A Short-Term Resistance Training Circuit Improved Antioxidants in Sedentary Adults with Down Syndrome.

Previous studies have found aerobic training improved oxidative damage in people with Down syndrome (DS). However, there is a lack of information regarding the influence of resistance training on redox imbalance in this population. Accordingly, this study was conducted to determine the effect of resistance training (RT) on antioxidant defence system in sedentary adults with DS. Thirty-six male adults with DS were recruited through different community support groups. Eighteen were randomly assigned to perform a circuit RT program with 6 stations, 3 days/week for 12 weeks. Plasma total antioxidant status (TAS), reduced glutathione (GHS), ascorbate, serum α-tocopherol, and erythrocyte glutathione reductase activity were assessed. Plasma malondialdehyde (MDA) and carbonyl groups (CG) were assessed as markers of oxidative damage. Muscle strength was also measured. Dynamic torque of knee extensors and flexors as well as maximal handgrip strength was significantly improved after the completion of the training program. Plasma levels of TAS and erythrocyte glutathione reductase (GR) activity were significantly increased. Conversely, MDA and CG levels were significantly reduced. It was concluded RT improved antioxidant defence system and reduced oxidative damage in adults with DS. Further, long-term studies are required to determine whether the increased antioxidant system may improve clinical outcomes of adults with DS.

The complex relationship between effort and heart rate: a hint from dynamic analysis.

OBJECTIVE: Dynamic analysis can be used to study the changes of self-regulated biological processes driven by external stimuli. Recently, the changes of heart rate during effort tests has successfully been adjusted using a simple first-order differential equation model driven by body power expenditure. Although this approach produces valid estimates and yields pertinent indices for the analysis of such measurements, it suffers from an inability to model the saturation of the heart-rate increase at high power expenditures and the change of heart-rate equilibrium following effort. APPROACH: We propose a new analysis allowing the estimation of changes of the heart rate in response to effort (gain) as a function of the power expenditure value. MAIN RESULTS: When applied to the measured heart rates of 30 amateur athletes performing a maximum graded-effort treadmill test, the proposed model was able to predict 99% of the heart rate change measured during exercise. The estimated gains decreased with a power increase above the first ventilatory threshold. This trend was stronger above the second ventilatory threshold and was strongly correlated with the maximum oxygen consumption. SIGNIFICANCE: The proposed approach yields a highly precise model of heart rate dynamics during variable effort that reflects the changes of metabolic energy systems at play during exercise.

Validity of dynamical analysis to characterize heart rate and oxygen consumption during effort tests.

Performance is usually assessed by simple indices stemming from cardiac and respiratory data measured during graded exercise test. The goal of this study is to characterize the indices produced by a dynamical analysis of HR and VO2 for different effort test protocols, and to estimate the construct validity of these new dynamical indices by testing their links with their standard counterparts. Therefore, two groups of 32 and 14 athletes from two different cohorts performed two different graded exercise testing before and after a period of training or deconditioning. Heart rate (HR) and oxygen consumption (VO2) were measured. The new dynamical indices were the value without effort, the characteristic time and the amplitude (gain) of the HR and VO2 response to the effort. The gain of HR was moderately to strongly associated with other performance indices, while the gain for VO2 increased with training and decreased with deconditioning with an effect size slightly higher than VO2 max. Dynamical analysis performed on the first 2/3 of the effort tests showed similar patterns than the analysis of the entire effort tests, which could be useful to assess individuals who cannot perform full effort tests. In conclusion, the dynamical analysis of HR and VO2 obtained during effort test, especially through the estimation of the gain, provides a good characterization of physical performance, robust to less stringent effort test conditions.

The Effects of Aquatic Plyometric Training on Repeated Jumps, Drop Jumps and Muscle Damage.

The purpose of this study was to compare the effects of land- vs. aquatic based plyometric training programs on the drop jump, repeated jump performance and muscle damage. Sixty-five male students were randomly assigned to one of 3 groups: aquatic plyometric training group (APT), plyometric training group (PT) and control group (CG). Both experimental groups trained twice a week for 10 weeks performing the same number of sets and total jumps. The following variables were measured prior to, halfway through and after the training programs: creatine kinase (CK) concentration, maximal height during a drop jump from the height of 30 (DJ30) and 50 cm (DJ50), and mean height during a repeated vertical jump test (RJ). The training program resulted in a significant increase (P<0.01-0.001) in RJ, DJ30, and DJ50 for PT, whereas neither APT nor CG reached any significant improvement APT showed likely/possibly improvements on DJ30 and DJ50, respectively. Greater intra-group Effect Size in CK was found for PT when compared to APT. In conclusion, although APT seems to be a safe alternative method for reducing the stress produced on the musculoskeletal system by plyometric training, PT produced greater gains on reactive jumps performance than APT.

