Seasonal variation in physical performance-related variables in male NCAA Division III soccer players

Analysis of Accumulated Workloads and Performance Testing Across a Collegiate Women's Lacrosse Season

ABSTRACT

Fields, JB, Kuhlman, NM, Jagim, AR, Dulak-Sigler, C, and Jones, MT. Analysis of accumulated workloads and performance testing across a collegiate women's lacrosse season. J Strength Cond Res 37(11): 2213-2221, 2023-Monitoring accumulated workloads, acute:chronic workload ratios (ACWR), and training monotony (TM) are practical methods for monitoring athlete physical stress. Performance testing provides useful information about the changing nature of physical abilities. Therefore, the purpose was to examine differences in accumulated workloads based on session type, explore seasonal trends in ACWR and TM, and assess changes in performance assessments in collegiate women's lacrosse athletes. Athletes, who were identified as starters ( n = 12), wore positional monitoring technology during training sessions ( n = 61) and games ( n = 17) and completed preseason and postseason assessments of speed, agility, power (jump tests), strength, aerobic capacity, and body composition. Separate 1-way analyses of variance were used to determine differences in accumulated workloads for session type and differences in performance assessments from preseason to postseason ( p < 0.05). When compared with games, practice sessions elicited greater ( p < 0.001) accumulated total distance, player load, repeated high-intensity efforts, accelerations, change of direction, explosive efforts, high-speed efforts ( p = 0.002), and high-speed distance ( p = 0.002). Throughout the season, ACWR and TM ranged from 0.16 to 1.40 AU and 0.68-1.69 AU, respectively. The 40-yd sprint ( p < 0.001) and pro-agility ( p < 0.001) improved from preseason to postseason, whereas no changes in aerobic capacity, lower-body power, or strength were observed ( p > 0.05). The monitoring of accumulated loads, ACWR and TM, and performance tests revealed novel information about the seasonal demands of collegiate women's lacrosse. Women lacrosse players are able to improve speed and agility throughout the season, while maintaining strength, power, and endurance, with minimal reductions in fat-free mass.

How Different Predominant SARS-CoV-2 Variants of Concern Affected Clinical Patterns and Performances of Infected Professional Players during Two Soccer Seasons: An Observational Study from Split, Croatia

There are limited data describing clinical patterns and match running performance (MRP) among players with COVID-19 infection before and after infection, particularly related to different predominant SARS-CoV-2 variants, as well as in comparison to uninfected players. This observational study was conducted during two consecutive soccer seasons in one professional club in Split, Croatia. There were four clusters of mild, self-limited, or asymptomatic infection characterised by low adherence to preventive measures. Infected players had significantly more symptoms (t-test = 3.24; p = 0.002), a longer period of physical inactivity (χ² = 10.000; p = 0.006) and a longer period of self-assessment for achieving full fitness (χ² = 6.744; p = 0.034) in the 2020-2021 season (Wuhan wild strain and Alpha variant) than in the 2021-2022 season (Omicron variant). It was also found that, despite the milder clinical presentation of the infection in the 2021-2022 season, the players had significantly more abnormal laboratory findings (χ² = 9.069240; p = 0.002), although without clinical significance at the time of the study. As for the MRP, player performance in the 2021-2022 season was not negatively affected by the Omicron variant, while there was an improvement in MRP in scores for a sample of all players. The RTP protocol was correctly applied because it helped the athletes to recover their pre-infection physical capacities relatively quickly. This study advances the understanding that an optimally and individually planned RTP protocol is crucial for the MRP of infected players. Future research needs to replicate the findings of abnormal laboratory results and extend the study focusing on their potential long-term clinical significance.

The soccer season: performance variations and evolutionary trends

The physiological demands of soccer challenge the entire spectrum of the response capacity of the biological systems and fitness requirements of the players. In this review we examined variations and evolutionary trends in body composition, neuromuscular and endurance-related parameters, as well as in game-related physical parameters of professional players. Further, we explore aspects relevant for training monitoring and we reference how different training stimulus and situational variables (e.g., competition exposure) affect the physiological and performance parameters of players. Generally, improvements of small magnitude in non- (non-CMJ) and countermovement-based jumps (CMJBased) and in the sprint acceleration (ACCPhase) and maximal velocity phase (MVPhase) are observed from start of preparation phase (PPS) to beginning of competition phase (BCP). A greater magnitude of increases is observed in physiological and endurance performance measures within this period; moderate magnitude in sub-maximal intensity exercise (velocity at fixed blood lactate concentrations; V2-4mmol/l) and large magnitude in VO2max, maximal aerobic speed (MAS) and intense intermittent exercise performance (IE). In the middle of competition phase (MCP), small (CMJBased and ACCPhase), moderate (non-CMJ; MVPhase; VO2max; sub-maximal exercise) and large (MAS and IE) improvements were observed compared to PPS. In the end of competition period (ECP), CMJBased and MVPhase improve to a small extent with non-CMJ, and ACCPhase, VO2max, MAS, sub-maximal intensity exercise and IE revealing moderate increments compared to PPS. Although less investigated, there are generally observed alterations of trivial magnitude in neuromuscular and endurance-related parameters between in-season assessments; only substantial alterations are examined for IE and sub-maximal exercise performance (decrease and increase of small magnitude, respectively) from BCP to MCP and in VO2max and IE (decrements of small magnitude) from MCP to ECP. Match performance may vary during the season. Although, the variability between studies is clear for TD, VHSR and sprint, all the studies observed substantial increments in HSR between MCP and ECP. Finally, studies examining evolutionary trends by means of exercise and competition performance measures suggests of a heightened importance of neuromuscular factors. In conclusion, during the preseason players "recover" body composition profile and neuromuscular and endurance competitive capacity. Within in-season, and more robustly towards ECP, alterations in neuromuscular performance seem to be force-velocity dependent, and in some cases, physiological determinants and endurance performance may be compromised when considering other in-season moments. Importantly, there is a substantial variability in team responses that can be observed during in-season. Consequently, this informs on the need to both provide a regular training stimulus and adequate monitorization throughout the season.

