Lacrosse was the fastest growing men's NCAA sport between 2000 and 2014, increasing by 95% from 203 to over 350 teams nationwide. Along with indoor track and field, men's lacrosse has seen the greatest increase in teams since 1988 (33). Empirical and observational evidence suggests men's lacrosse is physically demanding in that it requires both aerobic and anaerobic fitness, strength, power, agility, and mobility along with sport-specific skills (16,36).
Although injury trends in men's lacrosse has been well explored (9), the majority of current research exploring the physiological profile of lacrosse athletes has been conducted on women's lacrosse players (albeit still in limited amounts) (10,21,45). Collins et al. (6) and Gutowski et al. (16) have generated physiological profiles for Division III collegiate male lacrosse players that supported the need for aerobic and anaerobic fitness in lacrosse players, particularly speed endurance, but did not analyze differences in fitness performance scores between starters and nonstarters. Steinhagen et al. (40) showed that first team members of a men's lacrosse club team had above-average aerobic capacity, body composition, and maximal power scores compared with the general population, and aerobic and body composition scores that were comparable with or higher than other intermittent sports. This research also showed first team members (i.e., starters) had higher aerobic fitness, maximal and mean power, and lower percent body fat than second team members (i.e., nonstarters), and that defensemen had higher maximal and mean absolute power, but lower aerobic capacity compared with other positions (40). However, this research involved club lacrosse athletes (as opposed to NCAA student athletes), no statistical analysis other than descriptive data was presented, and was conducted nearly 2 decades before, during which time the physical demands have evolved.
To the best of the authors' knowledge, no research has examined the physical fitness profile of men's NCAA Division I lacrosse players at the conclusion of pre-season, nor have differences across position or starting status in this population been evaluated in previous research. Therefore, in the same manner that previous research on women's collegiate lacrosse players (21) has assisted strength and conditioning coaches in the development of sport-specific training programs, the purpose of this research was to provide a position-specific physiological profile of men's NCAA Division I lacrosse players at the conclusion of pre-season and compare differences across position and starting status. This research may assist strength and conditioning coaches in doing the same for men's lacrosse at the Division I level as previous research has for women's lacrosse in helping strength and conditioning professionals develop sport-specific training goals and subsequent programs for men's lacrosse in preparation for the competitive collegiate season.
Experimental Approach to the Problem
Body composition, aerobic fitness, muscular strength, explosive power, agility, and speed performance measures for an NCAA Division I men's lacrosse team were collected using sport-specific tests to generate a physiological profile specific to these athletes. Comparisons for each fitness test score across defensive, midfield, and attack positions, as well as between starters and nonstarters, were also generated to determine differences that may influence strength and conditioning preferences for specific positions or measures of fitness that best differentiate starting status.
Forty-one male NCAA Division I collegiate lacrosse players (mean ± SD; 19.6 ± 1.6 years [all subjects were 18 years or older]; 182.0 ± 5.4 cm; 82.5 ± 9.5 kg) volunteered to participate in this study. All subjects were members of the men's lacrosse team, injury-free, healthy, and able to complete a battery of fitness tests. Before participation, each subject was informed of the benefits and risks of the study before signing the institutional review board–approved informed consent. Each subject also completed a medical health history questionnaire, and demonstrated that they did not have any health-related contraindications to physical activity. Approval from the Hofstra University Institutional Review Board for use of human subjects in research was sought before study initiation.
All subjects attended an initial consultation (during which time no study data were collected) to complete the informed consent and medical health history questionnaire and ask any questions regarding data collection and protocol. After the initial consultation, subjects participated in a battery of fitness tests spread over a 2-week period toward the end of organized pre-season training (early-mid November). To minimize the impact of pre-season training and practice volume on test performance and obtain a realistic gauge of fitness close to beginning of the competitive season, the following approaches were taken: (a) testing was conducted toward the end of pre-season when all scrimmages and practice games had been completed, (b) each testing session was separated by 48–72 hours (Table 1 for testing schedule) and included a thorough warm-up where necessary, (c) testing was conducted in place of scheduled conditioning sessions between 6:30–8:30 am, and (d) subjects were instructed to attend all sessions in a hydrated state and having consumed a light breakfast consistent with all early morning training session guidelines discussed with their strength and conditioning coach at the beginning of the pre-season. All data collection procedures were supervised and conducted by a certified strength and conditioning specialist and certified exercise physiologist. Testing took place on an indoor AstroTurf field (FieldTurf, Montreal, Quebec, Canada) (similar to the surface on which competitive matches are played) or inside in the weight room in which the athletes conduct their strength and conditioning sessions. During all data collection sessions, each subject was asked to wear appropriate running attire including shorts, t-shirt, and athletic shoes.