Salivary testosterone and immunoglobulin A were increased by resistance training in adults with Down syndrome.

This study was designed to assess the influence of resistance training on salivary immunoglobulin A (IgA) levels and hormone profile in sedentary adults with Down syndrome (DS). A total of 40 male adults with DS were recruited for the trial through different community support groups for people with intellectual disabilities. All participants had medical approval for participation in physical activity. Twenty-four adults were randomly assigned to perform resistance training in a circuit with six stations, 3 days per week for 12 weeks. Training intensity was based on functioning in the eight-repetition maximum (8RM) test for each exercise. The control group included 16 age-, gender-, and BMI-matched adults with DS. Salivary IgA, testosterone, and cortisol levels were measured by ELISA. Work task performance was assessed using the repetitive weighted-box-stacking test. Resistance training significantly increased salivary IgA concentration (P=0.0120; d=0.94) and testosterone levels (P=0.0088; d=1.57) in the exercising group. Furthermore, it also improved work task performance. No changes were seen in the controls who had not exercised. In conclusion, a short-term resistance training protocol improved mucosal immunity response as well as salivary testosterone levels in sedentary adults with DS.

Ecuación predictora de masa grasa corporal en deportistas con lesión medular crónica: estudio piloto / Predictive equation of body fat percentage in athletes with chronic spinal cord injury: a pilot study

La determinación del porcentaje de masa grasa en pacientes con lesión medular crónica (LMC) resulta de interés por la alta morbimortalidad cardiovascular que presenta este grupo. En el caso de deportistas, además, permitiría optimizar su rendimiento deportivo. Por consiguiente, el presente estudio se planteó como primer objetivo comparar diferentes métodos de estudio del porcentaje de masa grasa de deportistas con LMC. Y como objetivo secundario, identificar alguna ecuación que permita predecir los niveles de masa grasa de manera más económica, sencilla, rápida y no invasiva. Se diseño un estudio observacional y transversal en el que participaron voluntariamente 8 deportistas varones con LMC a nivel o por debajo de T5 que compiten a nivel nacional. El porcentaje de masa grasa corporal de los participantes se determinó mediante tres metodologías: densitometría (DEXA), antropometría convencional (Ecuación de Siri) e impedancia bioeléctrica (BIA). Este protocolo fue aprobado por un Comité de Ética Institucional. El porcentaje de masa grasa presentado por jugadores de baloncesto en silla de ruedas tras someterse al método de referencia (DEXA) fue del 28,76±9,16%. El análisis de concordancia de Bland-Altman entre métodos sugiere que tanto la antropometría convencional como la BIA subestiman el porcentaje de masa grasa de deportistas con LMC. la ecuación de predicción obtenida fue: Masa Grasa (%)= 1,9197 (pliegue tríceps (mm)) + 6,5063. Tanto las técnicas antropométricas convencionales como la propia BIA subestiman la masa grasa en deportistas con LMC. Asimismo se ha identificado una ecuación de regresión para la predicción del porcentaje de masa grasa de bajo coste y aplicable en cualquier entorno.

The assessment of fat mass (FM) is of great interest for people with chronic spinal cord injury (SCI) given that morbidity and mortality from cardiovascular disease are greater and occur earlier in this group. Furthermore, it may play a key role improving physical performance in athletes with SCI. For the reasons already mentioned, the current study was designed to compare different methods for assessing FM in athletes with SCI. A secondary objective was to identify a predictive equation for FM in this group that is easily reproducible elsewhere. A total of 8 male athletes with complete SCI at or below the 5th thoracic level (T5) competing in a national league volunteered for this study. The percentage of FM was assessed by three different methods: conventional anthropometry (Siri equation), bioelectrical impedance analysis (BIA) and densitometry (DEXA). This research was conducted in full accordance with ethical principles, including the World Medical Association Declaration of Helsinki (version, 2002). Furthermore, the present protocol was approved by an Institutional Ethics Committee. Mean percentage of FM assessed by DXA was 28.76±9.16%. Moreover, Bland-Altman plots suggested conventional anthropometry and BIA underestimated fat mass percentage in this group. Lastly, a predictive equation for fat mass was established as follows: FM (%)=1.9197 (triceps skinfold thickness (mm))+6.5063. It was concluded that both conventional anthropometry and BIA underestimated fat mass in athletes with chronic SCI. Furthermore, a predictive equation of fat mass was recommended for this group due to its low cost and wide availability in any clinical setting.