Peripheral muscle function during repeated changes of direction in professional soccer players

PURPOSES

To evaluate peripheral muscle function of the knee extensors during repeated changes of direction in professional soccer players by examining differences between competitive levels, periods of the season and playing positions, and to investigate the relationships between peripheral muscle function and physical activities during matches.

METHODS

Knee extensor peripheral muscle function (twitch peak torque, PT) of 593 male soccer players from 13 European professional clubs competing at 3 different levels was evaluated 4 times during the season. The main outcomes were PT_max (maximal PT, muscle contractility), MP_max (maximal metabolic power exercise intensity) and PT_dec (PT decline, muscle fatigability) obtained during intermittent runs of increasing intensity with multiple changes of direction interspersed with electrically evoked contractions. Relative total and sprint distances covered during a whole match and during short intervals were quantified from a sub-sample.

RESULTS

PT_max and MP_max were higher for first than for second division (p < 0.047; d = 0.15-0.23) and Under-19 players (p < 0.007; d = 0.17-0.25). MP_max was lower (p < 0.016; d = 0.23-0.32) and PT_dec was higher (p < 0.004; d = 0.26-0.39) in the pre-season compared to all the other time points. MP_max was higher for fullbacks than attackers and defenders (p < 0.041; d = 0.20-0.22). PT_dec was higher for defenders than fullbacks, midfielders and wings (p < 0.029; d = 0.21-0.28). PT_max was associated with whole-match relative total distance (p = 0.004; d = 0.26). PT_dec was associated with whole-match relative total distance and relative short-interval sprint distance (p < 0.050; d = 0.18-0.22).

CONCLUSION

The ability to sustain repeated change of direction efforts at high intensities while preserving peripheral muscle function should be considered an important determinant of soccer physical performance.

Physical fitness changes among amateur soccer players: effects of the pre-season period

Study aim: To assess changes in physical fitness of amateur soccer players after a pre-season training period and baseline fitness dependencies.

Material and methods: Twenty-one amateur soccer players were assessed during the pre-season. The following physical variables were assessed before and after a two-month pre-season training period: (i) cardiorespiratory fitness, (ii) strength and power, and (iii) change of direction (COD).

Results: Significant decreases were found for countermovement jump (CMJ) (p < 0.001; d = 1.161), drop jump (DJ) (p = 0.014; d = 0.958), and horizontal jump (HJ) (p = 0.042; d = 0.640), while no significant changes were found for the overall variables from the beginning to the end of pre-season. Fit players revealed significant decreases for CMJ (p = 0.002; d = –2.495), DJ (p = 0.004; d = –1.760), HJ (p = 0.028; d = –1.005), COD deficit (p = 0.034; d = 1.013), and maximal aerobic speed (MAS) (p = 0.026; d = –4.053). No significant changes were found for unfit players.

Conclusions: Amateur soccer coaches should consider assessing physical qualities at the beginning of pre-season and use the free-of-charge monitoring tools such as session-rate of perceived exertion (s-RPE) during the training process.

Relationships Between Measures of Functional and Isometric Lower Body Strength, Aerobic Capacity, Anaerobic Power, Sprint and Countermovement Jump Performance in Professional Soccer Players

The purpose of this study was to assess a wide range of physiological and performance variables and investigate whether and to what extent these variables are associated with each other in soccer. Twenty-five male soccer players (25.1 ± 4.56 years; body mass, 75.2 ± 5.92 kg; body height, 180.6 ± 5.45 cm) performed: 5- and 30-m sprints (T5m and T30m, respectively), 1-repetition-maximum (1RM) half squat, maximal voluntary isometric contraction (MVIC) of the knee extensors, countermovement jump (CMJ) to obtain vertical jump height (CMJ_height) and power output (CMJ_power), the 10-s Wingate Anaerobic Test (WAnT) to obtain peak power (P_max), and the 20-m multi-stage shuttle run test (MST) to evaluate aerobic capacity. 1RM, MVIC, and P_max were normalized to body mass. Large negative correlations were found between sprint times and 1RM half back squat/BM (r = -0.510 to -0.570, r² = 0.260–0.325, both p < 0.01) and P_max/BM (r = -0.501, r² = 0.251, p < 0.01). T30m most strongly and negatively correlated with CMJ_height (r = -0.744, r² = 0.554, p < 0.001). WAnT-determined P_max showed a very large correlation between absolute P_max and knee-extensor MVIC (r = 0.827, r² = 0.684, p < 0.001) and large correlations between absolute P_max and 1RM half squat (r = 0.674, r² = 0.454, p < 0.001) and CMJ_power (r = 0.579, r² = 0.335, p < 0.01). We also identified a large inverse relationship between CMJ_height and T30m (r = -0.744, r² = 0.554, p < 0.001) and large positive correlation between CMJ_height and MVIC/BM (r = 0.702, p < 0.001). The results demonstrate that elite soccer players with greater lower body strength (quantified by the MVIC of the knee extensor and the 1RM half squat) show better sprint and CMJ performance, suggesting the incorporation of soccer-specific resistance training to develop lower body musculature and therefore maximize sprinting ability. The higher correlation coefficients found between T30m and the physiological and athletic measures compared with T5m promote the use of this sprint distance when assessing performance. The use of relative measures (normalized to body mass) is advisable when comparing strength variables with sprint and CMJ performance or anaerobic power. Considering the correlations of WAnT-determined P_max versus CMJ_power, coaches should administer tests that assess jumping and linear sprint performance rather than the cycling-specific WAnT.

