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Female Soccer: Part 1—A Needs Analysis

Turner, Ellena BSc (Hons); Munro, Allan G. BSc (Hons); Comfort, Paul MSc, CSCS*D

Strength and Conditioning Journal: February 2013 - Volume 35 - Issue 1 - p 51–57
doi: 10.1519/SSC.0b013e318281f689
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SUMMARY IT IS IMPERATIVE FOR STRENGTH AND CONDITIONING COACHES TO CONDUCT A DETAILED ANALYSIS OF THE DEMANDS OF A SPORT, IDENTIFYING NORMATIVE DATA WHERE POSSIBLE TO PERMIT AN EVIDENCE-BASED EVALUATION OF AN ATHLETE’S CURRENT PERFORMANCE STATUS AND TO INFORM THE DEVELOPMENT OF SPECIFIC GOALS FOR THE ATHLETES’ DEVELOPMENT. PART ONE OF THIS ARTICLE REVIEWS THE DEMANDS OF FEMALE SOCCER AND PROVIDES NORMATIVE DATA FROM PUBLISHED RESEARCH IDENTIFYING SPECIFIC AREAS THAT REQUIRE DEVELOPMENT IN FEMALE SOCCER PLAYERS. PART TWO RECOMMENDS EVIDENCE-BASED APPROACHES INTEGRATED TO ATHLETE DEVELOPMENT AND INJURY PREVENTION STRATEGIES, AS A RESULT OF THE NEEDS ANALYSIS.

Directorate of Sport Exercise and Physiotherapy, University of Salford, Salford, United Kingdom

Conflicts of Interest and Source of Funding: The authors report no conflicts of interest and no source of funding.

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Ellena Turneris a sports scientist at Manchester City FC Academy and a doctoral candidate at the University of Salford.

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Allan G. Munrois a clinical director at Sports Rehab UK, lecturer at the University of Derby, and a doctoral candidate at the University of Salford.

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Paul Comfortis the program leader for the MSc Strength and Conditioning at the University of Salford.

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INTRODUCTION

The published data currently available relating to female soccer demonstrates that a high level of aerobic conditioning is required during a match with average heart rates of 84–86% maximum heart rate (MHR) (4,39) and an average of 9.1–11.9 km total distance covered (3,4,21,30,37,39,49,51). These athletes have also demonstrated a good level of aerobic conditioning (V[Combining Dot Above]O2max: 46–57.6 mL·kg−1·min−1) (25,48,79), although increases are likely to result in increases in match performance (25,32,48). Performance in soccer is primarily associated with a player’s aerobic endurance (5–10,50), which permits the athletes to perform multiple high-intensity efforts. The outcomes of crucial moments in a soccer match depend on the performance of anaerobic activities such as sprinting and jumping (5,36,42,44).

Soccer matches consist of 250 brief intense anaerobic actions, per player, with repeated sprints occurring 39 times, sprinting every 90 seconds, each lasting 2–4 seconds (9,47,48,50,60,67). Sprinting speed is a key aspect within the sport contributing to soccer performance aspects such as obtaining possession and scoring or conceding goals (60). Total distance during sprinting can account for 1,025 ± 150 m accounting 1.4–3% of the game duration (2,21,50). Further intense actions include an average of 111 on the ball activities, jumping, and changing direction 90–100 times at a 90–180° angle (13). These decisive soccer components (striking the ball, turning, jumping, maximum strength, changing pace, cutting, and accelerating and decelerating the body) are forceful and explosive and require near-maximum levels of muscular strength and power production (16,22,35,43,67).

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INJURY RISKS

Even though female soccer is one of the fastest growing sports in the world, the literature within female soccer is fairly limited (3,4,21,30,37,39,49,51). Male soccer players possess greater relative strength, power, speed, and match-specific components than female players. Research regarding landing mechanics suggests that female soccer players may lack strength, conditioning, and appropriate neuromuscular control (19,49,66).

Agel et al. (1) identified female athletes to be at a significantly greater risk of sustaining an anterior cruciate ligament (ACL) injury. Reports have stated that 0.33 ACL injuries per 1,000 hours occur within female soccer players, which is a significantly higher rate than male player’s data (0.11 per 1,000 hours) (1). The fact that women are consistently shown to have significantly reduced neuromuscular control leading to greater knee valgus, combined with lower hamstring strength, may in part explain this increase in ACL injury risk compared with men (23,27,28,52). The majority of ACL injuries are associated with valgus movement combined with anterior tibial shear forces during rapid deceleration-type movements such as landing and changing direction (12,26–28,45,70). Other biomechanical, strength, and neuromuscular aspects have been suggested to contribute to these gender differences including decreased hip and knee flexion during landing and lower hamstrings: quadriceps strength ratio for women (15,29,81). These factors combined with poor conditioning and the number of deceleration activities performed during a soccer match and pitch-based training make female soccer a high-risk sport.

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ANAEROBIC QUALITIES: STRENGTH, POWER, SPEED, AND AGILITY

A soccer player’s absolute strength is beneficial for moving external objects (the ball and opposition players), whereas relative strength is suggested to be more applicable for controlling their own body weight through acceleration and deceleration (78), the latter of which can reach forces of 1.65–4.22 times body mass (11,63,71). It is suggested that a greater maximum lower limb relative strength may improve an individual’s ability to control his/her body during acceleration and deceleration such as sprinting and turning (33,46,77), thus suggesting that a greater relative strength may provide a greater acceleration, acceptance of the high forces, and reduce risks to injury (33,46,77) along with appropriate mechanics. Research also identifies that peak ground reaction forces and impulse (rather than contact time or leg speed) are strong determinants of sprint performance (34,72–76,80).

