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1.
Eur J Appl Physiol ; 122(8): 1915-1928, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35612684

RESUMO

PURPOSE: Caffeine improves cycling time trial (TT) performance; however, it is unknown whether caffeine is ergogenic when competing against other riders. The aim of this study was to investigate whether caffeine improves performance during a 4-km cycling TT when riding against a virtual opponent, and whether it is associated with increased muscle activation and at the expense of greater end-exercise central and peripheral fatigue. METHODS: Using a randomized, crossover, and double-blind design, eleven well-trained cyclists completed a 4-km cycling TT alone without supplementation (CON), or against a virtual opponent after ingestion of placebo (OP-PLA) or caffeine (5 mg.kg-1, OP-CAF). Central and peripheral fatigue were quantified via the pre- to post-exercise decrease in voluntary activation and potentiated twitch force, respectively. Muscle activation was continually measured during the trial via electromyography activity. RESULTS: Compared to CON, OP-PLA improved 4-km cycling TT performance (P = 0.018), and OP-CAF further improved performance when compared to OP-PLA (P = 0.050). Muscle activation was higher in OP-PLA and OP-CAF than in CON throughout the trial (P = 0.003). The pre- to post-exercise reductions in voluntary activation and potentiated twitch force were, however, similar between experimental conditions (P > 0.05). Compared to CON, OP-PLA increased the rating of perceived exertion during the first 2 km, but caffeine blunted this increase with no difference between the OP-CAF and CON conditions. CONCLUSIONS: Caffeine is ergogenic when riding against a virtual opponent, but this is not due to greater muscle activation or at the expense of greater end-exercise central or peripheral fatigue.


Assuntos
Desempenho Atlético , Substâncias para Melhoria do Desempenho , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Cafeína/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Ingestão de Alimentos , Humanos , Masculino , Fadiga Muscular , Substâncias para Melhoria do Desempenho/farmacologia , Poliésteres
2.
Gerontology ; 67(5): 532-543, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33677447

RESUMO

INTRODUCTION: It is believed that functional capacity and fall history are factors capable of influencing the gait parameters of older adults. Thus, the objective of this study was to verify whether gait parameters of community-dwelling older adults differ according to their functional capacity and fall history when walking at self-selected walking speed (SSWS) and fast walking speed (FWS) using principal component analysis (PCA). METHODS: Two hundred ninety-five participants (82.3% women and 17.7% men) were allocated in four groups according to their fall history and functional capacity: non-fallers with higher functional capacity (NFHFC, n = 94; 69.3 ± 5.5 years), non-fallers with lower functional capacity (NFLFC, n = 114; 72.0 ± 8.1 years), fallers with higher functional capacity (FHFC, n = 29; 70.0 ± 6.0 years), and fallers with lower functional capacity (FLFC, n = 58; 72.5 ± 8.2 years). Fall history, anthropometric data, functional capacity by short physical performance battery and mobility by Timed Up and Go (TUG), and spatiotemporal gait parameters were evaluated. RESULTS: Data analysis indicated that FLFC presented the lowest scores, especially in the Five Times Sit-to-Stand Test and TUG. The PCA showed that the first principal component (PC1) explained the most substantial amount of the data variability in both walking speeds (SSWS and FWS), predominantly including temporal parameters. PC2 composed by spatial outcomes (stride and step length and walking speed) showed the highest effect size. PC1 and PC2 were able to differentiate functional status, regardless of fall history. CONCLUSIONS: Functional capacity showed great importance when analyzing gait parameters at different walking speeds (SSWS and FWS), regardless of fall history. Older adults with high functional capacity demonstrate better performance during gait. Besides, spatiotemporal parameters are the main factors explaining gait variability, both in SSWS and FWS.


