Female Volleyball Athletes Research Articles

Impact of in-season injury on quality of life and sleep duration in female youth volleyball athletes: a prospective study of 2073 players

ObjectivesThe psychological impacts of injuries in youth athletes remain poorly defined. The purpose of this study was to evaluate the influence of injury on quality of life (QOL) and sleep...

Preferences of Collegiate Volleyball Players Regarding Leadership Style

The purpose of this study was to determine the coaching style preferences of Division II and III female collegiate volleyball athletes. Five hundred and nine female student-athletes from 41 colleges/universities expressed their preferences using the Revised Leadership Scale for Sport (RLSS) (Zhang et al., 1997). The preference version of the RLSS included six behavior dimensions: autocratic, democratic, positive feedback, situational consideration, social support, and training and instruction behaviors. Descriptive statistics were used to determine training and instruction behaviors and situational consideration were the most preferred coaching styles for all athletes. Autocratic was the least preferred coaching style. Independent t tests and ANOVA were used to address whether gender of the coach, athlete’s gender preference of the coach, division of the university, and/or athlete’s year in school affected the coaching style preference. The results showed that across all the independent variables investigated, athletes most preferred training and instruction and situational consideration coaching styles and least preferred the autocratic style. The only difference for any demographic was that athletes with female coaches preferred social support and positive feedback more than athletes with male coaches.

Efficacy of an Educational Intervention for Improving the Hydration Status of Female Collegiate Indoor-Sport Athletes.

Research focusing on improving hydration status and knowledge in female indoor-sport athletes is limited. Investigators have demonstrated that hydration education is an optimal tool for improving the hydration status of athletes. To assess the hydration status and fluid intake of collegiate female indoor-sport athletes before and after a 1-time educational intervention. Controlled laboratory study. Collegiate women's volleyball and basketball practices. A total of 25 female collegiate volleyball and basketball athletes (age = 21 ± 1 years, height = 173.5 ± 8.7 cm, weight = 72.1 ± 10.0 kg) were assessed during 6 days of practices. Participants' hydration status and habits were monitored for 3 practice days before they underwent a hydration educational intervention. Postintervention, participants were observed for 3 more practice days. Change in body mass, fluid consumed, urine specific gravity (Usg), urine color (Ucol), and sweat rate were recorded for 6 practice days. Participants completed a hydration-knowledge questionnaire before and after the intervention. Three-day mean Usg and Ucol were considered euhydrated prepractice (Usg = 1.015 ± 0.006, Ucol = 4 ± 1) and remained euhydrated postpractice (Usg = 1.019 ± 0.005, Ucol = 5 ± 2) during the preintervention period. Decreased prepractice Ucol (P < .01) and increased hydration knowledge (P < .01) were present postintervention. Basketball athletes had greater body mass losses from prepractice to postpractice than did volleyball athletes (P < .001). Overall increases were evident when we compared prepractice and postpractice measures of Usg and Ucol in the preintervention (P < .001 and P = .001, respectively) and postintervention (P = .001 and P < .001) period, respectively. No correlation was found between hydration knowledge and physiological indices of hydration and fluid intake. Overall, female collegiate indoor-sport athletes were hydrated and knowledgeable on hydration. However, our variable findings indicated that further research on these athletes is needed; clinically, attention should be given to the individual needs of each athlete. More examination will demonstrate whether a 1-time educational intervention may be an effective tool for improving hydration status in this population.

Urine Loss during a Volleyball Competition: Comparison between Amateur and Professional Athletes

High-impact sports can cause dysfunction to the female pelvic floor that leads to the occurrence of stress urinary incontinence. To identify and compare the presence of urine loss between professional and amateur female volleyball athletes during a competition. A cross-sectional and comparative study was conducted on 75 volleyball athletes, including 30 amateurs and 45 professional athletes. Female athletes 18 years of age or older were included. Urine loss during the competition was evaluated by self-report and measured by a pad test (in grams). Day-to-day urinary incontinence was identified using the Urinary Distress Inventory 6 (UDI-6). Before the beginning of the game, the instruments were applied by individual interview for data collection and the pad was positioned. After the game, the pad was removed and weighed again. Descriptive and inferential statistics were used, with a significance level of 5%. Half of the professional (50.0%) and amateur (55.6%) athletes have symptoms of urine loss during a competition. Objective urine loss was higher among professional athletes (4.5 ± 1.4g) compared to amateur athletes (3.8 ± 1.4g). There was a significant difference (P < .001) in objective urine loss between symptomatic (mean = 5.41, standard deviation [SD] = 0.8) and asymptomatic professional athletes (mean = 3.40, SD = 1.3). Self-report of urinary incontinence during the competition was common among professional and amateur athletes. However, objective urine loss was significantly higher among professional athletes.

