Heart rate cost of running in track estimates velocity associated with maximal oxygen uptake.

BACKGROUND: Running velocity associated with VO2max (vVO2max) is a parameter widely used for exercise prescription and is related to endurance performance. However, the vVO2max determination usually requires a maximal effort test and equipped laboratory for expired gas analysis, what make difficulty its assessment. OBJECTIVE: We aimed to test the validity of a simple method of vVO2max prediction through the heart rate cost of running (HRC) in a submaximal 6-min running test, both in treadmill and in a 400-meter track. METHODS: Male recreational runners (n = 16; 30.3 ±â€¯8.0 years; VO2max of 46.2 ±â€¯3.2 ml·kg-1·min-1) randomly underwent an incremental test in treadmill with gas analysis, and a 3000-m time trial in a track, to determine vVO2max. Before every maximal test, participants also performed a submaximal 6-min running (~85% HRmax), both in the treadmill and in a track, to assess HRC (bpm-1m·min-1) by dividing the submaximal running velocity by its respective HR. The vVO2max (km·h-1) was predicted by dividing the HRmax (bpm)/HRC (bpm-1m·min-1). RESULTS: No differences were verified (p > .05) among vVO2max determined both in the treadmill (13.8 ±â€¯0.9 km·h-1) and track (13.6 ±â€¯0.9 km·h-1) to those predicted by the HRC method both in treadmill (13.5 ±â€¯0.8 km·h-1) and track (13.6 ±â€¯1.0 km·h-1). The vVO2max measured directly with expired gas analysis was highly correlated with vVO2max estimated through HRC in treadmill and track (p < .05). Additionally, the intraclass correlation coefficient (ICC) and Bland-Altman technique revealed good agreement and reliability classified with substantial agreement [ICC = 0.673 (95% CI 0.064-0.886; p = .019)] and almost perfect agreement [ICC = 0.870 (95% CI 0.628-0.955 p = .0001)] between methods to identify vVO2max, respectively. CONCLUSION: A submaximal 6-min exercise test protocol to assess HRC of running was considered valid to estimate vVO2max of recreational runners both in treadmill and outdoor track.

Effect of self-paced active recovery and passive recovery on blood lactate removal following a 200 m freestyle swimming trial.

PURPOSE: The aim of this study was to investigate the effect of self-paced active recovery (AR) and passive recovery (PR) on blood lactate removal following a 200 m freestyle swimming trial. PATIENTS AND METHODS: Fourteen young swimmers (with a training frequency of 6-8 sessions per week) performed two maximal 200 m freestyle trials followed by 15 minutes of different recovery methods, on separate days. Recovery was performed with 15 minutes of passive rest or 5 minutes of passive rest and 10 minutes of self-paced AR. Performance variables (trial velocity and time), recovery variables (distance covered and AR velocity), and physiological variables (blood lactate production, blood lactate removal, and removal velocity) were assessed and compared. RESULTS: There was no difference between trial times in both conditions (PR: 125.86±7.92 s; AR: 125.71±8.21 s; p=0.752). AR velocity was 69.10±3.02% of 200 m freestyle trial velocity in AR. Blood lactate production was not different between conditions (PR: 8.82±2.47 mmol L-1; AR: 7.85±2.05 mmol L-1; p=0.069). However, blood lactate removal was higher in AR (PR: 1.76±1.70 mmol L-1; AR: 4.30±1.74 mmol L-1; p<0.001). The velocity of blood lactate removal was significantly higher in AR (PR: 0.18±0.17 mmol L-1 min-1; AR: 0.43±0.17 mmol L-1 min-1; p<0.001). CONCLUSION: Self-paced AR shows a higher velocity of blood lactate removal than PR. These data suggest that athletes may be able to choose the best recovery intensity themselves.

Effects of short-term plyometric training on physical fitness parameters in female futsal athletes.

[Purpose] To verify the effects of short-term plyometric training (PM) on body composition, flexibility and muscle power output in female Futsal athletes. [Subjects and Methods] Twenty female Futsal athletes (19.5 ± 1.29 years) equally and randomly divided into control and experimental groups were submitted to a sit-and-reach flexibility test, body composition measures and horizontal jump, at baseline and one day after the final training session. Both groups retained their training routines while only the experimental group participated in an additional 25 minutes of PM 2 times a week over 4 weeks. [Results] The experimental group showed higher values of flexibility and muscle power and lower body fat after the intervention in comparison to the baseline and control group. In addition, the effect size within-group after intervention indicated a moderate, large and very large effect for body fat, flexibility and muscle power, respectively. [Conclusion] These results show that plyometric training may be effective in reducing body fat and increasing flexibility and muscle power in female Futsal athletes. Thus, it may suggest that PM can be applied in the field of preventive physical therapy.

Diferentes ordens do exercício combinado: efeitos agudos de 24 horas sobre a pressão arterial de atletas / Different order of combined exercises: acute effects on 24-hour blood pressure in young men

Resumo Verificar as respostas de 24 horas da pressão arterial (PA) em jovens adultos após diferentes ordens de execução do exercício aeróbio (EA) e resistido (ER). Participarão do estudo dez homens saudáveis (22,6 ± 70,3; 3.7 anos ± 5,8 kg; 175,9 ± 5,8 centímetros). O estudo consistiu em quatro sessões experimentais realizadas de forma aleatórias: EA + ER (AR); ER + EA (RA); Circuito Concorrente (CC) e controle (CO). Todas as sessões tiveram a mesma duração e intensidade, EA: 15 min a 90% do limar de lactato mínimo indireto; ER: 15min a 90% de 12 RM com 12 repetições (seis exercícios). A PA foi medida antes, durante e 1 h (Microlife® BP3A1C) após a realização de exercícios em laboratório e 23 h durante as atividades diárias, utilizando a medição da pressão arterial ambulatorial (Dyna-MAPA®). A pressão arterial sistólica (PAS) no período de 24 horas e de vigília, e a diastólica (PAD), no período de 24 horas, o sono e de vigília, e a média da PA no período de vigília foram menores na sessão RA em comparação com a sessão CO apresentando um tamanho do efeito de moderado a alto (d de Cohen = -0,46 / -0,78). A área sob a curva da PAD na sessão AR foi menor do que na sessão CO no período de vigília (1004 ± 82 vs. 1065 ± 107; p < 0,047) e 24 h (1456 ± 103 vs 1528 ± 132 < 0,026) períodos. A sessão RA apresentou maiores pontos de redução da PA durante 24 horas em relação ao outros protocolos.(AU)

