1,721,059 research outputs found
Recovery time profiling after short-, middle- and long-distance swimming performance
No full textWe investigated cardiac autonomic responses and hemodynamic parameters on recovery time following short-, middle- and long-swimming performance. Ten male regional-level swimmers were tested to estimate time and frequency domains of arterial baroreflex sensitivity and heart rate variability after 100-, 200-, and 400-m of front crawl. We found a BRS reduction for 90 min after a maximal 100- and 200-m front crawl event, meanwhile the reflex was restored back to the baseline value about 70 min after 400-m. The vagally mediated HF power of R-R intervals was significantly reduced for 30 min after 400-m, and more than 90 min after 100- and 200-m, with a concomitant increase of sympathetic modulation. After 400-m athletes have reduced their stroke volume for 50 min, which remained at the baseline level following 100- and 200-m. HR was restored back after 90 min in all conditions, whereas TPR was significantly reduced for 50 min after 200- and 400-m, with a persistent reduction after 100-m. Time course of autonomic recovery after 3 different swimming performances is influenced by exercise intensity and duration, showing a rapid recovery after 400-m, an intermediate recovery after 200-m, and a significantly delayed recovery after a more strictly anaerobic performance like 100-m of front crawl. These results could encourage coaches to consider that athlete might be affected by the specific recovery time of the previous exercise performed, suggesting that the management of the exercise intensity, and appropriate monitoring of cardiac autonomic parameters might be helpful to know the physical condition of each athlete
Development and validation of a phase-sensitive bioelectrical equation for estimating skeletal muscle mass using DXA as reference
Full text linkBackground and aim: The development of appropriate bioimpedance-based equations for assessing body composition requires high-standard reference methods. Conversion factors have been proposed to derive skeletal muscle mass (SMM) from dual-energy x-ray absorptiometry (DXA) outputs. The objective of this study was to present a predictive equation for estimating SMM starting from bioelectrical impedance analysis (BIA) and using DXA as criterion. Methods and results: A total of 228 men and 125 women, aged 18–82 years underwent foot-to-hand BIA at a single frequency, alongside DXA scanning. To develop the new equation, bioelectrical parameters were recorded for 2/3 of the total sample and computed in a stepwise regression analysis. Agreement analyses were conducted on the remaining 1/3 of the sample assessing the performance of the new and a previously published equation (Janssen). The best developed model was: SMM (kg) = −17.612 + (sex × 3.397) + (stature2/reactance × 0.037) + (phase angle × 3.509) – (age × 0.052) with a coefficient of determination (R2) of 0.88 and standard error of estimation of 2.25 kg, where sex is 0 for women and 1 for men. Agreement analysis revealed no significant mean bias (−0.01) for the new model, whereas the Janssen equation overestimated SMM (+3.65 kg), with 95 % limits of agreement of −4.2 to 4.2 and −0.1 to 8.0, respectively. Lin's concordance correlation coefficient indicated higher accuracy for the new equations compared to the Janssen equation. Conclusions: This study presents a novel BIA-based predictive equation for assessing SMM in male and female individuals, based on sex, reactance, phase angle, and age
Functional Movement Patterns and Body Composition of High-Level Volleyball, Soccer and Rugby Players
No full textCONTEXT:
Sports practice leads athletes to develop a specific body composition, coordination patterns and basic motor skills based on the different tactical and physical needs.
OBJECTIVES:
This study aimed to present and compare a wide range of functional movement patterns and body composition (BC) parameters of high-level male athletes playing different sports, and to determine if there was a relationship between the parameters examined.
DESIGN:
Cross-sectional study.
SETTING:
Team facilities.
PARTICIPANTS:
Thirty volleyball, twenty-five soccer and thirty rugby players (age 25.9±5.0 years, BMI 25.6±4.1 kg/m2).
INTERVENTIONS:
Functional movement patterns and anthropometric measurements were collected by a physician specifically trained.
MAIN OUTCOME MEASURES:
BMI, fat mass, fat free mass, upper arm muscle and fat area, calf muscle and fat area, thigh muscle and fat area, and functional movement screen (FMS) scores. In addition to considering the FMS total score, we separated the screen into 3 parts: FMSmove, FMSflex and FMSstab.
