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The aims of this study were to identify the key external and internal load variables in professional futsal through principal components analysis (PCA), and analyse the physical performance required by the players in official matches. Data were collected from 14 female players during 10 matches using WIMU PROTM. The PCA selected a total of 22 variables as key indicators of players' load. Specifically, these variables were represented by five principal components. However, a novel finding was that different components were extracted when the analysis was carried out by full match (68.83% of total variance), first half (69.81% of total variance), or second half (65.96% of total variance). Also, this study found that the players decreased their physical performance during the second half. Based on these results, this study may help optimize performance and reduce the injury risk. Performance should not be only analysed considering the full match external/internal load but also specifying by match halves. This is explained by the fact that there were variables that made up the principal components in the first half, but not in the second half or full match. Finally, coaches should adopt training strategies which deal with the decrease in physical performance during the second half. [ABSTRACT FROM AUTHOR]

Cycling is a sport where cyclists predominantly adopt a sitting posture, with the trunk tilted forward. This posture requires a high volume of training and duration in several intensities of effort. This study aims to: 1) evaluate the behaviour of the thoracic and lumbar spine flexion and sacral inclination in the sagittal plane, the thoracic and lumbar spine flexion in the frontal plane, and the trunk torsion in the transverse plane; 2) compare the activation of the core muscles as the intensity of effort increases during an incremental test in cycling, and 3) identify which core muscle has a greater activation in each intensity zone. The spinal posture and the activation of the eight core muscles were evaluated in twelve competitive cyclists during incremental cycling intensities. Thoracic and lumbar spine flexion and sacral inclination statistically increased as the intensity of effort increased (Start < VT1 < VT2 < VO2max). A significant increase in muscle activation was observed in all core muscles evaluated as the intensity increased. The rectus abdominis showed statistically significant greater muscle activation than the other core muscles evaluated. In conclusion, as the intensity of effort in cycling increases, cyclists significantly increase the thoracic and lumbar spine flexion, the sacral inclination in the sagittal plane, the thoracic and lumbar spine flexion in the frontal plane, trunk rotation in the transverse plane, as well as the activation of the core muscles. [ABSTRACT FROM AUTHOR]

The aim was to know if cycling affects spinal morphology in postures off the bicycle, such as adapting the spinal curvatures on the bicycle depending on the handlebar type and position on the handlebars. A systematic review was conducted following the PRISMA guidelines. The studies selected met the following criteria: a) the study design was cross-sectional or longitudinal (experimental or cohorts); b) the study evaluated the sagittal morphology of the spine on the bicycle; c) the study included healthy and trained participants without injuries or cyclists reporting low back pain. Fifteen studies reported that a greater pelvic tilt was observed that when the handlebar was in a lower position. Sixteen studies found that lumbar kyphosis was greater when the handlebar grip was lower and farther from the saddle. Twelve studies reported that a tendency towards greater thoracic flexion as the time spent pedalling on the bicycle increased. In conclusion, the practice of cycling produces adaptations in the morphology of the spine of the cyclist compared to non-cyclists, such as an increase in pelvic tilt and a greater capacity for lumbar flexion in trunk flexion positions, and a greater thoracic kyphosis in the standing position. [ABSTRACT FROM AUTHOR]

The aims of this study were to examine the periods in which the maximum speed actions occurred during elite soccer matches and analyse these actions considering the effect of playing position and different contextual variables. Performance-related variables (VMAX: maximum speed; Vo: starting speed; SPD: sprinting distance; ACCMAX: maximum acceleration; DECMAX: maximum deceleration) and sprint-related contextual variables (trajectory, ball possession, role, field area in which the action occurred) from each maximum speed action were collected. The first 15 minutes of each match half elicited most maximum speed actions (44.6% of cases), regardless of playing position (likelihood ratio, LR=13.95; p=0.95). However, playing position had a significant effect on the role of the action (Chi-Squared, χ2=50.68; p=0.001) and the field area in which the sprint occurred (χ2=26.54; p=0.001). Regarding the effect of different contextual variables on the sprint-related performance variables, no significant effect from any contextual variable on ACCMAX, DECMAX or Vo was found (p > 0.05). Nevertheless, the contextual variables had a significant effect on SPD (from ball possession: sprints without ball > sprints with ball; trajectory: non-linear sprints > linear sprints; role: offensive sprints > defensive sprints) and VMAX (from ball possession: sprints without ball > sprints with ball; playing position: midfielders < other positions). [ABSTRACT FROM AUTHOR]

AbstractIn weightlifting exercise, inertial forces result in the force exerted by the athlete being variable throughout the exercise. Many new machines and training methods are intended to maintain a more constant force value. This work aims at developing and evaluating a novel type of bodybuilding machine based on a constant-force mechanism. First, the mechanical design of the proposed constant-force bodybuilding machine (CFBM) is described and its characteristic force curves are obtained by experiments. Then, the performance of an athlete in a lifting exercise carried out in a CFBM is compared to the traditional free weight (FW) exercise in a bench press session. The results demonstrate significantly smaller variations in the force curves for the CFBM than for FW, as well as the disappearance of the braking phase shown by the FW at the end of the concentric phase. Major force differences are identified for a load of 40% of the one repetition maximum (1RM), where the maximum variation in the force curve for the FW is two times higher than for FW. Differences in velocity and power curves are also reported and analized. For the 80% of 1RM the peak and mean powers are found to be 27% and 34% higher, respectively, for CFBM than for FW. [ABSTRACT FROM AUTHOR]

