Repeated Sprint Ability Test Research Articles

Enxágue bucal com carboidrato não melhora o desempenho em sprints repetidos

1,2 Abstract - The objective of this study was to evaluate the effect of a carbohydrate mouth rinse on the repeated sprint ability (RSA) of young soccer players. Nine youth soccer players (15.0 ± 1.5 years; 60.7 ± 4.84 kg; 1.72 ± 0.05 m; 20.5 ± 1.25 kg/m 2 ) were selected. The athletes were submitted to an RSA test consisting of six sprints of 40 m (going/ return = 20 m + 20 m), separated by 20 s of passive recovery, under three experimental conditions: carbohydrate mouth rinse (CHO) or placebo (PLA) and control (CON). The mouth rinses containing CHO or PLA were administered 5 min and immediately before the beginning of the test in doses of 100 mL. The best sprint time (RSAbest), mean sprint time (RSAmean), and drop-off in sprint performance (fatigue index) were determined for the different treatments. One-way ANOVA for repeated measures did not identify significant differences (P > 0.05) in RSAbest (CHO = 7.30 ± 0.31 s; PLA = 7.30 ± 0.30 s; CON = 7.26 ± 0.16 s), RSAmean (CHO = 7.71 ± 0.30 s; PLA = 7.71 ± 0.25 s; CON = 7.66 ± 0.24 s), or fatigue index (CHO = 5.58 ± 2.16%; PLA = 5.77 ± 3.04%; CON = 5.55 ± 3.72%). The results suggest that a carbohydrate mouth rinse does not improve the repeated sprint performance of young soccer players.

Performance Effects of 6 Weeks of Aerobic Production Training in Junior Elite Soccer Players

This study investigates the performance effects of a 6-week biweekly anaerobic speed endurance production training among junior elite soccer players. Sixteen junior (age 16.9 ± 0.6 years) elite soccer players were tested in the Yo-Yo Intermittent Recovery test level 2 (IR2), 10-m and 35-m sprints, 7 × 35-m repeated-sprint ability (RSA) tests, countermovement jump and squat jump tests, and randomly assigned to either a control group (CG) performing their normal training schedule, which included 4 weekly soccer training sessions of approximately 90 minutes, or a training group performing anaerobic speed endurance production training twice weekly for 6 weeks in addition to their normal weekly schedule. We found that the intervention group significantly improved (p < 0.05) their performance in the Yo-Yo IR2 (63 ± 74 m) and 10-m sprint time (-0.06 ± 0.06 seconds). No significant performance changes were found in the CG. Between-group pretest to posttest differences were found for 10-m sprint times (p < 0.05). No significant changes were observed in the 35-m sprint times, RSA, or jump performances. These results indicate that short-term anaerobic production training is effective in improving acceleration and intermittent exercise performance among well-trained junior elite players.

The Acute Effect of Whole Body Vibration on Repeated Shuttle-Running in Young Soccer Players

The aim of this study was to investigate the acute effects of whole-body vibration (WBV) on Repeated Sprint Ability (RSA). Seventeen male soccer players (16.71±0.47 y) performed three RSA tests (Randomized crossover study design). The second RSA test was done with WBV (RSA2) to assess the effect of WBV. The studied variables were: best time (BT), worst time (WT), total time (TT), the fatigue index (FI) of RSA, and post-test blood lactate (BLa). ANOVA with repeated measures showed no differences between RSA1 and RSA3, while there were significant differences in all variables studied. TT= [RSA2 0.93% and 1.68% lower than RSA1 and RSA3 respectively; p<0.05], BLa= [RSA2 16.97% and 14.73% greater than RSA1 and RSA3 respectively; p<0.001], WT= [RSA2 1.90% and 2.93% lower than RSA1 and RSA3 respectively; p<0.01], and FI = [RSA2 30.64% and 40.15% lower than RSA1 and RSA3 respectively; p<0.0001]. When comparing individual sprints, WBV showed a significant effect at the 5th sprint: RSA2 2.29% and 2.95% lower than RSA1 and RSA3 respectively (p<0.005), while at the 6th sprint: RSA2 2.75% and 4.09% lower than RSA1 and RSA3 respectively; p<0.005. In conclusion, when applying WBV during the recovery periods of Repeated Sprint Ability efforts, most of the performance variables improved.