Seasonal Repeated Sprint Ability With Change of Direction Variations in U17 and U20 Elite Brazilian Soccer Players: A Comparative Study

Jorge, G, Garrafoli, MT, and Cal Abad, CC. Seasonal repeated sprint ability with change of direction variations in U17 and U20 elite Brazilian soccer players: a comparative study. J Strength Cond Res 34(5): 1431-1439, 2020-This study aimed to describe seasonal variations of repeated sprint with change-of-direction ability in young elite Brazilian soccer players. The Bangsbo sprint test (BST) was performed by 21 under-17 (U17) (176.9 cm; 68.2 kg) and 22 under-20 (U20) athletes (178.7 cm, 74.4 kg) at the start, middle, and end of the season. The fatigue index (FI) was calculated in seconds and in percentage of decrease (%D) for comparisons. Both age categories showed higher BST performance in the middle and end compared with the start of the season (p ≤ 0.05). The U20 players performed better at the start than the U17 players. The U17 soccer players showed higher FI at the start and in the middle in comparison with the U20 players (p ≤ 0.05). They also showed lower FI at the end of the season in comparison with the start and middle of the season (p ≤ 0.05). The U20 players showed significant reductions in the FI in the middle and at the end in comparison with the start of the season (p ≤ 0.05). Only the U17 soccer players showed lower %D at the end in comparison with the start of the season (p ≤ 0.05). To summarize, both U17 and U20 players performed BST poorly at the start, increased the BST performance until the middle, and maintained the BST performance until the end of the season. A difference in the magnitude of enhancement was observed between U17 and U20 soccer players, which was found to be dependent on the initial values. Finally, the mathematical model to calculate the FI requires caution.

Evolution of contractile properties of the lower limb muscles throughout a season in elite futsal players

BACKGROUND

Futsal is a team sport involving intermittent technical actions of high intensity, and high physical (strength) and muscular demands. In this regard, the tensiomyography (TMG) is a useful and non-invasive tool for the monitoring and assessment of the muscle's contractile capacity. This study aimed to analyze the changes in the contractile properties produced during the season, as well as to determine the potential cumulative effect of a resistance training (RT) program in futsal players.

METHODS

Fourteen elite futsal players (2 goalkeepers, 4 defenders, 4 wingers and 3 pivots) were assessed by TMG at 11th, 18th, and 28th week of the season. The maximal radial displacement of the muscle belly (Dm); contraction time (Tc); delay time (Td) and radial displacement velocity (90%) Dm (VrD90) were assessed. After the second measurement, a RT program was included in the regular training sessions and focused on the lower body musculature. It was performed during 9 weeks (1-weekly). Finally, a third measurement was performed between 28th-29th weeks. Repeated measures analysis of variance was used to detect in-season changes. Two factors were included: Time (changes detected after resistance training program) was used as the within-subject factor and the specific position was used as the between-subject factor.

RESULTS

An increment in Tc for several muscles: biceps femoris (BF; P=0.02), semitendinosus (ST; P=0.04), adductor longus (AL; P=0.008) and gastrocnemius medialis (GM; P=0.009) was observed throughout the season. Similarly, significant increments in Dm for GM (P=0.02) and AL (P=0.05), as well as increments in Td for BF (P=0.002) were found. Moreover, no significant changes in VrD90 between time points 2-3 (analysis of RT effect) were observed. Additionally, the player´s positions reported no significant changes for any of the variables analyzed.

CONCLUSIONS

An increase respect to baseline levels was observed for Tc, Td and Dm during the season. However, the adaptations to contractile properties were muscle specific. In addition, an in-season 9-week RT program (1-weekly), had no significant effects (time points 2-3) on the contractile properties of futsal players. In addition, there were no differences when comparing different positions.

