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1.
Eur J Appl Physiol ; 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35522277

RESUMO

PURPOSE: Measurement of medial gastrocnemius (MG) tendon length using ultrasonography (US) requires the muscle-tendon junction (MTJ) to be located. Previously, the MG MTJ has been tracked from different proximo-distal locations near the MTJ, which could influence estimates of tendon length change due to the different characteristics of the aponeurosis and tendon. We used US to evaluate the effect of tracking point location on MG MTJ displacement during maximal and submaximal (10, 20 and 30% of the non-injured maximal) isometric plantar flexion contractions. METHODS: Displacement behaviour of MTJ was tracked from (1) the exact MTJ; and (2) from an insertion point of a muscle fascicle on the aponeurosis 1.3 ± 0.6 cm proximal to the MTJ, in both limbs of patients with unilateral Achilles tendon rupture (ATR) (n = 22, 4 females, 42 ± 9 years, 177 ± 9 cm, 79 ± 10 kg). RESULTS: In the non-injured limb, displacement (1.3 ± 0.5 cm vs. 1.1 ± 0.6 cm) and strain (6.7 ± 2.8% vs. 5.8 ± 3.3%) during maximal voluntary contraction were larger when tracking a point on the aponeurosis than when tracking the MTJ (both p < 0.001). The same was true for all contraction levels, and both limbs. CONCLUSION: Tracking a point on the aponeurosis consistently exaggerates estimates of tendon displacement, and the magnitude of this effect is contraction intensity-dependent. When quantifying displacement and strain of the Achilles tendon, the MTJ should be tracked directly, rather than tracking a surrogate point proximal to the MTJ. The latter method includes part of the aponeurosis, which due to its relative compliance, artificially increases estimates of MTJ displacement and strain.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35546126

RESUMO

The Achilles tendon (AT) is composed of three distinct in-series elastic subtendons, arising from different muscles in the triceps surae. Independent activation of any of these muscles is thought to induce sliding between the adjacent AT subtendons. We aimed to investigate displacement patterns during voluntary contraction (VOL) and selective transcutaneous stimulation of medial (MGstim) and lateral (LGstim) gastrocnemius between ruptured and healthy tendons, and to examine the representative areas of AT subtendons. Twenty-eight patients with unilateral AT rupture performed bilateral VOL at 30% of the maximal isometric un-injured plantarflexion torque. AT displacement was analysed from sagittal B-mode ultrasonography images during VOL, MGstim and LGstim. Three-way ANOVA revealed a significant two-way interaction of contraction type*location on the tendon displacement (F(10-815)=3.72, p<0.001). The subsequent two-way analysis revealed a significant contraction type*location interaction for tendon displacement (F(10-410)=3.79, p<0.001) in the un-injured limb only, where LGstim displacement pattern was significantly different from MGstim (p=0.008) and VOL (p=0.005). When comparing contraction types between limbs the there were no difference in the displacement patterns, but displacement amplitudes differed. There was no significant difference in the location of maximum or minimum displacement between limbs. The displacement pattern was not different in non-surgically treated compared to un-injured tendons one-year post rupture. Our results suggest that near the calcaneus, LG subtendon is located in the most anterior region adjacent to medial gastrocnemius. However, free tendon stiffness seems to be lower in the injured AT, leading to more displacement during electrically-induced contractions compared to the un-injured.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35313347

