Yo-Yo Test Research Articles

Assessing Shortened Field-Based Heart-Rate-Variability-Data Acquisition in Team-Sport Athletes.

To compare the LnRMSSD and the LnRMSSD:RR values obtained during a 5-min stabilization period with the subsequent 5-min criterion period and to determine the time course for LnRMSSD and LnRMSSD:RR stabilization at 1-min analysis in elite team-sport athletes. 35 elite futsal players (23.9 ± 4.5 y, 174.2 ± 4.0 cm, 74.0 ± 7.5 kg, 1576.2 ± 396.3 m in the Yo-Yo test level 1). The RR-interval recordings were obtained using a portable heart-rate monitor continuously for 10 min in the seated position. The 2 dependent variables analyzed were LnRMSSD and LnRMSSD:RR. To calculate the magnitude of the differences between time periods, effect-size (ES) analysis was conducted. To assess the levels of agreement, intraclass correlation coefficients (ICC) and Bland-Altman plots were used. The LnRMSSD and LnRMSSD:RR values obtained during the stabilization period (0-5 min) presented very large to nearly perfect ICCs with the values obtained during the criterion period (5-10 min), with trivial ESs. In the ultra-short-term analysis (ie, 1-min segments) the data showed slightly less accurate results, but only trivial to small differences with very large to nearly perfect ICCs were found. LnRMSSD and LnRMSSD:RR can be recorded in 5 min without traditional stabilization periods under resting conditions in team-sport athletes. The ultra-short-term analysis (1 min) also revealed acceptable levels of agreement with the criterion.

Seasonal Variation In Physical Fitness Performance And Its Comparison Regarding Age Of Soccer Players

Speed, power, agility, endurance and body composition (BC) parameters are important components of fitness performance (FP) and determine the level of success in soccer. FP is not stable in time as is influenced by several factors: period within the annual training cycle, player’s ontogenesis, efficiency of the training process, player’s health state and other. PURPOSE: To find out differences in speed, power, agility, endurance and BC in elite youth soccer players at the beginning and end of the season depending on the age category. METHODS: The elite players of 2 age groups (U21=24 and U18=21) of the highest league participated in fitness tests at the beginning (PRE) and end (POST) of the season. FP was assessed using the following tests: treadmill VO2max test (VO2max), YoYo test (YoYoIRT1), BC ratio of extra- and intracellular mass (ECM/BCM), power jump test: countermovement jump with free arms (CMJFA), countermovement jump (CMJ), squat jump (SJ), linear running speed at 5 m (S5), 10 m (S10) and flying 20 m sprint (F20), agility K-test, repeated agility ability (RAA). FP differences regarding age and time were examined using mixed model of MANOVA. RESULTS: MANOVA showed a significant effect of both main factors on FP (Age: F11,76=3.28; p<.01, η2=0.32, Time: F11,76=2.53; p<0.05, η2=0.25). The time had a significant effect on FP in following indicators: YoYoIRT1 (F1,43=43.43; p<0.01, η2=0.50), ECM/BCM (F1,43=8.23; p<0.01, η2=0.16), CMJFA (F1,43=4.35; p<0.05, η2=.09), CMJ (F1,43=6.66; p<.05, η2=0.13), SJ (F1,43=12.16; p<0.01, η2=0.22), S10 (F1,43=4.83; p<0.05, η2=0.10), F20 (F1,43=46.72; p<0.01, η2=0.52), K-test (F1,43=14.04; p<0.01, η2=0.25) and RAA (F1,43=7.04; p<0.05, η2=0.14). No significant changes were detected in VO2max and S5 (p>0.05). Between group effects of FP was significant in all tests except to S10 sprint. The highest improvement was in YoYoIRT1 (U21: PRE 2053.22±322.96 m vs. POST 2233.33±331.24 m, t23 = -3.70, p<0.01; U19: PRE 1683.81±393.94 m vs. POST 2085.71±389.93m, t20 = -5.27, p<0.01). CONCLUSION: The level of FP was the higher at the end of the competitive season. The level of endurance detected in both laboratory and field conditions revealed different values. Age appeared to have a significant effect when comparing the selected FP parameters. Supported by PRVOUK P38

Relationships between the yo-yo intermittent recovery test and anaerobic performance tests in adolescent handball players.