Validity of a repeated-sprint ability test in young soccer players

This study examined the direct validity of a repeated-sprint ability test (RSAT) in predicting match high-intensity running in young soccer players ( n = 15, 14 years). Players’ RSAT performance (7 × 30 m with < 24 s passive recovery) was assessed 24 h before a competitive match and performance compared with high-intensity activity during a match. Match performance was tracked with GPS technology and heart rate (HR) recorded with short-range telemetry. During the first half, players covered 3526 ± 527 m of which 14.9 ± 4.5% was performed at speed faster than 13 km/h (HIA). The RSA variables were significantly correlated with HIA, match HR and peak speed ( r from 0.59 to 0.82, P < 0.05). This study's findings showed that RSAT was significantly related to match physical and physiological demands in youth soccer. These results support the direct validity of RSAT in predicting match high-intensity running in young soccer players. Le but de cette étude était d’évaluer le caractère prédictif de l’aptitude à répéter les sprints (RSAT) sur les performances physiques en match de jeunes joueurs de football U15 ( n = 15, 14 ans). La performance au RSAT (7 × 30 m séparée par 24 s de récupération passive) a été évaluée 24 heures avant un match officiel. Au cours de cette compétition, les données cinématiques de pic de vitesse, de déplacements à haute intensité (vitesse supérieure à 13,0 km/h, c.-à-d. HIA) et de fréquence cardiaque (FC) ont été enregistrées à l’aide de GPS et par télémétrie. Pendant la première mi-temps, les joueurs ont parcouru 3526 ± 527 m dont 14,9 ± 4,5 % à des vitesses supérieures à 13 km/h. Des relations linéaires significatives entre RSAT et les mesures enregistrées lors du match (pic de vitesse, HIA, valeurs moyennes de FC) ont été observées (valeurs du coefficient de corrélation comprises entre 0,59 à 0,82 ; p < 0,05). Nos résultats ont montré que l’aptitude à répéter les sprints peut être employée chez le jeune joueur de football U15 afin de prédire ses performances physiques en compétition.

Indexes of physical capacity and repeated sprint ability of young soccer players

Repeated sprint ability (RSA) is thought to be an important skill for team sports. However, there is no study that correlates aerobic capacity (AC) and lactic anaerobic capacity (LAC) with RSA in young elite soccer players. Fourteen young players from a professional soccer team underwent two laboratory tests: an incremental exercise test (IET) and an all-out test (AOT) to asses AC and LAC, respectively. Athletes also performed a field RSA test. During both the IET and the AOT tests heart rate, oxygen uptake, carbon dioxide production, and pulmonary ventilation were obtained by a portable gas analyzer. Velocity and fatigue indices were measured during the RSA test. Blood lactate was also measured after the AOT (BLaAOT) and the RSA (BLaRSA) test. No correlation was found between AC and LAC indices and measures of the RSA test, even though the AOT test appeared to fully recruit LAC capacity, as no difference between BLaAOT and BLaRSA was detected. It was concluded that no correlation exists between AC and LAC capacities obtained in the laboratory setting and velocity and fatigue measures from RSA testing. This finding should be taken into account when testing young soccer players.

Postactivation Potentiation on Repeated-Sprint Ability in Elite Handball Players

The aim of this study was to analyze the changes on repeated-sprint ability (RSA) performance after heavy load exercise in elite handball players. Twelve subjects were submitted to the following experimental sessions: (a) 1-repetition maximum (1RM) test on the half squat exercise, (b) RSA test (control condition), and (c) RSA with a conditioning activity on the same exercise as 1RM test (experimental condition). The conditioning activity comprised 1 set of 5 × 50% 1RM, 1 set of 3 × 70% 1RM, and 5 sets of 1 × 90% 1RM. A significant improvement in the best sprint time (RSAbest) and mean sprint time (RSAmean) was observed with the conditioning activity (RSAbest = 5.74 ± 0.16 seconds; RSAmean = 5.99 ± 0.19 seconds) when compared with the situation without the conditioning activity (RSAbest = 5.82 ± 0.15 seconds; RSAmean = 6.06 ± 0.18 seconds; p < 0.01) with a moderate (Cohen's d = -0.54) and small effect (Cohen's d = -0.41) to RSAbest and RSAmean, respectively. Therefore, the findings of this study demonstrated that prior heavy load exercise can be used to improve the RSA performance, however, with a small to moderate magnitude of change.