Measures: Height and Body Mass
Standard scale and stadiometer (standing measure) (Detecto, Webb City, MO, USA) were used to determine body mass in kilograms and height in centimeters.
Seven-site skinfold (7SKF) measures using a Lange skinfold caliper (Lange, Beta Technology Inc., Cambridge, MD, USA) were used to assess percentage body fat (%BF). Standardized protocols and site identification were followed (1,25) for each of the 7 sites (chest, tricep, subscapular, midaxillary, suprailiac, abdomen, and midthigh). All measurements were taken on the right side of the body in a rotational manner and repeated until duplicate measures within 2 mm were obtained. Average measures at each site were summed to determine body density using regression equations (26). Subsequently, %BF was estimated using the Brozek equation (3). Good-to-excellent validity (R = 0.90) has been demonstrated for skinfold measures in estimating body density in young men compared with hydrostatic weighing (26).
The 1.5-mile run test was used to assess aerobic fitness. Subjects were asked to run 1.5 miles as quickly as possible, and time to completion was recorded in minutes and seconds to the nearest 10th. Research has demonstrated good-to-excellent validity (R = 0.87) for this approach compared with V̇o2max values determined directly by indirect calorimetry (14).
Speed was determined using 20- and 40-yard sprint times. Timing gates (Brower Timing Systems, Draper, UT, USA) were placed at 20 and 40 yards so that both times could be recorded as the subjects ran a 40-yard sprint. Timing began when the subjects began movement from their starting position by a tester standing next to the start line pressing the manual start button for the timing gate system. A 3-point stance starting position was used because this was the stance the subjects had used in practice drills before the study. This sprint was repeated at least 2 times and the best time in seconds (±0.01 seconds) was recorded. Test-retest reliability for the 20- and 40-yard sprints was R > 0.85.
The pro-agility test and 3-cone drill were used to assess agility according to protocols previously presented (43). Both have been used to assess agility in lacrosse players in previous research (10,21). Agility times were determined using handheld stopwatches, and the same researcher conducted each of the tests. For the pro-agility, 3 cones were placed in a straight line on ground markers (lines) 5 yards apart. Each subject began by straddling the middle marker. The test began with a sprint to the left cone (5 yards or 4.5 m away), touching the marker with the hand, and then a change in direction and sprint to the far right cone (10 yards or 9 m away), touching the marker before reversing direction again to sprint through the middle line. The 3-cone test began with the subject in an upright stance sprinting 5 yards (4.5 m) from cone A to cone B, touching the base on cone B, and sprinting back to cone A. Without stopping, the subject then reversed direction again, sprinting around cone B toward cone C (5 yards or 4.5 m away), set 90° from cone B. Subjects circled cone C counterclockwise, sprinting back around the outside corner of cone B, back to cone A (which they were instructed to sprint through the line on which cone A was placed).
For each test, the timer began on the subject's first movement and stopped timing as the subject crossed the finish line, and the fastest time after 3 attempts in each direction was recorded in seconds (±0.01 seconds). Each of the agility tests was repeated in the opposite direction for comparative purposes, similar to previous research (28). For example, the pro-agility test was also conducted with the subjects first turning to the right (pro-agility–right). Test-retest reliability for the pro-agility and 3-cone drill were between R = 0.7–0.86.
