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1.
J Sci Med Sport ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38839539

RESUMO

We quantified and compared the mechanical force demands relative to the maximum dynamic force (MDF) of 11 cyclists when pedaling at different intensities (ventilatory threshold, maximum lactate steady state, respiratory compensation point, and maximal aerobic power), cadences (free, 40, 60 and 80 rpm), and all-out resisted sprints. Relative force demands (expressed as %MDF) progressively increased with higher intensities (p < 0.001) and lower cadences (p < 0.001). Notwithstanding, relative force demands were low (<54 % MDF) for all conditions, even during the so-called 'torque training'. These results might be useful when programming on-bike resistance training to improve torque production capacity.

2.
J Nutr Health Aging ; 28(5): 100208, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38489992

RESUMO

OBJECTIVES: To investigate the synergist effects of exercise and ß-hydroxy ß-methylbutyrate (HMB) supplementation on disability, cognitive and physical function, and muscle power in institutionalized older people. DESIGN: Cluster-randomized controlled trial. PARTICIPANTS: Seventy-two institutionalized older adults (age = 83 ± 10 years old; 63% women) were randomized in four groups: exercise plus placebo (EX), HMB supplementation, EX plus HMB supplementation (EX + HMB), and control (CT). INTERVENTION: The exercising participants completed a 12-week tailored multicomponent exercise intervention (Vivifrail; 5 days/week of an individualized resistance, cardiovascular, balance and flexibility program), whereas the HMB groups received a drink containing 3 g/day of HMB. MEASUREMENTS: Participants were assessed Pre and Post intervention for disability and cognitive function (validated questionnaires), physical function (short physical performance battery, SPPB), handgrip strength and sit-to-stand relative muscle power. Linear mixed-effect models were used to compare changes among groups. RESULTS: Compared to baseline, both EX and EX + HMB improved cognitive function (+2.9 and +1.9 points; p < 0.001), SPPB score (+2.9 points and +2.4 points; p < 0.001) and relative muscle power (+0.64 and +0.48 W·kg-1; p < 0.001), while CT and HMB remained unchanged (p > 0.05). Significant between-group differences were noted between CT, EX and EX + HMB for cognitive function (p < 0.01), between CT and EX + HMB for physical function (p = 0.043), and between CT, EX and EX + HMB for relative muscle power (p < 0.001). CONCLUSION: The Vivifrail exercise program was effective in improving cognitive and physical function, and muscle power in nursing home residents, while HMB supplementation did not provide additional benefits when combined with exercise. These results emphasize the importance of physical exercise interventions in very old people as an essential basis for improving their overall health and quality of life.


Assuntos
Cognição , Suplementos Nutricionais , Valeratos , Humanos , Feminino , Masculino , Valeratos/administração & dosagem , Valeratos/farmacologia , Cognição/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Força Muscular/efeitos dos fármacos , Força da Mão , Pessoas com Deficiência , Terapia por Exercício/métodos , Exercício Físico/fisiologia
3.
Sensors (Basel) ; 24(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38544265

RESUMO

We aimed to determine the feasibility, test-retest reliability and long-term stability of a novel method for assessing the force (torque)-velocity (cadence) profile and maximal dynamic force (MDF) during leg-pedaling using a friction-loaded isoinertial cycle ergometer and a high-precision power-meter device. Fifty-two trained male cyclists completed a progressive loading test up to the one-repetition maximum (1RM) on a cycle ergometer. The MDF was defined as the force attained at the cycle performed with the 1RM-load. To examine the test-retest reliability and long-term stability of torque-cadence values, the progressive test was repeated after 72 h and also after 10 weeks of aerobic and strength training. The participants' MDF averaged 13.4 ± 1.3 N·kg-1, which was attained with an average pedal cadence of 21 ± 3 rpm. Participants' highest power output value was attained with a cadence of 110 ± 16 rpm (52 ± 5% MDF). The relationship between the MDF and cadence proved to be very strong (R2 = 0.978) and independent of the cyclists' MDF (p = 0.66). Cadence values derived from this relationship revealed a very high test-retest repeatability (mean SEM = 4 rpm, 3.3%) and long-term stability (SEM = 3 rpm, 2.3%); despite increases in the MDF following the 10-week period. Our findings support the validity, reliability and long-term stability of this method for the assessment of the torque-cadence profile and MDF in cyclists.


