Physical activity quantification in elder women

Cuantificación de la actividad física en mujeres mayores

Myosin Light Chain Kinase (MLCK) Gene Influences Exercise Induced Muscle Damage during a Competitive Marathon

Myosin light chain kinase (MLCK) phosphorylates the regulatory light chain (RLC) of myosin producing increases in force development during skeletal muscle contraction. It has been suggested that MLCK gene polymorphisms might alter RLC phosphorylation thereby decreasing the ability to produce force and to resist strain during voluntary muscle contractions. Thus, the genetic variations in the MLCK gene might predispose some individuals to higher values of muscle damage during exercise, especially during endurance competitions. The aim of this investigation was to determine the influence of MLCK genetic variants on exercise-induced muscle damage produced during a marathon. Sixty-seven experienced runners competed in a marathon race. The MLCK genotype (C37885A) of these marathoners was determined. Before and after the race, a sample of venous blood was obtained to assess changes in serum myoglobin concentrations and leg muscle power changes were measured during a countermovement jump. Self-reported leg muscle pain and fatigue were determined by questionnaires. A total of 59 marathoners (88.1%) were CC homozygotes and 8 marathoners (11.9%) were CA heterozygotes. The two groups of participants completed the race with a similar time (228 ± 33 vs 234 ± 39 min; P = 0.30) and similar self-reported values for fatigue (15 ± 2 vs 16 ± 2 A.U.; P = 0.21) and lower-limb muscle pain (6.2 ± 1.7 vs 6.6 ± 1.8 cm; P = 0.29). However, CC marathoners presented higher serum myoglobin concentrations (739 ± 792 vs 348 ± 144 μg·mL-1; P = 0.03) and greater pre-to-post- race leg muscle power reduction (-32.7 ± 15.7 vs -21.2 ± 21.6%; P = 0.05) than CA marathoners. CA heterozygotes for MLCK C37885A might present higher exercise-induced muscle damage after a marathon competition than CC counterparts

Interindividual variability in sweat electrolyte concentration in marathoners

Background: Sodium (Na+) intake during exercise aims to replace the Na+ lost by sweat to avoid electrolyteimbalances, especially in endurance disciplines. However, Na+ needs can be very different among individuals because of the great inter-individual variability in sweat electrolyte concentration. The aim of this investigation was to determine sweat electrolyte concentration in a large group of marathoners. Methods: A total of 157 experienced runners (141 men and 16 women) completed a marathon race (24.4 ± 3.6 °C and 27.7 ± 4.8 % of humidity). During the race, sweat samples were collected by using sweat patches placed on the runners’ forearms. Sweat electrolyte concentration was measured by using photoelectric flame photometry. Results: As a group, sweat Na+ concentration was 42.9 ± 18.7 mmol·L−1 (minimal-maximal value = 7.0–95.5 mmol·L−1), sweat Cl− concentration was 32.2 ± 15.6 mmol·L−1 (7.3–90.6 mmol·L−1) and sweat K+ concentration was 6.0 ± 0.9 mmol·L−1 (3.1–8.0 mmol·L−1). Women presented lower sweat Na+ (33.9 ± 12.1 vs 44.0 ± 19.1 mmol·L−1; P = 0.04) andsweat Cl− concentrations (22.9 ± 10.5 vs 33.2 ± 15.8 mmol·L−1; P = 0.01) than men. A 20 % of individuals presented asweat Na+ concentration higher than 60 mmol·L−1 while this threshold was not surpassed by any female marathoner. Sweat electrolyte concentration did not correlate to sweat rate, age, body characteristics, experience or training. Although there was a significant correlation between sweat Na+ concentration and running pace (r = 0.18; P = 0.03), this association was weak to interpret that sweat Na+ concentration increased with running pace. Conclusions: The inter-individual variability in sweat electrolyte concentration was not explained by any individual characteristics except for individual running pace and sex. An important portion (20 %) of marathoners might need special sodium intake recommendations due to their high sweat salt losses

The Role of Stress in Understanding Differences in Sedentary Behavior in Hispanic/Latino Adults: Results from the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study

Chronic stress and/or lifetime traumatic stress can create a self-reinforcing cycle of unhealthy behaviors, such as overeating and sedentary behavior, that can lead to further increases in stress. This study examined the relationship between stress and sedentary behavior in a sample of Hispanic/Latino adults (N = 4244) from the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study

