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1.
J Strength Cond Res ; 37(1): 230-233, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36515611

RESUMO

ABSTRACT: Rodríguez-Marroyo, JA, Blanco, P, Foster, C, Villa, JG, and Carballo-Leyenda, B. Expanding knowledge about the effect of measurement time on session rating of perceived exertion. J Strength Cond Res 37(1): 230-233, 2023-The purpose of this study was to analyze the effect of postexercise rating times (from 0 minutes to 4 weeks) on session rating of perceived exertion (sRPE). Twenty-five athletes (12 women and 13 men) from different sports (sprinting, endurance running, cycling, and volleyball) were involved in this study. At least 3 training sessions per subject were quantified based on sRPE using a visual analog scale. The scale was administered immediately after, at 5, 10, 20, and 30 minutes, 24, 48, and 72 hours, and 1, 2, 3, and 4 weeks postexercise. In addition, the effect of rating time on sRPE was studied according to the training intensity. For this, the training sessions were classified (based on the 30-minute rating) as easy (sRPE < 3), moderate (sRPE 3-5), and hard (sRPE > 5). A significant (p < 0.001) main effect of the postexercise rating time on sRPE was found. There were significant (p < 0.05) differences between sRPE obtained at 30 minutes and those obtained immediately after hard training sessions and at 1, 2, 3, and 4 weeks postexercise. There was no significant effect of rating time on sRPE in the easy and moderate training sessions. In conclusion, the present data suggest that athletes' sRPE may be obtained in a valid and reliable manner within a time frame of 5 minutes to 72 hours posttraining. The effect of postexercise rating time on sRPE seems to be conditioned by the training intensity, especially in those training sessions whose training intensity was high (sRPE > 5).


Assuntos
Condicionamento Físico Humano , Corrida , Masculino , Humanos , Feminino , Esforço Físico , Atletas , Ciclismo , Conhecimento
2.
J Strength Cond Res ; 34(8): 2128-2135, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32735423

RESUMO

Rodríguez-Fernández, A, Villa, JG, Sánchez-Sánchez, J, and Rodríguez-Marroyo, JA. Effectiveness of a generic vs. specific program training to prevent the short-term detraining on repeated-sprint ability of youth soccer players. J Strength Cond Res 34(8): 2128-2135, 2020-The aim of this study was to analyze the effects of 2 short-term training programs to prevent the negative effect of detraining on repeated-sprint ability (RSA) performance. The study was performed during a 2-week midseason break without official matches. Forty-five youth soccer players (17.7 ± 0.8 years, 175.4 ± 5.5 cm, and 67.2 ± 5.1 kg) were split into 3 groups during the intervention period: inactivity group (IN; N = 16), generic high-intensity training group (GG; N = 15), and specific training group (SG; N = 14). IN was instructed to avoid performing physical activity during the 2-week training intervention. However, GG and SG performed 8 training sessions. GG performed a generic aerobic interval training consisting of 4 repetitions of 4 minutes of exercise at 90-95% of maximal heart rate. SG performed a specific conditioning through small-sided games (4 vs. 4, 4 × 4-minute) and repeated sprints (6 × 30-m). Testing sessions included an RSA test and a Yo-Yo intermittent recovery test level 1 (YYIR1). Repeated-sprint ability performance only improved after the training intervention in SG (∼2%, p < 0.01, (Equation is included in full-text article.)= 0.23-0.25). Both GG and IN declined their performance in post-test (∼2%, p < 0.01, (Equation is included in full-text article.)= 0.19-0.22). No significant effect, group × time, was analyzed for YYIR1 performance. This study suggests that only specific training, based on small-sided games and repeated sprints, leads to short-term improvements on RSA performance in youth soccer players.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adolescente , Exercício Físico/fisiologia , Humanos , Masculino , Condicionamento Físico Humano/fisiologia
3.
J Strength Cond Res ; 33(12): 3406-3413, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31765346

