Environmental Conditions, Preseason Fitness Levels, and Game Workload: Analysis of a Female NCAA DI National Championship Soccer Season

Influence of match status and possession status on the physical and technical characteristics of elite youth female soccer match-play

This study compared the influence of match status (drawing, losing, or winning) and possession status (in-possession, out-of-possession, or ball-out-of-play) on the physical and technical characteristics of U14 and U16 elite youth female soccer match-play. Data were collected from 189 female academy players during 45 competitive matches, resulting in 387 match observations. Linear mixed models estimated relative; total distance, high-speed running (≥3.00 m·s-1), very high-speed running (≥4.83 m·s-1), and sprinting (≥5.76 m·s-1) distance according to match status and possession status, and 21 technical variables according to match status. Differences in physical and technical characteristics were observed between and within age-groups, dependent upon match status and possession status. Regardless of match status, both age-groups covered greater distances when the ball was in-play compared to ball-out-of-play (107-130 vs 58-68 m·min-1). U16s covered greater distances when out-of-possession than in-possession, regardless of match status. Whilst U14s covered greater distances out-of-possession when drawing or losing only. Differences in physical and technical characteristics when drawing, losing, or winning, suggest a change in playing style according to match status, likely in an attempt to influence or maintain the score-line. These findings have practical implications for coaching, talent identification and development practices within youth female soccer.

Wearables for Measuring Health Effects of Climate Change-Induced Weather Extremes: Scoping Review

BACKGROUND

Although climate change is one of the biggest global health threats, individual-level and short-term data on direct exposure and health impacts are still scarce. Wearable electronic devices (wearables) present a potential solution to this research gap. Wearables have become widely accepted in various areas of health research for ecological momentary assessment, and some studies have used wearables in the field of climate change and health. However, these studies vary in study design, demographics, and outcome variables, and existing research has not been mapped.

OBJECTIVE

In this review, we aimed to map existing research on wearables used to detect direct health impacts and individual exposure during climate change-induced weather extremes, such as heat waves or wildfires.

METHODS

We conducted a scoping review according to the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) framework and systematically searched 6 databases (PubMed [MEDLINE], IEEE Xplore, CINAHL [EBSCOhost], WoS, Scopus, Ovid [MEDLINE], and Google Scholar). The search yielded 1871 results. Abstracts and full texts were screened by 2 reviewers (MK and IM) independently using the inclusion and exclusion criteria. The inclusion criteria comprised studies published since 2010 that used off-the-shelf wearables that were neither invasive nor obtrusive to the user in the setting of climate change-related weather extremes. Data were charted using a structured form, and the study outcomes were narratively synthesized.

RESULTS

The review included 55,284 study participants using wearables in 53 studies. Most studies were conducted in upper-middle-income and high-income countries (50/53, 94%) in urban environments (25/53, 47%) or in a climatic chamber (19/53, 36%) and assessed the health effects of heat exposure (52/53, 98%). The majority reported adverse health effects of heat exposure on sleep, physical activity, and heart rate. The remaining studies assessed occupational heat stress or compared individual- and area-level heat exposure. In total, 26% (14/53) of studies determined that all examined wearables were valid and reliable for measuring health parameters during heat exposure when compared with standard methods.

CONCLUSIONS

Wearables have been used successfully in large-scale research to measure the health implications of climate change-related weather extremes. More research is needed in low-income countries and vulnerable populations with pre-existing conditions. In addition, further research could focus on the health impacts of other climate change-related conditions and the effectiveness of adaptation measures at the individual level to such weather extremes.