Pre-season Fitness Level and Injury Rate in Professional Soccer - A Prospective Study

The aim of the present study was to assess prospectively the effect of pre-season fitness on injury rate during the competitive season among professional soccer players. Thirty-one players participated in the study during two consecutive competitive seasons (2015-16 and 2016-17; a squad of 22 players in each season). During the 6-week pre-season training period (8 training sessions and a friendly match every week, 14-18 training hours/week) there was a significant improvement in VO ₂ max, a significant increase in ideal and total sprint time and no change in vertical jump, flexibility and repeated sprint-test performance decrement. During the two consecutive seasons, 28 injuries were recorded. Ten injuries were classified as mild (missing 3-7 days of practice/match), 8 as moderate (missing 8-28 days) and 10 as severe (missing >28 days). The rate of match injuries was higher (9.4 per 1000 match hours) compared to practice injuries (4.7 per 1000 training hours). Most injuries were overuse injuries (72%) of the lower limbs (71%). Most of match injuries occurred during the last 15 min of each half. There were no differences in fitness characteristics in the beginning of pre-season training between injured and non-injured players. However, improvements in VO ₂ max during the pre-season training period were significantly lower among injured players (0.9±5.5%) compared to non-injured players (10.4±6.5%, p<0.05). Our results emphasize the importance of pre-season training in professional soccer players not only for improvement in fitness but also for injury prevention during the following competitive season.

The Physical and Athletic Performance Characteristics of Division I Collegiate Female Soccer Players by Position

Lockie, RG, Moreno, MR, Lazar, A, Orjalo, AJ, Giuliano, DV, Risso, FG, Davis, DL, Crelling, JB, Lockwood, JR, and Jalilvand, F. The physical and athletic performance characteristics of Division I collegiate female soccer players by position. J Strength Cond Res 32(2): 334-343, 2018-Playing positions in soccer can exhibit different movement demands during a match, contributing to variations in physical and performance characteristics. National Collegiate Athletic Association (NCAA) soccer features different substitution rules when compared to FIFA-sanctioned matches, which could influence each players' characteristics. Therefore, this study determined the athletic performance characteristics of Division I female soccer players. Twenty-six players (3 goalkeepers; 8 defenders; 10 midfielders; 5 forwards) from the same squad completed assessments of: lower-body power (vertical and standing broad jump); linear (0-5, 0-10, 0-30 meter [m] sprint intervals) and change-of-direction (pro-agility shuttle; arrowhead change-of-direction speed test) speed; and soccer-specific fitness (Yo-Yo Intermittent Recovery Test [YYIRT] levels 1 and 2). Players were split into position groups, and a Kruskal-Wallis H test with post hoc pairwise analyses (p ≤ 0.05) calculated significant between-group differences. There were no differences in age, height, or body mass between the positions. Midfielders had a faster 0-5 m time compared with the defenders (p = 0.017) and the goalkeepers (p = 0.030). The defenders (p = 0.011) and midfielders (p = 0.013) covered a greater YYIRT2 distance compared with the goalkeepers. There were no other significant between-position differences. Overall, Division I collegiate female players from the same squad demonstrated similar characteristics as measured by soccer-specific performance tests, which could allow for flexibility in position assignments. However, a relatively homogenous squad could also indicate commonality in training prescription, particularly regarding acceleration and high-intensity running. Strength and conditioning coaches may have to consider the specific movement demands of individual positions when training these capacities.

Relationships between Linear Speed and Lower-Body Power with Change-of-Direction Speed in National Collegiate Athletic Association Divisions I and II Women Soccer Athletes

This study investigated relationships that linear speed and lower-body power have on change-of-direction (COD) speed in collegiate women soccer players. Data from two Division I (n = 39) and one Division II (n = 18) schools were analyzed. Subjects were assessed in: power (vertical jump (VJ); jump height, peak anaerobic power measured in watts (PAPw), power-to-body mass ratio (P:BM); linear speed (10-m sprint); and COD speed (modified T-test (MTT), 505, COD deficit). Independent samples T-tests derived significant between-group differences, with effect sizes (d) calculated. Pearson&rsquo;s correlations determined relationships between COD speed, linear speed, and power, with regression equations calculated. Division I players demonstrated superior 505, COD deficit, VJ height, PAPw, and P:BM (d = 1.09⁻2.21). Division II players were faster in the MTT (d = 1.51). For all players, the 505 correlated with the 10-m sprint (r = 0.39⁻0.53) and VJ height (r = &minus;0.65⁻0.66), while the COD deficit related to the 10-m sprint (r = &minus;0.77⁻0.82). The regression data supported these results. Division I players were superior in the 505 and COD deficit, and expressed their power in the 180&deg; 505 task. Division II players should enhance lower-body power and the ability to perform 180&deg; direction changes.

Seasonal Variations in Physical Fitness and Performance Indices of Elite Soccer Players