Abstract To verify 24-hour blood pressure (BP) responses in young adults after different orders of aerobic (AE) and resistance exercises (RE). Anaerobic threshold (AT) and strength (12 RM) were evaluated in ten healthy men (22.6 ± 3.7yrs; 70.3 ± 5.8 kg; 175.9 ± 5.8 cm). Four experimental sessions: Aerobic + Resistance (AR); Resistance + Aerobic (RA); Concurrent circuit (CC) and control day (CO) were randomly performed. All sessions had the same duration and intensity, AE: 15 min at 90% of AT; ER: 15 min at 90% of 12 RM with 12 reps (6 exercises). BP was measured before, during and 1 h (Microlife® BP3A1C) after performing exercises in the laboratory and 23 h during daily activities using ambulatory blood pressure measurement (Dyna-MAPA®). Systolic BP (SBP) in 24 h and awake periods, and Diastolic BP (DBP) in 24 h, sleep and awake periods, and Mean BP in awake period were lower in RA session compared with CO session with moderate to high effect size (d de Cohen = -0.46/-0.78). The DBP area under the curve in RA was lower than CO in awake (1004 ± 82 vs. 1065 ± 107; p < 0.047) and 24 h (1456 ± 103 vs. 1528 ± 132; p < 0.026) periods. The SBP delta were lower in RA at 0-1 h (-12.0 mmHg), 2-3h (-16.5 mmHg), 6-7 h (-19.4 mmHg) and 10-11 h (-13.0 mmHg) compared with CO; lower in AR at 4-5h (-19.2 mmHg) and 6-7 h (-20.2 mmHg) compared with CO; and lower in CC at 2-3h (-15.6 mmHg) and 6-7 h (-17.5 mmHg) compared with CO. The DBP was lower at 4-5 h (-14.0 mmHg) in RA compared with CO. After performing RA exercises, there were greater decreases in BP during 24 h in young adults.(AU)

High-intensity, but not moderate-intensity, exercise increases post-exercise rate of fat oxidation in type 2 diabetics.

BACKGROUND: Aerobic exercise is recommended for glycemic and weight control in type 2 diabetes (T2D), but exercise intensity that increase post-exercise fat oxidation has not been established yet. It is expected that high-intensity exercise induce higher absolute oxidations and rates of oxidation of CHO (during) and fat (after) in normoglycemic, but in hyperglycemic it is unclear. AIM: To compare the effects of exercise intensity on CHO and fat oxidation during and after exercise in individuals with T2D. METHODS: Eleven persons with T2D, randomly underwent three experimental sessions 72 hours apart: 1) 20 minute of high-intensity exercise (120% of lactate threshold (LT) - 120%LT), 2) 20 minute of moderate-intensity exercise (80% of LT - 80%LT), and 3) 20 minute of control session (CON) - no exercise was performed and the individuals remained seated during the whole time. Percentages of CHO and fat contribution and CHO and fat oxidation rate (mg/min) were analyzed during and after sessions. RESULTS: The rate of CHO oxidation during exercise was significantly higher during 120%LT in relation to 80%LT and CON (18.2 ± 5.6 vs. 9.5 ± 2.7 vs. 1.1 ± 0.4 mg∙min-1), the absolute rate of fat oxidation was significantly higher in 120%LT compared to 80%LT and CON during exercise (13.5 ± 3.3, 9.5 ± 2.2, and 0.7 ± 0.2 mg∙min-1, respectively, p < 0.05). During the post-exercise oxygen consumption recovery period, only the 120%LT had higher fat oxidation (94.5% vs. 68.1%, p < 0.05), when compared to CON. Both exercise sessions equally elicited a lowered glycaemia during the post-exercise period, but CHO oxidation was lower after 120%LT than CON (0.1 ± 0.2 vs. 0.9 ± 0.5 mg∙min-1, p < 0.05). CONCLUSIONS: Higher intensity elicited an elevated CHO oxidation rate during exercise and a higher percentage of fat utilization during the post-exercise recovery period compared to moderate-intensity exercise and control sessions. RELEVANCE FOR PATIENTS: High-intensity aerobic exercise, even of short duration, may benefit individuals with T2D on the substrate oxidation related to the body fat. Exercise can be an important tool for the prevention and management of T2D due to its effects on carbohydrate and fat metabolism, reduction of body fat, and control of blood glucose.

Critical velocity estimates lactate minimum velocity in youth runners

In order to investigate the validity of critical velocity (CV) as a noninvasive method to estimate the lactate minimum velocity (LMV), 25 youth runners underwent the following tests: 1) 3,000m running; 2) 1,600m running; 3) LMV test. The intensity of lactate minimum was defined as the velocity corresponding to the lowest blood lactate concentration during the LMV test. The CV was determined using the linear model, defined by the inclination of the regression line between distance and duration in the running tests of 1,600 and 3,000m. There was no significant difference (p=0.3055) between LMV and CV. In addition, both protocols presented a good agreement based on the small difference between means and the narrow levels of agreement, as well as a standard error of estimation classified as ideal. In conclusion, CV, as identified in this study, may be an alternative for noninvasive identification of LMV.

