Attentional focus strategies eliciting external focus of attention effectively enhance drop jump (DJ) performance, however, their effects vary depending on the words used for the instructions. We aimed to examine the effects of different words on DJ performance using instructions eliciting external focus to minimize contact time (CT) or maximize jump height (JH). Twenty collegiate athletes performed DJs from a 30-cm platform after receiving one of the four instructions: two instructions (COND 1 and 2) about minimizing CT, and two instructions (COND 3 and 4) about maximizing JH. The reactive strength index (RSI), CT, JH, relative peak vertical ground reaction force (vGRF), and leg stiffness (kvert) were compared between conditions using repeated-measures analysis of variance. There was no significant main effect of conditions on the RSI, relative peak vGRF, and kvert (p > 0.05). CT was significantly shorter under CONDs 1 and 2 than COND 3 (p < 0.05); JH was significantly higher under COND 3 than CONDs 1 and 2 (p < 0.05), and under COND 4 than COND 1 (p < 0.05). When using attentional focus strategies in DJ, it is necessary to use different words and purposes according to the players' tasks.
Abstract Franchini, E, Cormack, S, and Takito, MY. Effects of high-intensity interval training on Olympic combat sports athletes' performance and physiological adaptation: A systematic review. J Strength Cond Res 33(1): 242–252, 2019—Combat sports represent around 25% of all Olympic medals disputed, and the success in these sports are determined by technical-tactical excellence and supported by physiological and psychological development. Although the training in combat sports is intermittent training by nature, some researchers have started to focus their attention on the effects of complementary high-intensity interval training (HIIT)-coupled standard combat sports-specific training on morphological, physiological, and performance adaptations. Thus, in this systematic review, we aimed to verify the effects of this type of training on these variables. A total of 117 articles in the electronic databases Pubmed, Scopus, and Web of Science were retrieved, and 9 studies remained in the present systematic review. A total of 228 athletes (138 judo athletes, 40 taekwondo athletes, 18 boxers, 17 karate athletes, and 15 wrestlers) were investigated in these 9 studies (5 with judo athletes, 1 with boxers, 1 with karate athletes, 1 with wrestlers, and 1 with taekwondo athletes). The HIIT protocols investigated did not generate any change in body fat percentage or body mass but generally resulted in increases in max or peak, varying from 4.4 to 23.0%. However, the most observed benefit of HIIT protocols was an increase in anaerobic fitness, represented by improvements in anaerobic power and capacity.
Resumen: El movimiento olímpico manifiesta desde sus orígenes unos objetivos y unos valores que constituyen su razón de ser. En este trabajo se exponen los valores que inspiraron a Coubertin y a cuya promoción sirve el Movimiento Olímpico, así como su plasmación concreta en la Carta Olímpica. Esta plasmación en la Carta Olímpica se acompaña de un estudio sistemático de la evolución de la Carta y los valores en ella recogidos para determinar la vigencia del pensamiento de Coubertin en la misma, así como el planteamiento de su carácter de “Constitución transnacional”, junto a los retos de futuro que todavía se plantean. Abstract:The Olympic movement has manifested, since its origins, objectives and values that constitute its raison d'être. This paper presents the values that inspired Coubertin and whose promotion the Olympic Movement serves, as well as their concrete embodiment in the Olympic Charter. The Charter is accompanied by a systematic study of the evolution of the Charter and the values it embodies in order to determine the relevance of the Olympic Movement's values. The evolution of the Charter and the values contained therein to determine the relevance of Coubertin's thinking in the Charter, so its character as a "transnational Constitution”, as well as the challenges tofo the future that still remain.