RESUMO

BACKGROUND: Good sit-to-stand (STS) performance is an important factor in maintaining functional independence. This study investigated whether free-living STS transition volume and intensity, assessed by a thigh-worn accelerometer, is associated with characteristics related to functional independence. METHODS: Free-living thigh-worn accelerometry was recorded continuously for three to seven days in a population-based sample of 75-, 80-, and 85-year-old community-dwelling people (479 participants; women n = 287, men n = 192). The records were used to evaluate the number and intensity (angular velocity of the sit-to-stand phase) of STS transitions. Associations with short physical performance battery (SPPB), five-times-sit-to-stand test (5xSTS), isometric knee extension force, self-reported fear of falls and self-reported difficulty in negotiating stairs were also assessed. RESULTS: The number of STS transitions, mean and maximal angular velocity was lower in older age groups (P < .05). All variables were higher in men than in women (P < .001) and were positively associated with SPPB total points, knee-extension force (r ranged from 0.18 to 0.39, all P < .001) and negatively associated with 5xSTS (r = -0.13 - -0.24, all P < .05), lower extremity functional limitations (P < . 01) fear of falls (P < .01) and stair negotiation difficulties (P < .01). CONCLUSIONS: Free-living STS characteristics were related to lower-extremity performance, lower extremity functional limitations, self-reported fear of falls and stair negotiation difficulties, which can be a sensitive indicator of impending functional decline. Moreover, STS transitions may provide an indicator of adequacy of lower-limb muscle strength among older individuals.

5.
Clin Biomech (Bristol, Avon) ; 92: 105568, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35066440

RESUMO

BACKGROUND: Achilles tendon rupture appears to alter stiffness and length of the tendon. These alterations may affect the function of tendon in force transmission and in energy storage and recovery. We studied the mechanical properties of the Achilles' tendon post-rupture and their association with function. METHODS: Twenty-four (20 males, 4 females) participants (mean age: 43 y, 176 cm, 81 kg) were recruited. Ultrasonography and dynamometry were used to assess the muscle-tendon unit morphological and mechanical properties of non-surgically treated patients 1-year post rupture. FINDINGS: Injured tendons were longer with difference of 1.8 cm (95%CI: 0.5-1.9 cm; P < 0.001), and thicker by 0.2 mm (0.2-0.3 mm; P < 0.01). Medial gastrocnemius cross-sectional area was 1.0 cm2 smaller (0.8-1.1 cm2; P < 0.001), fascicles were 0.6 cm shorter (0.5-0.7 cm; P < 0.001) and pennation angle was 2.5° higher (1.3-3.6°; P < 0.001) when compared to the uninjured limb. We found no differences between injured and uninjured tendon stiffness 1-year post-rupture (mean difference: 29.8 N/mm, -7.7-67.3 N/mm; P = 0.170). The injured tendon showed 1.8 mm (1.2-2.4 mm; P < 0.01) lower elongation during maximal voluntary isometric contractions. Patient-reported functional outcome was related to the tendon resting length (ß = 0.68, r(10) = 4.079, P = 0.002). Inter-limb differences in the medial gastrocnemius fascicle length were related to inter-limb differences in maximum contractions (ß = 1.17, r(14) = 2.808, P = 0.014). INTERPRETATION: Longer Achilles tendon resting length was associated with poorer self-evaluated functional outcome. Although the stiffness of non-surgically treated and uninjured tendons was similar 1-year post rupture, plantar flexion strength deficit was still present, possibly due to shorter medial gastrocnemius fascicle length.


Assuntos
Tendão do Calcâneo , Traumatismos dos Tendões , Tendão do Calcâneo/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Ruptura/terapia , Traumatismos dos Tendões/diagnóstico por imagem , Traumatismos dos Tendões/terapia , Ultrassonografia
6.
J Sports Sci ; 40(2): 215-225, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34636285

RESUMO

The study aims were to 1) examine profiles of perception of motor competence (PMC) in relation to actual motor competence (AMC), i.e. under-estimators (UEs), realistic estimators (REs) and over-estimators (OEs) and 2) investigate associations between the profiles and selected socioecological factors at the individual, family and environmental levels. PMC (Pictorial Scale of Perceived Movement Skill Competence) and AMC (Test of Gross Motor Development-Third Edition) were administered to a representative sample of children from 37 childcare centres in Finland (n=441;6.2±0.6yrs;52% boys). Socioecological factors were investigated using a parental questionnaire. The three profiles were formed based on age- and gender-adjusted PMC and AMC z-scores. Multinomial logistic regression showed that OEs (n=81; p=0.04) tended to be younger than REs (n=306; p=0.04) and UEs (n=54; p=0.03). Parents of OEs reported more child health and developmental issues than parents of REs (p=0.03). Parents of UEs self-reported providing more support for physical activity than parents' of REs (p=0.04). REs tended to live in denser population areas than UEs (n=54; p=0.03). Whilst PMC profiles revealed some socioecological differences, future research needs to focus on a broader range of potential correlates and untangle methodological analyses challenges to deepen the knowledge about PMC development in children.