The aim of the present study was to investigate relationships between a performance index derived from the Yo-Yo Intermittent Recovery Test level 1 (Yo-Yo IR1) and other measures of physical performance and skill in handball players. The other measures considered included peak muscular power of the lower limbs (Wpeak), jumping ability (squat and counter-movement jumps (SJ, CMJ), a handball skill test and the average sprinting velocities over the first step (VS) and the first 5 m (V5m). Test scores for 25 male national-level adolescent players (age: 17.2 ± 0.7 years) averaged 4.83 ± 0.34 m·s−1 (maximal velocity reached at the Yo-Yo IR1); 917 ± 105 Watt, 12.7 ± 3 W·kg−1 (Wpeak); 3.41 ± 0.5 m·s−1 and 6.03 ± 0.6 m·s−1 (sprint velocities for Vs and V5m respectively) and 10.3 ± 1 s (handball skill test). Yo-Yo IR1 test scores showed statistically significant correlations with all of the variables examined: Wpeak (W and W·kg−1) r = 0.80 and 0.65, respectively, p≤0.001); sprinting velocities (r = 0.73 and 0.71 for VS and V5m respectively; p≤0.001); jumping performance (SJ: r = 0.60, p≤0.001; CMJ: r= 0.66, p≤0.001) and the handball skill test (r = 0.71; p≤0.001). We concluded that the Yo-Yo test score showed a sufficient correlation with other potential means of assessing handball players, and that intra-individual changes of Yo-Yo IR1 score could provide a useful composite index of the response to training or rehabilitation, although correlations lack sufficient precision to help in players’ selection.

Efektivitas minuman kombinasi maltodekstrin dan vitamin C terhadap hitung jenis leukosit pada atlet sepak bola

Backgrounds: The immune system changing affects the fitness. Exercise induces the immune responses, oxidative stress and tissue damage that alters leukocyte counts. Maltodextrin supplies higher energy reserves, that can improve the immune system profiles. Vitamin C as an antioxidant against tissue damage.Objective: This study aims to assess the effectiveness of a maltodextrin and vitamin C combination drink on leukocyte differential count after exercise.Method: This study was quasi-experimental with the within-subject design. Subjects were 14 collegiate football players of the State University of Yogyakarta and fulfilled the inclusion and exclusion criteria. Subjects were selected with a purposive sampling. Subjects received a combination of 15% maltodextrin and 250 mg of vitamin C beverage, 300 mL. Subjects did wash out for 6 days, then received placebo beverage (300 mL plain water). Subjects drank 30 minutes before and 5 minutes after physical exercise. Exercise loads were yoyo intermittent test and run gradually until 80 HRmaks. Blood samples were taken immediately and 30 minutes after exercise.Results: In the administration of intervention beverage, immediately to 30 minutes after exercise neutrophils increased (p=0,006); lymphocytes decreased (p=0.015); monocytes decreased (p=0.000); and eosinophils decreased (p=0.613). In the administration of placebo beverage, immediately to 30 minutes after exercise, neutrophils increased (p=0.359); lymphocytes decreased (p=0.257); monocytes decreased (p=0.146); and eosinophils increased (p=0.549). Neutrophils (p=0.003) and monocyte (p=0.003) had significant difference between both administration drink at 30 minutes after exercise. Lymphocyte and monocyte significantly decrease (p&lt;0.05) at intervention than placebo.Conclusion: Maltodextrin and vitamin C combination drink effect on the decreasing of lymphocyte and monocyte 30 minutes after exercise.

The Yo-Yo IE2 test: physiological response for untrained men versus trained soccer players.

