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INTRODUCTION:Snowboarding is an increasingly popular sport, but it has been little studied so far, especially regarding the biomechanical characteristics (1). Most previous research concerned injury occurrence, the physiological profile of the snowboarding athletes (1) and dynamic variables characterizing the turn (2,3). Therefore, the aim of this study was to compare the turn technique of the snowboard giant slalom between elite and experienced recreational athletes, to improve the knowledge of performance factors and to provide suggestions to athletes and coaches. METHODS: Eight male snowboarders, four belonging to the Italian Snowboard National Team (EA, age 27±3.2y, height 1.80±0.10 m, mass 83.4±4.3 kg) and four experienced recreational athletes (RA, age 41.5±5.5 y, height 1.76±0.03 m, mass 89.0±12.2 kg) were analyzed during two performance on a snowboard slope (14 gates spaced at 21 m, 200m total descent). Eight wearable inertial and magnetic measurement units (APDM Opals, 128 Hz) were used for data collection. The sensors were fixed on sternum, sacrum, thigh, leg, toe of ski boot (right and left). Snowboarders were filmed when passing through the first 4 gates using a video camera (JVC full HD, 250hz) to compare the video recordings and the inertial sensor signal, and to define an algorithm to identifies automatically the transition of the gate and the change of the ski edge of all turns. These events were used to divide the turn in 4 phases: from change of ski edge to gate (T1) and from gate to change of ski edge (T2). Each event was identified for the backside-B and frontside-F turn, defining this way T1B, T2B, T1F, T2F respectively. RESULTS: Concerning time variables, EA showed shorter and more consistent times than RA in all turn phases (T1B 0.89±0.18s vs 0.99±0.11s, T2B 0.97±0.21s vs 1.53±0.50s, T1F 0.65±0.19s vs 1.23±0.3s, T2F 0.97±0.19s vs 1.31±0.22s), with significant differences (p

L’articolo mette a confronto i migliori atleti italiani di sesso maschile di getto del peso delle categorie Allievi e Assoluti praticanti la tecnica lineare. Lo scopo è cercare di spiegare l’evoluzione della tecnica dal settore giovanile a quello assoluto per identificare i parametri essenziali della prestazione. I lanci degli atleti, ripresi durante i Campionati Italiani di Categoria, sono stati analizzati tramite SIMI Motion. Sono state valutate le variabili temporali e cinematiche dei migliori atleti. Da quanto è emerso non ci sono particolari differenze tecniche tra Allievi e Senior, ma molti parametri di tutti gli atleti non sono in linea con quelli identificati in letteratura come fondamentali per la performance. Pertanto si ritiene necessaria nel passaggio tra le due categorie un maggior miglioramento tecnico per potere allineare le prestazioni degli atleti italiani a quelli World Class.

Il successo o meno di uno sprinter durante la stagione sportiva è legato non solo ad una corretta pianificazione dei mezzi e dei contenuti dell’allenamento, ma anche alla propria integrità fisica. Diventa prioritario pertanto da parte dell’allenatore cercare di prevenire gli infortuni del proprio atleta. A questo proposito, tra gli infortuni più frequenti nello sprint risultano quelli ai muscoli ischiocrurali. Secondo la letteratura più recente, le cause più probabili di tali infortuni sono legate ad uno squilibrio di forza tra quadricipite e ischiocrurali, ad un errato automatismo tecnico o ad un comportamento asimmetrico degli arti inferiori durante la corsa. Proprio su quest’ultima causa si stanno concentrando le ricerche di molti studiosi e si inserisce anche questo studio pilota che analizza, tramite l’optojump ed una ricostruzione tridimensionale del movimento (SIMI Motion System), i parametri cinematici lineari ed angolari nonché i dati temporali di 4 velocisti di livello nazionale durante una prova di corsa alla massima velocità. Le maggiori asimmetrie (indice di asimmetria SA superiore al 15%) si sono riscontrate soprattutto nei ROM articolari di ginocchio e caviglia e nella massima estensione dell’anca. I risultati sembrano dimostrare come l’asimmetria possa configurarsi sia come causa, ma anche come effetto degli infortuni agli ischiocrurali. A rinforzo di questa ipotesi, uno dei soggetti analizzati, che successivamente all’elaborazione dei dati, ha mostrato diversi parametri asimmetrici, proprio durante la sessione di acquisizione ha accusato un infortunio al comparto posteriore della coscia. Ai fini pratici, pertanto, potrebbe essere importante fotografare la situazione tecnica e fisica dello sprinter all’inizio della nuova stagione agonistica, in modo da provare a ripristinare, qualora ce ne fosse bisogno, una corretta simmetria di corsa prima di incominciare a sottoporre l’atleta a nuovi carichi di allenamento. Per far sì però che la ricerca possa effettivamente fornire agli allenatori ed agli atleti dei dati generalizzabili sull’asimmetria e sul collegamento tra questa e gli infortuni agli ischiocrurali, sono necessari ancora molti studi che coinvolgano un numero maggiore di atleti, differenziandone i livelli prestativi, seguendone la carriera longitudinalmente ed analizzando anche le possibili differenze di genere.