A systematic review of match-play characteristics in women's soccer

This review aimed to (1) systematically review the scientific literature evaluating the match-play characteristics of women's soccer, (2) determine the methods adopted to quantify match-play characteristics of women's soccer, and (3) present the physical, technical and tactical characteristics of women's soccer match-play across age-groups, playing standards and playing positions. A systematic search of electronic databases was conducted in May 2021; keywords relating to the population, soccer and match-play characteristics were used. Studies which quantified physical, technical or tactical performance of women's soccer players during match-play were included. Excluded studies included adapted match-play formats and training studies. Sixty-nine studies met the eligibility criteria. Studies predominantly quantified match-play characteristics of senior international (n = 27) and domestic (n = 30) women's soccer match-play, with only seven studies reporting youth match-play characteristics. Physical (n = 47), technical (n = 26) and tactical characteristics (n = 2) were reported as whole-match (n = 65), half-match (n = 21), segmental (n = 17) or peak (n = 8) characteristics. Beyond age-groups, playing standard, and playing position, fourteen studies quantified the impact of contextual factors, such as environment or match outcome, on match-play characteristics. Distance was the most commonly reported variable (n = 43), as outfield women's soccer players covered a total distance of 5480-11160 m during match-play. This systematic review highlights that physical match-performance increases between age-groups and playing standards, and differs between playing positions. However, further research is warranted to understand potential differences in technical and tactical match-performance. Coaches and practitioners can use the evidence presented within this review to inform population-specific practices, however, they should be mindful of important methodological limitations within the literature (e.g. inconsistent velocity and acceleration/deceleration thresholds). Future research should attempt to integrate physical, technical and tactical characteristics as opposed to quantifying characteristics in isolation, to gain a deeper and more holistic insight into match-performance.

Current and Future Trends in Strength and Conditioning for Female Athletes

Participation by female athletes in competitive sport has increased dramatically since the inception of Title IX, although female athletes are represented significantly less than their male counterparts in strength and conditioning (S&C) literature. This is apparent when examining current identified trends in the field, such as implementation of blood flow restriction (BFR) training, functional assessments to predict injuries, or the ever-increasing use of technology in sports. The aim of this review is to examine three prevalent trends in contemporary S&C literature as they relate to female athletes in order to expose areas lacking in research. We conducted journal and database searches to progressively deepen our examination of available research, starting first with broad emerging themes within S&C, followed next by an inquiry into literature concerning S&C practices in females, ending finally with a review of emerging topics concerning female athletes. To this end, 534 articles were reviewed from PubMed, Academic Search Complete, Google Scholar, CINAHL, MEDLINE, and Web of Science. Results demonstrate the utility of implementing BFR, functional movement assessments, and various technologies among this population to expand representation of female athletes in S&C literature, improve athletic capabilities and performance, and decrease potential for injury over time.

The Impact of Environmental Conditions on Player Loads During Preseason Training Sessions in Women's Soccer Athletes

ABSTRACT

Austin, AB, Collins, SM, Huggins, RA, Smith, BA, and Bowman, TG. The impact of environmental conditions on player loads during preseason training sessions in women's soccer athletes. J Strength Cond Res 35(10): 2775-2782, 2021-Our objective was to determine the impact of environmental conditions on player loads during preseason training sessions in women's soccer athletes. Eleven women's NCAA Division III soccer players (age = 20 ± 1 year, height = 167.28 ± 8.65 cm, body mass = 60.18 ± 5.42 kg, V̇o2max = 43.70 ± 3.95 ml·kg-1·min-1) volunteered to wear Global Positioning System (GPS) devices (Sports Performance Tracking, Melbourne, Australia) that provided measures of training session external intensity throughout all preseason practices (n = 15). We recorded wet-bulb globe temperature (WBGT), session Rating of Perceived Exertion-Training Load (sRPE-TL), and ΔBM during each preseason training session and set α ≤ 0.05. The combination of WBGT, sRPE-TL, and ΔBM explained 34% of the variance in GPS-based intensity score (proprietary measure) (F3,153 = 26.25, p < 0.001). Wet-bulb globe temperature (t156 = -2.58, p = 0.01), sRPE (t156 = 8.24, p < 0.001), and ΔBM (t156 = 2.39, p = 0.02) were significantly associated with intensity. The ΔBM from prepractice (60.00 ± 5.21 kg) to postpractice (59.61 ± 5.10 kg) was statistically significant (p < 0.001); however, ΔBM from the beginning of preseason (59.87 ± 5.31 kg) to the end of preseason (59.91 ± 5.58 kg) was not significant (p = 0.89). Despite relatively low to moderate environmental conditions, increases in WBGT were associated with reductions in GPS intensity and elevated internal load via sRPE-TL. Our findings support the association between exercise intensity and WBGT, internal load, and hydration status; thus, coaches and exercise scientists should take these factors into account when monitoring or interpreting intensity metrics. Furthermore, these findings support the continued use of environmental monitoring and hydration best-practice policies to limit exercise intensity in the heat so as to mitigate excessive heat stress.