RESUMO

Rodríguez-Fernández, A, Sanchez-Sanchez, J, Ramirez-Campillo, R, Nakamura, FY, Rodríguez-Marroyo, JA, and Villa-Vicente, JG. Relationship between repeated sprint ability, aerobic capacity, intermittent endurance, and heart rate recovery in youth soccer players. J Strength Cond Res 33(12): 3406-3413, 2019-To investigate the relationship between repeated sprint ability (RSA) and several aerobic and anaerobic-related soccer-performance indicators, 45 youth soccer players (age 16.8 ± 0.1 years) were classified into "high" (HAF) or "low" aerobic fitness (LAF) (VO2max ≥ or <60 ml·kg·min, respectively) and completed an RSA test measuring best (RSAbest), mean (RSAmean), total sprint time (RSAtotal), and percent sprint decrement (Sdec). A laboratory VO2max test (LabTest) together with anaerobic threshold (VT) and peak speed was measured (vLabTest). In addition, a 20-m multistage shuttle run test (MSRT) and a soccer-specific test (TIVRE-Soccer test-TST) were completed. Heart rate (HR) and HR recovery (HRR) were measured during all tests. High aerobic fitness presented greater (p ≤ 0.05) performance in LabTest, MSRT and TST, at maximal effort, at VT, as well as faster HRR. RSA was similar between HAF and LAF. Contrary to HAF, LAF showed negative correlation between vLabTest with RSAmean (r = -0.6, p = 0.000) and Sdec (r = -0.4, p = 0.044). Also, LAF showed negative correlation between TST end speed (vTST) and RSAmean (r = -0.5, p = 0.005) and Sdec (r = -0.5, p = 0.003). In LAF, RSA was strongly correlated with locomotor factors (e.g., vTST; VT) in both laboratory and field tests. Athletes with high total HRR (>12.5%) in TST presented better (p ≤ 0.05) Sdec in the RSA test. The multiple regression revealed that the LAF vLabTest explained 44.9, 40.0, and 13.5% of the variance in RSAbest, RSAmean, and Sdec, respectively. Practitioners may consider these findings to optimize youth athletes' assessment and preparation processes.


Assuntos
Limiar Anaeróbio , Aptidão Cardiorrespiratória/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adolescente , Desempenho Atlético/fisiologia , Estudos Transversais , Teste de Esforço , Tolerância ao Exercício , Frequência Cardíaca , Humanos , Adulto Jovem
4.
J Sports Sci ; 35(14): 1328-1335, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27484153

RESUMO

The main purpose of this study was to assess the acute effects of small changes in crank length (assumable by competitive cyclists) on metabolic cost and pedalling technique during submaximal cycling. Twelve amateur road cyclists performed three sets of submaximal pedalling (150, 200 and 250 W) at a constant cadence (91.3 ± 0.8 rpm) in a randomised order with three commonly used crank lengths, preferred (172.5-175 mm), +5 mm and -5 mm. Energy cost of pedalling, kinetic and kinematic variables were simultaneously registered. Changes in crank length had no significant effect on heart rate (144 ± 13, 145 ± 12 and 145 ± 13 bpm, respectively) and gross efficiency (GE) (20.4 ± 2.1, 20.1 ± 2.2 and 20.3 ± 2.4%, respectively). A longer crank induced a significant (P < 0.05) reduction of positive impulse proportion (PIP) (0.9-1.9%) due to a greater maximum (1.0-2.3 N · m) and minimum torque (1.0-2.2 N · m). At the same time, the maximum flexion and range of motion of the hip and knee joints were significantly increased (1.8-3.4° and P < 0.05), whereas the ankle joint was not affected. In conclusion, the biomechanical changes due to a longer crank did not alter the metabolic cost of pedalling, although they could have long-term adverse effects. Therefore, in case of doubt between two lengths, the shorter one might be recommended.


Assuntos
Ciclismo/fisiologia , Metabolismo Energético/fisiologia , Equipamentos Esportivos , Adolescente , Adulto , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos , Desenho de Equipamento , Frequência Cardíaca/fisiologia , Articulação do Quadril/fisiologia , Humanos , Articulação do Joelho/fisiologia , Adulto Jovem
5.
J Sports Sci Med ; 16(2): 187-194, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28630571

RESUMO

The aims of this study were to establish and validate various predictive equations of half-marathon performance. Seventy-eight half-marathon male runners participated in two different phases. Phase 1 (n = 48) was used to establish the equations for estimating half-marathon performance, and Phase 2 (n = 30) to validate these equations. Apart from half-marathon performance, training-related and anthropometric variables were recorded, and an incremental test on a treadmill was performed, in which physiological (VO2max, speed at the anaerobic threshold, peak speed) and biomechanical variables (contact and flight times, step length and step rate) were registered. In Phase 1, half-marathon performance could be predicted to 90.3% by variables related to training and anthropometry (Equation 1), 94.9% by physiological variables (Equation 2), 93.7% by biomechanical parameters (Equation 3) and 96.2% by a general equation (Equation 4). Using these equations, in Phase 2 the predicted time was significantly correlated with performance (r = 0.78, 0.92, 0.90 and 0.95, respectively). The proposed equations and their validation showed a high prediction of half-marathon performance in long distance male runners, considered from different approaches. Furthermore, they improved the prediction performance of previous studies, which makes them a highly practical application in the field of training and performance.