Significant Molecular and Systemic Adaptations after Repeated Sprint Training in Hypoxia

While intermittent hypoxic training (IHT) has been reported to evoke cellular responses via hypoxia inducible factors (HIFs) but without substantial performance benefits in endurance athletes, we hypothesized that repeated sprint training in hypoxia could enhance repeated sprint ability (RSA) performed in normoxia via improved glycolysis and O2 utilization. 40 trained subjects completed 8 cycling repeated sprint sessions in hypoxia (RSH, 3000 m) or normoxia (RSN, 485 m). Before (Pre-) and after (Post-) training, muscular levels of selected mRNAs were analyzed from resting muscle biopsies and RSA tested until exhaustion (10-s sprint, work-to-rest ratio 1∶2) with muscle perfusion assessed by near-infrared spectroscopy. From Pre- to Post-, the average power output of all sprints in RSA was increased (p<0.01) to the same extent (6% vs 7%, NS) in RSH and in RSN but the number of sprints to exhaustion was increased in RSH (9.4±4.8 vs. 13.0±6.2 sprints, p<0.01) but not in RSN (9.3±4.2 vs. 8.9±3.5). mRNA concentrations of HIF-1α (+55%), carbonic anhydrase III (+35%) and monocarboxylate transporter-4 (+20%) were augmented (p<0.05) whereas mitochondrial transcription factor A (−40%), peroxisome proliferator-activated receptor gamma coactivator 1α (−23%) and monocarboxylate transporter-1 (−36%) were decreased (p<0.01) in RSH only. Besides, the changes in total hemoglobin variations (Δ[tHb]) during sprints throughout RSA test increased to a greater extent (p<0.01) in RSH. Our findings show larger improvement in repeated sprint performance in RSH than in RSN with significant molecular adaptations and larger blood perfusion variations in active muscles.

Effect of carbohydrate mouth rinsing on multiple sprint performance

BackgroundResearch suggests that carbohydrate mouth rinsing (CMR) improves endurance performance; yet, little is known regarding the effect of CMR on multiple sprint efforts. As many sports involve multiple sprinting efforts, followed by periods of recovery, the aim of our current study was to investigate the influence of CMR on multiple sprint performance.MethodsWe recruited eight active males (Age; 22 ± 1 y; 75.0 ± 8.8 kg; estimated VO2max 52.0 ± 3.0 ml/kg/min) to participate in a randomly assigned, double-blind, counterbalanced study administering a CMR (6.4% Maltodextrin) or similarly flavoured placebo solution. Primary outcomes for our study included: (a) time for three repeated sprint ability tests (RSA) and (b) the Loughborough Intermittent Shuttle Test (LIST). Time was expressed in seconds (sec). Secondary outcomes included ratings of perceived exertion (RPE) and blood glucose concentration. Tertiary outcomes included two psychological assessments designed to determine perceived activation (i.e., arousal) and pleasure-displeasure after each section of the LIST. We analysed our data using a two-way analysis of variance (ANOVA) for repeated measures, a Bonferroni adjusted post hoc t-test to determine significant differences in treatment, and a liberal 90% confidence interval between treatment conditions. Effect sizes were calculated between trials and interpreted as ≤ 0.2 trivial, > 0.2 small, > 0.6 moderate, > 1.2 large, > 2 very large and > 4 extremely large. Data are means ± SD. Overall statistical significance was set as P < 0.05; yet, modified accordingly when Bonferroni adjustments were made.ResultsOverall, we observed no significant difference in average (3.46 ± 0.2 vs. 3.44 ± 0.17; P = 0.11) or fastest time (3.38 ± 0.2 vs. 3.37 ± 0.2; P = 0.39) in the RSA test for the placebo vs. CMR conditions, respectively. Similar findings were also noted for the placebo vs. CMR, respectively, during the LIST test (3.52 ± 0.2 vs. 3.54 ± 0.2 sec; P = 0.63). Despite a significantly higher within group RPE during the 3rd and 4th sections of the LIST (< 0.05), no between group differences were otherwise noted. No differences were noted for blood glucose concentrations throughout the testing protocol. Lastly, from a psychological perspective, we observed no differences in pleasure-displeasure or perceived activation.ConclusionsThe results of our current study suggest that CMR does not improve exercise performance, RPE or perceived pleasure-displeasure during high intensity activity requiring repeated, intermittent, sprint efforts.