Physiological Characteristics of Female Soccer Players and Health and Performance Considerations: A Narrative Review

Female soccer has seen a substantial rise in participation, as well as increased financial support from governing bodies over the last decade. Thus, there is an onus on researchers and medical departments to develop a better understanding of the physical characteristics and demands, and the health and performance needs of female soccer players. In this review, we discuss the current research, as well as the knowledge gaps, of six major topics: physical demands, talent identification, body composition, injury risk and prevention, health and nutrition. Data on female talent identification are scarce, and future studies need to elucidate the influence of relative age and maturation selection across age groups. Regarding the physical demands, more research is needed on the pattern of high-intensity sprinting during matches and the contribution of soccer-specific movements. Injuries are not uncommon in female soccer players, but targeting intrinsically modifiable factors with injury prevention programmes can reduce injury rates. The anthropometric and physical characteristics of female players are heterogeneous and setting specific targets should be discouraged in youth and sub-elite players. Menstrual cycle phase may influence performance and injury risk; however, there are few studies in soccer players. Nutrition plays a critical role in health and performance and ensuring adequate energy intake remains a priority. Despite recent progress, there is considerably less research in female than male soccer players. Many gaps in our understanding of how best to develop and manage the health and performance of female soccer players remain.

Effects of Field Position on Fluid Balance and Electrolyte Losses in Collegiate Women's Soccer Players

Background and objectives: Research investigating hydration strategies specialized for women’s soccer players is limited, despite the growth in the sport. The purpose of this study was to determine the effects of fluid balance and electrolyte losses in collegiate women’s soccer players. Materials and Methods: Eighteen NCAA Division I women’s soccer players were recruited (age: 19.2 ± 1.0 yr; weight: 68.5 ± 9.0 kg, and height: 168.4 ± 6.7 cm; mean ± SD), including: 3 forwards (FW), 7 mid-fielders (MD), 5 defenders (DF), and 3 goalkeepers (GK). Players practiced outdoor during spring off-season training camp for a total 14 practices (WBGT: 18.3 ± 3.1 °C). The main outcome measures included body mass change (BMC), sweat rate, urine and sweat electrolyte concentrations, and fluid intake. Results: Results were analyzed for comparison between low (LOW; 16.2 ± 2.6° C, n = 7) and moderate risk environments for hyperthermia (MOD; 20.5 ± 1.5 °C, n = 7) as well as by field position. The majority (54%) of players were in a hypohydrated state prior to practice. Overall, 26.7% of players had a %BMC greater than 0%, 71.4% of players had a %BMC less than −2%, and 1.9% of players had a %BMC greater than −2% (all MD position). Mean %BMC and sweat rate in all environmental conditions were −0.4 ± 0.4 kg (−0.5 ± 0.6% body mass) and 1.03 ± 0.21 mg·cm⁻²·min⁻¹, respectively. In the MOD environment, players exhibited a greater sweat rate (1.07 ± 0.22 mg·cm⁻²·min⁻¹) compared to LOW (0.99 ± 0.22 mg·cm⁻²·min⁻¹; p = 0.02). By position, DF had a greater total fluid intake and a lower %BMC compared to FW, MD, and GK (all p < 0.001). FW had a greater sweat sodium (Na+) (51.4 ± 9.8 mmol·L⁻¹), whereas GK had the lowest sweat sodium (Na+) (30.9 ± 3.9 mmol·L⁻¹). Conclusions: Hydration strategies should target pre-practice to ensure players are adequately hydrated. Environments deemed to be of moderate risk of hyperthermia significantly elevated the sweat rate but did not influence fluid intake and hydration status compared to low-risk environments. Given the differences in fluid balance and sweat responses, recommendations should be issued relative to soccer position.