Assuntos
Ciclismo , Ergometria , Humanos , Masculino , Torque , Reprodutibilidade dos Testes , , Teste de Esforço/métodos
4.
Int J Sports Med ; 45(2): 110-115, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37956877

RESUMO

We examined the effect of breast cancer surgery and adjuvant therapy on the relationship between bar velocity and relative intensity (load-velocity [L-V] relationship) of the bench press (BP) exercise. Twenty-two breast cancer survivors (age: 48.0±8.2 yr., relative strength: 0.40±0.08) completed a loading test up to the one-repetition maximum (1RM) in the BP using a lightweight carbon bar. General and individual relationships between relative intensity (%1RM) and mean propulsive velocity (MPV) were studied. Furthermore, the mean test velocity (MPVTest) and velocity attained to the 1RM (MPV1RM) were analyzed. These procedures and analyses were also conducted in 22 healthy women (age: 47.8±7.1 yr., relative strength: 0.41±0.09) to examine the differences in velocity parameters derived from these L-V relationships. Polynomial regressions showed very close relationships (R2≥0.965) and reduced estimation errors (≤4.9% 1RM) for both groups. Between-group differences in MPV attained to each %1RM were small (≤0.01 m·s-1) and not significant (p≥0.685). Similarly, the MPVTest (0.59±0.06 m·s-1) and MPV1RM (0.17±0.03 m·s-1) were identical for breast cancer survivors and healthy women. These results suggest that practitioners could use the same velocity parameters derived from the BP L-V relationship to prescribe this exercise in middle-aged women, regardless of whether they have suffered from breast cancer.


Assuntos
Neoplasias da Mama , Treinamento Resistido , Pessoa de Meia-Idade , Humanos , Feminino , Adulto , Neoplasias da Mama/cirurgia , Treinamento Resistido/métodos , Levantamento de Peso , Força Muscular , Exercício Físico , Terapia por Exercício
5.
Med Sci Sports Exerc ; 55(12): 2316-2327, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37535335

RESUMO

PURPOSE: This study aimed to compare the effects of free-weight and machine-based resistance training on strength, hypertrophy, and joint discomfort. METHODS: Thirty-eight resistance-trained men participated in an 8-wk resistance program allocated into free-weight ( n = 19) or machine-based ( n = 19) groups. Training variables were identical for both modalities, so they only differed in the use of barbells or machines to execute the full squat, bench press, prone bench pull, and shoulder press exercises. The velocity-based method was implemented to accurately adjust the intensity throughout the program. Strength changes were evaluated using eight velocity-monitored loading tests (four exercises × two modalities) and included the relative one-repetition maximum (1RM Rel ), as well as the mean propulsive velocity against low (MPV Low ) and high (MPV High ) loads. Ultrasound-derived cross-sectional area of quadriceps (proximal and distal regions), pectoralis major, and rectus abdominis was measured to examine hypertrophy. Complementarily, Western Ontario and McMaster Universities and Disabilities of the Arm, Shoulder and Hand questionnaires were administrated to assess changes in lower- and upper-limb joint discomfort. Outcomes were compared using ANCOVA and percentage of change (∆) statistics. RESULTS: Each group significantly ( P < 0.001) increased 1RM Rel , MPV Low , and MPV High for both modalities tested, but especially in the one they trained. When considering together the eight exercises tested, strength changes for both modalities were similar (∆ differences ≤1.8%, P ≥ 0.216). Likewise, the cross-sectional area of all the muscles evaluated was significantly increased by both modalities, with no significant differences between them (∆ difference ≤2.0%, P ≥ 0.208). No between-group differences ( P ≥ 0.144) were found for changes in stiffness, pain, and functional disability levels, which were reduced by both modalities. CONCLUSIONS: Free-weight and machine-based modalities are similarly effective to promote strength and hypertrophy without increasing joint discomfort.