Com o objetivo de investigar a validade da velocidade crítica (VC) como método não invasivo de estimar a velocidade de lactato mínimo (VLM), 25 corredores adolescentes foram submetidos aos seguintes testes de corrida: 1) 3000m; 2) 1600m; 3) teste de VLM. A intensidade de lactato mínimo foi definida pela velocidade correspondente à menor concentração de lactato sanguíneo durante o teste de VLM. A VC foi determinada utilizando-se o modelo linear, sendo definida pela inclinação da reta de regressão distância-tempo nos testes de corrida de 1600 e 3000m. Não houve diferença significativa (p=0,3055) entre VLM e VC. Além disso, ambos os protocolos apresentaram uma boa concordância, baseado na pequena diferença entre as médias e nos estreitos limites de concordância, bem como um erro padrão de estimativa classificada como ideal. Em conclusão, a VC, como identificada no presente estudo, pode ser uma alternativa para identificação não invasiva da VLM.

Con el objetivo de investigar la validez de la velocidad crítica (VC) como un método no invasivo de estimar la velocidad de lactato mínimo (VLM), 25 corredores jóvenes realizaron las siguientes pruebas de carrera: 1) 3.000m; 2) 1.600m; 3) prueba de VLM. La intensidad de lactato mínimo fue definida como la velocidad correspondiente a la menor concentración de lactato sanguíneo durante la prueba de VLM. La VC fue determinada utilizando el modelo lineal, definido por la inclinación de la recta de regresión distancia-tiempo en las pruebas de carrera de 1.600 y 3.000m. No hubo diferencia significativa (p=0,3055) entre VLM y VC. Además, ambos protocolos tuvieron una buena concordancia, basado en la pequeña diferencia entre las medias y los estrechos límites de concordancia, así como un error padrón de la estimación clasificado como ideal. En conclusión, la VC, como identificado en este estudio, puede ser una alternativa no invasiva para la identificación de VLM.

Efeito da ordem do exercício concorrente na percepção de esforço em jovens atletas de jiu-jitsu / Alternations at the perceptual to different combined exercise in young athletes of jiu-jitsu

O objetivo do presente estudo foi verificar a resposta da percepção subjetiva de esforço (PSE) de jovens atletas de jiu-jitsu frente a diferentes ordens de aplicação do exercício aeróbio, resistido e concorrente (EC). Para isso a amostra foi composta por dez praticantes de jiu-jitsu, sexo masculino, aparentemente saudáveis (22.6 ± 3.7 anos; 70.3 ± 5.8kg; 175.9 ± 5.8 cm), após serem avaliados para aptidão aeróbia (limiar anaeróbio-LA) e força (12 repetições máximas–RM´s), participaram em dias distintos de 4 sessões experimentais, sendo: 1) Aeróbio+resistido (AR); 2) Resistido+aeróbio (RA); 3) Circuito concorrente exercício aeróbio/exercício resistido alternados (CC); 4) Controle (CO). As sessões tiveram a mesma duração e intensidades, sendo exercício aeróbio: 15 min a 90% LA e exercício resistido: 15 min a 90%-12RM´s com 12-rep (6 exercícios). A PSE durante o exercício aeróbio foi mensurada aos 5, 10 e 15 minutos, na sessão CC foi mensurada a cada 3 minutos e durante o exercício resistido foi mensurada após cada exercício em cada série. Foi utilizada a escala de Borg de 15 pontos (6 – 20) para o exercício aeróbio e a escala de OMIN para o exercício resistido. A PSE apresentou diferença significativa entre as sessões experimentais em relação à sessão RA (13.1 ± 2.3; 15.7 ± 2.9, p<0,001) aos 5 minutos para AR (9.4 ± 1.6, p<0,001) e CC (9.1 ± 1.3) e aos 15 minutos somente para a sessão AR (13 ± 2.4, p<0,001). Na exercício resistido a PSE apresentou diferença significativa intra sessões no AR (8.0 ± 1.4; 6.9 ± 1.1, p<0,005) e na sessão RA (6.5 ± 1.4; 5.4 ± 1.3, p<0,005) em dois exercícios (puxada e leg press) (p<0,005) respectivamente. Concluindo, a ordem de aplicação do exercício concorrente na mesma sessão, altera as respostas de PSE em jovens atletas de jiu-jitsu.

The aim of this study was to investigate the response of perceived exertion (PE) in young athletes jiu-jitsu against different orders of application of aerobic exercise, resistance and combined (EC) . The study included ten young male athletes (22.6 ± 3.7 years, 70.3 ± 5.8kg , 175.9 ± 5.8 cm) , after being assessed for aerobic fitness (anaerobic threshold - AT) and strength (12 repetitions maximum - RM ‘s). The tests consisted of four randomized protocols, the sessions consisted of aerobic exercise followed by resistance exercise, RE followed by aerobic exercise, circuit (CC) (RE and aerobic exercise alternating intermittently) and control session (CO) (without exercise). All sessions had the same duration and intensity, AE: 15min at 90% of AT; resistance exercise: 15min at 90% of 12RM with 12reps (6 exercises). The PSE during the aerobic exercise was measured at 5, 10 and 15 minutes, only the session CC was measured every 3 minutes and during the RE was measured after each exercise in each series . We used the Borg scale for the aerobic exercise and scale OMIN to the resistance exercise. The PE was different between the experimental sessions over the session RA (13.1±2.3; 15.7±2.9 , p < 0.001) at 5 minutes to AR (9.4±1.6; p < 0.001) and CC (9.1±1.3) and 15 minutes for session only AR (13 ± 2.4; p<0.001) and in the resistance exercise was distinct intra PSE sessions AR (8.0±1.4; 6.9±1.1 , p< 0.005) and session RA (6.5±1.4; 5.4±1.3 , p<0.005) in two exercises (leg press and pull) (p<0.005) respectively. Therefore, the order of application of combined exercise in the same workout session, modifies the response of PSE in aerobic exercise and resistance exercise in young adult athletes.