Seasonal Changes in Physical Performance and Heart Rate Variability in High Level Futsal Players

The aim of this study was to determine the changes in physical performance and resting heart rate variability (HRV) in professional futsal players during the pre-season and in-season training periods. 11 athletes took part in the study (age=24.3±2.9 years; height=176.3±5.2 cm; weight=76.1±6.3 kg), and performed a repeated-sprint ability (RSA) test [6×40 m (20+20 m with a 180° change of direction) sprints separated by 20 s of passive recovery] and Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) at 3 different moments (M1=beginning of pre-season; M2=end of pre-season; M3=mid in-season). The HRV indices were assessed at the same moments. After the short pre-season (3-week), mean RSA time (RSAmean) (M1=7.43±0.2 s; M2=7.24±0.2 s; P=0.003), decrement in RSA performance (RSAdecrement) (M1=6.7±0.3%; M2=5.0±0.9%; P=0.001), and Yo-Yo IR1 distance (M1=1.244±298 m; M2=1.491±396 m; P=0.002) were significantly improved (P<0.05). During the in-season (i. e., M3), performance in Yo-Yo IR1 and RSAmean were maintained. In contrast, RSAbest (M2=6.89±0.2 to M3=6.69±0.3; P=0.001) was improved and RSAdecrement (M2=5.0±0.9% to M3=6.6±0.9%; P=0.001) was impaired. At M2, there was an increase in HRV vagal-related indices compared with M1 that was maintained at M3. In conclusion, after a short pre-season, futsal players improved their RSA and Yo-Yo IR1 performance with concomitant improvements in HRV. These indices were maintained during the in-season period while RSAbest was improved and RSAdecrement impaired. Frequent monitoring of these performances and HRV indices may assist with identification of individual training adaptations and/or early signs of maladaption.

Effects of Ramadan on the Diurnal Variations of Repeated-Sprint Performance

This study examined the effects of Ramadan on cycling repeated-sprint ability (RSA) and corresponding diurnal variations. Twelve active men performed an RSA test (5 × 6-s maximal sprints interspersed with 24 s passive recovery) during morning and afternoon sessions 1 wk before Ramadan (BR), during the second (R2) and the fourth (R4) weeks of Ramadan, and 2 wk after Ramadan (AR). Maximal voluntary contraction was assessed before (MVCpre), immediately after (MVCpost), and 5 min after the RSA test (MVCpost5). Moreover, hematocrit, hemoglobin, and plasma sodium and potassium (K+) concentrations were measured at rest and after the RSA test and MVCpost. Overall, peak power (Ppeak) during the RSA test decreased throughout the 5 sprints. Ppeak measured in the first sprint and MVCpre were lower during Ramadan than BR in the afternoon (P < .05) and higher in the afternoon than the morning BR and AR (P < .05). However, this diurnal rhythmicity was not found for the last 4 sprints' Ppeak, MVCpost, and MVCpost5 in all testing periods. Furthermore, the last 4 sprints' Ppeak, MVCpost, MVCpost5, and morning MVCpre were not affected by Ramadan. [K+] measured at rest and after the RSA test and MVCpost were higher during Ramadan than BR in the afternoon (P < .05) and higher in the afternoon than the morning during Ramadan (P < .05). Fatigability is higher in the afternoon during Ramadan, and, therefore, training and competition should be scheduled at the time of day when physical performance is less affected.