6.
J Sports Sci ; 34(17): 1619-26, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26703374

RESUMO

The purpose of this study was to compare the pedalling technique in road cyclists of different competitive levels. Eleven professional, thirteen elite and fourteen club cyclists were assessed at the beginning of their competition season. Cyclists' anthropometric characteristics and bike measurements were recorded. Three sets of pedalling (200, 250 and 300 W) on a cycle ergometer that simulated their habitual cycling posture were performed at a constant cadence (~90 rpm), while kinetic and kinematic variables were registered. The results showed no differences on the main anthropometric variables and bike measurements. Professional cyclists obtained higher positive impulse proportion (1.5-3.3% and P < 0.05), mainly due to a lower resistive torque during the upstroke (15.4-28.7% and P < 0.05). They also showed a higher ankle range of movement (ROM, 1.1-4.0° and P < 0.05). Significant correlations (P < 0.05) were found between the cyclists' body mass and the kinetic variables of pedalling: positive impulse proportion (r = -0.59 to -0.61), minimum (r = -0.59 to -0.63) and maximum torques (r = 0.35-0.47). In conclusion, professional cyclists had better pedalling technique than elite and club cyclists, because they opted for enhancing pulling force at the recovery phase to sustain the same power output. This technique depended on cycling experience and level of expertise.


Assuntos
Ciclismo/fisiologia , Comportamento Competitivo/fisiologia , Extremidade Inferior/fisiologia , Adulto , Tornozelo/fisiologia , Antropometria , Fenômenos Biomecânicos , Desenho de Equipamento , Ergometria , Quadril/fisiologia , Humanos , Joelho/fisiologia , Postura , Amplitude de Movimento Articular , Equipamentos Esportivos , Torque , Adulto Jovem
7.
J Strength Cond Res ; 28(6): 1588-94, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24276301

RESUMO

The main aim of this study was to compare the training load (TL) executed by volleyball players with that observed by coaches. Second, we analyzed the influence of the coaches' experience in the estimated TL. Twelve female volleyball players and 4 male coaches participated in this study. During a period of 15 weeks, physical (PT) and technical-tactical training sessions and matches were monitored. In each session, the session rating of perceived exertion (sRPE) was recorded to analyze the players' exercise intensity and TL(RP)E. Coaches were present in all sessions and rated their estimate of sRPE at the same time as the players to calculate the coaches' TL(RPE). Both players' and coaches' mean sRPE (4.0 ± 1.1, 3.7 ± 1.1, and 3.8 ± 1.0 in players and expert and beginning coaches, respectively) and TLRPE (380.1 ± 106.8, 358.3 ± 110.5, and 359.7 ± 108.0 in players and expert and beginning coaches, respectively) were similar. However, a higher (p < 0.01) sRPE and TL(RPE) were observed in the players during PT. In general, the weekly TL(RPE) variation over the course of this study was similar in players and coaches. The players' sRPE and TL(RPE) were correlated (p < 0.01) with expert and beginner coaches' RPE (r = 0.70 and 0.72, respectively) and TL(RPE) (r = 0.75 and 0.76, respectively). In conclusion, the present findings show the correspondence between players' and coaches' sRPE and TL(RPE) regardless of their experience. Hence, coaches' TL(RPE) could be a useful and practical method to monitor and control the TL and other derived parameters in an easy way during volleyball.


Assuntos
Desempenho Atlético/fisiologia , Educação Física e Treinamento/métodos , Voleibol/fisiologia , Feminino , Humanos , Percepção , Esforço Físico/fisiologia , Adulto Jovem
8.
Sports (Basel) ; 12(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393271