Assuntos
Exercício Físico , Destreza Motora , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pais , Percepção , Autorrelato
7.
Diagnostics (Basel) ; 11(12)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34943517

RESUMO

OBJECTIVE: To quantify the spatial heterogeneity of displacement during voluntary isometric contraction within and between the different compartments of the quadriceps. METHODS: The thigh muscles of seven subjects were imaged on an MRI scanner while performing isometric knee extensions at 40% maximal voluntary contraction. A gated velocity-encoded phase contrast MRI sequence in axial orientations yielded tissue velocity-encoded dynamic images of the four different compartments of the thigh muscles (vastus lateralis (VL), vastus medialis (VM), vastus intermedius (VI), and rectus femoris (RF)) at three longitudinal locations of the proximal-distal length: 17.5% (proximal), 50% (middle), and 77.5% (distal). The displacement, which is the time integration of the measured velocity, was calculated along the three orthogonal axes using a tracking algorithm. RESULTS: The displacement of the muscle tissues was clearly nonuniform within each axial section as well as between the three axial locations. The ensemble average of the magnitude of the total displacement as a synthetic vector of the X, Y, and Z displacements was significantly larger in the VM at the middle location (p < 0.01), and in the VI at the distal location than in the other three muscles. The ensemble average of Z-axis displacement, which was almost aligned with the line of action, was significantly larger in VI than in the other three muscles in all three locations. Displacements of more than 20 mm were observed around the central aponeuroses, such as those between VI and the other surrounding muscles. CONCLUSIONS: These results imply that the quadriceps muscles act as one functional unit in normal force generation through the central aponeuroses despite complex behavior in each of the muscles, each of which possesses different physiological characteristics and architectures.

8.
Sensors (Basel) ; 21(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34577275

RESUMO

(1) Background: The purpose of this study was to evaluate the day-to-day variability and year-to-year reproducibility of an accelerometer-based algorithm for sit-to-stand (STS) transitions in a free-living environment among community-dwelling older adults. (2) Methods: Free-living thigh-worn accelerometry was recorded for three to seven days in 86 (women n = 55) community-dwelling older adults, on two occasions separated by one year, to evaluate the long-term consistency of free-living behavior. (3) Results: Year-to-year intraclass correlation coefficients (ICC) for the number of STS transitions were 0.79 (95% confidence interval, 0.70-0.86, p < 0.001), for mean angular velocity-0.81 (95% ci, 0.72-0.87, p < 0.001), and maximal angular velocity-0.73 (95% ci, 0.61-0.82, p < 0.001), respectively. Day-to-day ICCs were 0.63-0.72 for number of STS transitions (95% ci, 0.49-0.81, p < 0.001) and for mean angular velocity-0.75-0.80 (95% ci, 0.64-0.87, p < 0.001). Minimum detectable change (MDC) was 20.1 transitions/day for volume, 9.7°/s for mean intensity, and 31.7°/s for maximal intensity. (4) Conclusions: The volume and intensity of STS transitions monitored by a thigh-worn accelerometer and a sit-to-stand transitions algorithm are reproducible from day to day and year to year. The accelerometer can be used to reliably study STS transitions in free-living environments, which could add value to identifying individuals at increased risk for functional disability.


Assuntos
Acelerometria , Vida Independente , Idoso , Feminino , Humanos , Reprodutibilidade dos Testes , Coxa da Perna
9.
BMC Public Health ; 21(1): 1448, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301225