Maximal Power and Strength
A 3RM estimate hang clean, squat, and bench press were used to estimate 1RM lower- and upper-body muscular strength. Testing for each lift incorporated a warm-up of 5–10 repetitions at a low-intensity weight (40–60% of perceived maximum) before the assessment. A 3-minute rest was provided between lifting attempts in accordance with established recommendations by the National Strength and Conditioning Association (NSCA) (5). The hang clean, squat, and bench press technique were performed according to previously published approaches (5). The hang clean was performed with the barbell beginning just above the knees. The bar was then lifted rapidly through the first and second pull phases, caught in a quarter-squat position with the arms under the bar, and the bar positioned across the front of the clavicles and anterior deltoids before standing in a fully erect position. The squat was performed with the subjects descending so the top of the thigh was parallel to the floor (approximately, the greater trochanter of the femur was level with the knee), and ascended to full knee extension, maintaining a neutral spine throughout the movement. The bench press was conducted with subjects in the five-point body contact (supine) position using a closed, pronated grip, and a trained spotter. The barbell was lowered to the chest (at approximately the nipple level), followed by full elbow extension. These exercises have been used in previous research to evaluate lower- and upper-body strength involving lacrosse players (10,21).
A handgrip test for each hand was conducted using a Jamar Handgrip Dynamometer (Model J00105; Lafayette Instrument, Lafayette, IN, USA). The dynamometer was adjusted to fit the specific hand size of each individual subject. During the test, each subject was asked to squeeze the handgrip dynamometer as hard as possible for 3 seconds. The measure was repeated 3 times for each hand and the highest value in kilograms was recorded. Test-retest reliability for the handgrip was R = 0.85.
The vertical jump was assessed using the Just Jump Mat (Probotics Inc., Huntsville, AL, USA) to measure explosive power. Each subject stood on the mat and performed a countermovement jump with backward arm swing, in which they were asked to jump as high as possible and land softly in the same spot on the mat. The best of 3 attempts was scored in centimeters to the nearest millimeter. The subjects were instructed to take no steps when attempting to jump. The Just Jump Mat has been shown to have excellent validity (r = 0.97) compared with a 3-camera system criterion (29).
Data were reported as mean values and SDs and analyzed using the IBM SPSS Statistics 22 for Windows (IBM Corp., Armonk, NY, USA). A p value ≤ 0.05 was used as an acceptable level of significance for all analyses. Nonparametric statistics (Kruskal-Wallis and Mann-Whitney U tests) were used to analyze differences in anthropometric and fitness assessment outcomes across different positions and starting status. Goalkeepers (n = 3) were included in the analysis for starters vs. nonstarters, but excluded from the position-specific comparisons due to the small sample of players in that position. Tukey's post hoc tests were used to identify where any significant differences presented, if necessary. Magnitude-based inferences (MBIs) were also used to identify the presence of practical differences for each variable across different positions and starting status. This approach has been used in several studies (15,31) similar to the current study to reduce interpretation error when using small and uneven sample sizes (22). Microsoft Excel (Microsoft Corp, Redmond, WA, USA) was used to set the precision of the MBI at 95% confidence intervals using a p value ≤ 0.05. This value in addition to the minimal difference threshold value (20% of the grand mean) and the degrees of freedom were entered into a published effect statistics calculator (2) for interpretation. Qualitative inferences on group differences for position and starting status were determined as positive, trivial, or negative based on the range of confidence interval relative to the value for the smallest clinical worthwhile effect. The outcome is determined as unclear if the likely range overlaps both the positive and negative values markedly. The chance that the effect was positive or negative was evaluated by the following scale: <1%, almost certainly not; 1–5%, very unlikely; 5–25%, unlikely; 25–75%, possible; 75–95%, likely; 95–99%, very likely; and >99%, almost certain (23). Furthermore, a comprehensive comparison of the fitness scores from the current study was made to the general population and other athletic populations using previously published research.
The descriptive demographic and physical fitness assessment data across starting status and position are presented in Table 2. Starters were significantly faster compared with nonstarters for the 3-cone drill–left (U = 70.0, p = 0.01), and 20- and 40-yard sprints (U = 52.0, p < 0.01 and U = 75.5, p = 0.04, respectively). Starters also jumped significantly higher on the vertical jump (U = 172.0, p = 0.03) compared with nonstarters. Magnitude-based inferences support the nonparametric statistics findings regarding better 3-cone drill, vertical jump, and both 20- and 40-yard sprint performance compared with nonstarters. However, MBIs also indicated that starters may possibly have lower %BF and faster pro-agility completion times than nonstarters. The possibility of differences across starting status for grip strength, 1.5-mile time, and 1RM bench press, hang clean, or squat (absolute and relative) was unclear or unsupported based on the data collected (Table 2).