RESUMO

This study aimed to compare the effects of an 8-week short-term training program, comprising repeated sprints or running-based high-intensity intermittent training (HIIT), on the aerobic fitness and repeated sprint ability (RSA) performance of sub-elite basketball referees. Twenty male referees participated in supervised training sessions twice a week. They were randomly assigned to either the RSA-based group (RSAG) or the running-based HIIT group (HIITG). The RSAG conducted 3-4 sets of 8 × 20-m all-out sprints, while the HIITG performed 2-3 sets of 6 × 20-s runs at 90% of their maximal velocity achieved in the 30-15 intermittent fitness test (30-15IFT). Referees underwent a graded exercise test on a treadmill, the 30-15IFT, and an RSA test before and after the training program. Both groups showed significant improvement (~3%) in the fastest (22.6 ± 1.4 vs. 23.4 ± 1.7 and 22.0 ±1.9 vs. 22.4 ± 1.7 km·h-1 in RSAG and HIITG, respectively) and mean (21.5 ± 1.2 vs. 22.4 ± 1.4 and 21.3 ± 1.8 vs. 21.7 ± 1.6 km·h-1 in RSAG and HIITG, respectively) sprint velocity of the RSA test (p < 0.05). Moreover, positive changes (p < 0.05) were observed in the 30-15IFT maximal velocity (18.6 ± 1.1 vs. 19.3 ± 1.0 and 19.4 ± 0.9 vs. 20.5 ± 0.9 km·h-1 in RSAG and HIITG, respectively). In conclusion, an 8-week training intervention using either RSA or running-based HIIT led to similar improvements in referees' RSA performance and specific aerobic fitness measures. These findings could assist in devising tailored training programs for basketball referees.

9.
Front Psychol ; 15: 1363544, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962225

RESUMO

Purpose: Recreational and competitive slalom waterskiing is increasingly popular among individuals with spinal cord injuries (SCI), particularly for those with paraplegia using sit-skis. A key component of slalom skiing is the deep-water start (DWS), yet little is known about the physiological and physical demands of this activity when the athlete is seated. This study aims to fill this gap by focusing on the training requirements for a seated slalom athlete. Materials and methods: Focusing on a young male athlete with paraplegia, this case study evaluates the effectiveness and efficiency of traditional (TDWS) and alternative (ADWS) DWS techniques during seated slalom waterskiing sessions. It assesses internal training load (TL) through heart rate (HR) zones and session rating of perceived exertion (sRPE), alongside pre- and post-session handgrip strength measurements to gauge peripheral muscle fatigue. Results and conclusions: Performing the ADWS, achieving a full success rate, proved more effective but slightly more time-consuming than TDWS, which had limited success. HR during DWS maneuvers ranged from 63.2 to 81.3% of maximal HR, with most sessions occurring below the ventilatory threshold, thus perceived as hard effort. A moderate yet non-significant correlation was found between HR and sRPE-based TL. A significant reduction in handgrip strength post-session underscores the activity's demands. These insights illuminate the technical, physiological, and physical challenges in mastering DWS for seated slalom athletes with SCI, providing valuable guidance for the development of tailored training programs and techniques in this sport.

10.
Front Public Health ; 12: 1408591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39171317

RESUMO

Background: Wildland firefighters (WFFs) regularly face demanding physical and environmental conditions during their duties, such as high ambient temperatures, challenging terrains, heavy equipment and protective gear. These conditions can strain thermoregulatory responses, leading to increased fatigue and posing risks to their health and safety. This study examined the effectiveness of two cooling interventions during physical activity in hot environments. Methods: Eight active male WFFs participated, comparing the effects of wearing a cooling vest (VEST) and personal protective equipment removal (PASSIVE) against a control condition (PPE). Participants walked on a treadmill at a speed of 6 km·h-1 for approximately 75-min under hot conditions (30°C and 30% relative humidity). Incremental slope increases were introduced every 15 min after the initial 20 min of activity, with 5-min passive recovery between each increment. Physiological and perceptual parameters were monitored throughout the protocol. Results: Significant main effects (p < 0.05) were observed in skin temperature (36.3 ± 0.2, 36.2 ± 0.4 and 35.4 ± 0.6°C in PPE, PASSIVE and VEST, respectively), physiological strain index (5.2 ± 0.4, 5.6 ± 1.1 and 4.3 ± 1.4 in PPE, PASSIVE and VEST) and thermal sensation (6.6 ± 0.6, 6.4 ± 0.7 and 5.3 ± 0.7 in PPE, PASSIVE, and VEST). However, no significant effects of the cooling strategies were observed on heart rate, gastrointestinal temperature or performance. Conclusion: Despite the observed effects on physiological responses, neither cooling strategy effectively mitigated thermal strain in WFFs under the experimental conditions tested.


