Comparison of bungee-aided and free-bouncing accelerations on trampoline

Trampolines remain the single best apparatus for the training of aerial acrobatics skills. Trampoline use has led to catastrophic injuries from poor landings. Passive injury prevention countermeasures such as specialized matting have been largely ineffective. Active injury countermeasures such as hand spotting, “throw-in” mats, and overhead spotting rigs provide the most effective methods. The recent addition of several bungee cords between the ropes and the gymnast’s spotting harness has resulted in altered teaching and coaching of trampoline-related acrobatics. Bungee cords have eliminated the need for a coach/spotter to manage the ropes during skill learning. The purpose of this study was to assess the influence of the addition of bungee cords with a traditional rope-based overhead spotting rig. There is a paucity of any research involving trampoline injury countermeasures. Ten experienced trampoline acrobatic athletes (5 males, 5 females) from the U.S. Ski and Snowboard Association Aerials National Team performed 10 bounces as high as they could control. A triaxial accelerometer (200 Hz) characterized 10 bungee cord aided bounces and 10 freebounces on a trampoline from each athlete. Bed contact times, peak accelerations, and average accelerations were obtained. The results supported our hypotheses that the bungeeaided bounces achieved only 40% (average) to 70% (peak) of the free-bouncing accelerations (all ρ 0.092). The bed contact time was approximately 65% longer during the bungee-aided bounces (ρ < 0.001). Bungee cords may reduce the harshness of landings on trampoline

Shorter versus longer bouts of rowing-based interval exercise attenuate the physiological and perceptual response

High intensity interval exercise (HIIE) requires repeated bouts of near-maximal to maximal efforts (intensities \u3e 85 %HRmax) interspersed with a brief recovery. Data show superior increases in maximal oxygen uptake (VO 2max) in response to chronic HIIE compared to moderate intensity continuous exercise (MICE) in healthy adults as well as clinical populations (Milanovic et al. 2015; Weston et al., 2014). PURPOSE: This study compared physiological and perceptual variables between short and long durations of rowing-based high intensity interval exercise (HIIE). METHODS: Fourteen active adults (age = 26.4 ± 7.2 yr) performed incremental rowing exercise to fatigue to measure maximal oxygen uptake (VO 2max) and peak power output (PPO). The subsequent 20 min sessions required HIIE (eight 60 s efforts at 85 %PPO with 90 s of active recovery at 20 %PPO or 24 20 s efforts at 85 %PPO with 30 s of active recovery at 20 %PPO) or moderate intensity continuous exercise (MICE) at 40 %PPO. During exercise, VO 2, heart rate (HR), blood lactate concentration (BLa), rating of perceived exertion (RPE), and affective valence were measured. RESULTS: Data show significantly (p \u3c 0.001) higher peak VO 2 (84 ± 7 vs. 76 ± 5 %VO 2peak, d = 0.99), peak HR (94 ± 4 %HRpeak vs. 90 ± 4 %HRpeak, d = 1.12), BLa (7.0 ± 2.5 mM vs. 4.1 ± 1.0 mM, d = 1.22), end-exercise RPE (12.8 ± 2.0 vs. 11.0 ± 1.7, d = 1.29), and lower affective valence (2.1 ± 1.6 vs. 2.9 ± 1.2, d = 0.61) with long versus short HIIE. Time spent above 85 %HRpeak was significantly higher (p \u3c 0.001) in short versus long HIIE (606 ± 259 vs. 448 ± 26 s, d = 0.91). CONCLUSION: Longer rowing-based intervals elicit greater cardiometabolic and perceptual strain versus shorter efforts, making the latter preferable to optimize perceptual responses to HIIE

Surface and waveguide Josephson plasma waves in slabs of layered superconductors

We discuss the propagation of symmetric and antisymmetric Josephson plasma waves in a slab of layered superconductor clad between two identical dielectrics. We predict two branches of surface waves in the terahertz frequency range, one above and another below the Josephson plasma frequency. Apart from this, there exists a discrete set of waveguide modes with electromagnetic fields oscillating across the slab thickness and decaying exponentially away from the slab. We consider the excitation of the predicted waves by means of the attenuated-total-reflection method. It is shown that for a specific set of the parameters of the structure, the excitation of the waveguide modes is accompanied by the total suppression of specular reflection