Ciclismo arriba del umbral de lactato es más efectivo que abajo para la liberación de óxido nítrico y reducción de la presión arterial después del ejercicio en individuos con diabetes tipo 2 / Ciclismo acima do limiar de lactato é mais efetivo que abaixo para liberação de óxido nítrico e redução da pressão arterial pós-exercício em indivíduos com diabetes tipo 2 / Cycling above rather than below lactate threshold is more effective for nitric oxide release and post-exercise blood pressure reduction in individuals with type-2 diabetes

The purposes of this study were to analyze and compare the effects of exercise performed in different intensities, above and below lactate threshold (LT) on post-exercise blood pressure (BP) and nitric oxide (NO) responses in individuals with type 2 diabetes (T2D). For this, 11 T2D underwent the following sessions: 1) control session; 2) 20-min of moderate cycling (80% LT); and 3) 20-min of high intensity cycling (120%LT) on a cycle ergometer. Plasma NO and BP measurements were carried out at rest and at 15 and 45 min of post-sessions. When compared to rest, only the exercise session performed at 120%LT elicited an increase of NO (from 7.2 to 9.5 µM, p<0.05), as well as a decrease in systolic BP (from 126.6±7.9 to 118.7±3.9 mmHg, p<0.05) during the post-exercise period. In conclusion, the results suggest that NO release and post-exercise BP decrease are intensity-dependent for individuals with T2D.

Os objetivos do presente estudo foram analisar e comparar os efeitos do exercício realizado em diferentes intensidades, acima e abaixo do limiar de lactato (LL), sobre a resposta da pressão arterial (PA) e óxido nítrico (NO) em indivíduos com diabetes tipo 2 (DM2). Para tanto, 11 DM2 foram submetidos às seguintes sessões: 1) sessão controle; 2) 20 min de exercício em cicloergômetro em intensidade moderada (80%LL); e 3) 20 min de exercício em cicloergômetro em alta intensidade (120%LL). O NO plasmático e as medidas de PA foram realizadas no repouso, bem como aos 15 e 45 min do período de recuperação de todas as sessões. Quando comparado ao período de repouso, somente a sessão de exercício realizado a 120%LL promoveu aumento do NO (de 7,2 para 9,5 µM, p<0,05) e, por conseguinte, uma diminuição na pressão arterial sistólica (de 126,6±7,9 para 118,7±3,9 mmHg, p<0,05) durante o período de recuperação pós-exercício. Em conclusão, os resultados sugerem que a liberação de NO e a diminuição da PA parecem ser intensidade-dependente para indivíduos com DM2.

Los objetivos del presente estudio fueron examinar y comparar los efectos del ejercicio realizado en diferentes intensidades, arriba y abajo del umbral de lactato (UL), sobre la respuesta de la presión arterial (PA) y el óxido nítrico (NO) en individuos con diabetes tipo 2 (DM2). Por lo tanto, 11 DM2 se sometieron las siguientes sesiones: 1) sesión control; 2) 20 min de ejercicio en cicloergómetro a una intensidad moderada (80%UL); y 3) 20 min de ejercicio en cicloergómetro a una intensidad alta (120%UL). El NO plasmático y las mediciones de la PA fueron realizados en reposo y en 15 y 45 min del período de recuperación para todas las sesiones. En comparación con el período de reposo, sólo la sesión de ejercicio realizado a 120%UL promovió aumento de NO (7,2 para 9,5 µM, p<0,05) y, por lo tanto, una disminución de la presión arterial sistólica (de 126,6±7,9 para 118,7±3,9 mmHg, p<0,05) durante el período de recuperación después del ejercicio. En conclusión, los resultados sugieren que la liberación de NO y la disminución de PA parece ser intensidad-dependiente para individuos con DM2.

Anthropometric and hemodynamic indicators of cardiovascular risk and associated factor with high blood pressure in miners / Indicadores antropométricos e hemodinâmicos de risco cardiovascular e fatores associados à pressão arterial elevada em mineradores

Obesity and hypertension are risk factors for cardiovascular diseases and their prevalence seems to vary according to profession. In this scenario, the aim of this study was to estimate the prevalence of cardiovascular risk factors in employees of a mining company and to identify associated factors with high blood pressure (BP). To this end, 197 volunteers (61.4% male) aged between 20 and 60, all employees of a mining company had their body mass index and BP measured. Excessive weight (overweight + obesity) and high BP values (pre-hypertension + hypertension) were observed in 76.1% and 46.1% of the sample, respectively; and the prevalence of pre-hypertensive individuals was higher (p <0.05) in men. The likelihood of having high BP was higher in males (11%), in those above than 40 years old (13%) and overweight (13%). In conclusion, a significant portion of the miners assessed is at risk for developing cardiovascular disease. Furthermore, measures against hypertension must be directed to male employees and those above than 40 years old. Overweight prevention and control are the main therapeutic measures to be adopted(AU)

A obesidade e a hipertensão arterial são tidas como fatores de risco para doenças cardiovasculares e a sua prevalência parece diferir de acordo com a atividade profissional. Desse modo, o objetivo do presente estudo foi estimar a prevalência de fatores de risco cardiovascular em funcionários de uma mineradora e verificar os fatores associados à pressão arterial (PA) elevada. Para tanto, 197 voluntários (61,4% homens) com idade entre 20 e 60 anos, todos funcionários de uma empresa de mineração, foram avaliados quanto ao índice de massa corporal e PA. O excesso de peso (sobrepeso + obesidade) e os valores pressóricos elevados (pré-hipertenso + hipertenso) foram observados em 76,1% e 46,1% da amostra, respectivamente, sendo a prevalência de pré-hipertensos maior (p <0,05) nos homens. A probabilidade de ter PA elevada foi maior no sexo masculino (11%), e naqueles com idade superior a 40 anos (13%) e com excesso de peso (13%). Em conclusão, uma parcela expressiva dos mineradores encontra-se em risco para o desenvolvimento de doenças cardiovasculares. Ademais, as medidas contra a hipertensão arterial devem ser direcionadas especialmente aos funcionários do sexo masculino e aqueles com idade superior a 40 anos, sendo a prevenção e o controle do excesso de peso as principais medidas terapêuticas a ser adotadas.(AU)

Indicadores antropométricos e hemodinâmicos de risco cardiovascular e fatores associados à pressão arterial elevada em mineradores / Anthropometric and hemodynamic indicators of cardiovascular risk andassociated factor with high blood pressure in miners