Diurnal Variations in Physical Performances Related to Football in Young Soccer Players

This study investigated the effects of time-of-day on aerobic and anaerobic performances during the Yo-Yo, repeated sprint ability (RSA) and the Wingate tests in young soccer players. In a counterbalanced and a random order, twenty junior male soccer players completed the Yo-Yo, the RSA, and the Wingate tests at two different times-of-day: 07:00 and 17:00 h. During the Yo-Yo test, the total distance (TD) covered and the estimated maximal aerobic velocity (MAV) were determined. The peak power (PP) during each sprint, the percentage of decrement of PP (PD) and total work (Wtotal) during the RSA test were, also, measured. In addition, during the Wingate test, the peak (P(peak)) and mean (P(mean)) powers were recorded. During the Wingate test, P(peak) and P(mean) were significantly higher at 17:00 than 07:00 h (P<0.05) with diurnal gains of 3.1±3.6 and 2.9±3.5% respectively. During the RSA test, PP during the first two sprints, Pdec and Wtotal were, also, higher in the evening (P<0.05) with amplitudes of 4.8±4.6, 3.1±3.0, 13.1±32.1, and 4.1±2.5% respectively. Likewise, TD and MAV during the Yo-Yo test were higher at 17:00 than 07:00 h with diurnal gains of 13.1±10.7 and 4.2±3.3 respectively. The present study confirms the daily variations of both aerobic and anaerobic performances during the Yo-Yo, the RSA, and the Wingate tests in trained young Tunisian soccer players.

Repeated-Sprint and Change-of-Direction Abilities in Physically Active Individuals and Soccer Players

The relationship between repeated-sprint ability (RSA) and repeated change-of-direction (RCOD) matched on intervals and distances was investigated in this study. The discrimination abilities of the tests were also examined. Using a within-subject repeated measures design, 25 physically active individuals (ACTs), 16 college soccer players (COL), and 18 professional soccer players (PRO) performed the RSA and RCOD tests during which the fastest time (FT), average time (AT), total time (TT), and percentage decrement score (%Dec) were recorded. We concluded that RSA and RCOD tested separate motor abilities because the shared variance between them in the FT, AT, and TT was ≤50%. Both RSA and RCOD tests were reliable (intraclass correlation coefficient ranged 0.79-0.90) and valid performance assessments in terms of construct in that they discriminated between ACT and soccer players (irrespective of the soccer skill level in this study). Specifically, the FT, AT, and TT (but not %Dec) of RSA and RCOD were significantly higher in ACT as compared with that in both COL and PRO (p < 0.05). Most values of the RSA/RCOD index in COL and PRO were 0.59, which were significantly higher than those of ACT (0.53, p < 0.05). We proposed the use of the RSA/RCOD index with a target value of 0.59 to prioritize and quantify the training needs of RSA and RCOD for soccer players.

Repeated-Sprint Ability: Where Are We?

Repeated-sprint ability (RSA) is now well accepted as an important fitness component in team-sport performance. It is broadly described as the ability to perform repeated short (~3-4 s, 20-30 m) sprints with only brief (~10-30 s) recovery between bouts. Over the past 25 y a plethora of RSA tests have been trialed and reported in the literature. These range from a single set of ~6-10 short sprints, departing every 20-30 s, to team-sport game simulations involving repeating cycles of walk-jog-stride-sprint movements over 45-90 min. Such a wide range of RSA tests has not assisted the synthesis of research findings in this area, and questions remain regarding the optimal methods of training to best improve RSA. In addition, how RSA test scores relate to player "work rate," match performance, or both requires further investigation to improve the application of RSA testing and training to elite team-sport athletes.