RESUMO

BACKGROUND: To investigate whether physical performance is independently of physical activity (PA) associated with positive and negative dimensions of mental well-being in middle-aged women. METHODS: Data were drawn from the Estrogenic Regulation of Muscle Apoptosis (ERMA) study in which women 47 to 55 years were randomly selected from the Finnish National Registry. They (n = 909) participated in measurements of physical performance (handgrip force, knee extension force, vertical jumping height, maximal walking speed, and six-minute walking distance). Both mental well-being (the Centre for Epidemiologic Studies Depression Scale, the International Positive and Negative Affect Schedule Short Form and the Satisfaction with Life Scale) and PA were self-reported. Associations between variables were analysed using multivariate linear regression modelling adjusted for body height, fat mass %, menopausal status and symptoms, marital status, parity, employment status, self-reported mental disorders, and use of psycholeptics and psychoanaleptics. PA was then entered into a separate model to explore its role in the associations. RESULTS: In the adjusted models, significant positive associations of six-minute walking distance with positive affectivity (B = 0.12, p = 0.002) and life satisfaction (B = 0.15, p = 0.033) were observed. No significant associations were observed between physical performance and depressive symptoms or negative affectivity. PA was positively associated with positive affectivity and life satisfaction and negatively with depressive symptoms across all the physical performance variables. CONCLUSIONS: Of the physical performance dimensions, aerobic component was associated with positive mental well-being independently of PA level. In relation to other physical performance components, the results point to the benefits of physical activity for mental well-being.


Assuntos
Exercício Físico , Força da Mão , Estudos Transversais , Depressão/epidemiologia , Feminino , Finlândia , Humanos , Saúde Mental , Pessoa de Meia-Idade , Desempenho Físico Funcional
10.
Front Sports Act Living ; 3: 626282, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34212135

RESUMO

European children and adolescents spend most of their daily life and especially their school hours being sedentary which may increase their risk for chronic non-communicable diseases later in life. After the curriculum reform of Finnish basic education in 2014, most of the new or renovated comprehensive schools in Finland incorporate open and flexible classroom designs. Their open learning spaces may provide students opportunities to reduce sedentary behavior during school hours. Thus, waist-worn accelerometers were used to assess classroom-based sedentary time (ST), the number of breaks from sedentary time (BST), and physical activity (PA) among cross-sectional samples of 3rd and 5th grade students during two separate academic years in a school that underwent a renovation from conventional classrooms to open learning spaces. The cohort of 5th grade students before renovation had a smaller proportion of ST from total classroom time (56.97 ± 12.24%, n = 42 vs. 67.68 ± 5.61%, n = 28, mean difference = 10.71%-points, 95%CI = -15.65 to-5.77, p < 0.001), a greater number of BST per 60 min of classroom time (7.41 ± 1.16 breaks/h vs. 9.19 ± 1.59 breaks/h, mean difference = -1.78 breaks/h, 95%CI = -2.486 to -1.079, p < 0.001) and a greater proportion of light intensity PA (28.66 ± 9.99% vs. 22.56 ± 4.59%, mean difference = 6.10%, 95%CI = 2.56 to 9.64, p = 0.001) than the 5th grade cohort assessed after renovation. The cohort of 3rd grade student had a greater proportion of moderate-to-vigorous intensity PA (MVPA) after the renovation compared to the cohort assessed before the renovation [Mean Rank (Before) = 27.22, Mean Rank (After) = 37.58, U =524.0, p = 0.033]. Despite the greater ST found in 5th graders, schools with open learning spaces may facilitate BST or MVPA as observed in the 5th and 3rd grade cohorts in open learning spaces compared to the cohorts in conventional classrooms, respectively. Future studies should seek to investigate and develop teacher practices to capitalize the potential of open classrooms to reduce ST, since classroom renovation alone may not be a sufficient intervention as of itself. Longitudinal studies utilizing randomized controlled trials are warranted.