Assuntos
Regulação da Temperatura Corporal , Bombeiros , Equipamento de Proteção Individual , Roupa de Proteção , Humanos , Masculino , Regulação da Temperatura Corporal/fisiologia , Adulto , Temperatura Cutânea/fisiologia , Temperatura Alta , Frequência Cardíaca/fisiologia
11.
Ann Nutr Metab ; 63(3): 223-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24192533

RESUMO

BACKGROUND/AIMS: The prevalence of overweight and obesity in childhood is increasing markedly. The aim of this study was to evaluate the relationship between physical activity, energy consumption and weight status in a cohort of Spanish children. METHODS: A total of 137 children (11-13 years old) participated in the study voluntarily (with paternal consent). Children were classified into 3 groups according to their physical activity, i.e. sedentary, active and sporty groups. Body composition measures, physical fitness and total caloric and macronutrient intake were determined. RESULTS: Weight, body mass index, waist circumference, skinfold thickness measures and body fat percentage of children were lower in the active children, whereas body water content increased with activity. Nutritional habits were similar in the 3 studied groups. No significant differences in total energy intake or percentage of carbohydrates, fat and proteins were found. All parameters related to caloric expenditure were higher in children carrying out more physical activity. CONCLUSIONS: Children with higher levels of physical activity presented more favorable anthropometric profiles, but there were no differences in respect to their dietary habits. An increase in weekly energy expenditure through physical activity outside school seems essential to prevent overweight and the risk of childhood obesity.


Assuntos
Composição Corporal , Ingestão de Energia , Atividade Motora , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Adolescente , Índice de Massa Corporal , Peso Corporal , Criança , Estudos Transversais , Metabolismo Energético , Comportamento Alimentar , Feminino , Humanos , Masculino , Sobrepeso , Prevalência , Dobras Cutâneas , Espanha/epidemiologia , Circunferência da Cintura , População Branca
12.
J Strength Cond Res ; 27(7): 1942-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23007491

RESUMO

The aim of this study was to extend the range of populations where the Talk Test (TT) might be used as a marker of physiologic thresholds. Eighteen highly trained cyclists underwent 2 incremental tests. One test included measurement of respiratory gas exchange to determine the ventilatory (VT) and respiratory compensation thresholds (RCTs). On a separate day, a TT was performed using the same exercise protocol. During TT, subjects read a standard paragraph at the end of each stage. The first stage at which the cyclists could not talk comfortably and could definitely not talk were referred to as the equivocal (EQ) and the negative stages (NEG), respectively. There were no significant differences in workload, heart rate, lactate, and rating of perceived exertion between VT (3.7 ± 0.4 W kg, 150 ± 10 b min, 1.6 ± 0.3 mm L, and 4.1 ± 1.4, respectively) vs. EQ (3.6 ± 0.4 W kg, 148 ± 12 b min, 1.3 ± 0.5 mm L, and 3.8 ± 1.2, respectively) and RCT (5.3 ± 0.4 W kg, 177 ± 7 b min, 4.0 ± 0.9 mm L, and 7.2 ± 1.0, respectively) vs. NEG (5.3 ± 0.5 W kg, 176 ± 10 b min, 4.2 ± 1.3 mm L, and 6.8 ± 1.5, respectively). We found significant relationships (p < 0.01) between VT and EQ and RCT and NEG for workload (r = 0.86 and 0.94, respectively), heart rate (r = 0.79 and 0.92, respectively), and rating of perceived exertion (r = 0.79 and 0.88, respectively). In conclusion, the present study showed that the EQ and NEG stages of TT can be used as a simple and practical surrogate of the VT and RCT in highly trained cyclists.


Assuntos
Limiar Anaeróbio/fisiologia , Ciclismo/fisiologia , Fala/fisiologia , Ergometria , Teste de Esforço , Humanos , Masculino , Esforço Físico/fisiologia , Troca Gasosa Pulmonar/fisiologia , Ventilação Pulmonar/fisiologia , Adulto Jovem
13.
J Strength Cond Res ; 27(4): 1162-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22744294