Assuntos
Força Muscular , Músculo Quadríceps , Masculino , Humanos , Força Muscular/fisiologia , Postura , Exercício Físico/fisiologia , Hipertrofia
6.
Scand J Med Sci Sports ; 33(10): 1948-1957, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37340878

RESUMO

BACKGROUND: Although the superior effectiveness of free-weight over machine-based training has been a traditionally widespread assumption, longitudinal studies comparing these training modalities were scarce and heterogeneous. OBJECTIVE: This research used the velocity-based method to compare the effects of free-weight and machine-based resistance training on athletic performance and muscle architecture. METHODS: Thirty-four resistance-trained men participated in an 8-week resistance training program allocated into free-weight (n = 17) or machine-based (n = 17) groups. Training variables (intensity, intraset fatigue, and recovery) were identical for both groups, so they only differed in the use of a barbell or specific machines to execute the full squat, bench press, prone bench pull, and shoulder press exercises. The velocity-based method was implemented to accurately adjust the planned intensity. Analysis of covariance and effect size (ES) statistics were used to compare both training modalities on a comprehensive set of athletic and muscle architecture parameters. RESULTS: No between-group differences were found for any athletic (p ≥ 0.146) and muscle architecture (p ≥ 0.184) variable. Both training modalities significantly and similarly improved vertical jump (Free-weight: ES ≥ 0.45, p ≤ 0.001; Machine-based: ES ≥ 0.41, p ≤ 0.001) and lower limb anaerobic capacity (Free-weight: ES ≥ 0.39, p ≤ 0.007; Machine-based: ES ≥ 0.31, p ≤ 0.003). Additionally, the machine-based group meaningfully enhanced upper limb anaerobic power (ES = 0.41, p = 0.021), whereas the free-weight group significantly improved the change of direction (ES = -0.54, p = 0.003) and 2/6 balance conditions analyzed (p ≤ 0.012). Changes in sprint capacity (ES ≥ -0.13, p ≥ 0.274), fascicle length, and pennation angle (ES ≤ 0.19, p ≥ 0.129) were not significant for either training modality. CONCLUSION: Adaptations in athletic performance and muscle architecture would not be meaningfully influenced by the resistance modality trained.


Assuntos
Desempenho Atlético , Músculos , Treinamento Resistido , Humanos , Masculino , Desempenho Atlético/fisiologia , Extremidade Inferior/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Adulto Jovem , Adulto
7.
J Strength Cond Res ; 37(9): e500-e509, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37015023

RESUMO

ABSTRACT: Hernández-Belmonte, A, Buendía-Romero, Á, Pallares, JG, and Martínez-Cava, A. Velocity-based method in free-weight and machine-based training modalities: the degree of freedom matters. J Strength Cond Res 37(9): e500-e509, 2023-This study aimed to analyze and compare the load-velocity relationships of free-weight and machine-based modalities of 4 resistance exercises. Moreover, we examined the influence of the subject's strength level on these load-velocity relationships. Fifty men completed a loading test in the free-weight and machine-based modalities of the bench press, full squat, shoulder press, and prone bench pull exercises. General and individual relationships between relative intensity (%1RM) and velocity variables were studied through the coefficient of determination ( R2 ) and standard error of the estimate ( SEE ). Moreover, the velocity attained to each %1RM was compared between both modalities. Subjects were divided into stronger and weaker to study whether the subject's strength level influences the mean test (mean propulsive velocity [MPV Test ]) and 1RM (MPV 1RM ) velocities. For both modalities, very close relationships ( R2 ≥ 0.95) and reduced estimation errors were found when velocity was analyzed as a dependent ( SEE ≤ 0.086 m·s -1 ) and independent ( SEE ≤ 5.7% 1RM) variable concerning the %1RM. Fits were found to be higher ( R2 ≥ 0.995) for individual load-velocity relationships. Concerning the between-modality comparison, the velocity attained at each intensity (from 30 to 100% 1RM) was significantly faster for the free-weight variant. Finally, nonsignificant differences were found when comparing MPV Test (differences ≤ 0.02 m·s -1 ) and MPV 1RM (differences ≤ 0.01 m·s -1 ) between stronger and weaker subjects. These findings prove the accuracy and stability of the velocity-based method in the free-weight and machine-based variants but highlight the need to use the load-velocity relationship (preferably the individual one) specific to each training modality.


