Sedentary lifestyle of university students is detrimental to the thoracic spine in men and to the lumbar spine in women.

BACKGROUND: Sitting for long periods of time and lack of physical activity in young adults can cause postural deterioration leading to rapid onset of fatigue and increase the risk of back pain. We were interested in whether there are gender differences in spinal curvature among university students with a predominantly sedentary lifestyle. METHODS: 20 sedentary female (age 20 ± 0.73 years) and 39 sedentary male university students (age 20 ± 1.08 years) participated in this study. Their thoracic and lumbar curvatures were assessed while standing and sitting using a Spinal Mouse. RESULTS: In standing, 80.0% of the females and 69.2% of the males had a neutral position of the thoracic spine (33.25° and 35.33°, respectively). However, more males, 30.8%, than females, 10.0%, had hyperkyphosis (54.27° and 47.0°, respectively). Hypokyphosis was found in 10.0% of the females (18.50°) and none in the males. Similarly, 90.0% of the females and 97.4% of the males had neutral position of the lumbar spine (-33.11° and -29.76°, respectively). Increased hyperlordosis was found in 10.0% of the females and 2.6% of the males (-41.0° and -50.0°, respectively). Hypolordosis was not detected in either females or males. In sitting, on the other hand, 70.0% of the females and only 33.3% of the males had a neutral position of the thoracic spine (30.20° and 30.62°, respectively). Increased hyperkyphosis was found in 46.2% of the males (59.76°) and none of the females. 30.0% of the females and 23.1% of the males had light hypokyphosis (47.50° and 46.67°, respectively). Similarly, 70.0% of the females and only 38.5% of the males had a neutral position of the lumbar spine (7.0° and 6.6°, respectively). 35.9% of the males and only 5.0% of the females had a light hypokyphosis (16.14° and 16.0°, respectively). Slightly increased hyperkyphosis was identified in 25.6% of the males and 25.0% of the females (23.9° and 22.5°, respectively). CONCLUSION: There are significant gender differences in spinal curvature. While in the thoracic spine it was to the detriment of the males when both standing and sitting, in the lumbar spine it is related to the females only when standing. It is therefore necessary to eliminate these spinal deviations in young adults induced by prolonged sitting during university courses by appropriate recovery modalities.

Using Microtechnology and the Fourier Transform for the Analysis of Effective Activity Time in Professional Soccer.

ABSTRACT: Oliva-Lozano, JM, Chmura, P, Granero-Gil, P, and Muyor, JM. Using microtechnology and the Fourier Transform for the analysis of effective activity time in professional soccer. J Strength Cond Res 37(12): 2491-2495, 2023-This study aimed to investigate the use of the fast Fourier transform (FFT) for the analysis of effective activity time in professional soccer by (a) exploring the relationship between this variable and standard external load parameters and (b) analyzing the effective activity time during official professional soccer matches. Twenty-six male players participated in the study. Each player was categorized as midfielder, central defender, full-back, wide-midfielder, or forward. Tracking systems based on inertial sensors (4 3D accelerometers, 3 3D gyroscopes, and 1 magnetometer), and global positioning systems technology were used to collect external load measures for 35 matches. Each match was analyzed considering 15-minute periods to explore the evolution of effective activity time during the matches. The extra time from each match was also included. Fast Fourier transform duration may be a representative variable of effective activity time, given the strong positive correlation with the external load variables ( p < 0.001). The linear regression analysis showed that the variables that significantly contributed to the model ( R2 = 0.97) were the total of steps and the distance covered. The mean effective activity time in soccer match play was ∼48.69 minutes. This time significantly changed depending on factors such as the period of the match ( F = 239.05; p < 0.001; ηp 2 = 0.60) or playing position ( F = 16.99; p < 0.001; ηp 2 = 0.06). The greatest effective activity time was observed for all playing positions in the 0'-15' period. However, the 60'-75' period showed the lowest effective activity times compared with the rest of the 15-minute periods for all positions except for forwards (75'-90'). From a practical standpoint, sports performance practitioners may consider these results to improve the individualization of training and match demands. Also, a more accurate indicator of exercise intensity may be obtained (e.g., multiplying the rating of perceived exertion by the effective activity time).

Comparison of Muscle Activity between the Horizontal Bench Press and the Seated Chest Press Exercises Using Several Grips.