11.
Eur J Appl Physiol ; 121(9): 2563-2571, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34089371

RESUMO

PURPOSE: Detailed exploration of physical activity accumulation with fine grading along the intensity spectrum has indicated the potential pragmatic utility of such an approach. However, it is currently unclear what sorts of accumulation patterns along particular intensity bands are found in the children and adult populations. Therefore, we conducted a comparison of activity accumulation in specific intensity bands between four distinct populations: children, adults with sedentary lifestyles, habitual joggers, habitual marathon runners. METHODS: Free-living waist-worn accelerometry records from 28 children aged 7 to 11, and 61 adults aged 25 to 35 were analysed. Activity intensity was evaluated in 5 s non-overlapping epochs as mean amplitude deviation (MAD) and normalised to acceleration intensities corresponding to walking at 3 metabolic equivalents of a task (METs). Adult data were normalised to 0.091 g MAD based on literature, and data from children to 0.170 g MAD based on laboratory experimentation. The normalised epoch values were divided into 100 intensity gradations. RESULTS: Children accumulated more activity in 0.74 to 1.58 normalised acceleration intensities (all p < 0.005) compared to adults. Adult joggers/runners accumulated more activity in normalised acceleration intensities from 7.1 to 11.1 compared to the other groups (p < 0.008). CONCLUSION: The primary bulk of children's free-living activities are of relatively low intensity not likely to provoke cardiometabolic improvement. These sorts of explorations could be used in informing intervention development aiming at optimising healthy development. Evidence is mounting to justify randomised controlled trials based on intervention targets identified based on exploring the intensity spectrum.


Assuntos
Acelerometria , Envelhecimento , Exercício Físico , Adulto , Criança , Humanos
12.
Sci Rep ; 11(1): 12521, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131258

RESUMO

We investigated the associations of peak oxygen uptake (V̇O2peak), ventilatory threshold (VT), muscle strength, motor competence (MC), and adiposity with the indicators of PA intensity during different physical activities used to create absolute PA intensity cut-offs among 35 children 7-11-years-of-age. V̇O2peak was defined as the highest V̇O2 achieved in the maximal cardiopulmonary exercise test (CPET) on a cycle ergometer, self-paced running, or running on a treadmill at 8 km/h. VT was defined from the CPET data. Peak isometric knee extensor and flexor strength was assessed by a dynamometer, MC by the Körperkoordination test für Kinder tests, and body composition by the bioelectrical impedance analysis. PA intensity was assessed using V̇O2 as a % of V̇O2reserve or V̇O2 at VT, mean amplitude deviation (MAD) measured by accelerometry, metabolic equivalent of task (MET), and muscle activity measured by textile electromyography during walking or running on a treadmill at 4, 6, and 8 km/h, playing hopscotch, walking up and down the stairs, self-paced walking, and self-paced running. Children with lower V̇O2peak, V̇O2 at VT, and MC operated at higher intensity level during given physical task than their peers with higher fitness and MC when PA intensity was expressed using relative PA intensity using V̇O2 as a % of V̇O2reserve or V̇O2 at VT (p < 0.05). MAD and METs during different tasks were not able to discriminate PA intensity between children with varying levels of physical fitness or MC. Traditionally used absolute measures of PA intensity based on accelerometry or MET underestimated PA intensity in children with lower V̇O2peak, V̇O2 at VT, and MC.


Assuntos
Exercício Físico/fisiologia , Obesidade/epidemiologia , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia , Acelerometria , Adiposidade/fisiologia , Composição Corporal/fisiologia , Criança , Pré-Escolar , Eletromiografia , Teste de Esforço , Feminino , Humanos , Masculino , Obesidade/fisiopatologia , Corrida/fisiologia , Caminhada/fisiologia
13.
BMC Womens Health ; 21(1): 133, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789654

RESUMO

BACKGROUND: Menopausal transition exposes women to an early decline in muscle force and motor function. Changes in muscle quality and function, especially in lower limbs, are crucial, as they expose individuals to increased risk of falls. To elucidate some of the related neuromuscular mechanisms, we investigated cortical inhibition and peripheral muscle twitch force potentiation in women during the early and late stages of perimenopause. METHODS: Participants were 63 women aged 48-55 years categorized as early (EP, n = 25) or late (LP, n = 38) perimenopausal according to serum follicle-stimulating hormone (FSH) levels and menstrual diaries. EP women had an irregular menstrual cycle and FSH < 25 IU/L, while LP women had an irregular cycle and > 25 IU/L. We examined motor evoked potential (MEP) and silent period (SP) elicited by transcranial magnetic stimulation (TMS), in the tibialis anterior muscle at 20%, 40%, and 60% of maximal voluntary contraction (MVC) levels, and twitch force potentiation in plantar flexors. RESULTS: EP group showed a longer SP duration in 40% MVC condition and larger motor evoked potential amplitude in 20% MVC condition compared to the LP group. No group difference was detected in twitch force potentiation; however, it correlated negatively with FSH levels. Other factors, such as age, height, body mass index, or physical activity did not explain group differences. CONCLUSIONS: Our preliminary results indicate subtle modulation in both TMS-induced inhibitory and excitatory mechanisms and twitch force potentiation in women already in the late perimenopausal stage. This suggests that the reduction of estrogens may have an accelerating role in the aging process of neuromuscular control.