Assuntos
Marcha , Caminhada , Acidentes por Quedas , Idoso , Feminino , Humanos , Vida Independente , Masculino , Velocidade de Caminhada
3.
Exp Aging Res ; 47(2): 192-202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33423605

RESUMO

Aim: The aim of this cross-sectional study was to determine which functional tests are able to predict falls in nursing home residents (NHR) and community-dwelling (CDW) older adults grouped by age. Methods: Two hundred and fifty-two older adults were assessed in the following tests, Mini-Mental State Examination, anthropometric characteristics, fall history and functional tests. The participants were assigned to one of the following groups: Young Older Adults (YOA; 60-69 years, n = 102; 27.5% NHR), Old Older Adults (OOA; 70-79 years; n = 100; 23.5% NHR) and Very Older Adults (VOA, ≥80 years; n = 50; 52% NHR). Results: The five times sit-to-stand showed 1.41 odds to experience a fall in the NHR of the VOA. In the CDW, the handgrip strength score decreased the odds to fall occurrence (0.92 odds) in the YOA, while the low score in timed up and go test of the OOA showed 1.21 odds to experience a fall. Conclusions: Therefore, the five times sit-to-stand test can predict falls in NHR of VOA groups, while handgrip strength and timed up and go tests can predict falls in CDW of YOA and OOA groups, respectively.


Assuntos
Vida Independente , Equilíbrio Postural , Idoso , Envelhecimento , Estudos Transversais , Avaliação Geriátrica , Força da Mão , Humanos , Casas de Saúde , Estudos de Tempo e Movimento
4.
Exp Aging Res ; 44(5): 397-410, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30273111

RESUMO

BACKGROUND: Dependence in self-care activities among older women has been previously evaluated through performance-based tests. However, these tests have presented inability to accurately distinguish between dependent and independent older adults in performing activities of daily living. AIM: To examine the validity, reliability, and diagnostic accuracy of rating of perceived exertion (RPE) to identify dependence in performing self-care activities in older women. METHODS: Thirty-five older women performed two different constant-load tasks (walking on treadmill at 4 km/h for five minutes and arm curls with two kg for one minute), reporting RPE at the end, in four sessions. Performance-based tests (30-second chair stand and 6-minute walk) were also evaluated. Katz Index and Lawton and Brody questionnaires were applied to evaluate the dependence level in performing basic and instrumental activities of daily living. RESULTS: RPE was greater on the first session (RPE 14 ± 2) than second session (RPE 13 ± 2), while it was similar through other sessions, with high values of intraclass coefficient correlation (0.96-0.99). Basic activities of daily living and instrumental activities of daily living presented high correlations with RPE measures (0.75-0.82), whereas performance-based tests presented moderate correlations (0.47-0.59). RPE responses explained the most variance in identifying dependence in self-care activities and presented high diagnostic accuracy to differentiate dependent from independent older women. So the hypotheses had been confirmed that RPE responses in constant-load exercise are better predictors of dependence in self-care activities than performance-based tests. CONCLUSIONS: RPE of constant-load physical tasks was valid, reliable, and accurate in identifying dependence in performing self-care activities in older women; therefore, it is possible to use the perceived exertion to identify dependence in performing activities of daily living in older women.


Assuntos
Atividades Cotidianas , Envelhecimento/fisiologia , Avaliação da Deficiência , Esforço Físico/fisiologia , Autocuidado , Idoso , Feminino , Humanos , Reprodutibilidade dos Testes
5.
J Sports Sci Med ; 16(4): 574-580, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29238259

RESUMO

The aims of this study were to investigate whether land-based and tethered swimming strength tests can explain swimming performance in 200-meter front crawl and, whether these tests were able to identify bilateral symmetry in force production. In the first session, eighteen swimmers completed a maximum effort 200 m front crawl swim (swimming performance) and 15 seconds maximal effort tethered front crawl swim. In the second session, participants performed the upper extremity isometric strength test. Peak force production of tethered swimming and isometric strength tests were significantly correlated for the strongest and weakest sides (r = 0.58 and r = 0.63, respectively; p < 0.05), but only peak force production during tethered swimming correlated with 200 m swimming performance time (r = -0.55, p < 0.05). Bilateral asymmetries in peak force and rate of force development were similar between the tethered swimming and isometric strength tests (peak force: 13%, p = 0.24; rate of force development: 15%, p = 0.88) However, both tests detected significant difference of peak force and rate of force development between body sides. The tethered swimming test can partially explain the 200 m front crawl swimming performance. In addition, the land-based and tethered swimming tests may be used to identify bilateral asymmetry of swimming.

