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PURPOSE: To investigate the relationships between a series of direct and indirect measures of linear and multidirectional speed performance in elite female rugby sevens players. METHODS: Nineteen players from the Brazilian national team performed 40-m linear sprint and 505 change-of-direction (COD) tests on the same day. Based on the linear sprint and COD test performances, the COD deficit (CODD) and deceleration deficit (DD) were also obtained. A Pearson product-moment correlation analysis was used to determine the relationships between linear sprint and COD-derived variables. RESULTS: Linear sprint and 505 COD velocities were not significantly associated (P > .05). Large to very large significant associations (r values ranging from .54 to .78; P < .05) were detected between linear sprint velocity for the different distances tested (10, 15, 30, and 40 m) and CODD. The COD velocity presented a very large inverse significant correlation with CODD and DD (r = -.77 and -.79 respectively; P < .05). A large and significant correlation was identified between CODD and DD (r = .79; P < .05). CONCLUSIONS: Significant associations were observed between linear sprint and CODD, suggesting that faster players are less efficient at changing direction. No relationship was found between sprint velocity and DD, highlighting the independent nature of linear sprints and deceleration capabilities. A comprehensive and detailed analysis of multidirectional speed performance should consider not only linear sprint and COD performances but also complementary COD-derived variables such as the CODD and DD.

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ABSTRACT: Loturco, I, McGuigan, MR, Freitas, TT, Bishop, C, Zabaloy, S, Mercer, VP, Moura, TBMA, Arruda, AFS, Ramos, MS, Pereira, LA, and Pareja-Blanco, F. Half-squat and jump squat exercises performed across a range of loads: differences in mechanical outputs and strength deficits. J Strength Cond Res 37(5): 1052-1056, 2023-The aim of this study was to compare the peak force (PF), peak power (PP), and peak velocity (PV) outputs produced during half-squat (HS) and jump squat (JS) exercises executed at 20, 40, 60, and 80% of 1 repetition maximum (1RM) in the HS (HS 1RM) and to compute and compare the strength deficit (SDef) achieved in these exercises across these loads. Twenty-four national rugby union players (age: 25.7 ± 3.6 years) performed HS 1RM and a progressive loading test in the HS and JS exercises. The PF, PP, and PV values were obtained in all loads for both exercises, and the SDef was calculated as the percentage difference between the PF at distinct relative intensities and the PF at HS 1RM. The differences in HS and JS variables were determined using an analysis of variance with repeated measures. Higher PF, PP, and PV outputs were generated in the JS in comparison with the HS exercise ( p < 0.05); moreover, the SDef magnitudes were significantly lower in the JS ( p < 0.01), for all loading conditions. Importantly, the differences in SDef, and as a consequence, PF, PP, and PV decreased progressively with increasing load. Overall, the loaded JS exhibited increased levels of PF, PP, and PV and reduced levels of SDef when compared to the traditional HS performed across a range of loads. The JS is indicated to reduce the SDef and improve the athletes' ability to apply force at higher velocities. Nevertheless, with heavier loads (i.e., ≥80% HS 1RM), its potential advantages and effectiveness may be seriously compromised.

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ABSTRACT: Loturco, I, Suchomel, T, Kobal, R, Arruda, AFS, Guerriero, A, Pereira, LA, and Pai, CN. Force-velocity relationship in three different variations of prone row exercises. J Strength Cond Res 35(2): 300-309, 2021-This study examined the force-velocity relationship and tested the possibility of determining the relative loading intensity percentage of 1 repetition maximum (%1RM) in 3 different variations of prone row exercises. Thirty male top-level athletes from 2 different sports (National Team rugby union players and professional mixed martial arts fighters) were submitted to maximum dynamic strength assessments in the free prone bench pull, bent-over barbell row, and bent-over Smith machine row, after standard procedures encompassing lifts performed from 40 to 100% of 1RM. The mean velocity, mean propulsive velocity, and peak velocity were measured in all attempts. Linear regression analyses were performed to establish the relationships between the different measures of bar velocities and %1RM. The actual (obtained during the assessments) and predicted 1RM values (based on the predictive equations) for each exercise were compared using a paired t-test. In all exercises, the predicted 1RM scores-based on all velocity variables-were not different from their respective actual values. The close linear relationships between bar velocities and distinct %1RM (coefficient of determination ≥80%, in all experimental conditions) allow precise determination of relative load and maximum dynamic strength, and enable coaches and sports scientists to use the different velocity outputs to rapidly and accurately monitor their athletes on a daily basis.