The aims of this study were to 1) determine the key load indicators in professional soccer through principal component analysis (PCA); and 2) analyse the load variability of each training and match day within the microcycle considering the principal components. Data from 111 load variables were collected using tracking systems in both training and match days (MD). The results showed that 7 variables, which belonged to the first two components of the PCA, explained 80.3% of total variance. Specifically, these variables were Metabolic power, total of steps, Fourier transform (FFT) duration, deceleration distance covered (2–3 m/s2), total of running actions (12–18 km/h; 21–24 km/h), and distance covered (6–12 km/h). Regarding the analysis of the load variability of each training and match day within the microcycle, the lowest load variability was observed in −1MD. Also, a great load variability in +1MD with significant differences compared to −5MD (p<0.001; d=0.49) and −4MD (p=0.01; d=0.26) was found. This study suggests the use of the PCA in the context of team sports to reduce the large number of variables, which are daily managed by strength and conditioning coaches, in addition to the analysis of load variability of each training and match day within the microcycle. [ABSTRACT FROM AUTHOR]

This study analysed the periods in which the most demanding passages (MDP) of play occurred during professional soccer matches, considering different criterion variables and investigating the effect that the playing position had on the MDP-of-play occurrence for each criterion variable. The MDP of play were calculated based on five criterion variables: distance covered (DIS), sprinting distance (SPD), high-metabolic load distance (HMLD), and the total of high-intensity accelerations and decelerations (ACCHIGH and DECHIGH). The results showed that the first period of the match (0ʹ-15ʹ) was the interval with the highest frequency (i.e., the greatest % of cases) in which the players achieved the MDP of play for all the variables (DIS= 38.9%; SPD= 28.4%; HMLD= 37.7%; ACCHIGH= 54.3%; DECHIGH= 48.8%). The playing position had no significant effect on MDP-of-play occurrence in any variable (likelihood ratio, LR= 15.88–32.05; p > 0.05; effect size, ES= 0.01–0.04), except for the DIS covered (LR= 32.05; p= 0.04; ES= 0.05), in which the most frequent MDP for the full backs occurred within the second period of the match (15ʹ-30ʹ). In conclusion, the first periods of the matches usually elicited the MDP of play and these periods need to be trained to prevent injuries and optimize performance. [ABSTRACT FROM AUTHOR]

The aims of this research were to analyse the effect that different playing positions, passage durations and starting status had on the most demanding passages (MDP) of play in professional football matches. Players were categorized by positions and the MDP of distance (DIS), high-speed running distance (HSRD) and sprinting distance (SPD) were analysed for four passage durations (1, 3, 5 and 10 minutes). The results indicated that DIS (p < 0.001), HSRD (p < 0.001) and SPD (p < 0.001) covered per minute decreased as the passage durations increased for all positions. Regarding the playing position, it had a significant effect on the DIS (p < 0.001), HSRD (p < 0.001) and SPD (p < 0.001) covered. In addition, although the results reported that the starting status had no significant effect on the DIS (p = 0.36) covered, it had a statistically significant effect on the HSRD (p = 0.01) and SPD (p < 0.001) covered. Coaching and medical departments should consider the impact that these variables have on players' performance when designing training drills aimed at preparing the player for the competitive demands. [ABSTRACT FROM AUTHOR]

The aim of this quasi-experimental pilot study was to explore the effects of a reformer Pilates program on the anthropometry, body composition, and somatotype of active adult women after a short non-exercise period. Twenty-eight women (mean age: 40.21 ± standard deviation of 8.12 years old) with one to three years of reformer Pilates experience participated in the study. The women participated in a reformer Pilates program for 16 weeks (one hour, twice per week) after 4 weeks of detraining (summer holidays) in 2012. The International Society for the Advancement of Kinanthropometry full profile was assessed before and after the intervention program. Significant decreases (p ≤ 0.05) from pre- to post-program were observed for triceps, iliac crest, supraspinale, abdominal, front thigh and medial calf skinfold thicknesses, six and eight skinfold thickness sums, forearm and ankle girths, waist/hip ratio, endomorphy, and fat mass. Significant increases (p ≤ .05) were observed for corrected arm, corrected calf girths, and muscle mass. Generally, women showed a mesomorphic endomorph (endomorphy predominant) and mesomorph–endomorph (endomorphy and mesomorphy predominant) in the pre- and posttests, respectively. In conclusion, the practice of reformer Pilates was associated with healthy changes in anthropometric parameters, body composition, and somatotype in Pilates-experienced women after 4 weeks of no physical exercise. [ABSTRACT FROM PUBLISHER]