Testing variations between starters and substitute players in terms of total distance, high-speed running, and sprinting distance: a descriptive study on professional male soccer players.

The purpose of this study was three-fold: (i) to compare total distance, high-speed running (HSR) distance, and sprint distance covered per 5-minute epoch by players acting as both starters and substitutes; (ii) to compare the locomotor demands between the moments the players entered the match (45-60, 60-75 and 75-90 minutes); and (iii) to compare the locomotor demands of the players between the variations of the within- and between-playing positions. Twenty-one male professional soccer players competing in the Professional Premier League of one of the European countries were observed over sixteen official matches. The players were monitored during all matches using a Global Navigation Satellite System. The measures collected were total distance (TD; m), distance in HSR, sprint distance, HSR, and sprint counts. Considering the comparisons between the splits over the second half of match play, a significant difference between the starters and the substitutes was observed only for sprint distance in the 90-95 minute split (Z = -2.023; p = 0.043). Moreover, no substantial differences were found between the moment the substitute player entered the match regarding total distance (H = 2.650; p = 0.266), HSR distance (H = 1.738; p = 0.419), and sprint distance (H = 0.048; p = 0.976). However, the comparison of between-playing positions revealed considerable differences in total distance (H = 29.246; p < 0.001), and HSR distance (H = 12.153; p = 0.002) covered by the players acting as starters. In contrast, for substitute players, such differences were reported in HSR distance (H = 27.892; p < 0.001) and sprint distance (H = 15.879; p < 0.001). In conclusion, this study suggests that acting as a starter or a substitute does not significantly affect the intensity of effort except during the last periods of match play. However, the contextual factor of performing in a specific playing position plays a significant role both for starters and substitutes.

Assessing the agreement between a global navigation satellite system and an optical-tracking system for measuring total, high-speed running, and sprint distances in official soccer matches.

This study aimed to compare the agreement of total distance (TD), high-speed running (HSR) distance, and sprint distance during 16 official soccer matches between a global navigation satellite system (GNSS) and an optical-tracking system. A total of 24 male soccer players, who are actively participating in the Polish Ekstraklasa professional league, were included in the analysis conducted during official competitions. The players were systematically monitored using Catapult GNSS (10-Hz, S7) and Tracab optical-tracking system (25-Hz, ChyronHego). TD, HSR distance, sprint distance, HSR count (HSRC), and sprint count (SC) were collected. The data were extracted in 5-min epochs. A statistical approach was employed to visually examine the relationship between the systems based on the same measure. Additionally, R2 was utilized as a metric to quantify the proportion of variance accounted for by a variable. To assess agreement, Bland-Altman plots were visually inspected. The data from both systems were compared using the estimates derived from the intraclass correlation (ICC) test and Pearson product-moment correlation. Finally, a paired t-test was employed to compare the measurements obtained from both systems. The interaction between Catapult and Tracab systems revealed an R2 of 0.717 for TD, 0.512 for HSR distance, 0.647 for sprint distance, 0.349 for HSRC, and 0.261 for SC. The ICC values for absolute agreement between the systems were excellent for TD (ICC = 0.974) and good for HSR distance (ICC = 0.766), sprint distance (ICC = 0.822). The ICC values were not good for HSRCs (ICC = 0.659) and SCs (ICC = 0.640). t-test revealed significant differences between Catapult and Tracab for TD (p < 0.001; d = -0.084), HSR distance (p < 0.001; d = -0.481), sprint distance (p < 0.001; d = -0.513), HSRC (p < 0.001; d = -0.558), and SC (p < 0.001; d = -0.334). Although both systems present acceptable agreement in TD, they may not be perfectly interchangeable, which sports scientists and coaches must consider when using them.

Foam rolling and tissue flossing of the triceps surae muscle: an acute effect on Achilles tendon stiffness, jump height and sprint performance - a randomized controlled trial.