This study aimed to examine the physical capacity and physiological response to the Yo-Yo Intermittent Endurance level 2 test (IE2) for untrained individuals (UTR) and trained male soccer players (TR) and to investigate the determinants of intense intermittent exercise performance. Thirty-four healthy UTR males and 15 age-matched TR performed a maximal incremental treadmill test and a Yo-Yo IE2 test. Muscle biopsies and blood samples were obtained, and heart rate (HR) was measured before, during, and after tests. UTR had a 67% lower (P < 0.01) Yo-Yo IE2 performance (665 ± 271 vs 2027 ± 298 m; effect size (ES), 4.8), 34% lower V˙O2max (P < 0.01), and 19% lower resting muscle glycogen (P < 0.05) than those of TR. Blood lactate concentration and HR during the first 560 m of the Yo-Yo IE2 test were higher (P < 0.01) in UTR than those in TR (560 m, 7.4 ± 2.8 vs 2.4 ± 0.8 mM; ES, 1.7-2.8; 188 ± 11 vs 173 ± 8 bpm; ES, 0.9-1.5), with no differences at exhaustion. Time >95% HRmax was lower (P < 0.01) in UTR than that in TR (1.0 ± 1.1 vs 6.3 ± 2.9 min; ES, 3.1). Mean rates of muscle creatine phosphate utilization (16.5 ± 9.5 vs 4.3 ± 2.7 mmol·kg d.w·min), muscle lactate accumulation (16.8 ± 9.1 vs 4.2 ± 2.9 mmol·kg d.w.·min), and glycogen breakdown (29.6 ± 14.2 vs 7.7 ± 5.4 mmol·kg d.w.·min) were fourfold higher (P < 0.01; ES, 1.4-1.7) in UTR than those in TR. For UTR, correlations (P < 0.01) were observed between Yo-Yo IE2 performance and V˙O2max (r = 0.77), incremental treadmill test performance (r = 0.79), and muscle citrate synthase activity (r = 0.57) but not for TR (r = -0.12 to 0.50; P > 0.05). The Yo-Yo IE2 test was shown to possess high construct validity by showing large differences in performance, HR, and anaerobic metabolism between UTR and TR. In addition, V˙O2max seemed to be important for intermittent exercise performance in UTR but not for TR.

Sensitivity of the Yo-Yo Intermittent Recovery Test and cardiac autonomic responses to training in futsal players.

This study examined the sensitivity of maximal (Yo-Yo Intermittent Recovery [IR] 1 and 2) and submaximal (5'-5') tests to identify training adaptations in futsal players along with the suitability of heart-rate (HR) and HR-variability (HRV) measures to identify these adaptations. Eleven male professional futsal players were assessed before (pretraining) and after (posttraining) a 5-wk period. Assessments included 5'-5' and Yo-Yo IR1 and IR2 performances and HR and HRV at rest and during the IR and 5'-5' tests. Magnitude-based-inference analyses examined the differences between pre- and posttraining, while relationships between changes in variables were determined via correlation. Posttraining, Yo-Yo IR1 performance likely increased while Yo-Yo IR2 performance almost certainly increased. Submaximal HR during the Yo-Yo IR1 and Yo-Yo IR2 almost certainly and likely, respectively, decreased with training. HR during the 5'-5' was very likely decreased, while HRV at rest and during the 5'-5' was likely increased after training. Changes in both Yo-Yo IR performances were negatively correlated with changes in HR during the Yo-Yo IR1 test and positively correlated with the change in HRV during the 5'-5'. The current study has identified the Yo-Yo IR2 as more responsive for monitoring training-induced changes of futsal players than the Yo-Yo IR1. Changes in submaximal HR during the Yo-Yo IR and HRV during the 5'-5' were highly sensitive to changes in maximal performance and are recommended for monitoring training. The 5'-5' was recommended as a time-efficient method to assess training adaptations for futsal players.

Concurrent speed endurance and resistance training improves performance, running economy, and muscle NHE1 in moderately trained runners.