6.
J Strength Cond Res ; 30(9): 2500-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24531436

RESUMO

Santos, KB, Bento, PCB, Pereira, G, and Rodacki, ALF. The relationship between propulsive force in tethered swimming and 200-m front crawl performance. J Strength Cond Res 30(9): 2500-2507, 2016-The aims of this study were to determine whether propulsive force (peak force, mean force, impulse, and rate of force development) and stroke rate change during 2 minutes of front crawl tethered swimming and to correlate them with the stroke rate and swimming velocity in 200-m front crawl swimming. Twenty-one swimmers (21.6 ± 4.8 years, 1.78 ± 0.06 m, 71.7 ± 8.1 kg), with 200-m front crawl swimming performance equivalent to 78% of the world record (140.4 ± 10.1 seconds), were assessed during 2 minutes of maximal front crawl tethered swimming (propulsive forces and stroke rate) and 200-m front crawl swimming (stroke rate and clean velocity). Propulsive forces decreased between the beginning and the middle instants (∼20%; p ≤ 0.05) but remained stable between the middle and the end instants (∼6%; p > 0.05). The peak force was positively correlated with the clean velocity in the 200-m front crawl swimming (mean r = 0.61; p < 0.02). The stroke rates of the tethered swimming and 200-m front crawl swimming were positively correlated (r = 45; p≤ 0.01) at the middle instant. Therefore, the propulsive force and stroke rate changed throughout the 2 minutes of tethered swimming, and the peak force is the best propulsive force variable tested that correlated with 200-m front crawl swimming performance.


Assuntos
Desempenho Atlético/fisiologia , Natação/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos/fisiologia , Humanos , Adulto Jovem
7.
J Strength Cond Res ; 30(9): 2392-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24531431

RESUMO

Rebutini, VZ, Pereira, G, Bohrer, RCD, Ugrinowitsch, C, and Rodacki, ALF. Plyometric long jump training with progressive loading improves kinetic and kinematic swimming start parameters. J Strength Cond Res 30(9): 2392-2398, 2016-This study was aimed to determine the effects of a plyometric long jump training program on torque around the lower limb joints and kinetic and kinematics parameters during the swimming jump start. Ten swimmers performed 3 identical assessment sessions, measuring hip and knee muscle extensors during maximal voluntary isometric contraction and kinetic and kinematics parameters during the swimming jump start, at 3 instants: INI (2 weeks before the training program, control period), PRE (2 weeks after INI measurements), and POST (24-48 hours after 9 weeks of training). There were no significant changes from INI to PRE measurements. However, the peak torque and rate of torque development increased significantly from PRE to POST measurements for both hip (47 and 108%) and knee (24 and 41%) joints. There were significant improvements to the horizontal force (7%), impulse (9%), and angle of resultant force (19%). In addition, there were significant improvements to the center of mass displacement (5%), horizontal takeoff velocity (16%), horizontal velocity at water entrance (22%), and peak angle velocity for the knee (15%) and hip joints (16%). Therefore, the plyometric long jump training protocol was effective to enhance torque around the lower limb joints and to control the resultant vector direction, to increase the swimming jump start performance. These findings suggest that coaches should use long jump training instead of vertical jump training to improve swimming start performance.


Assuntos
Fenômenos Biomecânicos/fisiologia , Contração Isométrica/fisiologia , Extremidade Inferior/fisiologia , Músculo Esquelético/fisiologia , Exercício Pliométrico/métodos , Natação/fisiologia , Adulto , Teste de Esforço , Feminino , Humanos , Cinética , Masculino , Avaliação de Programas e Projetos de Saúde , Torque , Adulto Jovem
8.
Percept Mot Skills ; 119(3): 884-900, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25387039