Assuntos
Potencial Evocado Motor , Perimenopausa , Feminino , Humanos , Menopausa , Músculo Esquelético , Estimulação Magnética Transcraniana
14.
Physiol Meas ; 42(3)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33636716

RESUMO

Objective.Heart rate (HR) monitoring provides a convenient and inexpensive way to predict energy expenditure (EE) during physical activity. However, there is a lot of variation among individuals in the EE-HR relationship, which should be taken into account in predictions. The objective is to develop a model that allows the prediction of EE based on HR as accurately as possible and allows an improvement of the prediction using calibration measurements from the target individual.Approach.We propose a nonlinear (logistic) mixed model for EE and HR measurements and an approach to calibrate the model for a new person who does not belong to the dataset used to estimate the model. The calibration utilizes the estimated model parameters and calibration measurements of HR and EE from the person in question. We compare the results of the logistic mixed model with a simpler linear mixed model for which the calibration is easier to perform.Main results.We show that the calibration is beneficial already with only one pair of measurements on HR and EE. This is an important benefit over an individual-level model fitting, which requires a larger number of measurements. Moreover, we present an algorithm for calculating the confidence and prediction intervals of the calibrated predictions. The analysis was based on up to 11 pairs of EE and HR measurements from each of 54 individuals of a heterogeneous group of people, who performed a maximal treadmill test.Significance.The proposed method allows accurate energy expenditure predictions based on only a few calibration measurements from a new individual without access to the original dataset, thus making the approach viable for example on wearable computers.


Assuntos
Metabolismo Energético , Exercício Físico , Teste de Esforço , Frequência Cardíaca , Humanos , Monitorização Fisiológica
15.
BMC Sports Sci Med Rehabil ; 13(1): 17, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637124

RESUMO

BACKGROUND: Individuals with cerebral palsy (CP) have problems in everyday tasks such as walking and climbing stairs due to a combination of neuromuscular impairments such as spasticity, muscle weakness, reduced joint flexibility and poor coordination. Development of evidence-based interventions are in pivotal role in the development of better targeted rehabilitation of CP, and thus in maintaining their motor function and wellbeing. Our aim is to investigate the efficacy of an individually tailored, multifaceted exercise intervention (EXECP) in children and young adults with CP. EXECP is composed of strength, flexibility and gait training. Furthermore, this study aims to verify the short-term retention of the adaptations three months after the end of the EXECP intervention. METHODS: Twenty-four children and young adults with spastic CP will be recruited to participate in a 9-month research project with a 3-month training intervention, consisting of two to three 90-min sessions per week. In each session, strength training for the lower limbs and trunk muscles, flexibility training for the lower limbs and inclined treadmill gait training will be performed. We will evaluate muscle strength, joint flexibility, neuromuscular and cardiometabolic parameters. A nonconcurrent multiple baseline design with two pre-tests and two post-tests all interspaced by three months is used. In addition to the CP participants, 24 typically developing age and sex-matched participants will perform the two pre-tests (i.e. no intervention) to provide normative data. DISCUSSION: This study has a comprehensive approach examining longitudinal effects of wide variety of variables ranging from physical activity and gross motor function to sensorimotor functions of the brain and neuromuscular and cardiometabolic parameters, providing novel information about the adaptation mechanisms in cerebral palsy. To the best of our knowledge, this is the first intervention study providing supervised combined strength, flexibility and gait training for young individuals with CP. TRIAL REGISTRATION NUMBER: ISRCTN69044459, prospectively registered (21/04/2017).