Assuntos
Fragilidade , Treinamento Resistido , Masculino , Humanos , Força Muscular , Treinamento Resistido/métodos , Levantamento de Peso , Terapia por Exercício , Postura
8.
J Appl Physiol (1985) ; 134(1): 95-104, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36476156

RESUMO

The aim of this study was to determine the effectiveness of physical exercise, respiratory muscle training, and the self-management World Health Organization (WHO) recommendations leaflet on the recovery of physical fitness, quality of life, and symptom status in people with post-COVID-19 conditions. Eighty nonhospitalized adults with a post-COVID-19 condition were randomly assigned to one of four 8-wk parallel intervention groups: 1) multicomponent exercise program based on concurrent training (CT, number of subjects (n) = 20; 3 resistance and endurance supervised sessions per week at low-moderate intensity); 2) inspiratory muscle training (RM, n = 17; 2 standardized daily sessions); 3) a combination of both of the above (CTRM, n = 23); and 4) control group (CON, n = 20; following the WHO guidelines for post-COVID-19-related illness rehabilitation). No significant differences between groups were detected at baseline. Although no significant differences between interventions were detected in the V̇o2max, significant individual improvements were identified in the CT (7.5%; effect size, ES = 0.28) and CTRM (7.8%; ES = 0.36) groups. Lower body muscle strength significantly improved in the CT and CTRM (14.5%-32.6%; ES = 0.27-1.13) groups compared with RM and CON (-0.3% to 11.3%; ES = 0.10-0.19). The CT and CTRM groups improved significantly for dyspnea and fatigue, as did the health status. In addition, significant differences between interventions were described in fatigue and depression scales favoring CT and CTRM interventions. An individualized and supervised concurrent training with or without inspiratory muscle training was safe and more effective than self-care recommendations and inspiratory muscle training alone, to regain cardiovascular and muscular fitness, improve symptom severity, and health status in outpatients with post-COVID-19 conditions.NEW & NOTEWORTHY Eight weeks of concurrent training, with or without inspiratory muscle exercise, was better than WHO "Support for Rehabilitation: Self-Management after COVID-19-Related Illness" recommendations or inspiratory muscle training alone to improve cardiopulmonary fitness, strength, and symptom severity, in a safe and effective manner. The RECOVE trial proved the benefits and utility of a supervised exercise program in people with post-COVID-19 conditions after mild COVID-19 in an ambulatory setting.


Assuntos
COVID-19 , Autogestão , Adulto , Humanos , Qualidade de Vida , Exercício Físico/fisiologia , Músculos Respiratórios/fisiologia , Força Muscular/fisiologia , Exercícios Respiratórios , Fadiga
9.
Scand J Med Sci Sports ; 32(12): 1791-1801, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36111386

RESUMO

PURPOSE: The aim of the study was to compare the outcomes of patients with post-COVID-19 condition undergoing supervised therapeutic exercise intervention or following the self-management WHO (World Health Organization) rehabilitation leaflet. METHODS: A randomized controlled trial was carried out that included 39 participants with post-COVID-19 condition who had a chronic symptomatic phase lasting >12 weeks. Comprehensive medical screening, patient-reported symptoms, and cardiorespiratory fitness and muscular strength were assessed. Patients were randomly assigned to a tailored multicomponent exercise program based on concurrent training for 8 weeks (two supervised sessions per week comprised resistance training combined with aerobic training [moderate intensity variable training], plus a third day of monitored light intensity continuous training), or to a control group which followed the WHO guidelines for rehabilitation after COVID-19. RESULTS: After follow-up, there were changes in physical outcomes in both groups, however, the magnitude of the change pre-post intervention favored the exercise group in cardiovascular and strength markers: VO2 max +5.7%, sit-to-stand -22.7% and load-velocity profiles in bench press +6.3%, and half squat +16.9%, (p < 0.05). In addition, exercise intervention resulted in a significantly better quality of life, less fatigue, less depression, and improved functional status, as well as in superior cardiovascular fitness and muscle strength compared to controls (p < 0.05). No adverse events were observed during the training sessions. CONCLUSION: Compared to current WHO recommendations, a supervised, tailored concurrent training at low and moderate intensity for both resistance and endurance training is a more effective, safe, and well-tolerated intervention in post-COVID-19 conditions.