RESUMO

This study developed a Color Scale of Perceived Exertion (RPE-color scale) and assessed its concurrent and construct validity in adult women. One hundred participants (18-77 years), who were habitual exercisers, associated colors with verbal anchors of the Borg RPE scale (RPE-Borg scale) for RPE-color scale development. For RPE-color scale validation, 12 Young (M = 21.7 yr., SD = 1.5) and 10 Older (M = 60.3 yr., SD = 3.5) adult women performed a maximal graded exercise test on a treadmill and reported perceived exertion in both RPE-color and RPE-Borg scales. In the Young group, the RPE-color scale was significantly associated with heart rate and oxygen consumption, having strong correlations with the RPE-Borg scale. In the Older group, the RPE-color scale was significantly associated with heart rate, having moderate to high correlations with the RPE-Borg scale. The RPE-color scale demonstrated concurrent and construct validity in the Young women, as well as construct validity in Older adults.


Assuntos
Teste de Esforço/psicologia , Percepção/fisiologia , Esforço Físico/fisiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Brasil , Cor , Teste de Esforço/métodos , Teste de Esforço/estatística & dados numéricos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Psicometria , Adulto Jovem
9.
Arch Gerontol Geriatr ; 125: 105489, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38851093

RESUMO

The meta-analysis aimed to determine whether exercise training can positively change indices of motor drive, i.e., the input from the central nervous system to the muscle, and how training characteristics, motor drive assessment, assessed muscle, and testing specificity could modulate the changes in motor drive in older adults. A random-effect meta-analysis model using standardized mean differences (Hedges' g) determined treatment effects. Moderators (e.g., training type and intensity) and meta-regressors (e.g., number of sessions) were performed using mixed- and fixed-effect models. A significant Q-test, followed by pairwise post hoc comparisons, determined differences between levels of the categorical moderators. Methodological quality was assessed using the Cochrane risk of bias tool. Ten randomized controlled trials, 290 older adults, met the inclusion criteria. Only strength and power exercise training were retrieved from the search and included in the analysis. Strength (g = 0.60, 95 % CI 0.24 to 0.96) and power training (g = 0.51, 95 % CI 0.02 to 1.00) increased motor drive compared with a control condition. High (g = 0.66; 95 % CI 0.34 to 0.97) and low-high (g = 1.23; 95 % CI 0.19 to 2.27) combinations of training intensities increased motor drive compared to the control condition. The multi-joint training and testing exercise structure (g = 1.23; 95 % CI 0.79 to 1.67) was more effective in increasing motor drive (Qdf=2 = 14.15; p = 0.001) than the multi-single joint structure (g = 0.46; 95 % CI 0.06 to 0.85). Therefore, strength and power training with high volume and intensity associated with multi-joint training and testing combination of exercises seem to improve skeletal muscle motor drive in older adults effectively.


Assuntos
Músculo Esquelético , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Idoso , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Força Muscular/fisiologia , Exercício Físico/fisiologia , Terapia por Exercício/métodos
10.
Med Sci Sports Exerc ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38768034

RESUMO

PURPOSE: To compare the development of fatigability during a moderate intensity cycling exercise between women with fibromyalgia (FM) and control women (CON) after acute ingestion of caffeine and placebo. METHODS: Ten FM and 10 CON women performed a 30-minute moderate intensity cycling exercise one hour after the ingestion of a capsule containing either caffeine or a placebo. Fatigability and its central and peripheral determinants were determined via changes from pre- to post-15 and post-30 minutes of exercise in maximal voluntary isometric contractions (MVIC), voluntary activation (VA), and quadriceps potentiated twitch torque (Q tw-pot ), respectively. Heart rate, muscle oxygen saturation, perceptive responses, mood state, localized and widespread pain, and sleepiness were also monitored during and after exercise. RESULTS: There was a time vs. group interaction for MVIC and VA (p < 0.001) but not for Q tw-pot (p = 0.363), indicating a greater rate of fatigability development, mainly caused by central mechanisms, in the FM than in the CON group. There was also a main effect of condition for VA (p = 0.011), indicating that caffeine attenuates central mechanisms of fatigability in both groups. Caffeine ingestion also increased muscle oxygenation, perceived vigor, and energy, and decreased leg muscle pain, sleepiness, and perceived fatigue in both groups. However, caffeine improved perceived pleasure/displeasure and exercise adherence likelihood only in the FM group. CONCLUSIONS: Compared to CON, women with FM present a greater rate of fatigability during exercise, mainly of central origin. Caffeine seems to be a promising bioactive to counteract the central mechanisms of fatigability and improve the exercise experience among FM women.