The descriptive demographic and physical fitness assessment data across positions are presented in Table 3. The only statistically significant difference across positions was found for body mass. Defensive players were significantly heavier than the attackmen (χ2(3) = 10.66, p = 0.014). Magnitude-based inferences support the nonparametric statistics findings regarding differences in body mass across positions, but also suggest that differences may exist between each of the other positions. However, magnitude-based interpretations also highlight possible differences across positions for a multitude of other fitness variables (Table 4). Defensive players likely demonstrated a slower 20-yard sprint time than midfielders, and possibly higher 1RM hang cleans and lower 1RM bench press relative to body mass compared with midfielders. Midfielders were likely to show slower pro-agility times (on the right only) and stronger 1RM bench press performances than players in the attack position. The practical differences for any outcome across positions not presented in Table 4 were inferred as unclear.
The purpose of this study was to build a physical fitness profile for a NCAA Division I men's lacrosse team and to determine whether any fitness performance measures were able to differentiate starters from nonstarters. To the best of authors' knowledge, this is the first study to do so in Division I collegiate men's lacrosse players because previous research has only studied female lacrosse players at this level or men's college club players (6,21,40).
The main finding of this study was that speed, explosive power, and agility scores were significantly better in starters compared with nonstarters. The speed, agility, and change of direction demands of lacrosse and the need to emphasize these attributes within a sport-specific strength and conditioning program have been previously highlighted (35). In support of this, previous research has suggested that lacrosse-related activity relies 70% on anaerobic pathways and 30% on aerobic pathways to fulfill energy demands (11). However, the difference in explosive power, speed, and agility scores between starters and nonstarters may help players and strength and conditioning coaches design sport-specific training programs. Sprint and agility-based training typically incorporates efforts involving high relative intensities (8), which require an athlete to be able to recover quickly between repetitions to maintain performance outcomes. Specifically, this may be of primary importance during pre-season programming after a foundation of physical conditioning during the off-season and early pre-season has been established.
Previous research has demonstrated a relationship between speed, agility, and explosive power in male rugby players (7) and male soccer players (17). Our findings concerning speed and agility as attributes distinguishing starting status also reflect previous studies involving professional rugby players (13) and collegiate basketball players (25). However, previous studies on anaerobic and intermittent sport athletes have also shown that strength and absolute power may differentiate starting status in collegiate footballers (24,37), rugby players (13), and male volleyball players (32), which was not found in the current study. Aerobic power or maximal aerobic velocity has been found to differentiate starting status in rugby players (13), but was unable to differentiate starting status in the men's lacrosse players in the current study. Vertical jump has been shown to predict selection status in professional football players, specifically National Football League wide receivers selected for the Pro Bowl (All-Pro wide receivers demonstrated higher vertical jump scores than those not selected) (18). However, the ability of vertical jump or other fitness scores to predict selection or starting status on a team has not been consistently demonstrated for sports such as professional or Division I college football (20,27) or professional volleyball (32). The inconsistencies across the aforementioned research may be the result of comparing physical performance scores across different sexes and playing levels (e.g., junior vs. professional, Division I vs. Division III), variable assessment methods (e.g., V̇o2max treadmill test vs. 1-mile run), and differences concerning the time of testing (e.g., pre- vs. in-season). Hoffman et al. (21) and Gabbett (12) have emphasized that research using fitness performance scores to differentiate starting status may also be limited in that it does not account for either preferential recruitment by the coach of specific attributes in a given player that suit the coaching or playing style of the team, or the relative contribution of the athletes' sport-specific skill to the likelihood of being a starter. A coach's perception of an athlete's sport-specific skill may confound the relationship between physical fitness attributes and either starting status or playing time (12,21).