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This study examined the effect of playing matches against different opponent teams (hard match; HM, medium match; MM, and easy match; EM) on pre-match testosterone concentration (T), pre-to-post match cortisol (C) concentration, and pre-competitive anxiety (CSAI-2 questionnaire) in 20 elite male basketball players. One training session (TS) was also assessed (control condition). Saliva steroids were determined by ELISA. The pre-T concentration was significantly lower for the TS (163±54pmolL-1), compared to the three official matches (EM: 208±82pmolL-1, MM: 213±57pmolL-1, and HM: 218±37pmolL-1) (p<0.05). A significant change in C from pre-to-post was observed for all conditions (TS [5.8±3.7 vs 14.4±9.4ƞmolL-1], EM [10.1±4.9 vs 17.3±10.2ƞmolL-1], MM [13.0±7.4 vs 21.5±8.3ƞmolL-1], and HM [18.9±5.8 vs 31.4±5.3ƞmolL-1] (p<0.05). A higher PRE-C was observed for the HM, compared to TS and EM (p<0.05) and a higher POST-C concentration for the HM was detected, compared to the TS, EM, and MM (p<0.05). A lower anxiety level was observed for the EM (somatic: 15.0±3.7; cognitive: 15.8±4.5 arbitrary units [AU]) compared, to the MM (somatic: 16.4±3.5; cognitive: 17.7±4.0AU) and HM (somatic: 15.8±3.9; cognitive: 18.3±3.9AU) (p<0.05) and a higher self-confidence was observed for the TS (28.9±5.1AU), compared to the HM (26.7±3.0AU) (p<0.05). These results suggest that playing against a high-level opponent may cause a higher psychobiological stress, likely because opponent level may be perceived as threating to the social status in a given hierarchy.

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The purpose of the present study was to examine SIgA responses (concentration [SIgAabs] and a secretion rate [SIgArate]) to official and simulated competitive matches in young soccer players. The sample was composed of 26 male soccer players (age 15.6 ± 1.1 yrs, stature 177.0 ± 6.1 cm, body mass 70.5 ± 5.7 kg). Four soccer matches (two simulated matches [SM] and two official matches [OM]) were conducted. The matches consisted of two halves of 35 min with a 10 min rest interval. Each assessed player participated in only one SM and one OM. All matches were performed in the same week, during the competitive season, and at the same time of the day (9:00 am), separated by 48 h. Saliva samples were collected before and after every match. The session rating of perceived exertion was reported 30 min after each match in order to determine the internal training load (ITL). A significant decrease in SIgAabs and SIgArate after OM was observed when compared to the pre-match value. In addition, the SIgArate was higher at pre-OM when compared to pre-SM. A higher ITL for OM was observed compared to SM. The current findings indicate that OM may lead to a decrease in the main mucosal immunity function parameter of young soccer players that could increase the risk of URTI. Coaches should be aware of it in order to plan appropriate training loads and recovery procedures to avoid or minimize the likelihood of upper respiratory tract infection occurrences.

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This study examined the influence of competition playing venue on the hormonal responses in elite Futsal players. Twenty-one males (age, 19.3 ± 0.7 years; height, 174.2 ± 4.1cm; body mass, 71.8 ± 7.9 kg) from two Futsal teams were monitored during two competitive matches that were played against each other on a home and away basis. Saliva sampling was conducted before (pre) and after (post) each match. The concentration of salivary steroids (testosterone [T] and cortisol [C]) was assessed by ELISA. Resting concentration of salivary steroid (T and C) hormones was not affected by playing venue (home and away). Both Futsal matches promoted a significant increase in T and C from pre--to post-matches (p<0.05), with a higher post-C concentration for playing at home (p<0.05). No effect of playing venue on T was observed. In conclusion, the findings of this study indicate that the playing venue did not elicit a significant change in resting concentration of salivary steroid hormones. However, playing home induced a greater post-match C response, suggesting that the pressure for positive results in front of supporters, families and friends may impose a higher level of stress on the players at their own facility.