This study aims to compare muscle activity in the pectoralis major, anterior deltoid, and triceps brachii in the horizontal bench press exercise with a prone grip at 150% and 50% of the biacromial width and the seated chest press exercise with two types of grips (a neutral grip at ~150% of the biacromial width and a prone grip at ~200% of the biacromial width). Twenty physically active adults performed a set of 8 repetitions at 60% of the one repetition maximum. The results showed that the clavicular portion of the pectoralis major had significantly greater muscle activity in the seated chest press exercise with a neutral grip (~30% of the maximal voluntary isometric contraction (MVIC)) than in the lying bench press exercise with a prone grip at 150% of the biacromial width (~25% MVIC). The muscle activity of the anterior deltoid was not significantly different across any exercise or grip evaluated (~24% MVIC). The muscle activity of the triceps brachii was significantly higher in the lying bench press exercise with a grip at 50% biacromial width (~16% MVIC) than at 150% of the biacromial width (~12% MVIC). In conclusion, all exercises and grips showed similar muscle activity, and the selection of these exercises should not be based exclusively on the grounds of muscle activation but rather on the load capacity lifted, the level of technique of the participant, and/or the transference to the specific sporting discipline or event.

When and How Do Soccer Players From a Semi-Professional Club Sprint in Match Play?

The aims of this study were to investigate the periods in which sprints occurred during official matches and analyze these sprints considering the effect of the playing position and different contextual variables. Electronic performance and tracking systems were used for the analysis of all sprints performed by players. Matches were recorded by video and synchronized with performance tracking data. A total of 252 sprints were analyzed. The greatest frequency of sprints was observed in the period 1 (0'-15'), followed by period 2 (15'-30') and period 6 (75'-90'), regardless of the playing position (χ2 = 31.35; p = 0.051). Most sprints were non-linear (non-linear sprints: 97.6%; linear sprints: 2.4%) and without ball possession (without ball possession: 95.2%; with ball possession: 4.8%) for all playing positions, but the role of the sprint and the field area in which the sprint occurred were dependent on the position (p < 0.001). Specifically, players covered ~17.55 m per sprint, starting at ~10.34 km/h, reaching ~26.74 km/h, maximally accelerating at ~2.73 m/s2, and decelerating at ~3.61 m/s2. Overall, the playing position and contextual variables had no significant effect on physical performance variables analyzed during these sprints. Therefore, this study allows performance practitioners to have a better understanding of when and how soccer players sprint in match-play. In this regard, this study presents some training and testing strategies that may be considered to improve performance and decrease injury risk.

Monitoring physical match performance relative to peak locomotor demands: implications for training professional soccer players.

This study aimed to analyse physical performance relative to peak locomotor demands of match play. Data were collected during 13 professional soccer matches. Initially, the 1-minute peak values were registered in each match, including the percentage of the total distance (TD), high-speed running distance (HSRD), sprinting distance (SPD), and high-metabolic load distance (HMLD), and a total of high-intensity accelerations and decelerations (Acc+Dec). Secondly, the time (measured in minutes) spent at different percentage ranges for the 1-minute peak values registered in each match was calculated. Thirdly, the physical performance required in the different percentage ranges for the 1-minute peak values were obtained. Finally, the time and physical performance required above the 90-minute average demands were calculated. The 90-minute average for all playing positions represented ~53% of the total distance (TD), ~23.4% of high-metabolic load distance (HMLD), ~16% of high-speed running distance (HSRD), ~11% of the total of high-intensity accelerations and decelerations (Acc+Dec), and ~6% of sprinting distance (SPD) for the 1-minute peak values. Likewise, statistically significant differences (p < 0.05) in the physical performance and time spent between specific percentage ranges for the 1-minute peak locomotor demands were also noted. In addition, all the variables reported that the physical performance required for above 90-minute average demands were significantly greater (p < 0.05) than the 90-minute average demands. Therefore, these findings may guide the prescription of training intensity by considering the physical performance relative to the peak locomotor demands of match play.

Is there any relationship between match running, technical-tactical performance, and team success in professional soccer? A longitudinal study in the first and second divisions of LaLiga.