The purpose of this study was to examine whether speed endurance training (SET, repeated 30-s sprints) and heavy resistance training (HRT, 80-90% of 1 repetition maximum) performed in succession are compatible and lead to performance improvements in moderately trained endurance runners. For an 8-wk intervention period (INT) 23 male runners [maximum oxygen uptake (V̇O(2max)) 59 ± 1 ml·min(-1)·kg(-1); values are means ± SE] either maintained their training (CON, n = 11) or performed high-intensity concurrent training (HICT, n = 12) consisting of two weekly sessions of SET followed by HRT and two weekly sessions of aerobic training with an average reduction in running distance of 42%. After 4 wk of HICT, performance was improved (P < 0.05) in a 10-km run (42:30 ± 1:07 vs. 44:11 ± 1:08 min:s) with no further improvement during the last 4 wk. Performance in a 1,500-m run (5:10 ± 0:05 vs. 5:27 ± 0:08 min:s) and in the Yo-Yo IR2 test (706 ± 97 vs. 491 ± 65 m) improved (P < 0.001) only following 8 wk of INT. In HICT, running economy (189 ± 4 vs. 195 ± 4 ml·kg(-1)·km(-1)), muscle content of NHE1 (35%) and dynamic muscle strength was augmented (P < 0.01) after compared with before INT, whereas V̇O(2max), muscle morphology, capillarization, content of muscle Na(+)/K(+) pump subunits, and MCT4 were unaltered. No changes were observed in CON. The present study demonstrates that SET and HRT, when performed in succession, lead to improvements in both short- and long-term running performance together with improved running economy as well as increased dynamic muscle strength and capacity for muscular H(+) transport in moderately trained endurance runners.

Relationships Between Field Performance Tests in High-Level Soccer Players

To reduce athlete testing time, the aim of this study was to investigate the relationship between the Yo-Yo intermittent recovery test levels 1 (IR1) and 2 (IR2) performances, maximal sprinting speed (10, 20, and 35 m), repeated sprint ability (RSA; 7 × 35 m), and submaximal heart rates (HRs) after 2 and 4 minutes of the Yo-Yo IR tests by testing 57 high-level soccer players. All players played regularly in one of 3 highest levels of Norwegian soccer and were tested during 3 sessions on 3 consecutive days. Large correlations were observed between Yo-Yo IR1 and IR2 test performances (r = 0.753, p ≤ 0.05). Small and moderate correlations were found between 20- and 35-m sprinting speed and Yo-Yo IR1 performance (r = -0.289 and -0.321, respectively, p ≤ 0.05), whereas 35-m sprinting speed correlated moderately to Yo-Yo IR2 performance (r = -0.371, p ≤ 0.05). Repeated sprint ability at 10, 20, and 35 m all showed moderate to large correlations to Yo-Yo IR1 performance (r = -0.337 to -0.573, p ≤ 0.05). Repeated sprint ability at 20 m (r = -0.348, p ≤ 0.05) and 35 m (r = -0.552, p ≤ 0.01) correlated moderately and largely to Yo-Yo IR2 performance. In addition, moderate and large correlations were found between submaximal Yo-Yo IR1 HRs after 2 (r = -0.483, p ≤ 0.01) and 4 minutes (r = -0.655, p ≤ 0.01) and Yo-Yo IR1 performance, and 2 minutes Yo-Yo IR2 HR and Yo-Yo IR2 performance (r = -0.530, p ≤ 0.01). Intraclass correlation measures of submaximal HR after 2 and 4 minutes of Yo-Yo IR1 test and after 2 minutes of the Yo-Yo IR2 were 0.92 (coefficient of variation [CV] = 4.1%, n = 33), 0.93 (CV = 3.8%, n = 33), and 0.72 (CV = 2.9%, n = 10). Adjusted ordinary least square (OLS) regressions revealed associations (p ≤ 0.05) between sprint speed at 20 and 35 m and Yo-Yo IR1 test performance, but only between 35 m and IR2 test performance (p ≤ 0.05). Further, OLS showed that RSA at 35 m was related to both levels of the Yo-Yo IR test (p ≤ 0.01), and that submaximal HRs after 2 and 4 minutes were independently associated with Yo-Yo IR1 and IR2 performances (p ≤ 0.01). In conclusion, Yo-Yo IR1 and 2 test performances, as well as sprint and RSA performances, correlated very largely, and it may therefore be considered using only one of the Yo-Yo tests and a RSA test, in a general soccer-specific field test protocol. The submaximal HR measures during Yo-Yo tests are reproducible and may be used for frequent, time-efficient, and nonexhaustive testing of intermittent exercise capacity of high-level soccer players.

A Retrospective Study of the Yo-Yo IE2 Test: Can It be Used to Differentiate Between Different Levels of Futsal Referees?