Assuntos
COVID-19 , Treinamento Resistido , Humanos , Qualidade de Vida , Força Muscular/fisiologia , Terapia por Exercício/métodos
11.
Int J Sports Physiol Perform ; 17(10): 1480-1488, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35894906

RESUMO

PURPOSE: To analyze the feasibility of the 2-point method for estimating ultrasound-derived quadriceps femoris cross-sectional area (QUADACSA). First, (1) the agreement between QUADACSA measured by panoramic ultrasound and magnetic resonance imaging (MRI) was studied, and thereafter, we examined 2 approaches of the 2-point method in terms of (2) estimation errors and (3) test-retest repeatability. METHODS: Both thighs of 16 young men were analyzed. Ultrasound-QUADACSA versus MRI-QUADACSA comparison was conducted at 6 thigh lengths (20%-70% of the thigh length). Thereafter, ultrasound-QUADACSA corresponding to 30% and 60% (2-point30%-60%) or 20% and 70% (2-point20%-70%) were used to estimate QUADACSA of the remaining regions. Estimated QUADACSA resulting from both 2-point approaches was compared with the measured one. Finally, the test-retest repeatability was examined by comparing the errors generated on 2 separate estimations. Statistics included the standard error of measurement (SEM) expressed in absolute (in square centimeters) and relative terms (in percentage) as a coefficient of variation (CV), as well as the intraclass correlation cofficient (ICC) and bias. RESULTS: An excellent agreement (ICC ≥ 0.980) and reduced errors (SEM ≤ 2.43 cm2) resulted from the ultrasound-QUADACSA versus MRI-QUADACSA comparison. Although estimation errors found were reduced (CV ≤ 7.50%), they proved to be lower and less biased for the 2-point30%-60%, especially at the central regions (SEM ≤ 2.01 cm2; bias ≤ 0.89 cm2). Similarly, repeatability analysis revealed lower test-retest errors for the 2-point30%-60% (CV ≤ 1.9%) than for the 2-point20%-70% (CV ≤ 4.6%). CONCLUSION: The 2-point method, especially that implemented using the 30% and 60% regions, represents an accurate and repeatable strategy to evaluate QUADACSA.


Assuntos
Músculo Quadríceps , Coxa da Perna , Humanos , Imageamento por Ressonância Magnética , Masculino , Músculo Quadríceps/diagnóstico por imagem , Reprodutibilidade dos Testes , Coxa da Perna/diagnóstico por imagem , Ultrassonografia
12.
Intern Emerg Med ; 17(8): 2199-2208, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35904700

RESUMO

The aim of this study was to determine the relationship between physical fitness, cardiopulmonary function and patient-reported severity of symptoms in people with post-COVID-19 condition. We examined ambulatory patients (n = 72) with post-COVID-19 condition who had a chronic symptomatic phase lasting > 12 weeks from the onset of symptoms, but had not been hospitalized for acute COVID-19. A comprehensive medical screening was conducted, including clinical history, symptomatology, comorbidities, body composition and physical activity levels. We then identified the relationship between physical fitness (cardiorespiratory fitness and muscular strength), cardiopulmonary function (echocardiographic and spirometry parameters) and patient-reported severity of symptoms (fatigue, dyspnea, health-related quality of life, anxiety, and depression). Age, body mass index, sex, number of comorbidities and duration of symptoms were included as potential confounders. Results showed that greater physical fitness and cardiopulmonary function were associated with lower severity of symptoms in people with post-COVID-19 condition. Cardiorespiratory fitness, lower-limb muscle strength, maximal voluntary ventilation and left ventricular ejection fraction account for reducing fatigue and dyspnea. Greater physical activity levels were associated with fewer symptoms and less-severe fatigue and dyspnea. In conclusion, preserving better cardiopulmonary health and physical condition during the course of the disease-even in mild cases-was related to a lower intensity of symptoms in non-hospitalized people with post-COVID-19 condition. It is probable that exercise and physical conditioning are valuable pre- and post-COVID-19 countermeasures that could help decrease the severity, not only of acute infection, but of post-COVID-19 persistent symptoms and prognosis.


Assuntos
COVID-19 , Qualidade de Vida , Humanos , COVID-19/epidemiologia , Volume Sistólico , Função Ventricular Esquerda , Aptidão Física , Fadiga/etiologia , Dispneia/etiologia
13.
Int J Sports Physiol Perform ; 17(7): 1044-1053, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35361734