Abstract Beato, M, Devereux, G, and Stiff, A. Validity and reliability of global positioning system units (STATSports Viper) for measuring distance and peak speed in sports. J Strength Cond Res 32(10): 2831–2837, 2018—Previous evidence has proven that large variability exists in the accuracy of different brands of global positioning systems (GPS). Therefore, any GPS model should be validated independently, and the results of a specific brand cannot be extended to others. The aim of this study is to assess the validity and reliability of GPS units (STATSports Viper) for measuring distance and peak speed in sports. Twenty participants were enrolled (age 21 ± 2 years [range 18 to 24 years], body mass 73 ± 5 kg, and height 1.78 ± 0.04 m). Global positioning system validity was evaluated by comparing the instantaneous values of speed (peak speed) determined by GPS (10 Hz, Viper Units; STATSports, Newry, Ireland) with those determined by a radar gun during a 20-m sprint. Data were analyzed using the Stalker (34.7 GHz, USA) ATS Version 5.0.3.0 software as gold standard. Distance recorded by GPS was also compared with a known circuit distance (400-m running, 128.5-m sports-specific circuit, and 20-m linear running). The distance bias in the 400-m trial, 128.5-m circuit, and 20-m trial was 1.99 ± 1.81%, 2.7 ± 1.2%, and 1.26 ± 1.04%, respectively. Peak speed measured by the GPS was 26.3 ± 2.4 km·h−1, and criterion was 26.1 ± 2.6 km·h−1, with a bias of 1.80 ± 1.93%. The major finding of this study was that GPS did not underestimate the criterion distance during a 400-m trial, 128.5-m circuit, and 20-m trial, as well as peak speed. Small errors (<5%, good) were found for peak speed and distances. This study supported the validity and reliability of this GPS model.
In this paper a property which can be used to measure and category named fuzzy soft \(\beta\)-Baire spaces in fuzzy soft Topological spaces is investigated. For this purpose fuzzy soft \(\beta\)-dense, nowhere fuzzy soft \(\beta\)-dense and fuzzy soft \(\beta\)-first category sets are defined and some results about these concepts are also obtained.
Although numerous studies have convincingly demonstrated that sleep plays a critical role in motor sequence learning (MSL) consolidation, the specific contribution of the different sleep stages in this type of memory consolidation is still contentious. To probe the role of stage 2 non-REM sleep (NREM2) in this process, we used a conditioning protocol in three different groups of participants who either received an odor during initial training on a motor sequence learning task and were re-exposed to this odor during different sleep stages of the post-training night (i.e., NREM2 sleep [Cond-NREM2], REM sleep [Cond-REM], or were not conditioned during learning but exposed to the odor during NREM2 [NoCond]). Results show that the Cond-NREM2 group had significantly higher gains in performance at retest than both the Cond-REM and NoCond groups. Also, only the Cond-NREM2 group yielded significant changes in sleep spindle characteristics during cueing. Finally, we found that a change in frequency of sleep spindles during cued-memory reactivation mediated the relationship between the experimental groups and gains in performance the next day. These findings strongly suggest that cued-memory reactivation during NREM2 sleep triggers an increase in sleep spindle activity that is then related to the consolidation of motor sequence memories.
Abstract Barr, M, Beaver, T, Turczyn, D, and Cornish, S. Validity and reliability of 15 Hz global positioning system units for assessing the activity profiles of university football players. J Strength Cond Res 33(5): 1371–1379, 2019—Global positioning system (GPS) units have recently become popular for monitoring and assessing the workloads of football players. Currently, there is a lack of studies examining the validity and reliability of these systems for that purpose, so the aim of the current study was to determine whether 15 Hz units (SPI HPU; GPSports, Canberra, Australia) could accurately be used to describe the physical demands of football. A series of cohort studies were conducted with Canadian university football players (n = 28). To assess the accuracy of the units' ability to measure high-velocity sprinting, 12 players performed multiple electronically timed 36.6 m sprints while wearing the units. To assess the interunit reliability, 5 players wore 2 units each during a training session. An analysis of the units' validity for measuring collisions was performed by comparing the correct number of tackles and blocks notated on video by an expert rater in 2 games with the number of collisions recorded by the units. The units were accurate for measuring high-sprinting velocities (coefficient of variation [CV] = 0.9%) and had good interunit reliability for recording distances at velocities between walking and sprinting CV (1.4–7.8%). The collision algorithm filter the accompanying software uses was found to have its best balance between precision and recall using a cut-off of 2.65g for linemen and 2.9g for nonlinemen. The devices used are effective at providing acceptably valid and reliable information to describe the physical demands of football. Position-specific locomotor zones are recommended when using GPS units with football players.
In this paper, we have studied the various operations of interval valued anti fuzzy soft subhemirings of a hemiring to establish their basic properties. We have discussed different algebraic structures of interval valued anti-fuzzy soft subhemirings of a hemiring under the restricted and extended operations. Product and strongest relation have also been made in order to give a complete overview of these structures.
In the present paper the concept of soft almost semi-continuous mappings and soft almost semi-open mappings in soft topological spaces have been introduced and studied.