Comparison of In-game External Load Metrics Among Positions and Between Halves for Division I Collegiate Women’s Lacrosse Athletes

Abstract

External load has become a common metric for coaches to track the activity profiles of athletes during training and competition. The advent of wearable technology has made external load monitoring accessible for more coaches. The purpose of this study was to compare positional (attack, midfield, and defense) and game (first half to second) external loads. An NCAA Division I women’s lacrosse team was recruited to wear triaxal accelerometers and GPS units during five non-conference games during the 2020 regular season. The external load metrics evaluated for this study included total distance, sprint distance (> 19 km∙hr-1), number of power plays (> 3 m·s-2), top speed, and PlayerLoad. Significance was set at p < 0.05. No significant differences among positions were observed for full game measures (p > 0.05). A significant main effect for time was observed for sprint distance (midfield; p < 0.001 ) and power plays (midfield; p < 0.001 and defense; p = 0.004). While no significant differences occurred for activity profiles among positions, high-intensity efforts (sprint distance and power plays) were significantly less in the second half, likely due to fatigue. Coaches and sports scientists can use this information to manage in-game fatigue through tactics such as strategic substitutions and time-outs, thus preserving the intensity of the activity profiles late in the game.

Athlete External Loads Across a Collegiate Men's Lacrosse Season

“…The arbitrary GPS thresholds commonly used by each respective proprietary software system highlights a limitation of load monitoring, especially when trying to make associations across studies. Player load (255 6 80 AU) also seems lower than previously reported in women lacrosse (;396 AU) (10) and professional men (;379 AU) lacrosse athletes (15). The differences in loads may be attributed to differences in level and style of play, and game rules.…”

“…However, these positional differences are less clear across women lacrosse athletes. For example, several studies have shown no difference in TD, SD, accelerations, and sprints across positions (3,6,10) in NCAA D I players. Furthermore, Hauer et al (2021) found defenders covered the greatest TD and distance at high intensities in international players.…”

Differences across Playing Levels for Match-Play Physical Demands in Women’s Professional and Collegiate Soccer: A Narrative Review

“…Similar to women’s soccer studies published in 2012–2016 [ 25 , 30 ], a study conducted with NCAA DI women’s lacrosse athletes found significant decreases in sprint distance and number of Power Plays (a type of explosive effort derived from PlayerTek technology) from first half of the match to second half of the match [ 44 ]. The data from the DI lacrosse study demonstrated that only midfielders had a significant decline in sprint distance with both midfielders and defenders significantly decreasing the number of Power Plays from the first half to the second half of match-play, indicating a connection between physiological fatigue and the ability to express peak fitness capabilities [ 44 ]. A similar study should be conducted with women’s soccer to determine what trends are evident from first to second half to further inform decision making and program design by women’s soccer coaches.…”

“…Player Load, number of sprints, and sprint distance have all been shown to decrease from the first half to the second half of match-play [ 1 , 25 , 30 , 34 , 44 ], and further research is warranted to determine if this is due to fatigue levels, in which case fatigue could be managed differently to alter the outcome, or if this is due to number of goals scored, competition level, or tactical strategies used (all variables that have not been assessed in the available literature). With further research to increase understanding of why a decrease in external load variables is seen from first half to second half of the match, training programs and coaching strategies can be altered accordingly.…”

“…For example, if team data reveal that midfielders run significantly longer distances than forwards and defenders, as found from team-specific data for females [ 25 , 26 , 31 ] and for males [ 1 ], midfielders may need altered or more aggressive recovery strategies due to higher volumes (longer distances covered) during match-play, as well as higher training volumes during pre-season training in order to adequately prepare for the competitive season’s expected volume. Similar training decisions can be made if total distance, sprint distance or number of sprints in the second half is unexpectedly low compared to the first half, or lower during the Sunday game compared to the Friday game as found in available data [ 1 , 25 , 30 , 44 ]. Additionally, if team-specific data reveal forwards run significantly faster top speeds compared to midfielders and defenders, coaches may consider that forwards should be completing more speed-specific training during off-season and pre-season in order to fulfill their role optimally during the competitive season.…”