The aim of the study was to investigate seasonal variations in fitness and performance indices of professional male soccer players. Eighteen professional male soccer players (age range 22–32 years) completed three similar sets of tests at three stages of the season: before preseason; after preseason and the middle of the competitive in-season. A significant decrease in body mass and percent fat was found during the preseason. A significant improvement (p < 0.05) was found in the vertical jump (preseason: 37.0 ± 5.3, post-preseason: 39.0 ± 4.8, mid-season: 40.3 ± 5.5 cm), the 4 × 10-m agility test (preseason: 8.1 ± 0.2, post-preseason: 7.9 ± 0.2, mid-season: 8.1 ± 0.3 s), flexibility (preseason: 45.2 ± 8.8, post-preseason: 48.2 ± 7.0, mid-season: 49.9 ± 6.9 cm) and aerobic capacity (preseason: 52.7 ± 6.6, post-preseason: 56.4 ± 6.0, mid-season: 57.4 ± 5.4 mL/kg/min) during preseason, with no further change during mid-season. Repeated sprint test (RST) (6 × 30-m) performance indices showed significant deterioration (p < 0.05) in ideal sprint time (IS; preseason: 21.8 ± 1.0, post-preseason: 23.0 ± 0.8, mid-season: 23.2 ± 0.8 s) and total sprint time (TS; preseason: 22.5 ± 0.7, post-preseason: 23.5 ± 0.6, mid-season: 23.8 ± 0.6 s) during preseason, with no further changes during mid-season. However, performance decrement (PD) significantly decreased during the preseason with no change during mid-season. The findings suggest that while power training was probably responsible for the anaerobic fitness improvement, the high-volume training led to improvement in aerobic fitness during the preseason. However, the low-intensity aerobic-type training, coupled with the high total training load, may have led to fatigue and decreases in IS and TS during the preseason.

Preseason Maximal Aerobic Power in Professional Soccer Players Among Different Divisions

Marcos, MA, Koulla, PM, and Anthos, ZI. Preseason maximal aerobic power in professional soccer players among different divisions. J Strength Cond Res 32(2): 356-363, 2018-The purpose of this study was to examine and compare the anthropometric, maximal oxygen uptake (V[Combining Dot Above]O2max), and positional differences of first division (D1) professional football players from players of second (D2) and third (D3) divisions in Cyprus football leagues. Four hundred twenty-one professional male football players participated in this study. All subjects underwent anthropometric and body composition evaluation. In addition, they performed an incremental cardiopulmonary exercise testing (CPET) on a treadmill for V[Combining Dot Above]O2max evaluation. The results were analyzed using 1-way analysis of variance, between subjects design revealing significant effects among the divisions. Tukey's honest significant difference (HSD) tests demonstrated that players from D1 scored significantly higher on V[Combining Dot Above]O2max and lasted significantly longer on the treadmill than participants of D2 and D3 (p ≤ 0.05). Similar findings were demonstrated when D2 was contrasted against D3 players. Goalkeepers, defenders, and forwards demonstrated significantly higher anthropometric measurements, whereas wingers and midfielders demonstrated significantly higher V[Combining Dot Above]O2max (p ≤ 0.05) than goalkeepers and defenders. The findings of this study clearly demonstrated that cardiovascular fitness, as determined by CPET, is an important fitness parameter that differentiates professional football players who play at a more advanced level. This could be attributed to the different seasonal schedules that allow for longer transition time for lower division players and thus favoring greater detraining effects. Emphasis should be given by fitness professionals on transition period training to minimize the detraining effects especially in lower divisions.

Efficacy of downhill running training for improving muscular and aerobic performances

This study investigated effects of downhill (DR) versus level (LR) running training on various muscular and aerobic performances. Eighteen healthy young males conducted either DR (DR group (DRG), n = 10: -10% slope) or LR (LR group (LRG), n = 8) training at a target heart rate (HR) associated with lactate threshold (LT) for 20 min·session^-1, 3 sessions·week^-1, for 5 weeks. Before and after the interventions, the following variables were measured: knee extension torque (-150, -30, 0, 30, 150°·s^-1), leg extension power (simultaneous hip and knee extension: 0.8 m·s^-1), squat and countermovement jump height, rebound jump index (jump height·contact time^-1), 20-m linear sprint and change-of-direction (Pro-agility and V-cut tests) time, and aerobic capacity (maximal oxygen uptake, energy cost at LT, and velocity at maximal oxygen uptake and LT) on a level surface. Throughout the training sessions, HR during running did not differ between the groups (DRG: 77.7% ± 4.6% vs LRG: 76.4% ± 4.6% of maximal HR; average across all sessions), while velocity was significantly higher for DRG (14.5 ± 1.1 vs 12.0 ± 1.9 km·h^-1). After the training, DRG significantly improved knee extension torque at all angular velocities (9%-24%) and change-of-direction time for both tests (2%-3%), with no changes in other parameters. LRG significantly improved maximal oxygen uptake (5%), energy cost at LT (3%), and velocity at maximal oxygen uptake (7%), without changes in others. These results suggest that DR training has a greater potential to improve the knee extension strength and change-of-direction ability, but has little effect on the aerobic capacity, compared with HR-matched LR training.

Relationships and Predictive Capabilities of Jump Assessments to Soccer-Specific Field Test Performance in Division I Collegiate Players

Leg power is an important characteristic for soccer, and jump tests can measure this capacity. Limited research has analyzed relationships between jumping and soccer-specific field test performance in collegiate male players. Nineteen Division I players completed tests of: leg power (vertical jump (VJ), standing broad jump (SBJ), left- and right-leg triple hop (TH)); linear (30 m sprint; 0–5 m, 5–10 m, 0–10, 0–30 m intervals) and change-of-direction (505) speed; soccer-specific fitness (Yo-Yo Intermittent Recovery Test Level 2); and 7 × 30-m sprints to measure repeated-sprint ability (RSA; total time (TT), performance decrement (PD)). Pearson’s correlations (r) determined jump and field test relationships; stepwise regression ascertained jump predictors of the tests (p < 0.05). All jumps correlated with the 0–5, 0–10, and 0–30 m sprint intervals (r = −0.65–−0.90). VJ, SBJ, and left- and right-leg TH correlated with RSA TT (r = −0.51–−0.59). Right-leg TH predicted the 0–5 and 0–10 m intervals (R² = 0.55–0.81); the VJ predicted the 0–30 m interval and RSA TT (R² = 0.41–0.84). Between-leg TH asymmetry correlated with and predicted left-leg 505 and RSA PD (r = −0.68–0.62; R² = 0.39–0.46). Improvements in jumping ability could contribute to faster speed and RSA performance in collegiate soccer players.