Recently FIFA have called on referees to be fitter and to look like athletes therefore the aim of this research was to retrospectively examine the results from the fitness test results undertaken by Futsal referees operating in and below the National Futsal League. Futsal is the FIFA sanctioned form of 5 a side football and is controlled by two referees who operate up and down the touchlines either side of the pitch. Research has shown that the referees operating at an average intensity of 76% heart rate maximum (HRmax)HRMAX and spent more time sprinting and working at high intensity compared to referees in the 11 a side game. Currently FIFA recommend a. and as such the current 1000 m run, but this is not thought to match the actual movements or intensity of futsal referees or matches. As such the Yo-Yo IE2 test was introduced this season as it has been found to correlate highly with high intensity running (r=0.75; p<0.05). Twenty-two National group and 36 Non-national group futsal referees underwent pre-season testing which in-cooperating the Yo-Yo Intermittent Endurance Level 2 Fitness Test, a sprint test and a 70 m agility run test. The result showed a trivial effect size difference for Yo-Yo IE2 test distance (0.21), a small effect size difference for 40 m speed test and a extremely large effect size difference for agility run. A moderate to large correlation was found between age and Yo-Yo IE2 distance (r=-0.577) and BMI and Yo-Yo IE2 distance (r=-0.452). Therefore the Yo-Yo IE2 can be used to differentiate between different levels of futsal referees and it may be possible to use the test to identify those referees who show the fitness attributes for further development.

Relationship between performance characteristics and the selection process in youth soccer players.

The purpose of this study was to establish the anthropometric and physical profiles of elite young soccer players according to their playing position, and to determine their relevance for the selection process. One hundred and fifty-six young male soccer players participated in the study. Players were classified into the following groups: Goalkeepers (n=16), Central Defenders (n=26), External Defenders (n=29), Central Midfielders (n=34), External Midfielders (n=28), and Forwards (n=23). Anthropometric variables of participants (body height, body mass, body mass index, 6 skinfolds, 4 diameters, and 3 perimeters) were measured. Participants performed the Yo-Yo test, sprint tests (30 m flat sprint and Balsom agility test) and 2 jump tests (countermovement jump and the Abalakov test). At the end of the season, the technical staff of the club selected some of the players to continue playing on the same team and the rest were not selected. The results show that heavier and taller outfield players performed better in vertical jumps and sprint tests, whereas leaner outfield players performed better in the Yo-Yo test. Fat percentage of selected players was lower than that of the non-selected ones. The rest of the body components were similar in the selected and non-selected players within each playing position. Moreover, the selected players performed slightly better than the non-selected players in the physical test, but these differences were not statistically significant.

The investigation of heart rate variation on endurance of professional soccer players

The main aim of the present study was to determine whether performance on the Yo-Yo intermittent endurance test can predict the real match performances, or not. The sample of players consists of elite professional soccer players (age 23.02±4.49 years, soccer experience 10.04±4.2 years, body mass 73.61±6,15 kg, height 1,79 ±0,52 m, body mass index 19,12 ±0,4 kg m , body fat 8,32 ±2,96 %) who were the members of the 2 Turkish Soccer Federation. For assessment of aerobic endurance performance used, the Yo-Yo intermittent endurance test level 1 was performed. Heart rate was recorded by a Polar Vantage NV heart rate monitor placed around the chest for continuous heart rate recordings throughout selected stages of the test. Descriptive statistics were calculated. Data are expressed as means and standard deviations for each variable. It is seen that the research group uses 83 % of MaxHR in average Heart Rate according to minimum, average and maximum HR values obtained according to max HR values of the research group. As a conclusion, it is understood that heart rate is an important factor obtained from the yo-yo test that the soccer players show similar efforts during the competition. So the heart rate values taken from this test used as intermittent test has the quality to estimate the players match performance.

Reliability and validity of the Yo-Yo intermittent recovery test level 1 in young soccer players

The present study investigated the test-retest reliability from the Yo-Yo IR1 (distance and heart rate responses), and the ability of the Yo-Yo IR1 to differentiate between elite and non-elite youth soccer players. A total of 228 youth soccer players (11–17 years) participated: 78 non-elite players to examine the test-retest reliability within 1 week, added with 150 elite players to investigate the construct validity. The main finding was that the distance covered was adequately reproducible in the youngest age groups (U13 and U15) and highly reproducible in the oldest age group (U17). Also, the physiological responses were highly reproducible in all age groups. Moreover, the Yo-Yo IR1 test had a high-discriminative ability to distinguish between elite and non-elite young soccer players. Furthermore, age-related standards for the Yo-Yo IR1 established for elite and non-elite groups in this study may be used for comparison of other young soccer players.

