This study investigated PAPE effects of two conditioning activities (CA) and recovery times on the peak jumping power (PP) of elite female volleyball athletes. Players performed CA separately: three sets of three repetitions of back squats with 85% of 1RM (BS) or one set of five depth drops (DD). PP was measured with countermovement (CMJ) and squat jumps (SJ) before (pre-test) and two minutes (post-test 1) and six hours (post-test 2) after each CA. BS significantly reduced PP at post-test 1 (CMJ and SJ: p < 0.04, d between −0.36 and −0.28). At post-test 2, following BS, PP for both jump forms was significantly greater than at post-test 1 (p < 0.001, d between 0.54 and 0.55) and at pre-test (p < 0.048, d between 0.21 and 0.30). DD increased PP significantly (CMJ and SJ p < 0.05, d between 0.40 and 0.41) relative to pre-test at post-test 2 (there was no significant difference between pre-test and post-test 1). Comparing BS with DD, there were no significant differences (p > 0.05). The greatest PAPE effects were observed six hours after BS. CA are recommended for female athletes to improve jumping performance, but individual responses should be determined prior to use.
Two methods for challenging the musculoskeletal and nervous systems to better exploit the stretch-shortening cycle (SSC) mechanism during plyometric training are reactive strength exercises and accentuated eccentric loading (AEL). Combining repetitive, reactive jumping with AEL poses a novel approach, in which the effects of both methods may be combined to elicit a unique stimulus. This study compared kinematic, kinetic, and electromyographic variables between a control (CON1) and two AEL conditions (AEL2 and AEL3). Additionally, non-reactive and reactive jumps performed within these sets were compared. Participants performed two sets of six countermovement jumps (CMJ) under each loading condition. AEL3 had moderate to large positive effects (es) on peak and mean eccentric force (es = 1.1, 0.8, respectively; both; p; < 0.01), and eccentric loading rate (es = 0.8,; p; < 0.01), but no effect on concentric variables or muscle activation intensity. The effects of AEL2 were similar but smaller. With or without AEL, there were moderate to large positive effects associated with reactive CMJ (second jump in a set, compared to the first) on peak and mean eccentric velocity (es = 1.7, 0.8, respectively; both; p; < 0.01), peak and mean eccentric force (es = 1.3, 1.2,; p; < 0.01), eccentric loading rate (es = 1.3,; p; < 0.01) and muscle activity (es = 1.8-1.9,; p; < 0.01). Concentric variables did not differ. Thus, the flight phase and act of landing during reactive jumps elicited greater increases in eccentric forces, loading rates, and muscle activity than AEL. Nonetheless, kinetic variables were greatest when AEL was combined with reactive jumping. Considering the limitations or complexity associated with most AEL protocols, sets of repetitive (reactive) CMJ may be more pragmatic for augmenting eccentric kinetic variables and neuromuscular stimuli during training.
Performance on vault in artistic gymnastics depends on the difficulty and the execution quality of the performed vault. However, differences of kinetic energy between simple and difficult vaults remain elusive. Therefore, in this study, 48 Tsukahara and Yurchenko vaults, performed by 20 top-level gymnasts, were recorded with 3D-motion capture and the flux of translational (TKE), angular kinetic (AKE), potential (PE), and total energy were calculated and compared. Results revealed that upon initial springboard contact, almost all of the kinetic energy for Tsukahara vaults is comprised of TKE, whereas Yurchenko vaults were characterized by substantially less TKE, but far greater AKE (and similar PE). During springboard contact of Tsukahara vaults, AKE is increased (+70%) and thereafter mostly preserved during push off from the table (−6%). For Yurchenko vaults, AKE is preserved during springboard contact but reduced (−30%) in exchange for PE at push off. During the second flight phase of Yurchenko vaults, total energy was 10% higher than at initial springboard contact (Tsukahara: −1%). For vaults of increasing difficulty, 5.9% more AKE is needed for each additional 180° of longitudinal-axis rotation. This knowledge may help coaches evaluate athletes’ potential and focus training on appropriate physical and/or technical aspects of the vault performance.