This study aimed to investigate an acute effect of foam rolling and tissue flossing of the Triceps Surae muscle on Achilles tendon stiffness, jump height and sprint performance at different time points. The participants were academic athletes (n = 32) aged between 22 and 24 years; randomly allocated into two groups: foam rolling (ROLL) and tissue flossing (FLOSS). The participants were tested at baseline and 5-min, 15-min, 30-min, 45-min, and 60-min after ROLL and FLOSS for Achilles tendon stiffness (ATstiffeness) at three reference locations: (1) tendon's origin, (2) ankle joint height and (3) intermuscular septum of the gastronomies muscle; countermovement jump (CMJ); and sprint performance at 15-m (SPRINT15 m). The analysis of stiffness revealed a significant decrease in ATstiffness from baseline to Post-60 (p ≤ 0.001) for three locations in the FLOSS group (p ≤ 0.001). In FLOSS, a significant increase was observed from Post-15 to Post-60 (all p≤0.001) in CMJ. We found also a significant decrease in SPRINT15 m in FLOSS in all-time points (p ≤ 0.001), however, SPRINT15 m decreased in Post-5 min, Post-15 min, and Post-30 min (p ≤ 0.001 for all) in ROLL. The current study suggested that both groups enhanced performance up to 60 min after the intervention, caused by mitigating excessive stiffness.

Effects of Open-Skill Exercises on Cognition on Community Dwelling Older Adults: Protocol of a Randomized Controlled Trial.

(1) Cognitive function may benefit from physical exercise in older adults. However, controversy remains over which mode of exercise is more beneficial. (2) The aim of the proposed study is to investigate the effect of open-skill exercise training on cognitive function in community dwelling older adults compared with closed-skill exercise, cognitive training, and active control. (3) One hundred and sixty participants, aged between 60 and 80 years old, will be recruited from community senior centers in Yangzhou, China and randomly assigned to one of four groups: open-skill exercise group, closed-skill exercise group, mobile game playing group, and active control group. All participants will join a 24-week program involving 50 min sessions three times a week. The primary outcome measure is visuospatial working memory. Secondary measures include subjective memory complaint, attention network, nonverbal reasoning ability, and physical activities. All participants will be measured before, mid-way, and immediately after intervention, and three months later. (4) If successful, this study is expected to provide evidence-based recommendations for older adults to select the most efficient and effective mode of exercise to improve cognitive function. Importantly, the three intervention groups provide an opportunity to separate the cognitive activity component from the physical activity component. Comparison of these components is expected to help elucidate possible mechanisms contributing to the additional cognitive benefit of open-skill exercises.

Electromyographic Evaluation of the Shoulder Muscle after a Fatiguing Isokinetic Protocol in Recreational Overhead Athletes.

The goal of our study was to examine the muscle activity of the shoulder girdle after isokinetic fatigue, which may simulate muscle activities commonly occurring during specific sport-related activities in recreational overhead asymptomatic athletes. We hypothesized that exercise-induced fatigue, reported after isokinetic protocols, may cause a decrease in the median frequency (MF) of the upper trapezius (UT), infraspinatus (IS), and deltoid muscles. Twenty-four male overhead volleyball (n = 8), handball (n = 8), and tennis (n = 8) athletes participated in this study. All subjects were without shoulder injury history. The surface electromyography (SEMG) was collected on the right (dominant) side of the shoulder girdle muscles in the following order: UT, IS and anterior (DA), and posterior deltoideus (DP). The fatigue protocol consisted of three sets of 32 maximum isokinetic concentric contractions while performing shoulder internal and external rotation at an isokinetic speed of 120 o/s. The resultant difference in median frequency (ΔMF) values consistently dropped after the fatiguing tasks across all recorded muscles, in terms of the initial MF (MFINI = 65.1 ± 1.1 Hz) and final MF (MFFIN = 57.9 ± 0.9 Hz), and the main effect of time was significant (F(1,22) = 43.15, p < 0.001). MF values decreased mostly for IS (ΔMFIS = -9.9 ± 1.6 Hz) and DP (ΔMFPD = -9.5 ± 1.9 Hz) muscles, while DA and UT showed smaller changes (ΔMFDA = -6.9 ± 1.5 Hz) and (ΔMFUT = -3.2 ± 1.3 Hz). The results of our study show a meaningful contribution in determining increased fatigue of the shoulder girdle muscles during repeated isokinetic internal-external rotation protocols. We have also demonstrated a significant decrease in MF in all examined muscles, especially IS and DA.