16.
J Sports Sci ; 39(12): 1428-1435, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33467987

RESUMO

We investigated the associations of age, sex, body size, body composition, and maturity with measures of physical activity (PA) intensity in children. PA intensity was assessed using VO2 as % of VO2reserve or VO2 at ventilatory threshold (VT), muscle activity measured by textile electromyography, mean amplitude deviation (MAD) measured by accelerometry, and metabolic equivalent of task (MET) during laboratory activities.Age, stature, and muscle mass were inversely associated with VO2 as % of VO2reserve and % of VT, during walking or running on a treadmill for 4, 6, and 8 km/h (Spearman r = -0.645 to -0.358). Age was inversely associated with MAD during walking on treadmill for 4 km/h (r = -0.541) and positively associated with MAD during running on a treadmill for 8 km/h, playing hopscotch, and during self-paced running (r = 0.368 to 0.478). Fat mass was positively associated with VO2 as % of VO2reserve and VO2 as % of VO2 at VT and waist circumference was positively associated with VO2 as a % of VO2reserve and muscle activity during stair climbing (r = 0.416 to 0.519).Fixed accelerometry cut-offs used to define PA intensities should be adjusted for age, sex, body size, and body composition.


Assuntos
Tamanho Corporal , Exercício Físico/fisiologia , Maturidade Sexual , Acelerometria , Fatores Etários , Limiar Anaeróbio , Composição Corporal , Estatura , Criança , Eletromiografia , Metabolismo Energético , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Consumo de Oxigênio , Fatores Sexuais , Análise e Desempenho de Tarefas
17.
Scand J Med Sci Sports ; 31(5): 1069-1077, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33464638

RESUMO

The purpose of this study was investigate tendon displacement patterns in non-surgically treated patients 14 months after acute Achilles tendon rupture (ATR) and to classify patients into groups based on their Achilles tendon (AT) displacement patterns. Twenty patients were tested. Sagittal images of AT were acquired using B-mode ultrasonography during ramp contractions at a torque level corresponding to 30% of the maximal isometric plantarflexion torque of the uninjured limb. A speckle tracking algorithm was used to track proximal-distal movement of the tendon tissue at 6 antero-posterior locations. Two-way repeated measures ANOVA for peak tendon displacement was performed. K-means clustering was used to classify patients according to AT displacement patterns. The difference in peak relative displacement across locations was larger in the uninjured (1.29 ± 0.87 mm) than the injured limb (0.69 ± 0.68 mm), with a mean difference (95% CI) of 0.60 mm (0.14-1.05 mm, P < .001) between limbs. For the uninjured limb, cluster analysis formed 3 groups, while 2 groups were formed for the injured limb. The three distinct patterns of AT displacement during isometric plantarflexion in the uninjured limb may arise from subject-specific anatomical variations of AT sub-tendons, while the two patterns in the injured limb may reflect differential recovery after ATR with non-surgical treatment. Subject-specific tendon characteristics are a vital determinant of stress distribution across the tendon. Changes in stress distribution may lead to variation in the location and magnitude of peak displacement within the free AT. Quantifying internal tendon displacement patterns after ATR provides new insights into AT recovery.


Assuntos
Tendão do Calcâneo/lesões , Tendão do Calcâneo/fisiopatologia , Contração Isométrica , Ruptura/fisiopatologia , Tendão do Calcâneo/diagnóstico por imagem , Adulto , Algoritmos , Fenômenos Biomecânicos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Ruptura/diagnóstico por imagem , Ruptura/terapia , Torque , Ultrassonografia
18.
J Gerontol A Biol Sci Med Sci ; 76(9): 1587-1590, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-33230535