On rings, in men's artistic gymnastics, the general strength requirements for important static elements remain elusive. Therefore, the aim was to describe the relationship between a new conditioning strength test and a maximum strength test of static elements on rings in order to determine the minimal strength level (benchmarks) required to maintain these elements with one's own body weight. Nineteen elite gymnasts performed a concentric (1RM isoinertial) and eccentric (isokinetic: 0.1 m/s) conditioning strength test for swallow/support scale (supine position) and inverted cross (seated position) on a computer-controlled device and a maximum strength test maintaining these elements for 5 s on rings with counterweight or additional weight. High correlation coefficients were found between the conditioning maximum strength for swallow/support scale (r: 0.65 to 0.92; p < 0.05) and inverted cross (r: 0.62 to 0.69; p > 0.05) and the maximum strength of the elements on rings. Strength benchmarks varied between 56.66% (inverted cross concentric) and 94.10% (swallow eccentric) of body weight. Differences in biomechanical characteristics and technical requirements of strength elements on rings may (inter alia) explain the differences between correlations. Benchmarks of conditioning strength may help coaches and athletes systematize the training of strength elements on rings.
Die vorliegende Dissertation liefert im Kunstturnen am Pferdsprung der Männer und Frauen und an den Ringen Erkenntnisse für das sportliche Training, die sportliche Leistung und den sportlichen Wettkampf sowie deren gegenseitigen Wechselbeziehungen. Dieses Wissen kann zur besseren Steuerung und Optimierung des Trainings im Nachwuchs- und Elite-Kunstturnen beitragen.
We are glad to introduce the Journal Club of Volume Five, fourth Issue. This edition is focused on relevant studies published in the last few years in the field of corrective exercise, chosen by our Editorial Board members and their colleagues. We hope to stimulate your curiosity in this field and to share a passion for sport with you, seen also from the scientific point of view. The Editorial Board members wish you an inspiring lecture.
max. 250 Wörter / 250 mots au max. Einleitung / Introduction: Ein Monitoring der Trainingsbelastung und der Leistungsanpassungen dient unter anderem der Optimierung des Trainings. Das Ziel dieser Untersuchung war deshalb, basierend auf den Erkenntnissen aus der Trainingsdatenanalyse der exzentrisch-isokinetischen Krafttrainingsintervention zur Verbesserung von Krafthalteelementen an den Ringen im Kunstturnen (Schärer et al. 2019; Studie 1), eine optimierte Trainingsintervention zu entwickeln sowie ihre Wirksamkeit zu überprüfen (Studie 2). Methode / Méthode: Die Analyse der vierwöchigen Trainingsintervention (acht Trainings) mit dem 1080 Quantum Syncro (Studie 1) ergab, dass sich die exzentrische Maximalkraft hauptsächlich in den Trainings 2 bis 4 verbessert hat. Die Trainingsübung (Rückenlage auf Heberbank, Hände greifen je einen Ring wie beim Kunstturnen, maximaler Gegendruck mit gestreckten Armen (Ausgangsposition: 70° über Hüfte; Endposition: -15° unter Hüfte) gegen das mit 0.1m/s computergesteuert nach unten synchron eingezogene Zugseil) sowie die "cluster-förmige" exzentrisch-isokinetische Belastungsmodalität dieser drei Trainings (Training 2: 2x2x4; Trainings 3 und 4: 3x3x4) wurden deshalb in der dreiwöchigen Intervention von Studie 2 von Training 1 bis 3 übernommen und als Reizwechsel von Training 4 bis 6 exzentrisch-isokinetisch + isoinertial mit zehn Nationalkaderathleten wiederholt. Eine Woche vor und nach Trainingsintervention wurde der maximale Widerstand (Körpergewicht plus Zusatzgewicht / minus Gegengewicht) bei den Krafthalteelementen Schwalbe und Stützwaage an den Ringen (Haltezeit: 5s) bestimmt. Resultate / Résultats: Die Maximalkraft der Krafthalteelemente verbesserte sich in Studie 2 