11.
Curr Aging Sci ; 16(2): 125-132, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36214305

RESUMO

BACKGROUND: Nursing home residents are likely to differ from community older adults when their gait parameters are compared, as nursing home residents present more falls. AIM: The study aim was to identify the main fall (occurrence predictors) (anthropometrics, functional and gait-related parameters) between older adults living in community and nursing homes during self-selected (SSWS) and fast walking speeds (FWS). METHODS: A hundred and sixty-five older adults were selected from the community (n = 92) and nursing home (n = 73) with and without fall history. They were assessed for fall history, functionality, cognitive status, and several gait parameters in SSWS and FWS conditions. RESULTS: Fallers differed from non-fallers in the SSWS, while such differences were not evidenced during the FWS. Cadence and stride width did not differ when living backgrounds were compared. Nursing home residents walked slower than their non-institutionalized peers, regardless of fall history or walking speed. Besides, binary logistic regression analysis showed that living in a nursing home, age, body mass index (BMI), mini-mental state examination (MMSE), and step width were related to falls in the SSWS. On the other hand, living in a nursing home, having a larger BMI and having low MMSE scores were fall predictors in the FWS. CONCLUSION: Fall occurrence can be identified by factors related to living in nursing homes, cognitive status, BMI, and gait parameters, at the SSWS. Cognitive status and BMI are related to falls in the FWS for those living in nursing homes.


Assuntos
Acidentes por Quedas , Sobrepeso , Humanos , Idoso , Estudos Transversais , Marcha , Casas de Saúde , Cognição
12.
Eur J Sport Sci ; 23(6): 885-895, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35502595

RESUMO

This study compared central and peripheral fatigue development between the Sprint and Olympic distance triathlon. Fifteen male triathletes performed Sprint and Olympic triathlon simulations in a randomized and counterbalanced order. Central and peripheral fatigue was evaluated from changes in voluntary activation level (VAL) and twitch responses of quadriceps muscle (Qtw,pot), respectively. Qtw,pot reduced from baseline to post-swimming similarly between triathlon simulations (Sprint,-17±11%; Olympic, -13±9%). In post-cycling, Qtw,pot further declined to a similar extent between triathlon distances (Sprint, -31±15%; Olympic, -28±11%). In post-running, Qtw,pot was fully recovered in the Olympic triathlon (-4±10%), whereas there was only a partial recovery of Qtw,pot in the Sprint triathlon (-20±11%). VAL was not reduced in post-swimming, but reduction was similar between triathlon distances in post-cycling (Sprint, -10±9%; Olympic, -8±8%) and post-running (Sprint, -15±14%; Olympic, -16±8%). In the Sprint triathlon, the swimming speed (1.07±0.13m.s-1) was above (p <.001) critical speed (1.01±0.14m.s-1), the cycling power (179.7±27.2W) was below the respiratory compensation point (216.3±27.8W, p <.001) and running speed (13.7±1.05km.h-1) similar to the respiratory compensation point (13.2±0.70km.h-1, p =.124). In the Olympic triathlon, swimming speed (1.03±0.13m.s-1) was similar to critical speed (p =.392), and cycling power (165.3±27.3W) and running speed (12.6±1.05km.h-1) were below the respiratory compensation point (p ≤.007). In conclusion, peripheral fatigue progressed until post-cycling regardless of triathlon distances. However, peripheral fatigue was fully recovered after running in Olympic but not in Sprint triathlon. The central fatigue started in post-cycling and progressed until post-running regardless of triathlon distances.HighlightsThe quadriceps muscle peripheral fatigue progresses similarly in Sprint and Olympic triathlons until post-cycling.The quadriceps muscle peripheral fatigue is completely recovered after running in the Olympic triathlon, whereas it is partially recovered in the Sprint triathlon.The central fatigue starts in post-cycling and progresses similarly until post-running in Sprint and Olympic triathlons, regardless of triathlon distances.