Linear sprint speed is considered essential in positions that must guard opposing players (45); therefore, it is not surprising that this variable was able to distinguish starters from non-starters, or show that midfielders are likely (according to the MBIs) to have faster sprint times than goalkeepers or defenders. The lack of likely differences in sprint, agility, muscular strength, or power performance between defensive and attacking players (other than one 3-cone drill) may be due to the need for both positions to respond to the same changes of direction, explosive, acceleration or deceleration efforts during a given offensive play (45). If a defender is much slower than the attacking player they are guarding, the attacking player will most likely become more open for receiving a pass, whereas a slower attacking player will most like not become open as frequently. However, attacking players were faster than defensive players for the 3-cone drill, whereas defensive players were faster than attacking players for the pro-agility test. Although these differences were not statistically different, MBIs did infer that a likely difference between these positions occurred for the 3-cone drill. This may support the use of different agility drills for distinguishing preparation for playing position, given their different change-of-direction speed, maneuverability, and perceptual-cognitive demands (8). For example, defenders need to guard an attacking player by typically facing the same direction as the player (consistent with the pro-agility test), whereas attacking players may maneuver in any direction in their efforts to evade the guard (consistent with the 3-cone drill).
Defensive players were significantly heavier than attacking players, suggesting that defensive players need to be able to aggressively defend the goal and regain ball control from opposing players (16). Midfielders have been reported as needing the highest level of fitness across all positions, given the stamina (distance and speed) they need to exert during a game (4,16). Although midfielders demonstrated likely higher grip strength, agility, speed, and muscular strength than different positions in the current study, the MBIs overall did not fully support this statement. The lack of statistically significant differences between midfielders and defensive players in the current study may be due to the relatively small sample size at different positions or the result of overlapping positional play. For example, short-stick defensive midfielders who help transition defensive into offensive players similar to a center back or sweeper in soccer are becoming more prevalent in collegiate lacrosse. Further research with a larger sample size may help clarify these findings. However, the small differences at each position may also be explained by the nature of collegiate lacrosse, which involves teams working more as a unit, short rest periods or timeouts, and regular player substitutions depending on the tactical approach in a given game, as has been suggested in previous studies looking at other intermittent sports (30). Vertical jump scores did not differ across positions in the current study, but were significantly higher in starters, possibly suggesting that explosive vertical power is important across all positions.
Lacrosse players require a high degree of stamina to run the length of a lacrosse field (120 yards), as well as recover from short bursts of high-intensity activity throughout the course of a game (4 quarters of 15 minutes each) (44). Previous research has described lacrosse as being similar to soccer in that it requires stamina and a high level of aerobic fitness (4,16); therefore, the 1.5-mile run times (equivalent to approximately 53.0 ml·kg−1·min−1) and similar aerobic fitness levels to men's soccer players (38) are not surprising. However, research has also described lacrosse as being similar to basketball or ice hockey in that it requires explosive, quick movements, and to football with regard to the collision and impact aspects inherent in the sport (16,44). Starters in the current study were generally faster than previously recorded scores for highly anaerobic (e.g., football and baseball) and intermittent sport athletes (e.g., soccer and basketball) (19,20,38,39). Not surprisingly, the players in the current study were weaker than football players (whose overall size and sport should result in greater relative anaerobic power and strength compared with aerobic fitness) (34). However, the current athletes had higher 1RM bench press scores than other intermittent or anaerobic athletes (20,34,46), most likely due to the collision aspect of men's lacrosse that is largely absent in sports such as soccer and baseball.
Thomas et al. (41) has previously shown that improvements in speed, change of direction, agility, and jump performance may occur in national male lacrosse players over a 24-week competitive season. Future studies should expand on the current study and the work of Thomas et al. (41) to follow the changes in physical fitness attributes in starters and nonstarters from pre-season throughout the competitive season to explore whether starting status changes with improvements in speed, agility, or other areas of fitness. Furthermore, the use of different agility drills specific to different positions on a lacrosse team (as well as dominant or nondominant hands) should be explored, given the different movement patterns and maneuvers each position must perform throughout a game.
Training that emphasizes explosive power, speed, and agility may help prepare male lacrosse athletes for the competitive season. However, nonstarters looking to target sport-specific fitness attributes should be aware that optimal training practices for high-level agility and speed-based training require a foundation of aerobic training and muscular strength to decrease fatigue and aid with recovery after anaerobic conditioning (42).
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