Time of Day Effects on Repeated Sprint Ability

The present study aimed at investigating the effects of time-of-day on muscle power and associated electromyographic (EMG) activity level of 4 thigh muscles during a repeated pedalling sprint exercise. After a familiarization session, 12 male subjects were asked to perform the repeated sprint ability test during 2 experimental sessions (randomized order), which were set up either at 06:00 or 18:00 h. For each sprint, peak power output, percentage of peak power decrement and total work were calculated. EMG activity of vastus lateralis, rectus femoris, vastus medialis and biceps femoris muscles was recorded throughout the test and analyzed for each sprint. Total work and percentage of peak power decrement were higher in the evening than in the morning (p<0.01 and p<0.05, respectively). Likewise, peak power was significantly higher at 18:00 than 06:00 h during the first 3 sprints (p<0.01 for sprint 1 and p<0.05 for sprint 2 and 3). There was no time-of-day effect for EMG activity level. The neuromuscular efficiency decreased significantly over the repeated sprint ability test at the 2 times of testing (p<0.01). Despite diurnal fluctuation in muscular power and neuromuscular fatigue during the repeated sprint ability test, EMG activity of major thigh muscles was not time-of-day dependent.

The effect of an official match on repeated sprint ability in junior basketball players

The aim of this study was to investigate the effect of an official basketball match on repeated sprint ability indices in male junior players. Ten (16 ± 1 years old; 183.6 ± 7.0 cm; 76.6 ± 8.0 kg) starting players for their teams performed three repeated sprint ability tests, before, at half-time and immediately after an official match. Each repeated sprint ability test consisted of 10 shuttle-run sprints of 30 m (15 + 15 m) separated by 30 seconds of passive recovery. The matches were video-taped to determine the frequency of eight types of movement patterns, and blood lactate concentration was measured before and immediately after each repeated sprint ability test. Differences in total time, ideal time and percentage decrement between tests was assessed by a one-way analysis of variance (ANOVA) with repeated measures, while a two-way ANOVA with repeated measures was used to identify differences in blood lactate concentration. The main results indicated a significant decrease in total movement frequency (−9.9%), high-intensity activity frequency (−13.3%), run frequency (−13.0%) and sprint frequency (−23.3%) in the second compared to the first half, and significantly worse total time and ideal time at the end of the match, compared to the start and half-time (differences ranging from −2.1% to -2.9%, P < 0.05). The practical implications of these findings suggest that regional basketball players should participate in conditioning sessions that focus on the improvement of repeated sprint ability.

The effect of Ramadan fasting on the diurnal variations in aerobic and anaerobic performances in Tunisian youth soccer players

The purpose of this investigation was to assess the effects of Ramadan fasting on physical performance in youth Muslim athletes their diurnal fluctuations. In a balanced and randomized study design, 10 Tunisian junior male soccer players completed the Yo-Yo intermittent recovery test level 1 (YYIRT) and the repeated sprint ability (RSA) at 07:00 and 17:00 h on three different occasions: 1 week before Ramadan (BR), the second week of Ramadan (SWR) and the fourth week of Ramadan (ER). There was an interval of 36 h between any two successive tests. Oral temperature was measured before each test. Under each condition, the results showed a time-of-day effect on oral temperature. However, no significant diurnal variations in rate of perceived exertion (RPE) scores were observed during the three periods (BR, SWR and ER). Performances during the YYIRT and the first two sprints of the RSA improved significantly from morning to evening during BR. However, daily fluctuations disappeared during the SWR and ER. Considering the effect of Ramadan on physical performances, in comparison with BR, no significant difference was observed during Ramadan at 07:00 h. However, the variables were significantly lower in SWR and ER at 17:00 h. The RPE scores were higher during SWR and ER in the evening after the YYIRT and RSA tests. In conclusion, the time-of-day effects on physical performances variables tend to disappear during Ramadan. In comparison with the period BR, physical performances were unaffected at 07:00 h but impaired at 17:00 h during Ramadan.