RESUMO

BACKGROUND: To examine longitudinal changes in physical performance during the menopausal transition and the role of physical activity (PA) in these changes. METHODS: Based on follicle-stimulating hormone levels and bleeding diaries, women (47-55 years) were classified as early (n = 89) and late perimenopausal (n = 143) and followed prospectively until postmenopausal status, with mean duration of 17.5 and 13.8 months, respectively. Physical performance was measured by handgrip force, knee extension torque, vertical jumping height, maximal walking speed, and 6-minute walking distance. Physical activity was self-reported and categorized as inactive, low, medium, and high. Longitudinal associations of menopausal status, physical performance, and related changes with PA level were analyzed using generalized estimation equations adjusted for duration of hormonal therapy. RESULTS: A significant decline over the menopausal transition in handgrip force (-2.1%, 95% CI -3.8 to -0.4), knee extension torque (-2.6%, 95% CI -4.5 to -0.8), and vertical jumping height (-2.6%, 95% CI -4.2 to -1.1) and a significant increase in 6-minute walking distance (2.1%, 95% CI 1.4 to 2.7) were observed in the total sample. A significant interaction of PA by time was observed in handgrip force and in vertical jumping height. High PA women had greater increase in handgrip strength but greater decline in vertical jumping height than medium, low, and inactive women (all p ≤ .001). CONCLUSIONS: Both early and late perimenopausal women show decline in muscle strength and power during the transition to postmenopause. Physical activity seems to influence physical performance during the menopausal transition but understanding the benefits of PA requires interventional studies.


Assuntos
Exercício Físico , Menopausa/fisiologia , Desempenho Físico Funcional , Antropometria , Biomarcadores/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Força da Mão/fisiologia , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Força Muscular/fisiologia , Estudos Prospectivos , Torque , Caminhada/fisiologia
19.
J Exerc Rehabil ; 17(6): 370-378, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35036385

RESUMO

Physical activity is associated with better health in individuals with cerebral palsy (CP). Numerous physical activity interventions have been designed to promote physical activity among youth with CP. No previous studies have explored the factors contributing to the intention to participate and predicting attendance behaviour for these interventions. Using theory of planned behaviour (TPB), this study explored the prediction of physical activity intention and attendance behaviour in a physical activity intervention aiming to promote physical activity in a sample of young individuals with CP. Males with CP aged 9-21 years were asked to complete measures of attitude, subjective norms, perceived behavioural control and, intentions towards a physical activity intervention. Participants had no cognitive impairments to understand and follow instructions, were categorised into Gross Motor Function Classification System I-III, did not receive any specific lower limbs' medical treatment, or did not participate in a strength training program for lower limbs within 6 months before the study. Subjective norms were found to be the only significant predictor of intention, accounting for 83% of variance in intention. Intention and perceived behaviour control were found to be a nonsignificant predictor of attendance behaviour in youth with CP. The results show that TPB is a relevant tool in the prediction of intention towards a physical activity intervention in Finnish youth with CP.

20.
J Electromyogr Kinesiol ; 55: 102474, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32979677

RESUMO

One of the purposes of footwear is to assist locomotion, but some footwear types seem to restrict natural foot motion, which may affect the contribution of ankle plantar flexor muscles to propulsion. This study examined the effects of different footwear conditions on the activity of ankle plantar flexors during walking. Ten healthy habitually shod individuals walked overground in shoes, barefoot and in flip-flops while fine-wire electromyography (EMG) activity was recorded from flexor hallucis longus (FHL), soleus (SOL), and medial and lateral gastrocnemius (MG and LG) muscles. EMG signals were peak-normalised and analysed in the stance phase using Statistical Parametric Mapping (SPM). We found highly individual EMG patterns. Although walking with shoes required higher muscle activity for propulsion than walking barefoot or with flip-flops in most participants, this did not result in statistically significant differences in EMG amplitude between footwear conditions in any muscle (p > 0.05). Time to peak activity showed the lowest coefficient of variation in shod walking (3.5, 7.0, 8.0 and 3.4 for FHL, SOL, MG and LG, respectively). Future studies should clarify the sources and consequences of individual EMG responses to different footwear.


Assuntos
Eletromiografia/métodos , Pé/fisiologia , Músculo Esquelético/fisiologia , Sapatos , Caminhada/fisiologia , Adulto , Articulação do Tornozelo/fisiologia , Feminino , Marcha/fisiologia , Humanos , Masculino , Adulto Jovem
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