Assessing interest in artistic gymnastics

Despite information from world media, worldwide interest in artistic gymnastics has never been assessed. Memberships, equipment and apparel purchases, subscriptions, and other data have been used as indirect substitutes for gauging interest and participation in gymnastics. A readily available tool for assessing gymnastics interest could be of use in uncovering myriad trends. Aim of Study: This study sought to use a relatively new internet search tool called Google Trends™ (GT) to assess gymnastics interest by records of search terms used in Google™. Methods: Google™ searches involve the use of search terms that are recorded and then accessible by GT. As GoogleTM searches provide access to topics of interest nearly anywhere in the world, by anyone with internet access, then using Google Trends™, then GT could be used to harvest the number and types of searches involving the search-terms “men’s gymnastics” and “women’s gymnastics.” The tally of the search terms was obtained using filters such as country, region, and others. GT reports the search-term trends by calculating a relative percentage based on a sample of the largest number of specific search-term use during a particular time. Although the relative percentage approach is somewhat awkward, processing large amounts of data may be considered valuable and otherwise unattainable. Results and Conclusions: Results should be interpreted cautiously. However, the analysis revealed a litany of important trends in the worldwide interest in gymnastics

SCS 6th annual meeting—EEVFA—11th international congress of biochemistry and physiology of exercise, Athens, Greece, 2023

On behalf of the Strength and Conditioning Society (SCS) and the Hellenic Society of Biochemistry and Exercise Physiology (EEVFA), we are pleased to present the abstracts of the SCS 6th Annual Meeting and EEVFA—11th International Congress of Biochemistry and Physiology of Exercise. The event was held at the Hellenic Olympic Committee headquarters in Athens, Greece, on 19–22 October 2023, and comprised several invited sessions from international and national speakers on a variety of topics related to biochemistry and exercise physiology, strength and conditioning practices and their application to health, injury prevention and sports performance. These included strength training in high-performance sports, sport science and training–competition load management in elite environments, biochemistry and exercise physiology and prescription, nutrition and biomechanics, among others. The conference also included different practical workshops conducted by renowned academics and practitioners on eccentric training, change of direction ability and strength and power training in professional team-sports, and ergospirometry and exercise prescription in specific populations. Finally, the event disseminated up-to-date strength and conditioning research by providing practitioners and researchers with the opportunity to present their most recent findings. In this regard, all abstracts of the communications presented at the SCS 6th Annual Meeting—EEVFA—11th International Congress of Biochemistry and Physiology of Exercise can be found in this Conference Report

Report on the first Combat Sports Special Interest Group meeting at the 28th Annual Congress of the European College of Sport Science, and call for action

This short report describes the process of creating the Combat Sports Special Interest Group (CSSIG), its first meeting at the 28th Annual Congress of the European College of Sport Science (ECSS, Paris 4-7 July, 2023), and to make a call for action for the next events. The first contact between the group that proposed the creation of the CSSIG was made after a session of the Annual Congress of the ECSS held in 2022, but the idea and format of the proposal was initiated in January 2023. After its approval the CSSIG set the topics for the first meeting. During the 2023 edition the ECSS event had eight special interest groups, including the CSSIG. The first meeting of the CSSIG included the presentation of its goals, and two short presentations: one related to combat sports athletes’ health, and the other on testing and training monitoring of judo athletes. The aim of the CSSIG is to establish a sustainable network fostering evidence-based research and practice of combat sports, in order to: (a) promote health and safety of combat sports participants, (b) enhance their performance, and (c) improve training and competition practices. Thus, this report is also a call for action for the next events

Effects of two workload-matched high-intensity interval training protocols on regional body composition and fat oxidation in obese men