A obesidade e a hipertensão arterial são tidas como fatores de risco para doenças cardiovasculares e a sua prevalência parece diferir de acordo com a atividade profissional. Desse modo, o objetivo do presente estudo foi estimar a prevalência de fatores de risco cardiovascular em funcionários de uma mineradora e verificar os fatores associados à pressão arterial (PA) elevada. Para tanto, 197 voluntários (61,4% homens) com idade entre 20 e 60 anos, todos funcionários de uma empresa de mineração, foram avaliados quanto ao índice de massa corporal e PA. O excesso de peso (sobrepeso + obesidade) e os valores pressóricos elevados (pré-hipertenso + hipertenso) foram observados em 76,1% e 46,1% da amostra, respectivamente, sendo a prevalência de pré-hipertensos maior (p <0,05) nos homens. A probabilidade de ter PA elevada foi maior no sexo masculino (11%), e naqueles com idade superior a 40 anos (13%) e com excesso de peso (13%). Em conclusão, uma parcela expressiva dos mineradores encontra-se em risco para o desenvolvimento de doenças cardiovasculares. Ademais, as medidas contra a hipertensão arterial devem ser direcionadas especialmente aos funcionários do sexo masculino e aqueles com idade superior a 40 anos, sendo a prevenção e o controle do excesso de peso as principais medidas terapêuticas a ser adotadas.

Obesity and hypertension are risk factors for cardiovascular diseases and their prevalence seems to varyaccording to profession. In this scenario, the aim of this study was to estimate the prevalence of cardiovascularrisk factors in employees of a mining company and to identify associated factors with high blood pressure(BP). To this end, 197 volunteers (61.4% male) aged between 20 and 60, all employees of a mining companyhad their body mass index and BP measured. Excessive weight (overweight + obesity) and high BP values(pre-hypertension + hypertension) were observed in 76.1% and 46.1% of the sample, respectively; and theprevalence of pre-hypertensive individuals was higher (p <0.05) in men. The likelihood of having high BP washigher in males (11%), in those above than 40 years old (13%) and overweight (13%). In conclusion, a significantportion of the miners assessed is at risk for developing cardiovascular disease. Furthermore, measures againsthypertension must be directed to male employees and those above than 40 years old. Overweight preventionand control are the main therapeutic measures to be adopted.

Reprodutibilidade do protocolo de lactato mínimo com intensidade do esforço prévio individualizado pela PSE / Reliability of the lactate minimum protocolwith previous effort intensity individualized by RPE

Introdução: O protocolo de lactato mínimo (LM) é precedido de um esforço máximo para indução a hiperlactatemia. Objetivo: Verificar a reprodutibilidade de um teste de LM com indução à hiperlactatemia realizada em teste incremental com cargas individualizadas através da percepção subjetiva de esforço (PSE). Metodologia: A amostra foi composta por 20 estudantes fisicamente ativos (25,4 ± 4,1 anos; 14,1 ± 5,0 % gordura), submetidos a dois testes de LM com metodologia idêntica. A indução a hiperlactatemia foi realizada por um teste com quatro estágios, com duração de três minutos cada e cargas individualizadas pela PSE (níveis 10, 13, 16 e o último estágio 17-20 até a exaustão voluntária). Após oito minutos de recuperação o teste progressivo começou com carga inicial de 75 W e incrementos de 25 W a cada três minutos, até a exaustão. Resultados: As intensidades de LM 1 (155,0 ± 23,8 W) e LM 2 (157,5 ± 27,0 W) não diferiram estatisticamente (p = 0,795) e de uma maneira geral apresentaram boa reprodutibilidade (CCI = 0,79) e concordância [-2,5 W de média da diferença e ± 41,8 W de abas]. Conclusão: O teste de LM, com cargas para hiperlactatemia individualizadas pela PSE, se mostrou reprodutível em indivíduos fisicamente ativos.

The lactate minimum protocol (LM) is preceded by a maximum effort to induce hyperlactatemia. Objective: To verify the reliability of LM test with induced hyperlactatemia realized by exercise intensity individualized by the rating perceived effort (RPE). Methods: The sample was composed of 20 students, physically active (25.4 ± 4.1 years, 14.1 ± 5.0% fats) who were undertaken to two tests with identical methodology of LM. Induction of hyperlactatemia was performed by a test with four stages, lasting three minutes each, loads individualized by the PSE (levels 10, 13, 16 and 17-20 last stage until voluntary exhaustion). After eight minutes of recovery the progressive test started with initial load of 75W and 25W increments every 3 min until exhaustion. Results: The intensities of LM 1 (155.0 ± 23.8 W) and 2 (157.5 ± 27.0 W) did not differ statistically (p = 0.795) and showed good reliability (ICC = 0.79) and agreement [-2.5 W of mean difference and ± 41.8 W of bias]. Conclusion: The LM test, with loads for induction of hyperlactatemia individualized by the RPE, has shown to be reliable in physically active individuals.

Exercise lowers blood pressure in university professors during subsequent teaching and sleeping hours.

BACKGROUND: University professors are subjected to psychological stress that contributes to blood pressure (BP) reactivity and development of hypertension. The purpose of this study was to investigate the effects of exercise on BP in university professors during teaching and sleeping hours. METHODS: Twelve normotensive professors (42.2 ± 10.8 years, 74.2 ± 11.2 kg, 172.8 ± 10.4 cm, 20.1% ± 6.7% body fat) randomly underwent control (CONT) and exercise (EX30) sessions before initiating their daily activities. EX30 consisted of 30 minutes of cycling at 80%-85% of heart rate reserve. Ambulatory BP was monitored for 24 hours following both sessions. RESULTS: BP increased in comparison with pre-session resting values during teaching after CONT (P < 0.05) but not after EX30. Systolic, diastolic, and mean arterial BP showed a more pronounced nocturnal dip following EX30 (approximately -14.7, -12.7, and -9.6 mmHg, respectively) when compared with CONT (approximately -6, -5 and -3 mmHg). CONCLUSION: Exercise induced a BP reduction in university professors, with the main effects being observed during subsequent teaching and sleeping hours.

