Relación del peso máximo con la fuerza aplicada y la potencia producida en un test creciente, en el ejercicio de press de banca plano con barra libre, en levantadores

Se evaluaron 9 levantadores que realizaron 2 test, en el ejercicio de press de banca plano con barra libre. Un test progresivo con pesos ligeros a máximos (TPR), y el test de una máxima repetición (1 MRD). Se midió la fuerza (f), velocidad (v) y potencia (p) con cada peso movilizado, se determinó el máximo peso desplazado en una única repetición (1 MR). Se observaron correlaciones significativas entre el valor de la 1 MR obtenida en el test de 1 MRPr y el de 1 MRD, entre la potencia máxima (absoluta y relativa al peso corporal) y la 1 MR absoluta y relativa al peso corporal. No se observaron diferencias significativas (p < 0,05) entre el valor de la 1 MR obtenida en el test progresivo (1 MRPr) y el alcanzado en el test de 1 MRD. Se acepta la aplicación del test progresivo (TPR) para determinar los niveles de f, v, p, el valor de la 1 MR en kg, así como localizar los porcentajes de peso, respecto al nivel de la 1 MR, en donde se alcanzan los valores más altos de potencia mecánica, y estimar las adaptaciones funcionales inducidas por los entrenamientos de fuerza

Relationship between shoulder pain and skin temperature measured by infrared thermography in a wheelchair propulsion test

Wheelchair Users (WCUs) depend on their upper extremities for their daily living. Therefore, it is not unusual to find that shoulder pain (SP) is a problem for WCUs and reduces their participation in sport and leisure activities

Relació del pes màxim amb la força aplicada i la potència produïda en un test creixent, en l’exercici de press de banca pla amb barra lliure, en aixecadors

Es van avaluar 9 aixecadors que van realitzar 2 tests, en l’exercici de press de banca pla amb barra lliure. Un test progressiu amb pesos lleugers a màxims (TPR), i el test d’una màxima repetició (1 MRD). Es va mesurar la força (f), la velocitat (v) i la potència (p) amb cada pes mobilitzat, es va determinar el pes màxim desplaçat en una única repetició (1 MR). Es van observar correlacions significatives entre el valor de la   1 MR obtinguda en el test d’1 MRPr i el d’1 MRD, entre la potència màxima (absoluta i relativa al pes corporal) i la  1 MR absoluta i relativa al pes corporal. No es van observar diferències significatives (p < 0,05) entre el valor de la 1 MR obtinguda en el test progressiu (1 MRPr) i l’assolit al test d’1 MRD. S’accepta l’aplicació del test progressiu (TPR) per determinar els nivells d’f, v, p, el valor de la 1 MR en kg, igual com per localitzar els percentatges de pes, respecte al nivell de la 1 MR, on s’aconsegueixen els valors més alts de potència mecànica, i estimar les adaptacions funcionals induïdes pels entrenaments de força

Bicarbonato ingestion has no ergogenic effect on consecutive all out sprint test in MWX elite cyclists

The aim of the present study was to examine the effect of sodium bicarbonate ingestion on consecutive "all out" sprint tests, analyzing the acid-base status and its influence on performance and perceived effort. Ten elite bicycle motocross (BMX) riders (20.7 ± 1.4 years, training experience 8-12 years) participated in this study which consisted of two trials. Each trial consisted of three consecutive Wingate tests (WTs) separated by 15 min recovery. Ninety minutes prior to exercise subjects ingested either NaHCO(3) (-) (0.3 g kg(-1) body weight) or placebo. Blood samples were collected for the assessment of blood acid-base status: bicarbonate concentration ([HCO(3) (-)]), pH, base excess (BE) and blood lactate concentration ([La(-)]). Performance variables of peak power (PP), mean power (MP), time to peak power and fatigue index were calculated for each sprint. Significant differences (p < 0.05) were observed in acid-base variables [pH before WT1: 7.47 ± 0.05 vs. 7.41 ± 0.03; [HCO(3) (-)] before WT1: 29.08 ± 2.27 vs. 22.85 ± 0.24 mmol L(-1) (bicarbonate vs. placebo conditions, respectively)], but there were not significant differences in performance variables between trials [PP WT1: 1,610 ± 373 vs. 1,599 ± 370 W; PP WT2: 1,548 ± 460 vs. 1,570 ± 428 W; PP WT3: 1,463 ± 361 vs. 1,519 ± 364 W. MP WT1: 809 ± 113 vs. 812 ± 108 W; MP WT2: 799 ± 135 vs. 799 ± 124 W; MP WT3: 762 ± 165 vs. 782 ± 118 W (bicarbonate vs. placebo conditions, respectively)]. Rating of perceived effort (RPE) was not influenced nor ratings of perceived readiness. Sodium bicarbonate ingestion modified significantly the blood acid-base balance, although the induced alkalosis did not improve the Wingate test performance, RPE and perceived readiness across three consecutive WTs in elite BMX cyclists

Strength plus Endurance Training and Individualized Diet Reduce Fat Mass in Overweight Subjects:A Randomized Clinical Trial

Studies with overweight people are a priority in order to observe the effect of the timing of intervention on pre-obesity people. The aim was to compare different physical activity programs plus an individualized hypocaloric diet on body composition in overweight subjects. A randomized controlled clinical trial was carried out in overweight adults with no history of relevant illness. Primary outcome was total fat mass (TFM). Participants were allocated into four activity programs with equal intensity and volume of exercise for 22 weeks: strength training (S), endurance training (E), strength + endurance training (SE), and 'adhering to physical activity recommendations' (C). Participants followed a diet with 25% less energy (50%-55% carbohydrates, 30%-35% fat) measured by accelerometer. Variables were assessed at baseline and at the end of the intervention. Body composition was measured by dual-energy X-ray absorptiometry. One hundred nineteen from 205 subjects were randomized in the four exercise groups (S = 30/E = 30/SE = 30/C = 29) and 84 participants (36 men/48 women) ended the intervention (S = 19/E = 25/SE = 22/C = 18). At the end of the experiment, all groups except C increased their total physical activity (S = 1159 ± 1740; E = 1625 ± 1790; SE = 1699 ± 2516; C = 724 ± 1979 MET-min/week). Using an ANOVA-test, improvements were observed in body weight (S = -4.6 ± 4.5; E = -6.6 ± 4.6; SE = -8.5 ± 2.8; C = -6.1 ± 5.6 kg, p = 0.059) and TFM (S = -4.24 ± 2.02; E = -4.74 ± 2.96; SE = -6.74 ± 3.27; C = -3.94 ± 4.18%; p < 0.05). The main conclusion was that there were no adverse events. Strength and endurance training with a balanced, individualized hypocaloric diet was the most effective at reducing weight loss and fat mass in overweight subjects. Trial registration: NCT01116856

The relative age effect on physical fitness in preschool children

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks’ λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers

Actividad física, ejercicio y deporte en la lucha contra la obesidad infantil y juvenil

El propósito del presente documento es proponer desde el grupo de expertos en ejercicio físico y salud de EXERNET (Red Española de Investigación en Ejercicio Físico y Salud) una serie de recomendaciones sobre la práctica de la actividad física y deportiva que a nivel individual, familiar e institucional ayuden a prevenir y tratar la obesidad infantil y juvenil, basadas en la evidencia científi ca actual