THE USE OF POSTURAL RESTORATION FOR TREATMENT OF CHRONIC ROTATOR CUFF PATHOLOGY: A CASE REPORT.

Postural Restoration Institute® (PRI) theories and rehabilitation techniques focus on restoring balance to anatomical systems. Common postural asymmetries can present in athletes as dysfunctions and limitations. The purpose of this case report was to examine the use of PRI exercises and theories to address pelvic alignment, along with core stabilization, during treatment of shoulder dysfunction in a collegiate volleyball player. A 22-year-old female volleyball athlete reported unresolved right rotator cuff tendinopathy. She presented with bilateral rib cage flare, anterior pelvic tilt, and bilateral ROM differences in hip and shoulder internal and external rotation. PRI® special test findings included a positive left and right Adduction Drop Test (ADT), positive left Extension Drop, and Hruska Adduction Lift test (left=2, right=3) indicating posterior exterior chain (PEC) pattern of dysfunction. The traditional shoulder rehabilitation program from the previous season was eliminated and a PRI based intervention was performed. Intervention exercises included the 90/90 dead bug diaphragmatic breathing, 90/90 hamstring hip lift, and right sidelying respiratory left adductor pull back. Exercises were performed as three sets of ten diaphragmatic breathing repetitions, a minimum of three times weekly prior to activity. Likert scale ratings of pain decreased from a six pre-intervention to two. The left hip gained 10° of internal rotation and the right hip gained 14° of external rotation. Right shoulder internal rotation increased 15°. Hruska Adduction Lift improved to a four bilaterally (right by day 24, and left by day 31). Left extension drop test was negative following day 17. PRI® exercises focusing on core and pelvic stability translated to improved hip and shoulder ROM, and decreased shoulder pain associated with rotator cuff tendinopathy. By treating pelvic alignment with the PRI® exercises, the ROM imbalance and pain at the shoulder joint were addressed. Incorporating PRI exercises and theories into the rehabilitation program of a volleyball player was useful in addressing underlying imbalances throughout the kinetic chain. 3b.

Sport specialization and sport participation opportunities and their association with injury history in female high school volleyball athletes

ObjectiveDetermine the association of sport specialization in female volleyball athletes with previous injury history and determine the association of sport specialization with volleyball participation opportunities. DesignCross-sectional. SettingRecruitment occurred from 83 Wisconsin high schools during the 2018 volleyball season. ParticipantsFemale volleyball athletes (N = 1,588, grades 9–12, age = 15.6 ± 1.1 years). Main outcomesParticipants completed a pre-season questionnaire soliciting information regarding 1) demographics, 2) sport specialization, 3) sport participation, and 4) sport-related injuries in the previous 12 months. Univariable logistic regression models were used to identify associations with previous injury. Chi-square analyses were used to investigate associations between sport specialization classification and other sport participation opportunities. ResultsBoth moderately and highly specialized athletes were more likely to report a previous injury compared to low specialized athletes (moderate OR: 1.84 [1.29–2.62]; p < 0.001 and high OR: 2.30 [1.64–3.24]; p < 0.001). Highly specialized athletes were more likely to report participating in club volleyball, summer tournaments, and training camps in the past 12 months. Participants who reported participating in club volleyball, summer competitions, and training camps last year were more likely to report an injury. ConclusionsSpecialization was associated with injury history and year-round volleyball opportunities among female adolescent volleyball athletes.

Estado de humor em esportes coletivos: estudo de caso das equipes de Itatiba

O estudo teve o objetivo foi investigar os estados de humor de atletas de esportes coletivos, das equipes da cidade de Itatiba/SP, participantes dos jogos regionais de 2018. Assim, foi utilizada a Escala de Humor de Brunel (BRUMS), junto a 34 atletas, voluntários, do ambos os sexos, com idades entre 15 e 29 anos. Os participantes pertenciam a 3 equipes: Voleibol Masculino, Voleibol Feminino e Basquetebol Masculino. Os resultados demonstraram que no início da competição os atletas de todas as equipes apresentavam estado de humor positivo, já que o fator Vigor obteve os maiores escores, mas as atletas do Voleibol Feminino foram superiores nesse fator as demais equipes. Pode-se concluir que os atletas investigados apresentaram escores superiores ao fator Vigor, caracterizando a amostra com o perfil denominado de iceberg, perfil considerado ideal para o rendimento esportivo.