The goal of this study is of comparing athletes belonging to youth and senior categories, during the execution of the rotatory technique of shot put, and comparing them with the values recorded in literature for top level athletes, with the aim of observing how the most important kinematic parameters evolve and trying to understand the reason why since many years senior Italian athletes are no more at the top in the most important international events. The videos of the first two athletes, executing the rotatory technique, were acquired at the Italian Youth and Senior Championships. Through the three-dimensional system SIMI Motion (Simi Reality Motion Systems GmbH, Unterschleissheim, Germania) the time and kinematic variables of the throw were identified. The results show that young athletes have a technical incorrect behaviour in comparison with expert athletes, especially as to the body position, in the phases preceding the tool release. This study can offer to coaches some suggestions to try to correct some of the outlined individual mistakes.

Introduction Decathlon is one of the most challenging disciplines in track and field. Previous studies have assessed the relationships between the performance in the 10 decathlon events by means of correlations or cluster analyses (Woolf et al, 2007, Cox et al, 2002, Van Damme et al, 2000). The aim of this study was to assess the correlations between the 10 decathlon events and the final competitive outcome, with particular focus on possible strategies used to achieve the final score by athletes of the most represented nations in the top 100 all-time world ranking. Methods The 100 world top (all-time) decathlon performances (taken from IAAF scores) were analysed. Scores achieved before the change of the javelin throw rule in 1986, have been compared to the results obtained after 1986, after standardization of the different throwing results according to Borgström (2000). The ranking has been analyzed to investigate how the different events are clustered and affect the final score. Furthermore, the data of the 3 states with the highest number of athletes in the all-time list (Russia, Germany and USA) were compared to study how their training strategies may affect the final performance. Results In agreement with previous studies (Cox et al, 2002, Woolf et al, 2007), the analysis showed two main clusters observed in the dendrograms. The 100m, 110m hurdles and long jump belonged to the same cluster and their scores were well correlated with the final results (r between 0.536 and 0.564). The shot put and discus throw were linked to another cluster, and were not correlated with the final score. The javelin throw, the pole vault and the high jump showed a weaker relationship with the final score, probably due to the high level of technical skill required. There were no significant differences between the three examined nations , with the exception of the average 100m and 1500m results between Russia and USA (851 pts vs. 892pts, and 745 pts vs. 702 pts, respectively). Discussion The results show that the sprint events influence the decathlon performance more than other events. This outcome may be taken into account to select talents and develop a more effective training programs. Among the 3 examined nations, USA showed higher score than the Russia especially in the sprint events and consequently in the final score. Russia showed better scores in the throwing events and 1500m race. Finally, athletes from Germany were generally ranked between those of the other 2 nations in all the decathlon events. References Borgström A (2000). New Studies in Athletics, 15, 3/4, 25-28. Cox TF, Dunn RT (2002). The Statistician, 51, part 2, 179-187. Van Damme R, Wilson RS, Vahhooydonck B, Aerts P (2002). Nature, 415, 755-756. Woolf A, Ansley L, Bidgood P (2007). J. of Quantitative Analysis in Sports. 3,4,5.