Detraining in young soccer players.

BACKGROUND: Two types of detraining can be described: short-term detraining with a period of less than 4 weeks, and long-term detraining (period longer than 4 weeks). The purpose of this study is to verify the presence and eventually the magnitude of physiological cardiorespiratory changes in young team sport players after a period of long-term detraining. METHODS: Fourteen young soccer players (15 ± 1 year) were studied with two incremental tests at the end of the regular season and after a six-week total break period from training activities. Physiological variables were evaluated: heart rate (HR), oxygen uptake (VO2), volume of ventilation (VE), aerobic (VA) and anaerobic (Van) running speed at thresholds and maximum effort were recorded. RESULTS: This study shows the magnitude of the physiological changes in young players after a period of long-term detraining. The results showed significant decreases at the end of the detraining period of VO2 at VA of 22.7% (44.54 ± 4.56 vs. 34.41 ± 4.57 mL/kg/min, P<0.05), of 25.8% of VO2 at VAn (54.60 ± 5.81 vs. 40.48 ± 5.07 mL/kg/min, P<0.05) and of 21.2% in VO2 max (62.83 ± 5.77 vs. 49.46 ± 6.51 mL/kg/min, P<0.05). Speed at VA (11.5 ± 0.96 vs. 10.7 ± 0.97 km/h; P<0.05), speed at VAn (15.3 ± 1.05 vs. 14.2 ± 1.48 km/h; P<0.05), peak running speed (18.8 ± 1.20 vs. 17.2 ± 1.1 km/h; P<0.05). CONCLUSION: It is likely that alteration of metabolic parameters may significantly affect the range of physical condition and especially, aerobic-anaerobic resistance and maintenance training would be advisable in young athletes during the transition period. Given the relevance of worsening demonstrated by our data, coaches should avoid very long periods of complete rest (no more than 15 days) at the end of the season.

Correlaciones entre marcadores de grasa abdominal obtenidos por densitometría y técnicas antropométricas convencionales en mujeres postmenopausicas con síndrome metabólico / Correlations between markers of abdominal fat obtained by dxa and anthropometric conventional techniques in postmenopausal women with metabolic syndrome

El presente estudio pretende identificar correlaciones estadísticamente significativas entre parámetros de masa grasa abdominal obtenidos por densitometría (DXA) y otros de tipo cineantropométrico (índices de distribución de masa grasa) y bioquímico (perfil lipídico) en mujeres postmenopausicas con síndrome metabólico. Se diseño un estudio de cohortes histórico que incluyó a un total de 1326 mujeres post-menopausicas con edad > 45 años que se habían sometido rutinariamente a DXA para conocer su densidad mineral ósea entre Enero de 2006 y Enero de 2011. Se utilizó un DXA tipo Lunar DPX-L para determinar la masa grasa abdominal en las regiones de interés L1-L4 y L3-L4. Además del DXA, se obtuvo de cada participante la correspondiente anamnesis, bioquímica, tensión arterial e índices de distribución de masa grasa mediante técnicas antropométricas convencionales. Se utilizó la clasificación NCEP-ATP-III para el diagnóstico de síndrome metabólico. Este protocolo fue aprobado por un Comité de Ética Institucional. La mayor fuerza de asociación se estableció entre el porcentaje de masa grasa L1-L4 obtenido por DXA y el perímetro de la cintura (r= 0,77; p= 0,0016) además de con colesterol-HDL (r= -0,58; p= 0,0290). Finalmente se concluye que el perímetro de la cintura y los niveles de colesterol-HDL podrían recomendarse como predictores del comportamiento de la masa grasa abdominal de regiones de interés L1-L4 y L3-L4 obtenidas por DXA en mujeres postmenopausicas con síndrome metabólico.