The aim of this study was to analyze the association between teams' success at the end of the season and match running, and technical-tactical performance in two professional soccer leagues. Match running, and technical-tactical performance data were collected during two consecutive seasons. A Factor Analysis was conducted to reduce the number of performance variables into a fewer number of factors. The scree plot with parallel analysis revealed that five factors should be retained. Then, a multiple linear regression analysis was performed to explain which variables and factors were more associated with teams' success at the end of the season. The main findings of this study were that factor 3, which was correlated with goals scored, possessions ending with a goal, shots on target, goals from set plays, goals from a direct free kick, offsides, and goals conceded, was the most important contributor to teams' success (ß = 0.66). In addition, this study observed a significant interaction (p = 0.001) between the second division of LaLiga and factor 2, which correlated with total distance (TD), sprinting distance (SPD), and sprinting actions (SPA) when opponent team owns the ball, tackles, shots inside the box, and fouls received. This implies that factor 2 had a different effect on the total points at the end of the season depending on the league. However, factor 2 had no effect on the first division. In conclusion, technical-tactical performance variables were usually more closely linked to the team's success in both leagues than match running performance data. Regarding the technical-tactical performance, teams may focus on drills that promote goal situations, shooting accuracy, the total of shots performed in match play, and set pieces. However, defensive skills need to be reinforced considering the importance of goals conceded for team success in both divisions. When it comes to the match running performance, teams are encouraged to focus on offensive actions, in which they possess and run with the ball (especially at high speed) and defensive actions in which the players perform continuous and high-intensity physical efforts to prevent the opponents from scoring, avoid counterattacks, stay compact, and defend the area and goal.

The impact of urinary incontinence on multiple health outcomes: an umbrella review of meta-analysis of observational studies.

BACKGROUND AND AIM: We aimed to capture the breadth of health outcomes that have been associated with the presence of Urinary Incontinence (UI) and systematically assess the quality, strength, and credibility of these associations through an umbrella review and integrated meta-analyses. METHODS: We assessed meta-analyses of observational studies based on random-effect summary effect sizes and their p-values, 95% prediction intervals, heterogeneity, small-study effects, and excess significance. We graded the evidence from convincing (Class I) to weak (Class IV). RESULTS AND DISCUSSION: From 3172 articles returned in search of the literature, 9 systematic reviews were included with a total of 41 outcomes. Overall, 37 out of the 41 outcomes reported nominally significant summary results (p < 0.05), with 22 associations surviving the application of a more stringent p-value (p < 10-6). UI was associated with worse scores than controls in female sexual function (Class II), while it was also associated with a higher prevalence of depression (odds ratio [OR] = 1.815; 95% confidence interval [CI]: 1.551-2.124), and anxiety (OR = 1.498; 95% CI: 1.273-1.762) (Class IV). UI was associated with poorer quality of life (QoL), higher rate of mortality (hazard ratio = 2.392; 95% CI: 2.053-2.787) an increase in falls, frailty, pressure ulcers, diabetes, arthritis, and fecal incontinence (Class IV). CONCLUSIONS: UI is associated with female sexual dysfunction, with highly suggestive evidence. However, the evidence of other adverse outcomes including depression, anxiety, poorer QoL, higher mortality, falls, pressure ulcers, diabetes, arthritis, fecal incontinence, and frailty is only weak. A multidimensional approach should be taken in managing UI in the clinical setting.

When and how do professional soccer players experience maximal intensity sprints in LaLiga?

OBJECTIVES: To 1) examine the periods in which maximal intensity sprints occurred during professional soccer matches and 2) analyze the maximal intensity sprints registered in match play considering the effect of playing position and other contextual variables. METHODS: A total of 1252 match observations were collected from 277 male professional players. Sprinting actions at maximal intensity were analyzed during 30 matches, and both contextual and performance variables were collected using performance tracking systems. RESULTS: Maximal intensity sprints were more frequent in the first and last periods of the match (0'-15'; 75'-90'), regardless of the playing position (χ2=23.01; p=0.29; ES=0.07). These sprints were usually non-linear actions without possession of the ball and had different tactical purposes depending on the position. The mean sprint duration ranged from ~4.9 s to ~9 s, the mean distance covered ranged from ~30 m to ~55 m, while the mean maximum velocity was between ~30.12 and ~32.80 km/h depending on the tactical purpose and playing position. CONCLUSION: Professional soccer players need to be prepared during warm-ups for maximal intensity sprints in the first period of the match as well as maximal intensity sprints under high fatigue conditions given the frequency of sprints in the last period of the match. Also, training drills should be designed with a special focus on non-linear sprints without possession of the ball, based on the main tactical purpose of each position (e.g., CD: interceptions; MF: recovery runs; FB, WMF and FW: run the channel).

Effect of incremental intensities on the spinal morphology and core muscle activation in competitive cyclists.

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.

Key load indicators and load variability in professional soccer players: a full season study.

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.