Effect of Combined Physical and Cognitive Interventions on Executive Functions in OLDER Adults: A Meta-Analysis of Outcomes.

Background: Both physical exercise and cognitive training can effectively improve executive functions in older adults. However, whether physical activity combined with cognitive training is more effective than a single intervention remains controversial. The aim of this study was to perform a meta-analysis to evaluate the effect of combined physical and cognitive interventions on executive functions in older adults aged 65-80 years old. Methods: Randomized controlled trials of combined physical and cognitive interventions on executive functions in older adults were searched using the Web of Science, Elsevier Science, PubMed, EBSCO, Springer-Link, and NATURE databases. Data extraction and quality evaluation were done by Comprehensive Meta-Analysis, V3. Results: A total of 21 studies were included. The results showed that the combined physical and cognitive interventions produced significantly larger gains in executive functions, compared to the control group (standardized mean difference (SMD) = 0.26, 95% confidence interval (CI) [0.14, 0.39], p < 0.01). Furthermore, the effects of the combined physical and cognitive interventions were moderated by the study quality, intervention length, and intervention frequency. No significant differences were found between the combined interventions and the physical intervention alone (SMD = 0.13, 95% CI [-0.07, 0.33], p > 0.05) or the cognitive intervention alone (SMD = 0.13, 95% CI [-0.05, 0.30], p > 0.05). Conclusions: The combined physical and cognitive interventions effectively delayed the decrease of executive functions in older adults and this effect was influenced by the length and frequency of the intervention as well as the research quality. However, the effect of the combined physical and cognitive interventions was not significantly better than that of each intervention alone.

Changes in Muscle Stiffness of the Trapezius Muscle After Application of Ischemic Compression into Myofascial Trigger Points in Professional Basketball Players.

The study aimed to assess the effects of compression trigger point therapy on the stiffness of the trapezius muscle in professional basketball players (Part A), and the reliability of the MyotonPRO device in clinical evaluation of athletes (Part B). Twelve professional basketball players participated in Part A of the study (mean age: 19.8 ± 2.4 years, body height 197 ± 8.2 cm, body mass: 91.8 ± 11.8 kg), with unilateral neck or shoulder pain at the dominant side. Part B tested twelve right-handed male athletes (mean ± SD; age: 20.4 ± 1.2 years; body height: 178.6 ± 7.7 cm; body mass: 73.2 ± 12.6 kg). Stiffness measurements were obtained directly before and after a single session trigger point compression therapy. Measurements were performed bilaterally over 5 points covering the trapezius muscle. The effects were evaluated using a full-factorial repeated measure ANOVA and the Bonferroni post-hoc test for equal variance. A p-value < .05 was considered significant. The RM ANOVA revealed a significant decrease in muscle stiffness for the upper trapezius muscle. Specifically, muscle stiffness decreased from 243.7 ± 30.5 to 215.0 ± 48.5 N/m (11.8%), (p = .008) (Part A). The test-retest relative reliability of trapezius muscle stiffness was found to be high (ICC from 0.821 to 0.913 for measurement points). The average SEM was 23.59 N/m and the MDC 65.34 N/m, respectively (Part B). The present study showed that a single session of compression trigger point therapy can be used to significantly decrease the stiffness of the upper trapezius among professional basketball players.

Effects of Karate Fights on Achilles Tendon Stiffness Measured by Myotonometry.

The aim of the study was to investigate the influence of karate fights on Achilles tendon stiffness in karate competitors. Eleven male karate fighters participated in the present study. A handheld MyotonPRO device (MyotonPRO, Myoton Ltd, Estonia) was applied to measure Achilles tendon stiffness in karate fighters. The Achilles tendon was tested 5 cm above the tuber calcanei. Stiffness measurements were performed before and after eight sparring fights. Each fight lasted 2 min and was separated by a 2 min rest period. Achilles tendon stiffness for the dominant leg increased significantly from before fights (751.57 ± 123.493 N/m) to immediately after fights (809.43 ± 160.425 N/m) (p = 0.012). Presented results should be used by strength and conditioning coaches in training programs as a way to decrease the risk of injury.