Assuntos
Músculo Quadríceps , Corrida , Humanos , Masculino , Corrida/fisiologia , Natação/fisiologia , Ciclismo/fisiologia , Fatores de Tempo
13.
J Aging Phys Act ; 20(4): 469-83, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22714953

RESUMO

OBJECTIVE: To analyze the effects of a water-based exercise program on peak torque (PT) and rate of torque development (RTD) during maximal voluntary ballistic isometric contractions of the lower limb muscles and the performance of a number of functional tests in the elderly. METHOD: Thirty-seven elderly were randomly assigned to water-based training (3 d/wk for 12 wk) or a control group. Extensor and flexor PT and RTD of the ankle, knee, and hip joints and functional tests were evaluated before and after training. RESULTS: PT increased after training for the hip flexors (18%) and extensors (40%) and the plantar-flexor (42%) muscles in the water-based group. RTD increased after training for the hip-extensor (10%), knee-extensor (11%), and ankle plantar-flexor (27%) muscles in the water-based group. Functional tests also improved after training in the water-based group (p < .05). CONCLUSION: The water-based program improved PT and RTD and functional performance in the elderly.


Assuntos
Envelhecimento/fisiologia , Hidroterapia/métodos , Contração Isométrica/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Avaliação de Programas e Projetos de Saúde , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Teste de Esforço , Feminino , Humanos , Extremidade Inferior/fisiologia , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Torque
14.
J Strength Cond Res ; 26(12): 3335-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22222321

RESUMO

This study aimed at comparing the effects of strength and power training (ST and PT) regimens on neuromuscular adaptations and changes on vertical jump performance, kinetics, and kinematics parameters. Forty physically active men (178.2 ± 7.0 cm; 75.1 ± 8.6 kg; 23.6 ± 3.5 years) with at least 2 years of ST experience were assigned to an ST (n = 14), a PT (n = 14), or a control group (C; n = 12). The training programs were performed during 8 weeks, 3 times per week. Dynamic and isometric maximum strength, cross-sectional area, and muscle activation were assessed before and after the experimental period. Squat jump (SJ) and countermovement jump (CMJ) performance, kinetics, and kinematics parameters were also assessed. Dynamic maximum strength increased similarly (p < 0.05) for the ST (22.8%) and PT (16.6%) groups. The maximum voluntary isometric contraction increased for the ST and PT groups (p < 0.05) in the posttraining assessments. There was a main time effect for muscle fiber cross-sectional area (p < 0.05), but there were no changes in muscle activation. The SJ height increased, after ST and PT, because of a faster concentric phase and a higher rate of force development (p < 0.05). The CMJ height increased only after PT (p < 0.05), but there were no significant changes in its kinetics and kinematics parameters. In conclusion, neuromuscular adaptations were similar between the training groups. The PT seemed more effective than the ST in increasing jumping performance, but neither the ST nor the PT was able to affect the SJ and the CMJ movement pattern (e.g., timing and sequencing of joint extension initiation).


Assuntos
Adaptação Fisiológica , Contração Isométrica/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Biópsia , Eletromiografia , Humanos , Masculino , Movimento/fisiologia , Estatísticas não Paramétricas , Gravação em Vídeo , Adulto Jovem
15.
Percept Mot Skills ; 129(4): 1053-1073, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35465772

RESUMO

This study investigated the extent to which mental fatigue and emotional suppression affected exercise endurance. Twelve participants performed cycling endurance tests at 80% of their peak power up to the point of exhaustion. Two experimental conditions (mental fatigue [MF] and emotion suppression conditions [ES]) and a control condition (CO) were administered. Participants responded to psychological measures throughout the exercise trials. Both MF and ES conditions hindered exercise performance relative to the CO, and there was no statistically significant difference between the negative effects of both MF and ES conditions. Of note, however, higher levels of subjective fatigue were reported in MF, prior to commencing the exercise test. High cognitive loads that induce MF and/or engaging in ES may reduce high intensity endurance exercise performance among young adults, but further research with greater numbers of participants is needed to replicate and extend these findings.