RESUMO

PURPOSE: To compare the strength and athletic adaptations induced by 4 programming models. METHODS: Fifty-two men were allocated into 1 of the following models: linear programming (intensity increased while intraset volume decreased), undulating programming (intensity and intraset volume were varied in each session or set of sessions), reverse programming (intensity decreased while intraset volume increased), or constant programming (intensity and intraset volume kept constant throughout the training plan). All groups completed a 10-week resistance-training program made up of the free-weight bench press, squat, deadlift, prone bench pull, and shoulder press exercises. The 4 models used the same frequency (2 sessions per week), number of sets (3 per exercise), interset recoveries (4 min), and average intensity throughout the intervention (77.5%). The velocity-based method was used to accurately adjust the planned intensity for each model. RESULTS: The 4 programming models exhibited significant pre-post changes in most strength variables analyzed. When considering the effect sizes for the 5 exercises trained, we observed that the undulating programming (mean effect size = 0.88-2.92) and constant programming (mean effect size = 0.61-1.65) models induced the highest and lowest strength enhancements, respectively. Moreover, the 4 programming models were found to be effective to improve performance during shorter (jump and sprint tests) and longer (upper- and lower-limb Wingate test) anaerobic tasks, with no significant differences between them. CONCLUSION: The linear, undulating, reverse, and constant programming models are similarly effective to improve strength and athletic performance when they are implemented in a real-context routine.


Assuntos
Desempenho Atlético , Treinamento Resistido , Aclimatação , Adaptação Fisiológica , Humanos , Masculino , Força Muscular , Treinamento Resistido/métodos
15.
Physiol Behav ; 248: 113737, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35150708

RESUMO

This study aimed to examine the validity and repeatability of panoramic ultrasound to evaluate the anatomical cross-sectional area (ACSA) of quadriceps femoris muscles. Specifically, we aimed to quantify the errors generated during the image acquisition and analysis (repeatability), as well as when comparing with magnetic resonance imaging (MRI) (validity). Moreover, we analyzed the influence of the operator's experience and the region of the thigh, on these errors. Both thighs of 16 subjects were included. The validity and repeatability study quantified the errors made by two operators (trained and novice) when measuring ACSA of vastus lateralis (VL), vastus medialis-intermedius (VMVI), and rectus femoris (RF), in six thigh regions (from 20 to 70%). Two ACSA images were acquired 5 min apart to examine acquisition errors, whereas acquisition #1 was analyzed twice to quantify analysis errors. Thereafter, ACSA of acquisition #1 was compared with that measured by MRI. Statistics included the standard error of measurement (SEM) expressed in absolute (cm2) and relative terms (%) as a coefficient of variation (CV). Measurement errors were lower for the trained operator than for the novice: Acquisition (SEM = 0.05 - 0.78 vs. 0.25 - 1.42 cm2), analysis (SEM = 0.13 - 1.93 vs. 0.30 - 3.05 cm2) and compared-with-MRI (SEM = 0.13 - 1.93 vs. 0.30 - 3.05 cm2). Regions with the lowest errors were those located at the middle of the thigh (40-50%), although slight between-muscle differences were found: VMVI (30-40%), VL (40-50%), RF (50-60%). These findings suggest that the accurate implementation of panoramic ultrasound to measure ACSA of quadriceps femoris muscles requires a trained operator and specific evaluation sites.


Assuntos
Imageamento por Ressonância Magnética , Músculo Quadríceps , Humanos , Extremidade Inferior , Músculo Quadríceps/diagnóstico por imagem , Ultrassonografia
16.
Ultrasound Med Biol ; 48(3): 460-468, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34857426

RESUMO

The objective of the current study was to examine the validity and repeatability of panoramic ultrasound in evaluating the anatomical cross-sectional area (ACSA) of the pectoralis major. Specifically, we aimed to quantify the measurement errors generated during the image acquisition and analysis (repeatability), as well as when comparing with magnetic resonance imaging (MRI) (validity). Moreover, we aimed to analyze the influence of the operator's experience on these measurement errors. Both sides of the chest of 16 participants (n = 32) were included. Errors made by two operators (trained and novice) when measuring pectoralis major ACSA (50% of sternum-areola mammae distance) were examined. Acquisition errors included the comparison of two images acquired 5 min apart. Acquisition 1 was analyzed twice to quantify analysis errors. Thereafter, acquisition 1 was compared with MRI. Statistics include the standard error of measurement (SEM), expressed in absolute (cm2) and relative (%) terms as a coefficient of variation (CV), and the calculation of systematic bias. Errors made by the trained operator were lower than those made by the novice, especially during the image acquisition (SEM = 0.25 vs. 0.66 cm2, CV = 1.06 vs. 2.98%) and when compared with MRI (SEM = 0.27 vs. 1.90 cm2, CV = 1.13 vs. 8.16%). Furthermore, although both operators underestimated the ACSA, magnitude and variability [SD] of these errors were lower for the trained operator (bias = -0.19 [0.34] cm2) than for the novice (bias = -1.97 [2.59] cm2). Panoramic ultrasound is a valid and repeatable technique for measuring pectoralis major ACSA, especially when implemented by a trained operator.


