Locomotor and technical characteristics of female soccer players training: exploration of differences between competition standards

OBJECTIVES

To (i) quantify the differences in locomotor and technical characteristics between different drill categories in female soccer and (ii) explore the training drill distributions between different standards of competition.

METHODS

Technical (ball touches, ball releases, high-speed ball releases) and locomotor data (total distance, high-speed running distance [>5.29 m∙s^-1]) were collected using foot-mounted inertial measurement units from 458 female soccer players from three Women's Super League (WSL; n = 76 players), eight Women's Championship (WC; n = 217) and eight WSL Academy (WSLA; n = 165) teams over a 28-week period. Data were analysed using general linear mixed effects.

RESULTS

Across all standards, the largest proportion of time was spent in technical (TEC) (WSL = 38%, WC = 28%, WSLA = 29%) and small-sided extensive games (SSGe) (WSL = 20%, WC = 31%, WSLA = 30%) drills. WSL completed more TEC and tactical (TAC) training whilst WC and WSLA players completed more SSGe and possession (POS) drills. Technical drills elicited the highest number of touches, releases and the highest total distance and high-speed activity. Position-specific drills elicited the lowest number of touches and releases and the lowest total distance. When the technical and locomotor demand of each drill were made relative to time, there were limited differences between drills, suggesting drill duration was the main moderating factor.

CONCLUSION

Findings provide novel understanding of the technical and locomotor demands of different drill categories in female soccer. These results can be used by coaches and practitioners to inform training session design.

Comparative properties of tobacco hornworm, Manduca sexta, carbonic anhydrases

Comparative properties of midgut, fat body and integumentary carbonic anhydrases (CAs) were measured as functions of CA-catalyzed CO2 hydration or p-nitrophenylacetate (pNPA) hydrolysis in feeding larvae and pharate pupae. Alkali metal cations fully reverse the halide anion inhibition of CA catalyzed CO2 hydration during the larval but not the pharate pupal stages in development. Concentrations of acetazolamide required to inhibit 50% of tissue-specific CA-catalyzed CO2 hydration (I50) were approximately 10(-8) M. The activity profiles between pH 6.0 and 9.0 had well-defined optima around pH 8.0 with activity declining dramatically above the optima. When CA-catalyzed pNPA hydrolysis was measured between 4 and 37 degrees C, insect enzymes failed to exhibit positive Q10 values between 25 and 37 degrees C. The affinities of the hornworm CAs toward pNPA were determined with stage- and tissue-specific Km ranging from 0.42 to 8.0 X 10(-3) M. It is concluded that tissue and stage-specific CAs exist in M. sexta, whose properties appear to differ markedly with those previously reported for mammalian enzymes.