RESUMO

The purposes of this study were to analyze the validity and reliability of 2 photocell mats and to probe the possible influence of the type of mat (contact vs. photocell) on vertical jump height estimated from flight time. In 2 separate studies, 89 and 92 physical students performed 3 countermovement jumps that were simultaneously registered by a Force Plate (gold standard method), 2 photocell mats (SportJump System Pro and ErgoJump Plus), and a contact mat (SportJump-v1.0). The first study showed that the 2 photocell mats underestimated the vertical jump height (1.3 ± 0.2 cm and 5.9 ± 5.2 cm, respectively), but only SportJump System Pro showed a high correlation with the Force Plate (r = 0.999 and 0.676, respectively) and good intraday reliability (coefficient of variation = 2.98 and 15.94%, intraclass correlation coefficients = 0.95-0.97 and 0.45-0.57, respectively). The second study demonstrated a strong correlation (r = 0.994) between the 2 technologies (contact vs. photocell mats) with differences in vertical jump height of 2.0 ± 0.8 cm (95% confidence interval = 1.9-2.1 cm), which depended on both flight time and subjects' body mass. In conclusion, SportJump System Pro was a valid and reliable device. The new devices to measure vertical jump height from flight time should be validated. The type of mat (contact vs. photocell) affected approximately 6% the vertical jump height (approximately 2 cm in this study), which should be considered in further studies. The use of validated photocell mats instead of the contact mats was recommended.


Assuntos
Teste de Esforço/instrumentação , Movimento , Análise e Desempenho de Tarefas , Adulto , Fenômenos Biomecânicos , Intervalos de Confiança , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
14.
J Strength Cond Res ; 27(5): 1455-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22836607

RESUMO

The purpose of this study was to validate a new method to measure contact and flight times during treadmill running and to test its reliability and sensitivity. Fifteen well-trained runners performed 7 sets of running at different speeds (from 10 to 22 km·h). Contact and flight times were simultaneously recorded by a high-speed video system (gold standard method) and a new method based on laser technology (SportJump System Pro). Athletes were classified according to their foot strike pattern (rearfoot vs. midfoot and forefoot). The new method overestimated the contact time and underestimated the flight time with respect to the gold standard method (p < 0.001). However, relationships and intraclass correlation coefficients (ICCs) between both systems were very strong (r and ICC > 0.99, p < 0.001). Contact time differences between the 2 systems depended on running speed (p < 0.001) but not on foot strike pattern or runners' body mass. This allowed to correct the differences in contact time and flight time. The new method was sensitive for detecting small differences in contact time (<20 ms) when the running speed increased and when the type of foot strike patterns changed. Additionally, a low intraindividual step variability (coefficient of variation = 2.0 ± 0.5%) and high intra- (ICC = 0.998) and interobserver (ICC = 0.977) reliability were shown. In conclusion, the new method was validated, being reliable and sensitive for detecting small differences in contact and flight times during treadmill running. Therefore, it could be used to compare biomechanical variables between groups in cross-sectional studies and to verify the influence of some independent variables (i.e., training, running economy, or performance) on running biomechanics.


Assuntos
Desempenho Atlético/fisiologia , Teste de Esforço/instrumentação , Marcha/fisiologia , Lasers , Corrida/fisiologia , Adulto , Fenômenos Biomecânicos , , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravação em Vídeo
15.
Artigo em Inglês | MEDLINE | ID: mdl-36767438

RESUMO

Wildland firefighting implies high physical and psychological demands for the personnel involved. Therefore, good physical fitness can help increase the work efficiency of wildland firefighters (WFFs) and safeguard their health. High-intensity circuit training (HICT) could be a good alternative to improve the physical condition of WFFs since it stands out for its functionality and economy. Therefore, the objective of this study was to analyze the effects of HICT on the WFFs' physical fitness. The study involved 9 WFFs (8 males and 1 female; 29.8 ± 2.8 years; 175.6 ± 6.7 cm) who completed a training program and 9 WFF candidates (8 males and 1 female; 24.7 ± 6.6 yr, 176.5 ± 7.0 cm) as a control group. WFFs performed an 8-week HICT program (two weekly training sessions). The training sessions lasted approximately 45 min and were performed at an intensity >80% of maximal heart rate and RPE values >7.5. At the beginning and the end of the intervention, subjects' physical fitness (i.e., aerobic capacity, cardiorespiratory endurance, muscular resistance and explosive strength) was assessed through different tests. After completing the training program, WFFs had significantly increased (p < 0.05) the speed at which the ventilatory thresholds were determined (12.4 ± 13.9 and 5.7 ± 7.3% for the ventilatory and respiratory compensation thresholds, respectively) and also their abdominal (31.2 ± 17.2%), lumbar (34.1 ± 13.5%) and upper limb (13.3 ± 16.0%) strength. Moreover, improvements (p < 0.05) in the explosive strength of legs (7.1 ± 5.8%) and performance in a specific physical employment test (12.2 ± 6.1%) were observed. In conclusion, the results of this study show that an 8-week high-intensity circuit training program could be an effective and safe method to improve WFFs' physical fitness and performance.