Assuntos
Fadiga Mental , Resistência Física , Emoções , Exercício Físico , Teste de Esforço , Humanos , Adulto Jovem
16.
J Sports Sci ; 29(9): 927-32, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21547835

RESUMO

The aims of this study were (a) to assess the ability of the rating of perceived exertion (RPE) to predict performance (i.e. number of vertical jumps performed to a fixed jump height) of an intermittent vertical jump exercise, and (b) to determine the ability of RPE to describe the physiological demand of such exercise. Eight healthy men performed intermittent vertical jumps with rest periods of 4, 5, and 6 s until fatigue. Heart rate and RPE were recorded every five jumps throughout the sessions. The number of vertical jumps performed was also recorded. Random coefficient growth curve analysis identified relationships between the number of vertical jumps and both RPE and heart rate for which there were similar slopes. In addition, there were no differences between individual slopes and the mean slope for either RPE or heart rate. Moreover, RPE and number of jumps were highly correlated throughout all sessions (r = 0.97-0.99; P < 0.001), as were RPE and heart rate (r = 0.93-0.97; P < 0.001). The findings suggest that RPE can both predict the performance of intermittent vertical jump exercise and describe the physiological demands of such exercise.


Assuntos
Exercício Físico/psicologia , Frequência Cardíaca , Resistência Física , Esforço Físico/fisiologia , Adolescente , Adulto , Exercício Físico/fisiologia , Teste de Esforço , Fadiga , Humanos , Masculino , Movimento , Percepção , Descanso , Análise e Desempenho de Tarefas , Adulto Jovem
17.
J Strength Cond Res ; 25(7): 2053-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21606860

RESUMO

The aim of this study was to compare the power outputs of the intermittent critical power (CPi) with the intermittent maximal lactate steady state (MLSSi) and to compare the physiological and perceptual responses exercising at CPi and MLSSi. Ten subjects performed intermittent trials on a cycle ergometer to determine CPi and MLSSi using 30:30 seconds of effort and pause. The oxygen uptake (&OV0312;o2), heart rate (HR), blood lactate concentration ([Lac]), and rating of perceived exertion (RPE) responses were compared during 30-minute cycling at CPi and MLSSi. The CPi (267 ± 45 W) was similar to MLSSi (254 ± 39 W), and they were correlated (r = 0.88; p < 0.05). The &OV0312;o2 and HR responses stabilized throughout exercising at CPi (2.52 ± 0.52 L·min; 156 ± 8 b·min) and MLSSi (2.41 ± 0.32 L·min; 152 ± 10 b·min). These physiological variables were similar between conditions. However, the [Lac] and RPE were higher from the middle to the end of exercise duration at CPi ([Lac] = 6.9 ± 2.6 mM; RPE = 17.1 ± 2.1 a.u.) compared to MLSSi ([Lac] = 5.1 ± 0.9 mM; RPE = 15.7 ± 1.8 a.u.). Therefore, CPi intensity determined from 30:30 seconds of effort and rest periods on a cycle ergometer is equivalent to the MLSSi, and there is a physiological steady state throughout both exercise intensities, although the [Lac] and RPE responses at CPi are higher than at MLSSi. Thus, the CPi and MLSSi may be used as tools for intermittent training evaluation and prescription.


Assuntos
Teste de Esforço/métodos , Ácido Láctico/sangue , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Esforço Físico/fisiologia , Adulto , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Percepção , Fatores de Tempo , Adulto Jovem
18.
J Strength Cond Res ; 24(6): 1602-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20508465