Analysis of key external and internal load variables in professional female futsal players: a longitudinal study.

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.

When and how do elite soccer players sprint in match play? A longitudinal study in a professional soccer league.

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).

When do soccer players experience the most demanding passages of match play? A longitudinal study in a professional team.

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 (0'-15') 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 (15'-30'). 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.

Exploring the Use of Player Load in Elite Soccer Players.

BACKGROUND: The aims of this study were to (1) analyze the distribution of the player load (PLTOTAL) in 3 axes of movement (PLAP, anterior-posterior; PLML, medial-lateral; PLV, vertical) during elite soccer matches, (2) investigate the effect of playing position on PL-related variables, and (3) explore the association between PLTOTAL and distance covered by the players. HYPOTHESIS: Despite different load distribution between axes of movement, PLTOTAL might be used as a body load indicator for all playing positions. STUDY DESIGN: Longitudinal study. LEVEL OF EVIDENCE: Level 3. METHODS: Data were collected from elite soccer players using WIMU Pro tracking systems, which included inertial sensors. RESULTS: The axis of movement had a significant effect on the distribution of the load (P < 0.001; conditional R2 = 0.91), with the greatest contribution from the PLV (P < 0.001; d = 5.41-5.86). Moreover, no effect of playing position on PLTOTAL, PLV, PLML, or PLAP was observed (P > 0.05). Finally, a large correlation was found between PLTOTAL and distance covered, and the linear mixed model showed that distance may be predicted by the PLTOTAL (conditional R2 = 0.81; P < 0.001). CONCLUSION: Differences in load distribution were based on the axis of movement, although playing position had no effect on any variable. The selection of either distance covered, which is representative of a 2-dimensional analysis, or PLTOTAL, which is representative of a 3-dimensional analysis, may be adequate for monitoring locomotor demands or accelerometer-derived load. CLINICAL RELEVANCE: Training strategies that focus on the vertical component of match play should be adopted. In addition, given that PLTOTAL is an accelerometry-based metric, which combines the accelerations in anterior-posterior, medial-lateral, and vertical planes, strength and conditioning coaches may use this parameter as a measure of total body load.

Effect of the Length of the Microcycle on the Daily External Load, Fatigue, Sleep Quality, Stress, and Muscle Soreness of Professional Soccer Players: A Full-Season Study.

BACKGROUND: The aim of this study was to analyze the effect of the length of the microcycle (ie, training period from the day after the match to the following match) on the daily external load and perceived wellness of professional soccer players (Spanish LaLiga Smartbank). HYPOTHESIS: The length of the microcycle has a significant effect on the daily external load and perceived wellness. STUDY DESIGN: Longitudinal study. LEVEL OF EVIDENCE: Level 3. METHODS: Data were collected daily during a full season using perceived wellness questionnaires and electronic performance and tracking systems. RESULTS: The length of the microcycle had a significant effect on volume- and intensity-related external load variables. There were differences between short, regular, and long microcycles depending on the day of the microcycle. These differences were observed in all external load variables. However, no significant differences between short, regular, or long microcycles were found on match day for any external load variable, except for high-intensity decelerations. Regarding the perceived wellness, the length of the microcycle had no effect on these variables, and there were no significant interactions between the length and the day of the microcycle. CONCLUSION: The length of the microcycle had a significant effect on volume- and intensity-related external load variables, but no significant effect on perceived wellness was observed. CLINICAL RELEVANCE: These data may help strength and conditioning coaches understand that workload periodization should take this contextual variable into account, especially for external training load. In addition, this study may serve as a guide for practitioners to know the physical requirements of professional soccer players in Spanish LaLiga Smartbank, because the weekly external load profile and perceived wellness have been reported for different lengths of the microcycles. Thus, these data may be used for player load management.

Effects of cycling on the morphology and spinal posture in professional and recreational cyclists: a systematic review.

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.

Evaluation of Dynamic Spinal Morphology and Core Muscle Activation in Cyclists-A Comparison between Standing Posture and on the Bicycle.

(1) Background: Cycling is characterized by a sustained sitting posture on the bicycle, where physiologic spinal curvatures are modified from standing to cycling. Therefore, the main objective was to evaluate and compare the morphology of the spine and the core muscle activity in standing posture and cycling at low intensity. (2) Methods: Twelve competitive cyclists participated in the study. Spinal morphology was evaluated using an infrared-camera system. Muscle activation was recorded using a surface electromyography device. (3) Conclusions: The lumbar spine changes its morphology from lordosis in standing to kyphosis (lumbar flexion) when pedaling on the bicycle. The sacral tilt significantly increases its anterior tilt when cycling compared to when standing. The spinal morphology and sacral tilt are dynamic depending on the pedal's position during the pedal stroke quadrants. The infraspinatus, latissimus dorsi, external oblique, and pectoralis major showed significantly higher activation pedaling than when standing, although with very low values.