Evaluation of a New Shirt-Based Electrocardiogram Device for Cardiac Screening in Soccer Players: Comparative Study With Treadmill Ergospirometry.

BackgroundPrevention of cardiac events during competitive sports is fundamental. New technologies with remote monitoring systems integrated into clothing could facilitate the screening of heart disease. Our aim was to evaluate the feasibility of Nuubo system during a field stress test performed by soccer players, comparing results with treadmill ergospirometry as test reference.MethodsNineteen male professional soccer players (19.2 ± 1.6 years) were studied. Wireless electrocardiographic monitoring during a Yo-Yo intermittent recovery test level 1 in soccer field and subsequent analysis of arrhythmias were firstly performed. Subsequently, in a period no longer than 4 weeks, each player underwent cardiopulmonary exercise testing in hospital.ResultsDuring Yo-Yo test, electrocardiogram (ECG) signal was interpretable in 16 players (84.2%). In the other three players, ECG artifacts did not allow a proper analysis. Estimation of maximum oxygen consumption was comparable between two exercise tests (VO2 max 53.3 ± 2.4 vs. 53.7 ± 3.0 mL/kg/min for Yo-Yo test and ergometry respectively; intra-class correlation coefficient 0.84 (0.63 - 0.93), P < 0.001). No arrhythmias were detected in any player during both tests.ConclusionsThe use of Nuubo’s technology allows an accurate single-lead electrocardiographic recording and estimation of reliable performance variables during exercise testing in field, and provides a new perspective to cardiac remote monitoring in collective sports.

Are Aerobic Fitness and Repeated Sprint Ability Linked to Fatigue in Professional Soccer Match-Play? A Pilot Study

Are Aerobic Fitness and Repeated Sprint Ability Linked to Fatigue in Professional Soccer Match-Play? A Pilot Study In professional soccer, a strong relationship has been observed between measures of physical fitness derived from tests of repeated sprint ability, intermittent endurance and aerobic capacity and running performance in competition determined from time motion analyses data. Unfortunately, these studies have generally only examined associations with ‘overall’ time motion measures of running performance such as the total distance run or that covered in sprinting. The potential relationship between fitness scores and declines in competitive physical performance in professional soccer players has up to now not received any attention despite the comprehensive body of research from time motion analyses that has indirectly demonstrated the existence of fatigue during matchplay. To our knowledge, only two studies, both conducted in elite youth soccer players, have addressed this gap in the literature. In the former for example, despite a significant association between intermittent-endurance fitness (Yo-Yo IR1 test) and overall distance covered in high-intensity activity, no relationship was observed between fitness measures and first- vs. second-half decrements in running distance.

Úroveň akceleračnej rýchlosti, explozívnej sily dolných končatín a špeciálnej vytrvalosti futbalových útočníkov

The purpose of the study was to analyse a level of sprint and jump abilities and intermittent endurance of forwards of Slovakia national soccer team category U21 (n = 5) in the period of classification for The UEFA European Under-21 Football Championship 2011. A level of sprint abilities was diagnosed by the apparatus FiTRO Light Gates (FiTRONIC, Bratislava, Slovak republic). The criterion of the assessment of the endurance was the time obtained in the distance of 10 m with the exactness 0.01 s. A level of jump abilities was diagnosed by the apparatus FiTRO Jumper (FiTRONIC, Bratislava, Slovak republic). The criterion of the evaluation was the highness of vertical jump from knee-bend/ squat with countermove and with the use of hand swing work in cm with the exactness 0,1cm. A level of intermittent endurance was diagnosed by Yo-Yo Intermittent recovery test level 2. The criterion of the assessment of the endurance was the distance (m) in Yo-Yo test. Differences in the level of sprint and jump abilities and intermittent endurance were recognised and defined by the expertise analysis. A level of sprint abilities of the object was presented by the average endurance with evaluation 2.20±0.06 s. A level of jump abilities was presented by the average endurance with evaluation 39.9±4.8 cm. A level of intermittent endurance was presented by the average endurance with evaluation 1304±288 meters equivalent converted at VO2max.kg-1 63.0±3.9 ml.kg-1.min-1. The expertise analysis of the level of sprint abilities has showed that one forward had significantly high level and one forward had significantly low level of sprint abilities when comparing with the average level of sprint abilities. The expertise analysis of the level of jump abilities has showed that one forward had significantly low level. The expertise analysis of the level of intermittent endurance has showed that one forward had significantly high level and one forward had significantly low level opposite to the average level of intermittent endurance of the object.