The current study was conducted to identify potential correlations between abdominal fat mass obtained by DXA and several parameters obtained by anthropometric conventional techniques as well as lipid profile in postmenopausal women with MS. This historical cohort study included a total of 1326 postmenopausal women aged > 45 years old who had routinely undergone DXA to measure their bone mineral density between January 2006 and January 2011. The regions of interest envisaged in our study by using DXA were the lumbar regions L1-L4 and L4-L5. At the same time, they underwent a complete medical examination including personal medical history assessment, biochemical blood analysis, blood pressure measurements and anthropometrical evaluation. Metabolic syndrome was diagnosed attending to the criteria established by National Cholesterol Education Program Adult Treatment Panel III (NECP-ATP-III). This protocol was approved by an Institutional Ethics Committee. Several significant correlations were found between DXA and indices of body fat distribution as well as lipid profile. The strongest correlations were found between fat mass L1-L4 and waist circumference (r= 0.77; p= 0.0016) and levels of HDL-cholesterol (r= -0.58; p= 0.0290). It was concluded that waist circumference and HDL-cholesterol may be recommended to predict fat mass in regions of interest L1-L4 and L3-L4 in postmenopausal women with MS.

Diagnóstico clínico de hiperreactividad bronquial en deportistas de alto rendimiento / Clinical diagnosis of bronchial hyperreactivity in trained athletes

Objetivo: Determinar el diagnóstico de hiperreactividad bronquial inducida por el ejercicio (HIE) en deportistas de un país cálido. Pacientes y métodos: Se realizó un estudio en ochenta deportistas de programas de alto rendimiento. El número de atletas diagnosticados de asma, alergia y/o hiperreactividad bronquial fueron comparadas con las diagnosticadas de forma positiva mediante un test de metacolina. Resultados: Presentaban diagnostico previo un 21,30% de los deportistas estudiados. El presente estudio permitió diagnosticar un 75%, estando por ello no diagnosticados un 53,7%. Conclusión: La HIE ocurre en deportistas incluidos en programas de alto rendimiento y clima cálido más frecuentemente de lo esperado (AU)

The aim of this study is to determine if the clinical history accurately detects exercise-induced hyperresponsiveness (EIH) in sportsmen of high performance. Study design: Study of sportsmen participating in high performance programs. The number of persons positively screened of EIH by clinical history were compared with the number of persons with EIH diagnosed by methacholine test. Results: The screening history identified persons with previous diagnosis suggestive of EIH in 21,30 % of the participants. Among sportsmen with no previous diagnosis of bronchial hyperresponsiveness 53,70% had EIH by methacholine test. Among sportsmen with no previous physical examination of bronchial hyperresponsiveness 70% had EIH by methacholine test. Conclusions: EIH occurs frequently in sportsmen participating in programs of high performance, and hot whether than screening by clinical history accurately detect it (AU)

Obesidad y ejercicio físico / Obesity and physical exercise

El sobrepeso y la obesidad es una enfermedad crónica influenciada por numerosos factores: sociales, conductuales, fisiológicos, metabólicos, celulares y moleculares. El objetivo del presente trabajo es repasar el valor de las diferentes investigaciones en el campo del sobrepeso, la obesidad y el ejercicio físico. La pérdida de peso en personas con sobrepeso es recomendada por sus efectos en la disminución de la presión arterial, los niveles de colesterol, el LDL colesterol y triglicéridos y glucosa, así como la elevación de HDL. El ejercicio físico sin cambios en la dieta produce muy pequeñas pérdidas de peso. La pérdida de peso debe conseguirse con una combinación de dieta, actividad física, terapia de conducta (terapia combinada) pudiendo utilizar otras armas como los fármacos, cirugía, dependiendo de las características del sujeto. El ejercicio físico es una terapia comprensiblemente utilizada pero con unos modestos efectos sobre la pérdida de peso en sujetos con obesidad y sobrepeso. Ayuda a disminuir la grasa abdominal y aumenta la capacidad cardiorrespiratoria y puede ayudar a la pérdida de peso. La actividad física debe combinarse con la dieta baja en calorías. La conclusión principal es que el ejercicio físico se asocia con una mejora en el mantenimiento del peso corporal pero los efectos de un programa de ejercicio son bastante limitados. El mejor método para la pérdida y el mantenimiento del peso se consigue con la terapia combinada y todo bajo control riguroso de la dieta, el ejercicio y los hábitos de vida (AU)