PREVALENCE OF OVER THE COUNTER PAIN MEDICATION USE AMONG HIGH SCHOOL VOLLEYBALL PLAYERS

Background:Volleyball’s popularity among middle and high school girls continues to rise with many athletes playing the sport year-round. While up to 40% of high school basketball players consume analgesics frequently to manage sport related pain, there is limited evidence regarding the prevalence of over the counter (OTC) pain medicine use among high school volleyball players.Hypothesis/Purpose:Identify the prevalence of OTC pain medicine use in high school volleyball players and assess its association with prior injury and sports specialization level.Methods:Female volleyball players from 78 high schools were recruited to enroll in this prospective cohort study during the fall 2018 volleyball season. Baseline data were collected on demographic and volleyball characteristics including volume and type of volleyball participation, sport-related injuries over the previous twelve months, and level of sport specialization. The frequency of OTC pain medication use for pain management not related to menstrual cramps over the previous seven days was also collected. Participants were asked to describe their OTC pain medicine use during practice, matches, or conditioning and the location of pain they were treating.Results:In total, 2,073 female athletes (Age: 15.6 ± 1.1, BMI: 22.4 ± 3.5, Grade: 9-12) enrolled in the study. Sixty-nine percent (n=1425) reported no OTC pain medication use over the past seven days, 16.0% (n=332) reported seldom (one day/week) OTC medication use, 12.6% (n=261) reported sometimes (2-3 days/week) using OTC medications, and 2.7% (n=55) reported frequent (4-5 days/week) OTC medication use. In the same time period, 24.8% (n=513) used OTC medications during practice, 16.0% (n=331) during matches, and 21.4% (n=443) during conditioning. Across practice, matches, and conditioning OTC medications were most frequently used to control headaches (7-13%) and knee pain (4-6%). Highly specialized volleyball players were more likely to frequently use OTC medications (4.5%) compared to low (1.97%) and moderately specialized (2.5%) athletes (p=0.001). Of those reporting no OTC medications use, 16.7% (n=238) had an injury in the last year compared 36.4% (n=20) of athletes who frequently used OTC medications also reporting an injury in the last year (p<0.001).Conclusion:Almost one third of female high school volleyball athletes reported using OTC pain medications in the past week. Those with a history of injury and highly specialized athletes were more likely to use OTC medications. Coaches, athletic trainers, and healthcare providers should be aware of trends in the use of OTC medications among volleyball athletes as its popularity continues to rise.

Voice Characteristics of Female College Athletes: A Pilot Study

Purpose The purpose of this study was to identify changes in NCAA Division II female athletes' objective and subjective voice characteristics before, during, and after a regular volleyball season. Method Acoustic, aerodynamic, and Voice Handicap Index-10 data were collected from five female volleyball athletes at three timepoints: preseason, midseason, and postseason. Results Individual data suggest increases in objective and subjective voice characteristics at midseason, but many values returned to typical limits at postseason. Increases observed in acoustic, aerodynamic, and Voice Handicap Index-10 data for the volleyball team captain remained elevated at midseason and postseason. Conclusions Female volleyball players are a group of voice users who are required to communicate in the presence of background noise while engaging in varying levels of physical effort. As a result, they may experience negative changes to objective and/or subjective voice characteristics during a regular season. The present data, concerning changes in female volleyball athletes' voice characteristics, need to be confirmed by studies with a larger number of participants.

Barbell Squat Relative Strength as an Identifier for Lower Extremity Injury in Collegiate Athletes.

Case, MJ, Knudson, DV, and Downey, DL. Barbell squat relative strength as an identifier for lower extremity injury in collegiate athletes. J Strength Cond Res 34(5): 1249-1253, 2020-The aim of the study was to determine the efficacy of using the relative strength level of Division I athletes in One repetition maximum (1RM) barbell back squat as an identifier of seasonal lower extremity (LE) injury. One repetition maximum back squat (kg) and reported LE injuries were retrospectively collected for Division I male football (n = 46), female volleyball and softball athletes (n = 25). Maximum preseason relative (body mass normalized) back squat strength values were compared with 2 analyses of variance (p < 0.05) between injured and uninjured male (football) and female athletes (softball & volleyball). Relative back squat strength was significantly lower in injured athletes than uninjured athletes in both men (F = 6.03, p = 0.02) and women (F = 4.68, p = 0.04) with a moderate to large effect size (g = 0.86-0.85). These data indicate the potential of 1RM back squat relative strength serving as one tool in multi-factor preseason screening for LE injury risk in these sports. Male athletes with relative squat strength below 2.2 and female athletes below 1.6 in these sports could be more susceptible to LE injury over a season. Strength professionals should consider using body mass normalized 1RM back squats as a screening tool for seasonal LE injury risk in college athletes.