um 7% (Stützwaage) respektive 8% (Schwalbe) (beide p < 0.01), in Studie 1 um 4% (Stützwaage; p < 0.01) respektive 3% (Schwalbe p > 0.05). Diskussion und Schlussfolgerung / Discussion et conclusion: Die Effizienz der Trainingsintervention in Studie 2 konnte dank dem Trainingsmonitoring von Studie 1 (mit zwei Trainings weniger) verdoppelt werden. Diese Studie zeigt, wie durch Monitoring "nicht-funktionale Trainingsreize" eliminiert und dadurch Krafttrainingsinterventionen effizienter gestaltet werden können. In Bezug auf die angewandte exzentrisch-isokinetische Trainingsform konnte festgestellt werden, dass diese bei Eliteathleten hochwirksam zu sein scheint, wenn erstens eine gewisse (minimale) Wiederholungsanzahl der Trainingsübung pro Training realisiert wird und zweitens ein Reizwechsel (exzentrsich-isokinetisch + isoinertial) nach nur wenigen Trainings stattfindet. Aufgrund der hohen Intensität sollte diese Trainingsform nicht als "Dauermethode", jedoch gezielt in Phasen mit geringer Belastung im sporttechnischen Training eingesetzt werden.
As hill jumps are very time-consuming, ski jumping athletes often perform various imitation jumps during training. The performed jumps should be similar to hill jumps, but a direct comparison of the kinetic and kinematic parameters has not been performed yet. Therefore, this study aimed to correlate 11 common parameters during hill jumps (Oberstdorf Germany), squat jumps (wearing indoor shoes), and various imitation jumps (rolling 4°, rolling flat, static; jumping equipment or indoor shoes) on a custom-built instrumented vehicle with a catch by the coach. During the performed jumps, force and video data of the take-off of 10 athletes were measured. The imitation and squat jumps were then ranked. The main difference between the hill jumps and the imitation and squat jumps is the higher maximal force loading rate during the hill jumps. Imitation jumps performed on a rolling platform, on flat ground were the most similar to hill jumps in terms of the force-time, and leg joint kinematic properties. Thus, non-hill jumps with a technical focus should be performed from a rolling platform with a flat inrun with normal indoor shoes or jumping equipment, and high normal force loading rates should be the main focus of imitation training.
On vault in artistic gymnastics, a high run-up speed is thought to be important when performing difficult vaults. To test this assumption in a large cohort of elite athletes, we calculated the correlations between the run-up speed, scores, height and length of flight for handspring-, Tsukahara- and Yurchenko-style vaults and compared the performances of male and female elite and junior athletes (n = 407) during the 2016 European Championships. In females, run-up speed correlated significantly with the difficulty (D-) score and height of flight for all vaulting styles (r ≤ 0.80). In males, run-up speed correlated significantly with the D-score, height and length of flight of Tsukahara (r ≤ 0.69) and Yurchenko vaults only (r ≤ 0.65). Males reached 8-9% higher run-up speeds performing handspring and Tsukahara vaults than did females, but similar run-up speeds performing Yurchenko vaults. Elite females achieved higher run-up speeds than junior females performing Yurchenko vaults. Elite males displayed higher run-up speeds than junior males performing handspring and Tsukahara vaults. We conclude that, in females, more difficult vaults require higher run-up speeds than vaults with lower D-scores and thus, within the measured range of speeds, the faster the run-up, the better, regardless of vaulting style. Males, on the other hand, may not need to exhaust their sprinting capacity, even for the most difficult vaults. Finally, the knowledge of the required run-up speed for each vault helps coaches to estimate each athlete's potential and/or to focus the training on developing the required physical qualities.