Physiological Characteristics of Incoming Freshmen Field Players in a Men's Division I Collegiate Soccer Team

Freshmen college soccer players will have lower training ages than their experienced teammates (sophomores, juniors, seniors). How this is reflected in field test performance is not known. Freshmen (n = 7) and experienced (n = 10) male field soccer players from the same Division I school completed soccer-specific tests to identify potential differences in incoming freshmen. Testing included: vertical jump (VJ), standing broad jump, and triple hop (TH); 30-m sprint, (0–5, 5–10, 0–10, and 0–30 m intervals); 505 change-of-direction test; Yo-Yo Intermittent Recovery Test Level 2 (YYIRT2); and 6 × 30-m sprints to measure repeated-sprint ability. A MANOVA with Bonferroni post hoc was conducted on the performance test data, and effect sizes and z-scores were calculated from the results for magnitude-based inference. There were no significant between-group differences in the performance tests. There were moderate effects for the differences in VJ height, left-leg TH, 0–5, 0–10 and 0–30 m sprint intervals, and YYIRT2 (d = 0.63–1.18), with experienced players being superior. According to z-score data, freshmen had meaningful differences below the squad mean in the 30-m sprint, YYIRT2, and jump tests. Freshmen soccer players may need to develop linear speed, high-intensity running, and jump performance upon entering a collegiate program.

The relationship between body composition and preseason performance tests of collegiate male lacrosse players

Numerous studies have examined the effects that body composition has on performance in football, soccer, and ice hockey; yet, there are no similar studies examining this relationship in men's lacrosse. The purpose of the study was to examine the physiological profiles and the relationship between body composition and performance in aerobic and anaerobic tests. Fifty-four (19.63 ± 1.21 years; 178.53 ± 6.17 cm; 81.66 ± 14.96 kg) Division III intercollegiate athletes participated. Performance tests, including a 1 repetition maximum power clean (PC), body weight (lbs), bench press repetitions, parallel bar triceps dips to fatigue (DR), two 300-yard shuttles, and a 1-mile run (MT), were completed after the completion of fall preseason practices. Body composition was estimated using air-displacement plethysmography. Correlation coefficients determined relationships between percent body fat (%BF), fat-free mass (FFM), and testing variables. Increased %BF was negatively correlated to DR (r = -0.36, p = 0.01) whereas positively correlated to each 300-yard shuttle time (T1 and T2), total 300-yard shuttle time (TT), and MT (r = 0.64, p = 0.00; r = 0.68, p = 0.00; r = 0.69, p = 0.00; and r = 0.44, p = 0.00, respectively). Increased FFM was positively correlated with PC (r = 0.58, p = 0.00) yet not correlated (p ≥ 0.05) with other variables. Results indicated that increased %BF might be a detriment to the repetitive anaerobic performance and aerobic capacity vital to on-field lacrosse performance. Body composition also demonstrated a significant relationship to moving internal vs. external resistances.

Comparison of Two Kinds of Endurance Training Programs on the Effects of the Ability to Recover in Amateur Soccer Players

Background:

High intensity intermittent aerobic exercise is an elementary endurance training exercise to build soccer endurance. Many studies exist with professional soccer players. But limited research has been conducted with amateur soccer players.

Objectives:

The aim of this study was to compare and assess the effects of the shuttle-run method and the Hoff-track method on the ability to recover in amateur soccer players within three weeks.

Patients and Methods:

Two amateur soccer teams were randomly assigned to shuttle-run group (n = 24; SRG) (SRG: shuttle-run group) or Hoff-track group (n = 18; HTG) (HTG: hoff-track group). They performed 2 times/week over three weeks their program. SRG performed a 20 m high speed shuttle-run until exhaustion and HTG covered at their highest speed level an obstacle track. Before and after training the yo-yo intermittent recovery test level 2 (YYIRTL2) was conducted.

Results:

Significant differences were observed within (P < 0.05) and between the groups (P = 0.06; ES = 0.50) in distance covering during YYIRTL2.

Conclusions:

Both training methods seem to improve the ability to recover in amateur soccer players within a short time period during the competition season.