© 2021 The Authors. Published by MDPI. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.3390/nu13041096The effects of two high-intensity interval training (HIIT) protocols on regional body composition and fat oxidation in men with obesity were compared using a parallel randomized design. Sixteen inactive males (age, 38.9 ± 7.3 years; body fat, 31.8 ± 3.9%; peak oxygen uptake, VO2peak, 30.9 ± 4.1 mL/kg/min; all mean ± SD) were randomly assigned to either HIIT10 (48 × 10 s bouts at 100% of peak power [Wpeak] with 15 s of recovery) or HIIT60 group (8 × 60 s bouts at 100% Wpeak with 90 s of recovery), and subsequently completed eight weeks of training, while maintaining the same diet. Analyses of variance (ANOVA) showed only a main effect of time (p 0.05) in the examined parameters. Total and trunk fat mass decreased by 1.81 kg (90%CI: −2.63 to −0.99 kg; p = 0.002) and 1.45 kg (90%CI: −1.95 to −0.94 kg; p < 0.001), respectively, while leg lean mass increased by 0.86 kg (90%CI: 0.63 to 1.08 kg; p < 0.001), following both HIIT protocols. HIIT increased peak fat oxidation (PFO) (from 0.20 ± 0.05 to 0.33 ± 0.08 g/min, p = 0.001), as well as fat oxidation over a wide range of submaximal exercise intensities, and shifted PFO to higher intensity (from 33.6 ± 4.6 to 37.6 ± 6.7% VO2peak, p = 0.039). HIIT, irrespective of protocol, improved VO2peak by 20.0 ± 7.2% (p < 0.001), while blood lactate at various submaximal intensities decreased by 20.6% (p = 0.001). In conclusion, both HIIT protocols were equally effective in improving regional body composition and fat oxidation during exercise in obese men.This work is part of the research project “SAFE PATH” (Stand up And Fight obEsity: Promoting Aerobic Training and Health) and was funded by The Coca-Cola Company.Published versio

Effects of blood flow restriction on mechanical properties of the rectus femoris muscle at rest

Introduction: This study examined the effects of blood flow restriction (BFR) and reperfusion on the mechanical properties of the rectus femoris muscle at rest (frequency and stiffness).Methods: Fourteen trained men (body weight = 81.0 ± 10.3 kg; BMI = 25 ± 3.0 m/kg2; height = 181 ± 4 cm; training experience = 6.0 ± 2.2 years) participated in an experimental session involving their dominant (BFR) and non-dominant leg (control). Muscle mechanical properties were measured using Myoton’s accelerometer at the midpoint of the rectus femoris muscle at five time points. In the BFR leg, an 80% arterial occlusion pressure was applied by a cuff for 5 min. No cuff was applied in the control leg. Femoral Myoton measurements were taken from both legs 2 and 4 min after the start of BRF as well as 30 s and 2 min after the end of the occlusion period.Results: The two-way ANOVA revealed a statistically significant interaction effect for stiffness and frequency (p &lt; 0.001; η2 &gt; 0.67). The post hoc analysis showed that both stiffness and frequency increased during BFR compared with rest and then dropped to the resting levels post BFR period. Also, stiffness and frequency were higher than control only during the BFR period, and similar during rest and post BFR.Conclusion: These results indicate that the application of BFR at rest leads to significant changes in mechanical properties of the rectus femoris muscle

A pilot study comparing the metabolic profiles of elite-level athletes from different sporting disciplines

Background: The outstanding performance of an elite athlete might be associated with changes in their blood metabolic profile. The aims of this study were to compare the blood metabolic profiles between moderate- and high-power and endurance elite athletes and to identify the potential metabolic pathways underlying these differences. Methods: Metabolic profiling of serum samples from 191 elite athletes from different sports disciplines (121 high- and 70 moderate-endurance athletes, including 44 high- and 144 moderate-power athletes), who participated in national or international sports events and tested negative for doping abuse at anti-doping laboratories, was performed using non-targeted metabolomics-based mass spectroscopy combined with ultrahigh-performance liquid chromatography. Multivariate analysis was conducted using orthogonal partial least squares discriminant analysis. Differences in metabolic levels between high- and moderate-power and endurance sports were assessed by univariate linear models. Results: Out of 743 analyzed metabolites, gamma-glutamyl amino acids were significantly reduced in both high-power and high-endurance athletes compared to moderate counterparts, indicating active glutathione cycle. High-endurance athletes exhibited significant increases in the levels of several sex hormone steroids involved in testosterone and progesterone synthesis, but decreases in diacylglycerols and ecosanoids. High-power athletes had increased levels of phospholipids and xanthine metabolites compared to moderate-power counterparts. Conclusions: This pilot data provides evidence that high-power and high-endurance athletes exhibit a distinct metabolic profile that reflects steroid biosynthesis, fatty acid metabolism, oxidative stress, and energy-related metabolites. Replication studies are warranted to confirm differences in the metabolic profiles associated with athletes’ elite performance in independent data sets, aiming ultimately for deeper understanding of the underlying biochemical processes that could be utilized as biomarkers with potential therapeutic implications