The Effect of a Combined High-Intensity Plyometric and Speed Training Program on the Running and Jumping Ability of Male Handball Players

The aim of this study was to investigate the effect of a combined program including sprint repetitions and drop jump training in the same session on male handball players. Twenty-two male handball players aged more than 20 years were assigned into 2 groups: experimental group (n=11) and control group (n=11). Selection was based on variables "axis" and "lines", goalkeepers were not included. The experimental group was subjected to 2 testing periods (test and retest) separated by 12 weeks of an additional combined plyometric and running speed training program. The control group performed the usual handball training. The testing period comprised, at the first day, a medical checking, anthropometric measurements and an incremental exercise test called yo-yo intermittent recovery test. 2 days later, participants performed the Repeated Sprint Ability test (RSA), and performed the Jumping Performance using 3 different events: Squat jump (SJ), Countermovement jump without (CMJ) and with arms (CMJA), and Drop jump (DJ). At the end of the training period, participants performed again the repeated sprint ability test, and the jumping performance. The conventional combined program improved the explosive force ability of handball players in CMJ (P=0.01), CMJA (P=0.01) and DJR (P=0.03). The change was 2.78, 2.42 and 2.62% respectively. No significant changes were noted in performances of the experimental group at the squat jump test and the drop jump with the left leg test. The training intervention also improved the running speed ability of the experimental group (P=0.003). No statistical differences were observed between lines or axes. Additional combined training program between sprint repetition and vertical jump in the same training session positively influence the jumping ability and the sprint ability of handball players.

Analysis of repeated high-intensity running performance in professional soccer

The aims of this study were twofold: (1) to characterize repeated high-intensity movement activity profiles of a professional soccer team in official match-play; and (2) to inform and verify the construct validity of tests commonly used to determine repeated-sprint ability in soccer by investigating the relationship between the results from a test of repeated-sprint ability and repeated high-intensity performance in competition. High-intensity running performance (movement at velocities >19.8 km · h−1 for a minimum of 1 s duration) was measured in 20 players using computerized time–motion analysis. Performance in 80 French League 1 matches was analysed. In addition, 12 of the 20 players performed a repeated-sprint test on a non-motorized treadmill consisting of six consecutive 6 s sprints separated by 20 s passive recovery intervals. In all players, most consecutive high-intensity actions in competition were performed after recovery durations ≥61 s, recovery activity separating these efforts was generally active in nature with the major part of this spent walking, and players performed 1.1 ± 1.1 repeated high-intensity bouts (a minimum of three consecutive high-intensity bouts with a mean recovery time ≤20 s separating efforts) per game. Players reporting lowest performance decrements in the repeated-sprint ability test performed more high-intensity actions interspersed by short recovery times (≤20 s, P < 0.01 and ≤30 s, P < 0.05) compared with those with higher decrements. Across positional roles, central-midfielders performed more high-intensity actions separated by short recovery times (≤20 s) and spent a larger proportion of time running at higher intensities during recovery periods, while fullbacks performed the most repeated high-intensity bouts (statistical differences across positional roles from P < 0.05 to P < 0.001). These findings have implications for repeated high-intensity testing and physical conditioning regimens.

Whole-body vibration as a method of recovery for soccer players

The aim of this study was to determine whether superimposed whole-body vibration could improve the recovery-related effects of a traditional cool-down in high-level soccer players. Sixteen high-level junior soccer players performed a repeated-sprint ability test, after which they performed a traditional cool-down, with (experimental group) or without (control group) superimposed whole-body vibration. Functional recovery was measured through vertical jump height and maximal voluntary isometric force in leg-extension. The repeated-sprint ability test induced increases (from 161 to 215%; P<0.05) in muscle pain measured by visual analogue scale in the control group only. Vertical jump height was recovered earlier with than without whole-body vibration (24 h after the repeated-sprint ability test; P<0.05). The results of this study demonstrate that whole-body vibration in combination with a traditional cool-down can reduce perceived muscle pain and enhance recovery after a soccer-specific exercise.

Validity and reliability of a new field test (Carminatti's test) for soccer players compared with laboratory-based measures

The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test–retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h−1 was increased by 1.2 km · h−1 every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO2max (v-VO2max). Peak running velocity in Carminatti's test was strongly correlated with v-VO2max (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = −0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.