Il decathlon è la specialità più varia dell’atletica e risulta pertanto una disciplina adatta alla costruzione del giovane atleta, ma difficile da definire dal punto di vista tecnico. Gli studi maggiormente diffusi tendono ad indagare le correlazioni tra le varie discipline e a osservarne il peso specifico sul punteggio finale, senza porsi il problema di definire un profilo tecnico ideale dell’atleta. Lo scopo di questo studio pertanto è quello di identificare, tra le 10 discipline del decathlon, quelle che maggiormente influenzano la prestazione, analizzando i primi 100 atleti della lista all-time divisi in quartili e valutare se esistono diverse strategie in base alle singole scuole metodologiche di allenamento per arrivare alla performance finale del decathlon. I risultati mostrano che la performance nel decathlon passa soprattutto nell’eccellenza nelle specialità dei 100m, 110hs, salto in lungo e 400m. Alla luce di questo dovrebbe essere orientato sia il reclutamento del talento che lo sviluppo del relativo programma di allenamento. Anche nel confronto tra le 3 nazioni più competitive nella specialità (USA, Germania e Russia), sono le stesse specialità che giustificano quasi integralmente la differenza di performance.

Background: To understand the technical differences between shot putters of different ages, this study compared biomechanical parameters of the best senior and youth Italian athletes and then to world-class athletes (WC) assessed in previous investigations. Methods: The best throws of 16 shot putters [8 Senior (SG) and 8 Youth (YG)] were recorded by video cameras during the Italian Championships’ final and considered for 3D reconstruction. The following parameters were measured: time of the different throwing phases, shot trajectory, release angle, release velocity, and the force produced in the final phase. Results: Significant differences between SG and YG were detected in second single support time (p = 0.015), support time (p = 0.007), total time (p = 0.028) and in the force produced during the final phase (p < 0.001). A lower level of force, release speed, and a shorter shot trajectory during the double support were detected in SG compared to WC. Conclusions: The present study showed that, although the technical performance of all athletes was similar, some differences exist between YG and SG. The gap between the groups may be partially explained by the difference in force produced in the final phase of the throw and by a different interpretation of the technique.

Bartolomei, S, Nigro, F, Luca, G, Gabriele, S, Ciacci, S, Hoffman, JR, and Merni, F. Acute effects of ammonia inhalants on strength and power performance in trained men. J Strength Cond Res 32(1): 244-247, 2018-The aim of the present study was to investigate the influence of ammonia inhalants on lower body power and maximal isometric strength in trained men. Twenty experienced resistance trained men (age = 26.7 ± 3.7 years; body weight = 80.59 ± 9.0 kg; body height = 179.5 ± 5.7 cm) were tested for counter movement jump power (CMJP), maximal force, and peak rate of force development (pRFD20) expressed during an isometric midthigh pull (IMTP). Assessments were performed using either an ammonia inhalant (AI), a placebo (PL), or no inhalants (N). One-way analysis of variance (ANOVA) with repeated measures was used to compare strength and power performance between the different trials. A significant (p < 0.01) increase in pRFD20 was detected following the use of AI. No significant effects of trial were noted for CMJP and IMTP maximal force (p = 0.251 and p = 0.075, respectively). Results of the present study showed a potential ergogenic effect of AI on rate of force development (i.e., explosive force output), with a trend toward an improvement in maximal force production. The mechanism of action may be related to the stimulatory action of AI often reported by athletes as a "psyching-up" effect. The positive effect of AI on the rate of force development may represent an advantage in sports requiring high rates of force production.

Bartolomei, S, Totti, V, Griggio, F, Malerba, C, Ciacci, S, Semprini, G, and Di Michele, R. Upper-body resistance exercise reduces time to recover after a high-volume bench press protocol in resistance-trained men. J Strength Cond Res 35(2S): S180-S187, 2021-The aim of this study was to compare the effects of active and passive strategies on the recovery response after a high-volume bench press protocol. Twenty-five resistance-trained men (mean ± SD: age = 25.8 ± 3.6 years; body mass = 87.1 ± 12.1 kg; and height = 177.4 ± 4.9 cm) performed a high-volume bench press session (8 sets of 10 reps at 70% of 1 repetition maximum). Subsequently, they were randomly assigned to an active recovery (AR) group (n = 11) or to a passive recovery (PR) group (n = 14). Active recovery consisted of light bench press sessions performed 6 hours and 30 hours after the high-volume exercise protocol. Muscle performance (bench throw power [BTP] and isometric bench press [IBP]) and morphology (muscle thickness of pectoralis major [PECMT] and of triceps brachii [TRMT]) were measured before exercise (baseline [BL]), and at 15-minute (15P), 24-hour (24P), and 48-hour (48P) post-exercise. Post-exercise recovery of both maximal strength and power was accelerated in AR compared with PR. Both BTP and IBP were significantly (p0.001) reduced at 15P and 24P in PR, whereas changes were significant (p0.001) at 15P only in AR. PECMT was still significantly (p = 0.015) altered from BL at 48P in PR, whereas changes were significant (p0.001) at 15P only in AR. No significant interactions (p0.05) between PR and AR were detected for TRMT and muscle soreness. The present results indicate that AR enhances the recovery rate after high-volume exercise sessions and may be included in resistance training programs to optimize muscle adaptations.