Assuntos
Imageamento por Ressonância Magnética , Músculos Peitorais , Animais , Humanos , Músculos Peitorais/diagnóstico por imagem , Reprodutibilidade dos Testes , Ultrassonografia
17.
J Strength Cond Res ; 36(1): 10-15, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31567719

RESUMO

ABSTRACT: Martínez-Cava, A, Hernández-Belmonte, A, Courel-Ibáñez, J, Morán-Navarro, R, González-Badillo, JJ, and Pallarés, JG. Bench press at full range of motion produces greater neuromuscular adaptations than partial executions after prolonged resistance training. J Strength Cond Res 36(1): 10-15, 2022-Training at a particular range of motion (ROM) produces specific neuromuscular adaptations. However, the effects of full and partial ROM in one of the most common upper-limb exercises such as the bench press (BP) remain controversial. In this study, 50 recreationally to highly resistance trained men were randomly assigned to 1 of 4 training groups: full bench press (BPFULL), two-thirds bench press (BP2/3), and one-third bench press (BP1/3) and control (training cessation). Experimental groups completed a 10-week velocity-based resistance training program using the same relative load (linear periodization, 60-80% 1 repetition maximum [1RM]), only differing in the ROM trained. Individual ROM for each BP variation was determined in the familiarization and subsequently replicated in every lift during training and testing sessions. Neuromuscular adaptations were evaluated by 1RM strength and mean propulsive velocity (MPV). The BPFULL group obtained the best results for the 3 BP variations (effect size [ES] = 0.52-1.96); in turn, partial BP produced smaller improvements as the ROM decreased (BP2/3: ES = 0.29-0.78; BP1/3: ES = -0.01 to 0.66). After 10-week of training cessation, the control group declined in all neuromuscular parameters (ES = 0.86-0.92) except in MPV against low loads. Based on these findings, the BPFULL stands as the most effective exercise to maximize neuromuscular improvements in recreational and well-trained athletes compared with partial ROM variations.


Assuntos
Treinamento Resistido , Adaptação Fisiológica , Humanos , Masculino , Força Muscular , Músculo Esquelético , Amplitude de Movimento Articular , Levantamento de Peso
18.
J Strength Cond Res ; 36(1): 167-173, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31714462

RESUMO

ABSTRACT: Lillo-Beviá, JR, Courel-Ibáñez, J, Cerezuela-Espejo, V, Morán-Navarro, R, Martínez-Cava, A, and Pallarés, JG. Is the functional threshold power a valid metric to estimate the maximal lactate steady state in cyclists? J Strength Cond Res 36(1): 167-173, 2022-The aims of this study were to determine (a) the repeatability of a 20-minute time-trial (TT20), (b) the location of the TT20 in relation to the main physiological events of the aerobic-anaerobic transition, and (c) the predictive power of a list of correction factors and linear/multiple regression analysis applied to the TT20 result to estimate the individual maximal lactate steady state (MLSS). Under laboratory conditions, 11 trained male cyclists and triathletes (V̇o2max 59.7 ± 3.0 ml·kg-1·min-1) completed a maximal graded exercise test to record the power output associated with the first and second ventilatory thresholds and V̇o2max measured by indirect calorimetry, several 30 minutes constant tests to determine the MLSS, and 2 TT20 tests with a short warm-up. Very high repeatability of TT20 tests was confirmed (standard error of measurement of ±3 W and smallest detectable change of ±9 W). Validity results revealed that MLSS differed substantially from TT20 (bias = 26 ± 7 W). The maximal lactate steady state was then estimated from the traditional 95% factor (bias = 12 ± 7 W) and a novel individual correction factor (ICF% = MLSS/TT20), resulting in 91% (bias = 1 ± 6 W). Complementary linear (MLSS = 0.7488 × TT20 + 43.24; bias = 0 ± 5 W) and multiple regression analysis (bias = 0 ± 4 W) substantially improved the individual MLSS workload estimation. These findings suggest reconsidering the TT20 procedures and calculations to increase the effectiveness of the MLSS prediction.


