/reabilitação , Debilidade Muscular/reabilitação , Treinamento Resistido , Adulto , Feminino , Humanos , Movimento/fisiologia , Espasticidade Muscular/fisiopatologia , Debilidade Muscular/fisiopatologia , Amplitude de Movimento Articular/fisiologiaRESUMO
BACKGROUND: Maximal strength is a predictor of functional capacity for people with multiple sclerosis (PwMS), who frequently exhibit unilateral weakness of the ankle dorsiflexors. Aims of this study were to investigate the relationships between dorsiflexors' weakness and gait speed, the effects of high-intensity training of the affected dorsiflexors on gait performance and to identify isokinetic predictors of changes in gait speed in PwMs. METHODS: Twenty patients aged 45 (10.3) years, illness duration 14.9 (8.5) years, median EDSS 3, underwent isokinetic dorsiflexors' strength testing at 10°/s and 45°/s angular velocities and gait analysis before and after a 6-week training of dorsiflexors. Pre-to-post differences in strength and gait parameters were analyzed by paired t-test; association between gait speed and isokinetic parameters was tested through correlation and regression analyses. FINDINGS: Dorsiflexors' strength (peak moment at 10°/s: +14.9%, pâ¯=â¯0.02; at 45°/s: +21.7%, pâ¯=â¯0.03) and gait parameters (speed: +9.6%; pâ¯=â¯0.004; stride time: -5.7%; pâ¯=â¯0.01; cadence: +6.2%; pâ¯=â¯0.001; ankle power: +27.5%, pâ¯=â¯0.003) increased significantly. Of the thirteen isokinetic descriptors of strength, only peak moment, maximal and total work significantly correlated with gait speed increase. Regression analyses revealed high beta coefficients only for maximal work (10°/s: Bâ¯=â¯-6.528; betaâ¯=â¯-1.825; pâ¯=â¯0.008; 45°/s: Bâ¯=â¯-1.466; betaâ¯=â¯-1.364; pâ¯=â¯0.03). INTERPRETATION: In PwMS, high-intensity training of weakened ankle dorsiflexors induced significant improvements in maximal strength and gait speed. The finding of maximal work as a significant predictor of training-induced changes in gait speed suggests that PwMS with reduced muscle work may benefit from strength training approaches aimed at increasing gait speed. Registration number: ClinicalTrials.gov Identifier: NCT02010398.