The start kinematics has been reported to differ between male and female sprinters. This study aimed to determine whether kinematic differences between the sexes are attributable to an effect of sex per se, or rather to the absolute performance level of the sprinters, quantified by the 100-m time. A total of 20 sprinters (10 M, 10 F), including world-class and elite athletes, were assessed. Start phases from the "set" position to the first two steps were analysed. Linear regression analyses showed a few significant differences between sexes when taking into account the effect of performance level: M had shorter pushing phase duration, higher horizontal velocity at block clearing, and shorter contact times of the first two steps. Conversely, the performance level affected most of the examined parameters: faster sprinters showed the centre of mass (CM) closer to the ground and a more flexed front knee in the "set" position, longer pushing phase duration, lower vertical velocity of the CM at block clearing, and longer contact times and shorter flight times in the first two steps. These findings suggest that the start kinematics is only partially affected by the sex of sprinters, whereas a bigger role is played by their performance level.

Background The aim of this study was to compare the effects of two different training programs oriented to improve vertical jump performance and leg stiffness in basketball players. Methods Fifty-eight male basketball players were involved, divided into three age groups (senior, U19 and U17). Subsequently, within any age group, the players were randomLy divided into two training groups, respectively performing a 16-week "hang-clean" training program (HCL), and a "half-squat" training program (HSQ), lasting for the same duration. HCL was based on the hang clean exercise and included also jump rope training; HSQ was based on the half squat exercise and included also speed ladder training. The squat jump (SJ), the countermovement jump without and with arm swing, and with one step approach (respectively, CMJ, CMJS, and TCMJS) and explosive strength indices obtained with a leg stiffness test were assessed pre- and post-training. Results In senior and U19 athletes both training programs involved an improvement of Vertical Jump performance, with some differences between different age groups. Instead, for the U17 players, only the HSQ led to an enhancement of SJ and TCMJS. Significant enhancement of leg stiffness was observed only in U19 and U17 groups after training. Conclusions The present study showed that the programs based on the hang-clean and half squat allowed to improve explosive strength in basketball training. However, only HSQ was effective for the U17 group. Thus, the present findings demonstrate that specific training programs should be designed according to the age of the players.

Bartolomei, S, Nigro, F, Ruggeri, S, Malagoli Lanzoni, I, Ciacci, S, Merni, F, Sadres, E, Hoffman, JR, and Semprini, G. Comparison between bench press throw and ballistic push-up tests to assess upper-body power in trained individuals. J Strength Cond Res 32(6): 1503-1510, 2018-The purpose of this study was to validate the ballistic push-up (BPU) test performed with hands on a force plate as a method to measure upper-body power. Twenty-eight experienced resistance-trained men (age = 25.4 ± 5.2 years; body mass = 78.5 ± 9.0 kg; body height = 179.6 ± 7.8 cm) performed, 2 days apart, a bench press 1 repetition maximum (1RM) test and upper-body power tests. Mean power (MP) and peak power (PP) were assessed using the bench press throw (BT) test and the BPU test performed in randomized order. The area under the force/power curve (AUC) obtained at BT was also calculated. Power expressed at BPU was estimated using a time-based prediction equation. Mean force and the participant's body weight were used to predict the bench press 1RM. Pearson product-moment correlations were used to examine relationships between the power assessment methods and between the predicted 1RM bench and the actual value. Large correlations (0.79; p < 0.001) were found between AUC and MP expressed at BPU. Large correlations were also detected between MP and PP expressed at BT and BPU (0.75; p < 0.001 and 0.74; p < 0.001, respectively). Very large correlations (0.87; p < 0.001) were found between the 1RM bench and the 1RM predicted by the BPU. Results of this study indicate that BPU represents a valid and reliable method to estimate the upper-body power in resistance-trained individuals.