Assuntos
Exercícios em Circuitos , Bombeiros , Treinamento Resistido , Masculino , Humanos , Feminino , Exercícios em Circuitos/métodos , Aptidão Física/fisiologia , Tolerância ao Exercício , Exame Físico , Força Muscular/fisiologia , Resistência Física/fisiologia , Treinamento Resistido/métodos
16.
Int Arch Occup Environ Health ; 85(2): 221-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21656120

RESUMO

PURPOSE: The aim of this study was to analyze the physiological demands and thermal strain of wildland firefighters during real wildfire suppression. METHODS: The response of core temperature and heart rate (HR) were analyzed in 200 wildland firefighters during wildfire suppression activities of different duration: <1 h (n = 52), 1-3 h (n = 70), 3-5 h (n = 44), and >5 h (n = 34). The exercise workload (TRIMP), the physiological strain index (PSI), and cumulative heat strain index (CHSI) were calculated using the time spent in different intensity zones, the HR, and core temperature. RESULTS: Mean HR was significantly higher (P < 0.05) in wildfires <1 h (133 ± 2 bpm) and 1-3 h (128 ± 1 bpm) versus 3-5 h (120 ± 3 bpm) and >5 h (116 ± 32 bpm). The time spent in higher intensity zones increased (P < 0.05) when wildfire duration increased. TRIMP accumulation increased with wildfire duration (54.9 ± 3.2, 167.4 ± 5.9, 296.0 ± 8.3, 511.7 ± 12.8 in <1, 1-3, 3-5, and >5 h, respectively). Neither core temperature (37.4 ± 0.1°C) nor PSI (4.5 ± 0.2) were influenced by wildfire duration. The CHSI increased (p < 0.05) in the following order: <1 h (104 ± 23), 1-3 h (1,396 ± 275), 3-5 h (4,586 ± 387), and >5 h (10,703 ± 710). CONCLUSIONS: The results demonstrate the high work strain sustained by Spanish wildland firefighters during wildfire suppression. Both workload and CHSI increased with the wildfires duration although the pace of work was faster in wildfires of a shorter duration.


Assuntos
Temperatura Corporal , Incêndios , Frequência Cardíaca , Exposição Ocupacional , Esforço Físico , Estresse Fisiológico/fisiologia , Adulto , Análise de Variância , Temperatura Alta , Humanos , Espanha , Estatísticas não Paramétricas , Fatores de Tempo , Carga de Trabalho
17.
J Strength Cond Res ; 26(8): 2249-57, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21997452

RESUMO

The aim of this study was to analyze the competition load using the session rating of perceived exertion (RPE) during different professional cycling races and to assess its validity using the competition load based on heart rate (HR). During 2 consecutive seasons, 12 professional cyclists (mean ± SEM: age 25 ± 1 years, height 175 ± 3 cm, body mass 65.9 ± 2.0 kg, and V(O2)max 78.5 ± 1.7 ml · kg(-1) · min(-1)) competed in 5-, 7-, and 21-day cycling races. The HR response and session RPE were measured during the races to calculate the competition load based on the training impulse of the HR (TRIMP(HR)) and RPE data (TRIMP(RPE)). The highest (p < 0.05) TRIMP(RPE) was observed in 21-day races. However, the higher (p < 0.05) TRIMP(HR) was found in 5- and 7-day races. When TRIMP(HR) and TRIMP(RPE) were normalized by competing distance, neither TRIMP(HR) · km(-1) nor TRIMP(RPE) · km(-1) was significantly different between the analyzed cycling races. We found significant (p < 0.001) correlations between TRIMP(HR) and TRIMP(RPE) (r = 0.75) and between TRIMP(HR) · km(-1) and TRIMP(RPE) · km(-1) (r = 0.90). In conclusion, this study showed that the session RPE can be used to quantify the competition load during professional cycling races. This method can be a useful and noninvasive tool for coaches to monitor and control the training load in cyclists.