Elevation of Cardiac Troponins After Endurance Running Competitions

In the present investigation, we selected 63 healthy runners (in triplets) from a group of 322 nonprofessional finishers because of their similarities in age (mean±SD age, 37±7 years), anthropometry (66.9±12.8 kg), and running experience (3.3±0.2 years). The triplets also had similar 10-year absolute cardiovascular risks (2.8±2.1%) calculated by the non–laboratory-based Framingham function.5 In each group, there were 13 women and 8 men. From each triplet, 1 runner competed in a 10-km race, another in a half-marathon race, and the third in a full marathon race. As would be expected, as a result of the different training patterns for each distance, training volume in the month before the race increased with the competition distance (23.9±9.0, 34.8±8.0, and 40.6±16.4 km/wk for 10-km runners, half-marathoners, and marathoners, respectively; P<0.01). Before and 10 minutes after the race, body mass was measured to assess dehydration. Blood samples were obtained to measure cardiac biomarkers, including high-sensitivity cardiac troponins I and T, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and the cardiac (creatine kinase-MB) and skeletal muscle (creatine kinase-MM) isoenzymes of creatine kinase and myoglobin at the end of the races. The between-group differences in these variables were analyzed by a 2-way ANOVA. The study was approved by the Ethics Committee for Research of the Camilo Jose Cela University. All the research protocols described here were carried out in accordance with the Declaration of Helsinki, and all subjects gave informed consent to participate in the study

Plan de comercialización para el dulce de papaya empresa Conservas Risaralda, año 2015

CD-T 658.83 A75;123 p.El estudio que aquí se motiva tiene el interés de identificar la mejor manera de comercializar un producto de alimentos de manera adecuada, velando por la presencia eficiente del mismo en los canales determinados, a un precio adecuado, con sentido de responsabilidad social y generándole valor a la empresa que lo produce.Universidad Libre Seccional Pereir

The use of energy drinks in sport: perceived ergogenicity and side effects in male and female athletes

The use of caffeine containing energy drinks has dramatically increased in the last few years, especially in the sport context because of its reported ergogenic effect. The ingestion of low to moderate doses of caffeinated energy drinks has been associated with adverse side effects such as insomnia or increased nervousness. The aim of the present study was to assess psycho-physiological changes and the prevalence of side effects resulting from the ingestion of 3 mg caffeine/kg body mass in the form of an energy drink. In a double-blind and placebo controlled experimental design, ninety experienced and low-caffeine-consuming athletes (fifty-three male and thirty-seven female) in two different sessions were provided with an energy drink that contained 3 mg/kg of caffeine or the same decaffeinated energy drink (placebo; 0 mg/kg). At 60 min after the ingestion of the energy drink, participants completed a training session. The effects of ingestion of these beverages on psycho-physiological variables during exercise and the rate of adverse side effects were measured using questionnaires. The caffeinated energy drink increased self-perceived muscle power during exercise compared with the placebo beverage (6·41 (sd 1·7) v. 5·66 (sd 1·51); P= 0·001). Moreover, the energy drink produced a higher prevalence of side effects such as insomnia (31·2 v. 10·4 %; P0·05). The ingestion of an energy drink with 3 mg/kg of caffeine increased the prevalence of side effects. The presence of these side effects was similar between male and female participants

Efectos de una maratón en valores hematológicos

Introducción: La maratón lleva asociado un estrés fi siológico en el organismo, si bien existe carencia de información sobre cómo afecta a los parámetros sanguíneos en corredores populares y si existe relación con variables de rendimiento, entrenamiento y experiencia deportiva. Propósito: Evaluar los cambios producidos en variables hematológicas en corredores populares tras participar en una maratón en ambiente caluroso. Un segundo objetivo fue analizar la relación entre la experiencia deportiva, el nivel de entrenamiento y el tiempo de carrera con los cambios hematológicos. Métodos: Se extrajo sangre venosa a 41 maratonianos, 35 hombres y 6 mujeres, antes y después de una maratón. Su edad fue de 41,15+8,1 años, y entrenaban como media 55,917,12 kilómetros semanales. El tiempo en meta fue de 3:40:410:32:02. Las muestras fueron medidas con analizadores bioquímicos estándar para determinar los valores de la serie roja y serie blanca

Acute consumption of a caffeinated energy drink enhances aspects of performance in sprint swimmers

This study investigated the effect of a caffeinated energy drink on various aspects of performance in sprint swimmers. In a randomised and counterbalanced order, fourteen male sprint swimmers performed two acute experimental trials after the ingestion of a caffeinated energy drink (3 mg/kg) or after the ingestion of the same energy drink without caffeine (0 mg/kg; placebo). After 60 min of ingestion of the beverages, the swimmers performed a countermovement jump, a maximal handgrip test, a 50 m simulated competition and a 45 s swim at maximal intensity in a swim ergometer. A blood sample was withdrawn 1 min after the completion of the ergometer test. In comparison with the placebo drink, the intake of the caffeinated energy drink increased the height in the countermovement jump (49·4 (SD 5·3) v. 50·9 (SD 5·2) cm, respectively; P<0·05) and maximal force during the handgrip test with the right hand (481 (SD 49) v. 498 (SD 43) N; P<0·05). Furthermore, the caffeinated energy drink reduced the time needed to complete the 50 m simulated swimming competition (27·8 (SD 3·4) v. 27·5 (SD 3·2) s; P0·05). A caffeinated energy drink increased some aspects of swimming performance in competitive sprinters, whereas the side effects derived from the intake of this beverage were marginal at this dosag