An elliptical trainer may render the Wingate all-out test more anaerobic

The purpose of this study was to evaluate the contribution of the 3 main energy pathways during a 30-second elliptical all-out test (EAT) compared with the Wingate all-out test (WAT). Participants were 12 male team sport players (age, 20.3 ± 1.8 years; body mass, 74.8 ± 12.4 kg; height, 176.0 ± 9.10 cm; body fat, 12.1 ± 1.0%). Net energy outputs from the oxidative, phospholytic, and glycolytic energy systems were calculated from oxygen uptake data recorded during 30-second test, the fast component of postexercise oxygen uptake kinetics, and peak blood lactate concentration, respectively. In addition, mechanical power indices were calculated. The main results showed that compared with WAT, EAT was characterized by significantly lower absolute and relative contributions of the oxidative system (16.9 ± 2.5 J vs. 19.8 ± 4.9 J; p ≤ 0.05 and 11.2 ± 1.5% vs. 15.7 ± 3.28%; p ≤ 0.001). In addition, significantly greater absolute and relative contributions of the phospholytic system (66.1 ± 15.8 J vs. 50.7 ± 15.9 J; p ≤ 0.01 and 43.8 ± 6.62% vs. 39.1 ± 6.87%; p ≤ 0.05) and a significantly greater absolute contribution of the glycolytic system (68.6 ± 18.4 J vs. 57.4 ± 13.7 J; p ≤ 0.01) were observed in EAT compared with WAT. Finally, all power indices, except the fatigue index, were significantly greater in EAT than WAT (p ≤ 0.05). Because of the significantly lower aerobic contribution in EAT compared with WAT, elliptical trainers may be a good alternative to cycle ergometers to assess anaerobic performance in athletes involved in whole-body activities.

Impact of the FIFA 11+ on the structure of select muscles in adolescent female soccer players

OBJECTIVES

To determine the impact of an injury prevention program (FIFA11+) on the structure of select trunk and leg muscles in adolescent female soccer players.

DESIGN

Exploratory analysis.

SETTING

University Sport Medicine Centre.

PARTICIPANTS

23 female soccer players (aged 14-16) recruited from a FIFA11 + implementation trial grouped by high and low 11 + exposure.

MAIN OUTCOMES

Pre and post-season sonographic measures of the rectus abdominis, external and internal oblique, transversus abdominis, inter-recti distance (IRD), lumbar multifidus, gluteus medius and minimus, and vastus medialis. Mean (95% confidence intervals; CI) were calculated for pre, post and pre-post season change of all parameters and univariate analyses used to compare groups (α = 0.001).

RESULTS

Both low (mean = 149 ± 9 exercises/year) and high (mean = 314 ± 15 exercises/year) 11 + exposure groups demonstrated significant post-season decreases in IRD at rest (p < 0.001) and during a leg lift (p < 0.001). No other between or within group differences existed.

CONCLUSIONS

Levels of FIFA11 + exposure were not associated with differential changes in the morphology of investigated muscles. As the IRD of participants in both exposure groups decreased it is possible that the protective mechanism of the FIFA11 + may be associated with alterations in neuromuscular control that result in abdominal wall adaptations.

Cut points of muscle strength associated with metabolic syndrome in men

INTRODUCTION

The loss of muscle strength with age increases the likelihood of chronic conditions, including metabolic syndrome (MetS). However, the minimal threshold of muscle strength at which the risk for MetS increases has never been established.

OBJECTIVE

This study aimed to identify a threshold of muscle strength associated with MetS in men.

METHODS

We created receiver operating curves for muscle strength and the risk of MetS from a cross-sectional sample of 5685 men age <50 yr and 1541 men age ≥50 yr enrolled in the Aerobics Center Longitudinal Study. The primary outcome measure, the MetS, was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Upper and lower body muscle strength was treated as a composite measure of one-repetition maximum tests on bench and leg press and scaled to body weight. Low muscle strength was defined as the lowest age-specific 20th percentile, whereas high muscle strength was defined as composite muscle strength above the 20th percentile.

RESULTS

In men aged <50 yr, the odds of MetS were 2.20-fold (95% confidence interval = 1.89-2.54) higher in those with low muscle strength, independent of age, smoking, and alcohol intake. The strength of this association was similar for men age ≥50 yr (odds ratio = 2.11, 95% confidence interval = 1.62-2.74). In men age < 50 yr, the composite strength threshold associated with MetS was 2.57 kg·kg body weight, whereas in men age ≥ 50 yr the threshold was 2.35 kg·kg body weight.

CONCLUSION

This study is the first to identify a threshold of muscle strength associated with an increased likelihood of MetS in men. Measures of muscle strength may help identify men at risk of chronic disease.

Relations between BMI, Body Mass and Height, and Sports Competence among Participants of the 2010 Winter Olympic Games: Does Sport Metabolic Demand Differentiate?

This study characterizes the athletes participating in the 2010 Winter Olympic Games in terms of body height, body mass and BMI. The studied sample consisted of athletes in the top 20 places of each of 14 sports disciplines (1460 cases). Data on the athletes' age, height, body mass, and sports specialization were obtained from the Olympic Games' official website and from the International Ski Federation. The sampled athletes were grouped according to the predominant type of energy metabolism during competition. The anaerobic-glycolytic disciplines, such as cross-country sprint, figure skating, short track, and speed skating (500,1000 and 1500 m), were found to have the youngest female athletes: 25.0 yr. ( SD = 4.7). In the endurance sports (aerobic and aerobic-anaerobic), the female athletes were the oldest, being respectively 28.6 yr. ( SD = 4.9) and 28.1 yr. ( SD = 4.5) old. In the speed disciplines (anaerobic-alactic), the female athletes were the tallest ( M = 172 cm; SD = 8.3). The male athletes in the anaerobic-alactic sports were the tallest ( M = 181.8 cm, SD = 6.7) and those in the anaerobic-glycolytic sports were the shortest ( M = 179.2 cm, SD = 6.7). The large differences in body mass among the groups of athletes, which appear to be related to the predominant type of metabolism during competition, show that this parameter is partly correlated with the level of sports competence, but only in disciplines where the athletes need larger muscle mass. The largest average values of BMI were found for males and females in the anaerobic-alactic group.