The normative research data for female soccer players range from 21.0 to 53.1 and 28.9 to 35 cm for countermovement jump height with and without arm swing, respectively (39,40,53,55–57,64) (Table 1). The majority of these scores are less than male soccer data apart from the National Collegiate athletic Association Division I female scores (46.87–56.4 versus 53.1 cm) (14,41,48,55,77,79), illustrating a lack of strength and power in female soccer players. When compared with the male soccer sprint data, US high school female players matched or had a faster 20 m sprint time (3.00–3.12 versus 3.00 seconds) (25,54,65,69,77,79). However, additional female sprint data (Table 2) is slower than the male soccer player’s sprint performances for 20, 30, and 40 m, respectively (3.31 versus 3.00–3.12, 5.06 versus 4.00–4.22, and 5.80 versus 5.35–5.55 seconds) (18,22,25,54,65,69,77,79). This may be partly explained by the lower maximum leg strength data for female soccer players, in terms of both absolute and relative strength performances, when compared with male soccer player’s scores (absolute, 65.7–97.5 versus 105–220 kg; relative, 1.00–1.51 versus 1.77–2.95 kg/kg) (16,40,48,53,55,61,77,79) (Table 3).

Table 1

Table 1

Table 2

Table 2

Table 3

Table 3

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AEROBIC CAPACITY

Female soccer players demonstrate well-developed V[Combining Dot Above]O2max levels (46–57.6 mL·kg−1·min−1), although these are lower than their male counterparts (58.4–63.4 mL·kg−1·min−1) (25,48,79) (Table 4). Research using the Yo-Yo intermittent recovery test found that elite women from the top Danish league achieve greater distances than male soccer players (1,213 vs. 591–1,023 m, respectively) (38,39,62,68) (Table 4). The Yo-Yo intermittent recovery test determines a player’s ability to recover from and repeatedly perform high-intensity exercise (8,38). This soccer-specific test reflects the moments and physiological work rate of a soccer game and significantly correlates (r = 0.81) with match-specific measurements such as high-intensity running distance (34). In general, it is suggested that the aerobic fitness levels of female soccer players should be developed to the highest levels because of the demands of the 90 minutes of competition. A higher level of aerobic conditioning is likely to result in greater distances covered on the pitch, including high-intensity decisive actions (25,31,32,48).

Table 4

Table 4

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MATCH PERFORMANCE

A high level of conditioning is important in soccer for scoring or preventing goals from being scored, where players must be faster and more powerful than the opponent (16). Although no studies directly investigate whether a relationship exists between the conditioning of players and match performance, research has indicated that higher standard players cover greater high intensity (2.43 ± 0.14 versus 1.90 ± 0.10 km and 1.68 ± 0.09 versus 1.30 ± 0.10 km), sprint distance (0.65 ± 0.06 versus 0.41 ± 0.03 km and 0.46 ± 0.02 versus 0.38 ± 0.05 km), and the number of sprint bouts (39 ± 2 versus 26 ± 1 and 30 ± 2 versus 26 ± 1) than lower level players (49,50). Moreover, Rampinini et al. (59) found the top 5 finishing teams in Italian Serie A league demonstrated significantly greater (p < 0.01) total distance, high-intensity distance, ball involvements, and successful passes, tackles, and shots than the bottom 5 teams. Findings by Wisloff et al. (78) support this assumption demonstrating that the top team in Norwegian Elite League possessed greater V[Combining Dot Above]O2max than the bottom league team (67.6 ± 4.0 vs. 59.9 ± 4.1 mL·kg−1·min−1). However, no comparisons of time-motion analysis or match performance were made. Thus, even though studies may collectively indicate players’ level of conditioning links to match performance, success, and level of play they reach, further individual research is required to directly investigate this relationship.

In light of the match characteristics of the sport, it is essential that these athletes have highly developed aerobic energy systems, to cope with the total distance covered, recovery between high-intensity bouts, and the duration of the game. It is also imperative that their anaerobic systems are highly developed to permit optimal performances in the high-intensity acceleration, deceleration, and changes in direction required throughout the game.

Match performance research has demonstrated that female soccer players cover a total distance of 8.6–11.3 km at an average of 85–87% of MHR (3,4,21,25,30,37,39,50,58) (Table 5). During this time, sprinting accounts for a total distance of 0.41–0.65 km and high-intensity distance 1.90–2.43 km, highlighting that female soccer players need to have not only a high level of aerobic conditioning but also the strength and power qualities to permit the performance of multiple high-intensity activities (4,49,50) (Table 5).

Table 5

Table 5

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CONCLUSIONS

Female soccer players lack optimal conditioning both aerobically and anaerobically when compared with men and this may impact soccer-specific performances. Although this has not been investigated thoroughly, it may be suggested that the lack of conditioning may contribute to reduced performance levels in match-specific variables, based on the demands of the sport. The key areas of attention for female soccer players involve both anaerobic qualities (relative strength and power, speed, and agility) and aerobic capacity. By focusing on improving these areas, improvements in anaerobic areas such as relative strength, especially from unilateral training, and plyometric drills may increase lower limb control and the ability to cope with the high forces and velocity movements involved in a match, thereby reducing the risk of injury via improved neuromuscular conditioning. In addition, such improvements are also likely to improve soccer performance in both laboratory- and field-based assessments (sprinting, jumping) and more importantly during matches (methods to improve performance in these areas and how these can be periodized are discussed in part 2).

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Keywords:

injury risk; strength; power; match performance; aerobic endurance

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