Match Performance and Physiological Capacity of Female Elite Team Handball Players

The present study evaluated the physical demands imposed on female elite team handball players in relation to playing position. Female elite team handball field players were examined during match-play over a 5-year period using video based computerized locomotion analysis of tournament matches. In addition, physiological measurements during match-play and in separate physical tests were carried out. A total distance of 4002±551 m (group means±SD) was covered per match with a total effective playing time of 50:42±5:50 min:s, while full-time players covered 4693±333 m. On average, each player (n=83) performed 663.8±99.7 activity changes per match, and the mean speed was 5.31±0.33 km · h(-1). High-intensity running constituted 0.8±0.5% of total effective playing time per match corresponding to 2.5±1.8% of the total distance covered. The amount of high-intensity running was reduced (p<0.05) 21.9% in the second half (44.9±16.8 m) compared to the first (57.5±21.3 m). Maximal oxygen uptake (VO2-max) was 3.49±0.37 l O2 · min(-1) corresponding to 49.6±4.8 ml O2 · min(-1) · kg(-1). Mean relative workload during match-play was 79.4±6.4% of VO2-max. Mean total running distance in the Yo-Yo intermittent recovery test (level 1) was 1436±222 m, which was greater in wing players (1516±172 m, p<0.05) than pivots (1360±118 m) and backcourt players (1352±148 m). In conclusion, modern female elite team handball is a physically demanding intermittent team sport, where players are exposed to high relative workloads with substantial estimated aerobic energy expenditure interspersed by short periods of dominant anaerobic energy production as reflected by the limited amount of high-intensity running. Indications of fatigue and a resulting decline in physical performance were identified, since the amount of high-intensity running and the relative workload levels decreased in the second half. Positional differences were observed, with wing players covering a greater total distance than backcourt players, performing more high-intensity running and demonstrating a better intermittent recovery capacity (Yo-Yo test outcome) compared to both backcourt players and pivots.

Cambios en las variables de desempeño físico en futbolistas sub-17 durante una pre-temporada

El objetivo del presente estudio consistió en verificar los cambios en las características antropométricas y fisiológicas de futbolistas de la categoría sub-17 de un club profesional. Se seleccionaron de forma no-probabilísticaaccidental 26 futbolistas que presentan un promedio de edad de 16,16±0,75 años al inicio de la pre-temporada y de 16,36±0,75 años al final de la pre-temporada. Se evaluaron las variables antropométricas de la estatura (cm), el peso corporal (kg), porcentaje de grasa (%g), masa grasa (kg) y masa muscular (kg) y las variables físicas del Yo-Yo test Intermitent Recovery (m), Yo-Yo test Endurance (VO2máx en ml/kg/min),velocidad de (20m), agilidad (segundos) y dos pruebas de saltos verticales squast jump (cm) y Contramoviment (cm). Para el análisis estadístico se utilizó la estadística descriptiva de media aritmética y desviación estándar, y para verificar las diferencias significativas se utilizó el test de Student y la prueba de especificidad de Tukey con una (p&lt;0,005). Los resultados muestran que no se encontraron diferencias significativas parael peso corporal total, el peso muscular y para la resistencia específica del Yo-Yo test Recovery. Sin embargo, los ocho microciclos de entrenamiento sí fueron suficientes estadísticamente para modificar el porcentaje de grasa, sumatoria de los pliegues cutáneos y el peso graso, a su vez mejoró la potencia aeróbica, la velocidad, la agilidad, la fuerza explosiva y la fuerza explosiva elástica, respectivamente.