Using Inertial and Physiological Sensors to Investigate the Effects of a High-Intensity Interval Training and Plyometric Program on the Performance of Young Judokas.

The use of inertial and physiological sensors in a sport such as judo is scarce to date. The information provided by these sensors would allow practitioners to have a better understanding of sports performance, which is necessary for an accurate training prescription. The purpose of this study was to use inertial and physiological sensors in order to investigate the effect of a plyometric and high-intensity interval training (HIIT) training program on Special Judo Fitness Test (SJFT) performance and speed of execution of throws in young judokas. A total of 32 participants were divided into two groups: experimental and control. The intervention consisted of six sessions with a duration of 60 min for 3 weeks. Physiological sensors collected heart rate data to assess the Special Judo Fitness Test, and inertial sensors collected angular velocity. The results show a significant decrease in the SJFT index (Score pre: 22.27 ± 2.73; Score post: 19.65 ± 1.70; p ≤ 0.05; d = 0.61) and a significant increase in the angular velocity of the X-axis (Pre: 320.87 ± 51.15°/s; Post: 356.50 ± 40.47°/s; p ≤ 0.05; d = 0.45) and Y-axis (Pre: 259.40 ± 41.99°/s; Post: 288.02 ± 65.12°/s; p ≤ 0.05; d = 0.31) in the experimental group. In conclusion, this study demonstrates that using inertial and physiological sensors allowed us to analyze the effect that a high-intensity interval training program and plyometrics had on the performance of young judokas. Strength and conditioning coaches should consider these results because including plyometric training and HIIT in judokas' workout programming can be especially positive for eliciting increases in performance. However, future training interventions should investigate the training adaptations to longer interventions.

Physical Performance Indicators and Team Success in the German Soccer League.

The aims of this study were (1) to determine the match running performance required by different teams based on their final ranking position and (2) to analyze the association between match running performance variables and team success at the end of the season. A total of 1,224 match observations from professional soccer teams competing during two consecutive seasons in the German Bundesliga were analyzed. In addition, the final league ranking position and the total of points obtained by each team at the end of the season were registered for the analysis of the association between team success and match running performance. The main findings were that high ranked teams covered the greatest total distance with ball possession, sprinting distance with ball possession, and completed the greatest number of sprinting actions with ball possession and maximal velocity. Moreover, total distance covered with possession of the ball and maximal velocity were the most important variables to predict the total of points obtained at the end of the season. Specifically, the relative contribution of total distance covered with ball possession to the total of points obtained was greater than maximal velocity. Training programs for professional soccer players should be focused on improving the sprint capacity and running with possession of the ball (e.g., transitional tasks and small-sided games). Moreover, this has implications for injury prevention, physical, psychological, and technical-tactical training since today's soccer requires players to engage in repeated high-intensity actions, reach maximum speeds above 9 m/s, and develop technical-tactical coordination when running with the ball.

Understanding the FIFA quality performance reports for electronic performance and tracking systems: from science to practice.

The world's football-governing body, FIFA, developed the FIFA Quality Programme to set internationally recognized industry standards for electronic performance and tracking systems (EPTS). The positioning and velocity data from different EPTS, discretized into velocity bands, were validated against criteria measures. Discussions have been ongoing between practitioners regarding the FIFA quality performance reports, particularly when the findings are used to compare accuracy between systems. However, there are important methodological issues that should be addressed when interpreting these findings. The aim of this article is to provide practitioners with guidance on interpreting the results of FIFA's EPTS quality performance reports. We demonstrate that several methodological factors should be considered. For example, EPTS reports evaluate individual systems against criteria measures but systems are often not evaluated concurrently (e.g., on the same day using the same participants). Furthermore, technical considerations such as the total number of cameras used for optical (OPT) systems, the total number of antennas used by local positioning systems (LPS), the total number of satellites available for global navigation satellite systems (GNSS) and the velocity bands should be considered before interpreting the post-test results reported for each EPTS. Specifically, comparisons between GNSS, LPS and/or OPT systems are inadvisable unless they are used within the same observation.