RESUMO

This study aimed to determine if the OMNI scale with cycle ergometer pictorial format can be used to estimate perceived exertion threshold (PETOMNI) and nonexhaustive PET (PETOMNI5-8) and to compare and to correlate these PET estimates with PETBorg, PETBorg14-17, and critical power (CP). During different days, 13 men performed 4 different high-intensity constant-loads work bouts until exhaustion on a cycle ergometer using the Borg scale, whereas the OMNI scale was used during the other 4 work bouts using previous constant loads. The PET for both scales was determined by plotting the increasing rates of perceived exertion against power outputs, PET being the intersection point of the regression line. In addition, a hyperbolic relationship between power and time to exhaustion was used to determine CP. The PETOMNI (183+/-36 W) was similar to PETBorg (178+/-46 W), and they were also significantly correlated (r=0.77). The PETOMNI5-8 (175+/-36 W) was similar to PETBorg14-17 (181+/-38 W); however, they were not significantly correlated (r=0.36). All the PET estimates were similar to CPOMNI (167+/-36 W) and CPBorg (169+/-40 W) and also significantly correlated (r=0.79-0.94), excepting PETOMNI5-8 (r=0.46). In conclusion, OMNI cycling scale can be used to estimate PET and CP with high accuracy. However, the nonexhaustive PET derived from the 5-8 range in the OMNI scale did not provide a valid estimate of maximal sustainable power output because of the absence of correlation with PETBorg14-17 and with CP. Therefore, professionals and practitioners can assess the subjects' aerobic fitness through the PET estimation using the OMNI scale during exhaustive tests.


Assuntos
Teste de Esforço/métodos , Esforço Físico/fisiologia , Adulto , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Percepção/fisiologia , Resistência Física/fisiologia , Adulto Jovem
19.
Percept Mot Skills ; 110(1): 257-64, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20391890

RESUMO

The aim of this study was to investigate the effects of preferred and nonpreferred music on exercise distance, Heart Rate (HR), and Rating of Perceived Exertion (RPE) during continuous cycling exercise performed at high intensity. Fifteen participants performed five test sessions. During two sessions, they cycled with fixed workload on ergometer to determine the Critical Power (CP) intensity. Then, they performed three more sessions cycling at CP intensity: listening to Preferred Music, listening to Nonpreferred Music, and No Music. The HR responses in the exercise sessions did not differ among all conditions. However, the RPE was higher for Nonpreferred Music than in the other conditions. The performance under Preferred Music (9.8 +/- 4.6 km) was greater than under Nonpreferred Music (7.1 +/- 3.5 km) conditions. Therefore, listening to Preferred Music during continuous cycling exercise at high intensity can increase the exercise distance, and individuals listening to Nonpreferred Music can perceive more discomfort caused by the exercise.


Assuntos
Desempenho Atlético , Percepção Auditiva , Comportamento de Escolha , Teste de Esforço/psicologia , Música , Atenção , Conscientização , Frequência Cardíaca , Humanos , Julgamento , Masculino , Motivação , Esforço Físico , Adulto Jovem
20.
J Aging Res ; 2020: 6345753, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014466

RESUMO

OBJECTIVE: The aim of this study was to compare the effects of multicomponent and strength training programs on dynamic balance, functional capacity, and gait ability in older women. METHODS: Thirty individuals (67 ± 4.3 years; 30.6 ± 3.9 kg/m2) were trained for 12 weeks (3 times per week), following multicomponent (MG: exercises focusing on agility, balance, muscle strength, and aerobic) and strength programs (SG: lower limbs strength exercise). RESULTS: Peak torque of hip flexors (p=0.020) and extensors (p=0.009) and knee flexors (p=0.001) of SG was greater than that of MG at posttraining. In addition, both groups increased peak torque of knee extensors (p=0.002) and plantar extensors with higher effect size for SG (d = -0.41 and -0.48), whereas MG presented higher effect size for plantar flexors muscles (d = -0.55). Only the SG improved the rate of torque development of knee extensors (29%; p=0.002), and this variable was also greater to SG than MG at posttraining (106%). The SG and MG improved dynamic balance although SG presented higher effect size (d = 0.61). Both groups improved the performance on 30 s sit to stand test (p=0.010) with higher effect size for MG (d = -0.54). Only the MG improved the stride length (4%; p=0.011) and gait speed (10%; p=0.024). In addition, the groups improved toe clearance (p=0.035) and heel contact (p=0.010) with higher effect sizes for MG (d = -0.066 and 1.07). CONCLUSION: Strength training should be considered to increase muscle function and dynamic balance in older women, whereas multicomponent training should be considered to increase functional capacity and gait ability in this population.

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