RESULTS:
The rugby players showed a higher number of asymmetrical and dysfunctional movements than the other athletes (p <0.01), while the highest scores in FMSflex were obtained by the volleyball players (p <0.01). Additionally, most of the asymmetrical and painful movements in the athletes were measured on the shoulder mobility test. Muscle and fat areas differed significantly among the athletes (p <0.05). Significant associations were found between movement patterns and several BC variables. In particular, large negative correlations were measured between percentage of fat mass (r = -0.616; p <0.01), upper arm fat area (r = -0.519; p <0.01) and FMS total score.
CONCLUSIONS:
Functional movement patterns and BC differ in athletes according to the sport practiced. Furthermore, reaching an optimal BC is essential to achieve a satisfactory quality of movement
Changes in Phase Angle and Handgrip Strength Induced by Suspension Training in Older Women
No full textThis study aimed to present a suspension exercise training program suitable for older adults and to verify the effect of 12 weeks of training on handgrip strength (HS) and anthropometric and bioelectrical impedance parameters in older adults. Thirty older women (age 66.1±4.7 years, BMI 30.6±5.3 kg/m2) were randomly assigned to one of two groups: a training group (TG, n=15) or a control group (CG, n=15). The TG participated in a 12-week suspension training program, while the CG maintained their normal physical activity habits for the duration of the study. Anthropometric, bioelectrical impedance and strength parameters were evaluated before and after the intervention period. There was a significant group by time interaction (p<0.05) for triceps, biceps, subscapular skinfold, percentage of fat mass, phase angle (PhA), resistance, reactance, specific resistance, specific reactance and HS, with significant improvements in the TG after the intervention period (p<0.05) even after adjusting for age and BMI. The results suggest that suspension training promotes increases in PhA and HS in older women
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Bioimpedance vector analysis of elite, subelite, and low-level male volleyball players
No full textPurpose: To establish a specific player profile on body-composition parameters and to provide a data set of bioelectric impedances values for male volleyball players. Methods: The study included 201 athletes (age 26.1 [5.4] y, height 191.9 [9.7] cm, weight 86.8 [10.8] kg) registered in the Italian volleyball divisions. The athletes were divided into 3 groups: The elite group comprised 75 players participating in the 1st (Super Lega) division, the subelite group included 65 athletes performing in the 2nd (Serie A2) division, and the low-level group included 61 players participating in the 3rd (Serie B) division. Bioelectric impedance, body weight, and height of the athletes were measured in the second half of the competitive season. In addition, bioelectrical impedance vector analysis was performed. Results: The elite group showed a greater amount of fat-free mass (FFM) and total body water (TBW) and a lower fat mass (FM) than the subelite group (P < .05). In addition, the elite players were taller and heavier and had a higher FFM, FM, TBW, and body cellular mass than the low-level athletes (P < .05). Finally, the mean impedance vectors of the elite group significantly differed from those measured in the normal population and in the other 2 groups (P < .05). Conclusions: This study provides an original data set of body-composition and bioelectric impedance reference values of elite male volleyball players. The results might be useful for interpretation of individual bioimpedance vectors and for defining target regions for volleyball players
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Anthropometry and functional movement patterns in elite Male volleyball players of different competitive levels
Full text linkThe aim of this study was to establish specific profiles for anthropometry and functional movement parameters and identify which characteristics can be modified by training to achieve a better quality of movement in elite male volleyball players competing at the Italian National League (Super Lega = 39, aged 25.6 6 4.7 years and A2 = 30, aged 26.2 6 5.3 years). Another aim was to value functional movement patterns in relation to morphological traits, with special focus on differences by division and playing positions. Statistical significance was set at p # 0.05. According to discriminant analysis, the differences between players of the 2 Divisions were primarily due to nonmodifiable parameters (humerus width, height, and bicrestiliac width) and modifiable parameters (contracted arm circumference and muscle area of upper arm). Our results highlighted differences according to playing positions. Middle hitters and opposites were taller, heavier and generally showed wide dimensions in contracted arm circumference, upper limb length widths, and handgrip strength than the players of the other roles. Percentage of fat mass was low in players of all roles, such as endomorph somatotype component. Ectomor-phic component was maximal in middle hitters, whereas mesomorphic component was maximal in liberos. The players of the 2 Divisions did not show differences in the movement patterns, even if approximately 33% of them showed a dysfunctional movement, with a prevalence of asymmetric movements in the shoulder mobility test. Multiple regression showed that, in volleyball players, an optimal flexibility and mobility was closely related to anthropometric characters with particular emphasis on body fat
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