In artistic gymnastics, the possibility of using 2D video analysis to measure the peak height (hpeak) and length of flight (L) during routine training in order to monitor the execution and development of difficult elements is intriguing. However, the validity and reliability of such measurements remain unclear. Therefore, in this study, the hpeak and L of 38 vaults, performed by top-level gymnasts, were assessed by 2D and 3D analysis in order to evaluate criterion validity and both intrarater and interrater reliability of the 2D method. Validity calculations showed higher accuracy for hpeak (±95% LoA: ±3.6% of average peak height) than for L (±95% LoA: ±7.6% of average length). Minor random errors, but no systematic errors, were observed in the examination of intrarater reliability (hpeak: CV% = 0.44%, p = 0.81; L: CV% = 0.87%, p = 0.14) and interrater reliability (hpeak: CV% = 0.51%, p = 0.55; L: CV% = 0.72%, p = 0.44). In conclusion, the validity and reliability of the 2D method are deemed sufficient (particularly for hpeak, but with some limitations for L) to justify its use in routine training of the vault. Due to its simplicity and low cost, this method could be an attractive monitoring tool for gymnastics coaches.
In order to perform difficult vaults in artistic gymnastics, athletes have to achieve high run-up speeds within the limited run-up distance (25m). However, the physical parameters that contribute to a high run-up speed and their age-related differences remain elusive. Hence, the aim of this study was 1) to investigate interrelations between difficulty value (D-score) and run-up kinematics of Handspring/Tsukahara and Yurchenko vaults as well as lower body power (25m-sprint, explosive and reactive strength) and 2) to explore age-related differences of these parameters across junior and elite gymnasts performing Handspring/Tsukahara vaults. For this purpose, the data (of the above mentioned parameters) of 47 top-level male elite and junior gymnasts aged 14.3 to 28.3 of performance testing, gathered over three years, were analysed. We found that D-score of Handspring/Tsukahara (n = 33) was strongly correlated with run-up speed (r = 0.79; p < 0.01). Further, 25m sprint speed (r = 0.85; p < 0.01) was significantly associated with run-up speed of Handspring/Tsukahara-vaults. There were no significant relationships with the D-score of Yurchenko (n = 14). Looking at the age-related differences of Handspring/Tsukahara, D-score increased significantly from junior to elite level (+11.6%; p < 0.01). The comparison between consecutive age-groups revealed that the U19 group had higher run-up speeds, step lengths, body weights and heights than the U17 group, while the U21 group achieved significantly higher speeds (run-up, 25m-sprint) and explosive strength than the U19 group. We concluded 1) that the optimization of important physical determinants may increase the potential to perform more difficult Handspring/Tsukahara vaults and 2) that first growth and maturation and later improvements of lower body power led to higher run-up speeds of Handspring/Tsukahara in the subsequent age-group. Therefore, based on performance testing of the lower limbs, training recommendations should be given specifically to the requirements of the competition vault.
In gymnastics, coaches are constantly searching for efficient training methods in order to improve the athletes' performance. Therefore, in this study we aimed to investigate the effects of a novel, four-week, gymnastic-specific, eccentric-isokinetic (0.1 m/s) cluster training on a computer-controlled training device on the improvement of two static strength elements on rings (swallow and support scale). Nine elite male gymnasts participated in this study. Outcome parameters were maximum strength and strength endurance in maintaining the static position of both elements. After four weeks of training, specific maximum strength increased significantly (swallow: +4.1%;; d; = 0.85;; p; = 0.01; support scale: +3.6%;; d; = 2.47;; p; = 0.0002) and strength endurance tended to improve (swallow: +104.8%;; d; = 0.60;; p; = 0.07; support scale: +26.8%;; d; = 0.27;; p; = 0.19). Our results demonstrate that top athletes can considerably improve ring-specific strength and strength endurance in only four weeks. We assumed that the high specificity but also the unfamiliar stimulus of slow eccentric movements with very long times under maximal muscle tension led to these improvements. We suggest to use this type of training periodically and during phases in which the technical training load is low.