Avaliação da composição corporal e dos níveis de aptidão física de atletas de futsal classificados segundo a tipologia dos esquemas de gênero / Body composition and physical fitness level evaluation among futsal athletes classified into gender schemas typological groups / Body composition and physical fitness level evaluation among futsal athletes classified into gender schemas typological groups

INTRODUÇÃO: O autoconceito é uma estrutura formada por redes de esquemas cognitivos, dentre os quais se encontram os esquemas de gênero (esquema masculino e esquema feminino). De acordo com o Modelo Interativo, todos os indivíduos possuem os dois esquemas de gênero, dos quais resultam diferentes perfis psicológicos. OBJETIVO: Avaliar se atletas de futsal que diferem quanto à tipologia dos esquemas de gênero apresentam diferenças na composição corporal e nos níveis de aptidão física. MÉTODOS: A amostra inicial foi composta por 92 atletas do sexo masculino, classificados em grupos tipológicos de esquemas de gênero: Heteroesquemático Masculino (HM), Heteroesquemático Feminino (HF) e Isoesquemático (ISO). Para a classificação da amostra em grupos tipológicos foi utilizado o Inventário Masculino dos Esquemas de Gênero do Autoconceito (IMEGA). Foram utilizados os testes Squat Jump, Counter Movement Jump e Running Anaerobic Sprint Test; para mensurar, respectivamente, força explosiva e potência anaeróbia. Para a análise dos resultados foram utilizadas ANOVA One Way, ANOVA Mista e MANOVA. RESULTADOS: Os resultados demonstraram que os grupos HM, ISO e HF não apresentaram diferenças quanto à composição corporal, mas que os HM apresentaram índice médio de fadiga maior do que os grupos ISO e HF. Na avaliação dos seis tiros executados pelos atletas, observou-se que o grupo HM apresentou maior variação entre a potência máxima inicial e a final, quando comparado aos demais grupos. CONCLUSÃO: Os resultados permitem concluir que os diferentes perfis psicológicos adéquam-se melhor ao desempenho de determinadas posições do jogo e/ou a determinadas situações específicas durante o jogo.

INTRODUCTION: Self-concept is a structure formed by cognitive schemas, among of these there are gender schemas (male and female schemas). According to the Interactive Model, all individuals are composed of both schemas resulting in different psychological profile. OBJECTIVE: This study aimed to evaluate if futsal athletes who differ in gender schemas typological groups present differences in body composition and physical fitness level. METHOD: The initial sample was composed of 92 male athletes, who were classified in the following gender schema typological group: Male Heteroshematic (MH), Female Heteroshematic (FH) and Isoshematic (ISO). In order to classify the sample in typological groups, the Male Inventory of the Self-Concept's Gender Schemas (IMEGA) was used. The Squat Jump, Counter Movement Jump and Running Anaerobic Sprint Tests were used to assess explosive power and anaerobic capacity, respectively. The results were analyzed with Analysis of Variance (ANOVA): One Way, Mixed and Manova. RESULTS: The results showed no differences in body composition, but MH presented more fatigue than the ISO and FH groups. In the assessment of six sprints executed by the athletes, it was observed that MH presented more variation between the initial and final maximum power, when compared with the other groups. CONCLUSION: These results lead to the conclusion that different psychological profiles adapt better to some game positions performance and/or to some specific situations during the game. Finally, it is suggested that the psychological profile must be used as a criterion in the selection of the athletes, considering also physiological and technical factors.

Identificação do lactato mínimo de corredores adolescentes em teste de pista de três estágios incrementais / Lactate minimum identification in youth runners through a track test of tree incremental stages

OBJETIVO: Analisar a possibilidade de se determinar a velocidade de lactato mínimo (LM) em corredores adolescentes utilizando-se apenas três estágios incrementais. MÉTODOS: Onze indivíduos (13,7 ± 1,0 anos; 47,3 ± 12,1kg; 160,0 ± 1,0cm; 18,3 ± 1,8kg/m²) realizaram três testes de corrida em pista de atletismo em dias distintos: 1) desempenho de 3.000m (Vm3.000); 2) teste de LM que consistiu de um sprint de 500m para indução a hiperlactatemia, seguido de 10min de recuperação e seis séries de 800m em intensidades de 83, 86, 89, 92, 95 e 98 por cento da Vm3.000; 3) teste de LM com três estágios (LMp3) semelhante ao protocolo anterior, porém, com três séries de 800m em intensidades de 83, 89 e 98 por cento da Vm3.000. Durante o primeiro minuto de recuperação entre os estágios dos testes dois e três foram coletadas amostras de sangue para dosagem de lactato sanguíneo. Para determinação do LM foram empregadas: a) inspeção visual (LM) e b) função polinomial de segunda ordem para identificar o LM em seis estágios (LMp) e três estágios (LMp3). RESULTADOS: ANOVA demonstrou não haver diferenças entre as velocidades de lactato mínimo (m.min-1) identificadas pelos diferentes métodos (LM = 221,7 ± 15,4 vs. LMp = 227,1 ± 10,8 vs. LMp3 = 224,1 ± 11,2;). Altas correlações foram observadas entre os protocolos estudados e destes com a Vm3.000 (p < 0,01). CONCLUSÃO: Foi possível identificar a velocidade de corrida correspondente ao LM em adolescentes mesmo utilizando-se de apenas três estágios incrementais (LMp3).