Assuntos
Ciclismo/fisiologia , Ciclismo/psicologia , Frequência Cardíaca/fisiologia , Esforço Físico/fisiologia , Adulto , Humanos , Consumo de Oxigênio/fisiologia , Adulto Jovem
18.
J Clin Med ; 11(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35207262

RESUMO

The work performed by wildland firefighters (WFFs) is very demanding owing to the conditions in which they have to operate. It has been reported that these professionals walk long distances over unstable and steep terrain carrying heavy loads, handle tools manually and repeatedly and are subject to a high level of thermal stress. Under such conditions, the risk of developing chronic pain (CP) is high, although despite this, there are no available data pertaining to CP among WFFs, to the best of our knowledge. As such, the aim of this study is to describe CP in Spanish helitack crews, for which purpose 221 WFFs (203 men and 18 women) completed an online self-report questionnaire. Approximately 60% of WFFs reported suffering from CP, of which 45.5% had CP in more than one body region at the same time. Age and length of service were associated with the probability of suffering from CP. Likewise, the age and height of WFFs and weight of the protective equipment used increased the prevalence of CP. Lastly, gender and job position affected CP location, with women and forepersons reporting greater prevalence of CP in the lower limbs. To conclude, the results obtained suggest the major prevalence of CP among Spanish WFFs, with current data suggesting in turn the importance that age, stature, gender, length of service, weight of protective equipment and job position have on the prevalence and location of CP.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36231589

RESUMO

This study aimed to assess current perceptions of heat stress, heat strain, acclimatisation and recovery practices in wildland fire suppression. A total of 1459 wildfire and structural firefighters, all involved in wildland fire suppression, completed an 18-question survey. Most participants (81.3%) reported heat strain as one of the main risks faced during wildland firefighting. Thermal strain is considered an important risk for health and safety in wildland firefighting. The best-valued heat strain mitigation strategies were those traditionally recommended in wildland fire suppression: (i) an adequate work/rest ratio (79.0%), (ii) acclimatisation (71.6%), (iii) enhancing body ventilation by opening protective clothing or removing helmets or gloves (63.5%), and (iv) drinking water and food supplementation (52.1%). Despite these results, only 22% of the participants reported carrying out acclimatisation in the workplace. The vast majority of the respondents (87.4%) consider active cooling strategies (i.e., ice slurry ingestion, ice vests, etc.) impractical in combating heat strain during wildfire suppression. We identified a gap between knowledge about heat strain, its mitigation strategies and the level of actual implementation of these practices in the workplace. Our results highlight the need to improve heat strain management and implement operational directives for acclimatisation and active cooling interventions.


Assuntos
Água Potável , Bombeiros , Transtornos de Estresse por Calor , Incêndios Florestais , Temperatura Corporal , Transtornos de Estresse por Calor/prevenção & controle , Resposta ao Choque Térmico , Humanos , Gelo , América Latina
20.
J Strength Cond Res ; 25(2): 511-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20224447

RESUMO

This study analyzed and compared the exercise intensity exerted by Youth and Junior cyclists in single-day and stage races. Heart rate was measured during the races and categorized according to 3 intensity zones: Z1 (below the ventilatory threshold [VT]), Z2 (between the VT and the respiratory compensation threshold [RCT]), and Z3 (above the RCT). The training impulse (TRIMP) was calculated by multiplying the sum of the time spent in each zone by 1, 2, and 3, respectively. Time spent in Z1, Z2, and daily TRIMP were significantly higher (p < 0.05) in Junior than in Youth in both single-day races (21.6 ± 1.9 min vs. 14.8 ± 1.6 min, 55.4 ± 2.3 min vs. 34.7 ± 1.9 min, and 257 ± 6 vs. 194 ± 6, respectively) and stage races (49.2 ± 3.4 min vs. 23.5 ± 4.7 min, 51.2 ± 2.6 min vs. 35.3 ± 3.7 min, and 201 ± 10 vs. 147 ± 7, respectively). In Youth and Junior, time and percentage time spent in Z3 and daily TRIMP were also significantly higher (p < 0.05) in single-day races (39.0 ± 1.9 min, 40.2 ± 1.9% and 225 ± 7) than in stage races (13.9 ± 1.8 min, 15.2 ± 1.8% and 174 ± 8). In conclusion, the present study showed that races in both Youth and Junior categories are highly demanding and that their intensity and exercise load are related to the total race duration.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Adolescente , Limiar Anaeróbio/fisiologia , Comportamento Competitivo , Metabolismo Energético/fisiologia , Humanos , Masculino , Educação Física e Treinamento/métodos , Esforço Físico/fisiologia , Fatores de Tempo , Adulto Jovem
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