Match performance and physical capacity of players in the top three competitive standards of English professional soccer

The aim of this study was to compare the match performance and physical capacity of players in the top three competitive standards of English soccer. Match performance data were collected from players in the FA Premier League (n=190), Championship (n=155) and League 1 (n=366) using a multiple-camera system. In addition, a selection of players from the Premier League (n=56), Championship (n=61) and League 1 (n=32) performed the Yo-Yo intermittent endurance test level 2 (Yo-Yo IE2) to determine physical capacity. Players in League 1 and the Championship performed more (p<.01) high-intensity running than those in the Premier League (Effect Size [ES]: 0.4–1.0). Technical indicators such as pass completion, frequency of forward and total passes, balls received and average touches per possession were 4–39% higher (p<.01) in the Premier League compared to lower standards (ES: 0.3–0.6). Players also covered more (p<.05) high-intensity running when moving down (n=20) from the Premier League to the Championship (ES: 0.4) but not when players moved up (n=18) standards (ES: 0.2). Similar Yo-Yo IE2 test performances were observed in Premier League, Championship and League 1 players (ES: 0.2–0.3). Large magnitude relationships (p<.05) were observed between Yo-Yo IE2 test performances and the total and high-intensity running distance covered in both Championship (r=.56 and .64) and Premier League matches (r=.61 and .54). The data demonstrate that high-intensity running distance was greater in players at lower compared to higher competitive standards despite a similar physical capacity in a subsample of players in each standard. These findings could be associated with technical characteristics inherent to lower standards that require players to tax their physical capacity to a greater extent but additional research is still required to confirm these findings.

Effects of Respiratory Muscle Training on Performance in Athletes

The purpose of this study was to perform a systematic review to determine if respiratory muscle training (RMT) improves sport performance and respiratory muscle strength and endurance. Methodology followed the Cochrane Collaboration protocol. MEDLINE, CINAHL, SPORTDiscus, PEDro, EMBASE, EBM reviews, and COCHRANE electronic databases were searched until July 2011. Articles were included if: (a) participants were athletes; (b) RMT was compared with sham or control in a randomized controlled design and included outcomes of respiratory muscle and sport performance; and (d) published in English. Quality assessment using PEDro and data abstraction was performed by 2 authors. Outcomes evaluated were measures of sport performance, exercise capacity, spirometry, and respiratory muscle strength and endurance. Meta-analyses were performed on outcomes reported in 2 or more papers. Results of this systematic review revealed that of the 6,923 citations retrieved from the search strategy, 21 met the inclusion criteria. Meta-analyses demonstrated a significant positive effect of RMT on sport performance outcomes of time trials, exercise endurance time, and repetitions on Yo-Yo tests. Inspiratory muscle strength and endurance improved in most studies, which in part, was dependent on the type of RMT employed. Determination of the type of athlete that may benefit most from RMT was limited by small sample sizes, differing RMT protocols, and differences in outcome measures across studies. In conclusion, RMT can improve sport performance. Closer attention to matching the ventilatory demands of RMT to those required during athletic competition and more aggressive progression of training intensity may show greater improvements in future studies.

The Order of Concurrent Training Does not Affect Soccer-Related Performance Adaptations

Despite the wealth of evidence regarding physical training strategies in soccer, there is little information regarding soccer-specific concurrent training and the effects of training order. The current study aimed to: i) quantify the effects of concurrent high-intensity run-based training (HIT) and strength- and power-based training (STR) on soccer-specific performance, and ii) investigate the order effect of completing HIT and STR either first or second within training sessions. Eighteen semi- and fully-professional players completed a battery of field- and gym-based tests before and after a 5-week pre-season training intervention. Players were pair-matched and completed 3 sessions per week of HIT followed by STR (n=9) or STR followed by HIT (n=9). ANCOVA tests revealed no differences between groups for changes in any of the measures (p>0.05). However, a training effect was observed for all measures (p<0.05), with 10-m sprint, 6×30-m repeated sprint, 40-m agility and Yo-Yo test performances improving by 1.8±2.6%, 1.3±1.8%, 1.0±1.5% and 19.4±23.4%, respectively (n=18). In conclusion, there was a positive effect of the concurrent training approach on key measures of soccer performance, but the order of completing HIT and STR appears inconsequential to performance adaptations.