OBJECTIVE: To analyze the possibility of determining the lactate minimum (LM) velocity in prepubertal runners applying only three incremental stages. METHODS: Eleven teens (13.7 ± 1.0 years; 47.3 ± 12.1 kg; 160.0 ± 1.0 cm; 18.3 ± 1.8 kg/m²) performed three run tests on athletic track field on different days: 1) performance at 3000m (Vm3000) 2) LM test consisting of a 500m sprint for hyperlactatemia induction, followed by 10min of recovery and six sets of 800m at intensities of 83, 86, 89, 92, 95 and 98 percent of Vm3000, 3) LM test with threestage (LMp3) similarly to the previous protocol; however, with only three sets of 800m at intensities of 83, 89 and 98 percent of Vm3000. During the first recovery minute between the second and third test stages, blood samples were collected in order to measure blood lactate. The following criteria were used to determine LM: a) visual inspection (LM), b) polynomial function of second order to LM six stages (LMp) and to three stages (LMp3). RESULTS: ANOVA showed no differences between speeds (m.min-1) identified in the studied methods (LM = 221.7 ± 15.4 vs. LMp = 227.1 ± 10.8 vs. LMp3 = 224.1 ± 11.2). High correlations were observed between the studied protocols and between these protocols and the Vm3000 (p <0.01). CONCLUSION: It was possible to identify the velocity corresponding to the LM in youth runners even when applying only three incremental stages for identification of the LM intensity (LMp3).

Validade de equações de predição em estimar o VO2max de brasileiros jovens a partir do desempenho em corrida de 1.600m / Predictive equations validity in estimating the VO2max of young Brazilians from performance in a 1600 m run

O objetivo deste estudo foi analisar a validade da equação proposta por Cureton et al. (1995) "VO2peak = -8.41 (MRW) + 0.34 (MRW)2 + 0.21 (Age x Gender) -0.84 (BMI) + 108.94" em estimar o VO2max de brasileiros jovens a partir de um teste de 1.600 metros, e sugerir uma equação de predição que seja específica para essa população. Participaram do estudo 30 homens fisicamente ativos (23 ± 3,1anos; 74,8 ± 5,8kg; 1,78 ± 0,05m; 49,8 ± 6,5mL.kg-Õ.min-1) que foram submetidos a um teste incremental máximo (TI) em esteira e um teste de desempenho em corrida de 1.600 metros. Os indivíduos foram divididos em dois grupos: G1 - para gerar uma equação de predição específica para VO2max de brasileiros jovens e G2 - para aplicar ambas as equações a fim de analisar suas validades. Diferenças estatisticamente significativas foram observadas entre o VO2max determinado diretamente no TI (50,1 ± 7,1mL.kg-Õ.min-Õ) e os valores de VO2max obtidos pela equação proposta por Cureton et al. (44,2 ± 6,5mL.kg-Õ.min-Õ) com baixa correlação entre elas (r = 0,21). A relação entre VO2max e velocidade em corrida de 1.600m obtidos no G1 resultou na seguinte equação de predição: (VO2max = 0,177 * 1.600Vm(m.min-1) + 8,101). Quando essa nova equação foi aplicada nos participantes do G2, o VO2max predito (50,1 ± 7,2mL.kg-Õ.min-Õ) não diferiu do VO2max determinado diretamente (50,1 ± 7,1mL.kg-Õ.min-Õ) com alta correlação entre eles (r = 0,81). Assim, concluímos que a equação de Cureton et al. (1995), elaborada a partir de resultados de amostra norte-americana, subestimou o VO2max de brasileiros jovens e fisicamente ativos. Por outro lado, a equação proposta no presente estudo se mostrou válida para estimar o VO2max através do teste de desempenho de 1.600 metros para a população estudada.

The aim of the present study was to analyze the validity of predictive equation proposed by Cureton et al. (1995) for VO2peak = -8.41 (MRW) + 0.34 (MRW) 2 + 0.21 (Age x Gender) -0.84 (BMI) + 108.94" on estimating the VO2max of young Brazilians from a 1600-m running performance, and to suggest a predictive equation specific for this population. 30 physically active young men (23±3.1age; 74.8±5.8kg; 1.78±0.05m; 49.8±6.5mL.kg-Õ.min-1) who were submitted to an incremental exercise test (IT) on treadmill until exhaustion with gas analysis participated in this study. Subjects also performed a 1600-m running track test as fast as possible. The volunteers were randomly sorted in two groups: G1 - to generate a specific predictive equation for VO2max, and G2 - to apply both predictive equations (actual and from Cureton et al.) to evaluate their validity on estimating VO2max in a Brazilian population sample. Significant differences were observed between VO2max directly identified on IT through gas analysis (50.1±7.1 mL.kg-Õ.min-Õ) in relation to the results obtained by the predictive equation proposed by Cureton et al. (1995) (44.2±6.5mL.kg-Õ.min-Õ) with a weak relationship between them (r = 0.21). The relationship between the VO2max on IT and the running velocity on 1600-m as obtained for G1 resulted in the following predictive equation: (VO2max = 0.177*1600Vm(m.min-1) + 8,101). When this new equation was applied on the participants of G2, the predicted VO2max (50.1±7.2mL.kg-Õ.min-Õ) did not differ from VO2max determined directly on IT (50.1±7.1mL.kg-Õ.min-Õ) with a high correlation between them (r = 0.81). Thus, it was concluded that the Cureton et al. predictive equation developed with a North Americanpopulation sample as grounding, underestimated the VO2max of physically active young Brazilians. On the other hand, the predictive equation proposed on the present study was considered valid for this purpose through the 1600-m running performance...

Indirect assessment of lactate minimum and maximal blood lactate steady-state intensity for physically active individuals.