Reliability of fitness tests using methods and time periods common in sport and occupational management

CONTEXT

Fitness testing is used frequently in many areas of physical activity, but the reliability of these measurements under real-world, practical conditions is unknown.

OBJECTIVE

To evaluate the reliability of specific fitness tests using the methods and time periods used in the context of real-world sport and occupational management.

DESIGN

Cohort study.

SETTING

Eighteen different Cirque du Soleil shows.

PATIENTS OR OTHER PARTICIPANTS

Cirque du Soleil physical performers who completed 4 consecutive tests (6-month intervals) and were free of injury or illness at each session (n = 238 of 701 physical performers).

INTERVENTION(S)

Performers completed 6 fitness tests on each assessment date: dynamic balance, Harvard step test, handgrip, vertical jump, pull-ups, and 60-second jump test.

MAIN OUTCOME MEASURE(S)

We calculated the intraclass coefficient (ICC) and limits of agreement between baseline and each time point and the ICC over all 4 time points combined.

RESULTS

Reliability was acceptable (ICC > 0.6) over an 18-month time period for all pairwise comparisons and all time points together for the handgrip, vertical jump, and pull-up assessments. The Harvard step test and 60-second jump test had poor reliability (ICC < 0.6) between baseline and other time points. When we excluded the baseline data and calculated the ICC for 6-month, 12-month, and 18-month time points, both the Harvard step test and 60-second jump test demonstrated acceptable reliability. Dynamic balance was unreliable in all contexts. Limit-of-agreement analysis demonstrated considerable intraindividual variability for some tests and a learning effect by administrators on others.

CONCLUSIONS

Five of the 6 tests in this battery had acceptable reliability over an 18-month time frame, but the values for certain individuals may vary considerably from time to time for some tests. Specific tests may require a learning period for administrators.

Maximal aerobic power characteristics of male professional soccer players, 1989-2012

PURPOSE

The purpose of this investigation was to quantify maximal aerobic power (VO2max) in soccer as a function of performance level, position, age, and time of season. In addition, the authors examined the evolution of VO2max among professional players over a 23-y period.

METHODS

1545 male soccer players (22 ± 4 y, 76 ± 8 kg, 181 ± 6 cm) were tested for VO2max at the Norwegian Olympic Training Center between 1989 and 2012.

RESULTS

No differences in VO2max were observed among national-team players, 1st- and 2nd-division players, and juniors. Midfielders had higher VO2max than defenders, forwards, and goalkeepers (P < .05). Players <18 y of age had ~3% higher VO2max than 23- to 26-y-old players (P = .016). The players had 1.6% and 2.1% lower VO2max during off-season than preseason (P = .046) and in season (P = .021), respectively. Relative to body mass, VO2max among the professional players in this study has not improved over time. Professional players tested during 2006-2012 actually had 3.2% lower VO2max than those tested from 2000 to 2006 (P = .001).

CONCLUSIONS

This study provides effect-magnitude estimates for the influence of performance level, player position, age, and season time on VO2max in men's elite soccer. The findings from a robust data set indicate that VO2max values ~62-64 mL · kg-1 · min-1 fulfill the demands for aerobic capacity in men's professional soccer and that VO2max is not a clearly distinguishing variable separating players of different standards.

Coordination of soccer players during preseason training

This study aimed to verify whether coordination improves as a result of a preseason soccer training. During 5 experimental sessions (days 1, 6, 11, 15, and 19), 16 semiprofessional male soccer players (22.0 ± 3.6 years) were administered 3 specific soccer tests (speed dribbling, shooting a dead ball, and shooting from a pass) and an interlimb coordination test (total duration of a trial: 60 seconds), consisting of isodirectional and nonisodirectional synchronized (1:1 ratio) hand and foot flexions and extensions at an increasing velocity of execution (80, 120, and 180 b·min(-1)). Furthermore, subjective ratings were monitored to assess the recovery state (RestQ) of the players, their perceived exertion (rating of perceived exertion [RPE]) for the whole body, and the perceived muscle pain (rating of muscle pain [RMP]) for the lower limbs and the internal training load by means of the session-RPE method. The ratios between post and pretraining RPE and RMP increased only during the first 2 experimental sessions and decreased after the second week of the training camp (p = 0.001). The Rest-Q showed increases (p < 0.05) for general stress, conflict/pressure, social recovery, and being in shape dimensions. Conversely, decreases (p < 0.05) were observed for social stress, fatigue, physical complaints dimensions. Throughout the preseason, the players improved their speed dribbling (p = 0.03), Shooting from a Pass (p = 0.02), and interlimb coordination (p < 0.0001) performances. These coordination tests succeeded in discriminating coordination in soccer players and could integrate field test batteries during the whole soccer season, because they were easily and inexpensively administrable by coaches.