Assuntos
Limiar Anaeróbio , Ácido Láctico , Ciclismo , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio
19.
Int J Sports Physiol Perform ; 17(1): 120-125, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34186508

RESUMO

PURPOSE: To examine the reproducibility (intradevice and interdevice agreement) of the Rotor 2INpower device under a wide range of cycling conditions. METHODS: Twelve highly trained male cyclists and triathletes completed 5 cycling tests, including graded exercise tests at different cadences (70-100 rpm), workloads (100-650 W), pedaling positions (seated and standing), and vibration conditions (20-40 Hz) and an 8-second maximal sprint (>1000 W). An intradevice analysis included a comparison between the power output registered by 3 units of Rotor 2INpower, whereas the power output provided by each one of these units and the gold-standard SRM crankset were compared for the interdevice analysis. Among others, statistical calculations included the standard error of measurement, expressed in absolute (in watts) and relative terms as the coefficient of variation (CV). RESULTS: Except for the graded exercise test seated at 100 rpm/100 W (CV = 10.2%), the intradevice analysis showed an acceptable magnitude of error (CV ≤ 6.9%, standard error of measurement ≤ 12.3 W) between the 3 Rotor 2INpower. Similarly, these 3 units showed an acceptable agreement with the gold standard in all graded exercise test situations (CV ≤ 4.0%, standard error of measurement ≤ 13.1 W). On the other hand, both the intradevice and interdevice agreements proved to be slightly reduced under high cadences (intradevice: CV ≤ 10.2%; interdevice: CV ≤ 4.0%) and vibration (intradevice: CV ≤ 4.0%; interdevice: CV ≤ 3.6%), as well as during standing pedaling (intradevice: CV ≤ 4.1%; interdevice: CV ≤ 2.5%). Although within the limits of an acceptable agreement, measurement errors increased during the sprint tests (CV ≤ 7.4%). CONCLUSIONS: Based on these results, the Rotor 2INpower could be considered a reproducible tool to monitor power output in most cycling situations.


Assuntos
Ciclismo , Teste de Esforço , Humanos , Masculino , Reprodutibilidade dos Testes , Postura Sentada , Posição Ortostática
20.
J Strength Cond Res ; 36(11): 2992-2999, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34027915

RESUMO

ABSTRACT: Hernández-Belmonte, A, Courel-Ibáñez, J, Conesa-Ros, E, Martínez-Cava, A, and Pallarés, JG. Level of effort: A reliable and practical alternative to the velocity-based approach for monitoring resistance training. J Strength Cond Res 36(11): 2992-2999, 2022-This study analyzed the potential of the level of effort methodology as an accurate indicator of the programmed relative load (percentage of one-repetition maximum [%1RM]) and intraset volume of the set during resistance training in the bench press, full squat, shoulder press, and prone bench pull exercises, through 3 specific objectives: (a) to examine the intersubject and intrasubject variability in the number of repetitions to failure ( n RM) against the actual %1RM lifted (adjusted by the individual velocity), (b) to investigate the relationship between the number of repetitions completed and velocity loss reached, and (c) to study the influence of the subject's strength level on the aforementioned parameters. After determining their individual load-velocity relationships, 30 subjects with low ( n = 10), medium ( n = 10), and high ( n = 10) relative strength levels completed 2 rounds of n RM tests against their 65, 75, 85, and 95% 1RM in the 4 exercises. The velocity of all repetitions was monitored using a linear transducer. Intersubject and intrasubject variability analyses included the 95% confidence intervals (CIs) and the the standard error of measurement ( SEM ), respectively. Coefficient of determination (R 2 ) was used as the indicator of relationship. n RM showed a limited intersubject (CI ≤ 4 repetitions) and a very low intrasubject ( SEM ≤1.9 repetitions) variability for all the strength levels, %1RM, and exercises analyzed. A very close relationship ( R2 ≥ 0.97) between the number of repetitions completed and the percentage of velocity loss reached (from 10 to 60%) was found. These findings strengthen the level of effort as a reliable, precise, and practical strategy for programming resistance training.


Assuntos
Treinamento Resistido , Humanos , Treinamento Resistido/métodos , Levantamento de Peso , Força Muscular , Espécies Reativas de Oxigênio , Músculo Esquelético
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