An indirect assessment of the running velocity corresponding to lactate minimum (LMind) and its validity to estimate the maximal blood lactate steady state (MLSS) were analyzed in 22 physically active men (24.6 +/- 4.1 years, 72.6 +/- 8.0 kg, 1.75 +/- 0.1 m, 11.9 +/- 3.7% body fat). The participants were allocated into 2 different groups (G1 and G2). The running velocities (m x min) corresponding to the 1600-m time trial (1600 mV) and lactate minimum (LM) were determined for G1 (n = 12), whereas the G2 participants (n = 10) had their MLSS identified in addition to the 1600 mV and LM tests. The LM test consisted of a 150-m sprint to elevate blood lactate ([lac]) followed by 10 minutes of recovery and then 6 x 800-m at 78, 81, 84, 87, 90, and 93% of 1600 mV, with the velocity corresponding to the lowest [lac] (YSI 2700S) identified in the LM test. The relationship between 1600 mV and LM values for G1 yielded the following equation for indirect assessment of LM velocity: LMind (m x min) = (0.7507 x 1600 mV) + 21.575. The validity of the LMind was tested in the G2 participants by comparing its results with those of the MLSS. The MLSS was identified among 3-4 constant-intensity sessions by considering the highest running velocity for which a [lac] variation was not higher than 0.05 mM x min. No differences were observed for the LM (200.7 +/- 16.8 m x min), LMind (200.8 +/- 15.1 m x min), and MLSS (201.0 +/- 15.6 m x min) for G2, and there was high correlation and agreement among parameters. The LMind was considered valid for estimating LM and MLSS values if applied to physically active individuals with characteristics similar to those of the present study; thus, it is a practical and economical alternative for trainers who cannot directly determine MLSS.

Maximal lactate steady-state prediction through quadratic modeling of selected stages of the lactate minimum test.

In this study, we compared the maximal lactate steady state (MLSS) with lactate minimal (LM) intensities determined visually and through a quadratic polynomial function of selected stages of LM test. Eleven male recreational cyclists (27.7 +/- 4.5 years, 175.7 +/- 5.6 cm, 69.5 +/- 10.8 kg, and 12.0 +/- 5.5% body fat) performed one LM test under previous induction of hyperlactaemia with an initial intensity of 75 W with 30-W increments every 3 minutes with blood lactate concentration (HLa) and rating of perceived exertion (RPE) measurements. The LM intensity was determined visually (VLM) and by modeling the lactate response through polynomial function by using: 1) all stages (LMP); 2) the first stage, the stage corresponding to RPE-13 and the last stage/exhaustion (LMP3max); 3) the three lowest lactate concentration stages (LMP3adj); and 4) the initial, RPE-13, and RPE-16 stages (LMP3sub). The MLSS was determined as the highest intensity at a variation not greater than 0.05 mmol.l.min of HLa during the last 20 minutes of a 30-minute exercise session. The MLSS (204.0 +/- 16.0 W), VLM (198.6 +/- 15.2 W), LMP3adj (190.4 +/- 12.9 W), and LMP3sub (192.1 +/- 27.2 W) were not different, well correlated, and in agreement to each other. In conclusion, the polynomial modeling of HLa response to three submaximal stages produced exercise intensities that did not differ from MLSS.

Polynomial adjustment as a new technique for determination of lactate minimum velocity with blood sampling reduction

The purpose of this study was to analyze the possibility of identifying the lactate minimum velocity (LM) andestimating the maximal lactate steady state intensity (MLSS) by applying a polynomial function to just three stages of the LM test. Seventeen physically active males (24.1 ± 4.0 years; 23.8 ±2.2kg.m2(-1) BMI; 11.7 ± 3.8% body fat) performed: 1) a 1600mtime trial (1600mV); 2) a 150m sprint to induce hyperlactatemia, and then an incremental test (InT) consisting of 6 x 800m at intensities of 78, 81, 84, 87, 90 and 93% of 1600mV; 3) 2 to 3 sessions of constant 30 min running tests to identify MLSS. Blood lactate [lac] was determined by an electrochemical method (YSI - 2700 SELECT). The LM was identifi ed visually (LMv) as well by applying polynomial function to the [lac] responses at all 6 stages (LMp), to the 1st, 3rd and 5th stages (LMp135), to the 1st, 3rd and 6th stages (LMp136) and to the 1st, 4th and 6th stages (LMp146) of InT. The ANOVA detected no differencesbetween the velocities (m.min-1) identifi ed by LMv (196.0 ± 17.8) LMp (198.0 ± 17.6), LMp135 (197.7 ± 17.6), LMp136 (200.0 ±17.2), LMp146 (199,7 ± 18,1) and MLSS (198.7 ±16.6) (p>0.05), with a high correlation among each other (p<0.01). The polynomial function identifi ed LM even when applied to just 3 stages of the incremental test, enabling for prediction of MLSS intensity with a reduced number of blood samples being collected during testing.

O propósito do estudo foi analisar a possibilidade de identifi cação da velocidade de lactato mínimo (LM) e dese estimar a máxima fase estável de lactato (MFEL), aplicando a função polinomial de segunda ordem a partir de apenas três estágios do teste do LM. Participaram do estudo 17 homens fi sicamente ativos (24,1 ± 4.0 anos; 23,8 ± 2,2kg.m2(-1) IMC; 11,7 ± 3,8% gordura corporal) realizaram: 1) corrida de 1600m no menor tempo possível para cálculo da velocidademédia (1600mV); 2) ôsprintõ de 150m para indução de hiperlactatemia e um teste incremental (Tin) consistindo de 6x800m a intensidades de 78, 81, 84, 87, 90 e 93% do 1600mV; 3) 2 a 3 sessões de 30 min de corrida em intensidade constante para determinação da MFEL. O lactato sanguíneo [lac] foi determinado pelo método eletroenzimático (YSI - 2700 SELECT). O LM foi identifi cado visualmente (LMv) bem como aplicando ajuste polinomial usando todos os 6 estágios (LMp), o 1°, 3°e 5° estágios (LMp135), o 1°, 3° e 6° estágios (LMp136) e o 1°, 4° e 6° estágios (LMp146) do test incremental. A ANOVA evidenciou não haver diferenças entre as velocidades (m.min-1) identifi cadas pelo LMv (196,0 ± 17,8), LMp (198,0 ± 17,6),LMp135 (197,7 ± 17,6), LMp136 (200,0 ±17,2), LMp146 (199,7 ±18,1) e MFEL (198,7 ± 16,6) (p>0,05), e alta correlação entre os métodos estudados (p<0,01). A identifi cação do LM aplicando a função polinomial em apenas 3 estágios, demonstrouser válida em estimar a MFEL e útil por possibilitar redução no número de coletas de [lac] durante o teste...