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The aim of this study was to investigate salivary T changes and its relationship with power performance over a 1-year competitive season in elite under 15 (U15) and under 17 (U17) soccer players. Soccer players were recruited from 1 soccer club that has been participated in the main state and national leagues for these age groups. The soccer players were divided into 2 age categories (U15, n = 16 and U17, n = 23). A resting saliva sample was taken to determine T level, and power was assessed using the countermovement jump test with a bar of 30% of body mass on the athletes' shoulders on 3 occasions (T1: beginning of the competitive season, T2: end of the regular season, and T3: end of the playoffs). There was a decrease in T concentration at the end of the competitive season (T3) as compared with the beginning of the season (T1) for both age categories (p ≤ 0.05). Conversely, power performance parameters were increased for both age groups (U15: mean power and relative mean power and U17: peak power, mean power, relative peak power, and relative mean power; p ≤ 0.05). No significant correlation was identified between the relative changes in T concentration and power performance in both groups. The findings of this study suggest that T changes and power changes are not related.

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PURPOSE: To analyze the effects of a very congested match schedule on the total distance (TD) covered, high-intensity-running (HIR) distance, and frequency of accelerations and body-load impacts (BLIs) performed in a team of under-15 soccer players (N=10; 15.1±0.2 y, 171.8±4.7 cm, 61±6.0 kg) during an international youth competition. METHODS: Using global positioning systems, player performances were repeatedly monitored in 5 matches performed over 3 successive days. RESULTS: Significant differences were observed between matches (P<.05) for the frequency of accelerations per minute, BLIs, and BLIs per minute. No differences were observed for the TD covered, TD run per minute, number of high-intensity runs, distance covered in HIR, per-minute peak running speed attained, or frequency of accelerations. The frequency of accelerations per minute decreased across the competition while BLIs were higher during the final than in all other matches. CONCLUSIONS: These results suggest that BLIs and acceleration might be used as an alternative means to represent the external load during congested match schedules rather than measures related to running speed or distance covered.

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This study investigated the effect of a 2-week overloading training phase followed by a 2-week tapering phase on internal training load (ITL), salivary cortisol, stress tolerance, and upper respiratory tract infections symptoms (URTI) in 11 male young soccer players (16.0 ± 0.5 yrs). Ratings of perceived exertion (session- RPE) were taken after each training session (N = 194) to determine ITL. Saliva sampling was conducted at the end of each week and cortisol concentration assessed by ELISA. DALDA and WURSS-21 questionnaires were administered every week to evaluate stress tolerance and severity of URTI respectively. The number of athletes reporting URTI symptoms was recorded. The overloading phase promoted greater ITL and a higher resting cortisol concentration than the tapering phase (P < .05). While no significant changes in stress tolerance or URTI severity were observed, the number of athletes reporting URTI symptoms was higher during the overloading phase. A significant correlation was observed between symptoms of stress and severity of URTI (rs=-.71; P = .01). The results indicate that an integrated approach using psychological measures (session-RPE and DALDA), self-reports of URTI symptoms, and endocrine responses (cortisol) to training are pertinent for monitoring young soccer players.

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This study examined the influence of competition playing venue on the hormonal responses, state anxiety and perception of effort in elite basketball players. Eighteen males from two basketball teams were monitored during two competitive matches that were played against each other on a home and away basis. Salivary testosterone (T) and cortisol (C) concentrations were measured before and after each match. The Competitive State Anxiety Inventory-2 (CSAI-2) test was also administrated prior to each match and session ratings of perceived exertion (RPE) were taken post-game. Playing at home was accompanied by elevated pre-match T concentration, as compared to playing away (p<0.05). The matches played at home were also won. Salivary T and C concentrations were similarly elevated across the matches (percent changes from pre to post) played either at home or away. No significant differences in state anxiety and perception of effort were identified between the playing venues. Pre-match T and C concentrations and the percent changes in these hormones were significantly related to somatic anxiety, especially when playing at home (p<0.05). In conclusion, the competition playing venue appeared to influence athlete salivary hormonal responses prior to elite basketball matches. These hormonal responses were associated with player's anxiety state, which might contribute to performance and the eventual match outcomes.

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