Using Motion Sensor Technology to Manage Risk of Injury in a Strength and Conditioning Program for Female Collegiate Athletes

Background of Study: Females generally have a 6-8 times higher risk for lower extremity injury compared to male counterparts due to biomechanical differences and/or poor landing strategies. In recent years, a great deal of focus has been placed on prevention and reduction of non-contact lower extremity injuries. This has spurred the development of assessment methods to determine how athletes move and tools with which those motions are measured. Efforts have been made to measure and quantify movement strategies, which have given rise to multiple movement tests and measurement devices. One approach is the use of wearable technologies used in conjunction with a movement screening. Objective: Demonstrate a practical approach of using wearable technologies to guide training regimens in a population of female athletes that would be considered at risk for lower extremity injuries. Methods: A cohort of Division I female volleyball athletes were screened using wearable technology then assigned an intervention based on screening results. Comparisons were made between injury rates during the season when the intervention was applied compared to previous seasons. Results: All lower extremity injury rates were reduced after the intervention was applied. Conclusions: The use of wearable technology aids in quantifying movement to then assign a strategic intervention to reduce injuries in an at risk athletic population.

Pelvic Floor Muscle Training in Female Athletes: A Randomized Controlled Pilot Study.

The aim of this study was to investigate the effects of pelvic floor muscles training in elite female volleyball athletes and whether it is an effective therapy for stress urinary incontinence. Fourteen athletes, both continent and incontinent, between 18 and 30 years of age, were randomly assigned to an experimental group or a control group. The experimental group received a protocol for pelvic floor muscle training for 4 months. This consisted of three phases: awareness/stabilization, strength training and power. The control group was not subject to any intervention during the same period. Measures were collected at the initial and final phase for both groups. Maximum voluntary contractions were evaluated with a perineometer, involuntary urine loss with a Pad test and quality of life with the King's Health Questionnaire. Baseline sociodemographic and anthropometric characteristics were not significantly different. Comparing the two groups, the experimental group improved maximum voluntary pelvic contractions (p<0.001) and reduced urine loss (p=0.025), indicating the existence of significant differences between groups in the variation from the initial and final phases. The percentage of urine loss decreased in the experimental group, from 71.4-42.9%, suggesting that the protocol intervention for 16 weeks may help athletes with stress urinary incontinence.

Deep Vein Thrombosis in Lower Extremity of a Female Collegiate Volleyball Athlete: A Case Study

Deep vein thrombosis (DVT) occurs when a blood clot forms in deep veins in the body, usually in the lower extremity. DVT is commonly seen in older or hospitalized patients. This case is unique because the patient, is a 20-year-old female division III collegiate volleyball athlete, which is not the typical age or population affected by DVT or clotting disorders. The patient presented with swelling, pain, and decreased knee flexion (3/5) and plantarflexion (4/5) strength in her left lower extremity. These impairments reduced her ability to walk or run. The patient’s athletic trainer (AT) incorrectly diagnosed her with a left gastrocnemius muscle strain, resulting in contraindicated treatments. The AT referred the patient to the team physician, who referred her to the Emergency Department (ED) where she received a real-time grayscale and Doppler ultrasound of the left lower extremity deep venous structures, leading to the DVT diagnosis. The patient received a dose of Lovenox, an intravenous anticoagulant, by the ED physician. The following day, she began 15 mg of Xarelto, twice per day for 21 days, to dissolve the blood clots. She could not participate in volleyball for approximately two weeks, which reduced her ability to socialize with teammates and coaches. The Wells’ scoring system is a clinical prediction tool to identify patients with low risk of being diagnosed with DVT. The AT did not include this tool in their initial evaluation, leading to a delay in the diagnosis and treatment. Although the patient reported that she had a positive outcome, ATs should be familiar with the Wells Clinical Prediction Rule. Blood clots in veins can dislodge and travel through the bloodstream. The loose clot can block blood flow in the lungs, forming a pulmonary embolism. Early diagnosis can prevent this life-threatening condition.

Labral Tear in The Acetabulofemoral Joint in A Collegiate Female Athlete: A Case Study

This case investigates ongoing hip pain in a female collegiate beach volleyball athlete. The initial assessment, after thorough evaluation by the university’s athletic training staff, was iliotibial band tightness with concern of a tear of the patient’s acetabular labrum. The patient was religious to rehabilitation, performing it at least 3 times a week for 3 weeks, and was still having post-activity pain in her hip.

Sport Specialization and Coordination Differences in Multisport Adolescent Female Basketball, Soccer, and Volleyball Athletes.

Early sport specialization, or the participation in 1 sport year-round to the exclusion of all others, is a growing concern in youth athletics because of its possible association with musculoskeletal injury. The underlying injury risk may be the result of coordination differences that sport-specialized athletes have been speculated to exhibit relative to multisport athletes; however, little evidence exists to support or refute this notion. To examine relative hip- and knee-joint angular-motion variability among adolescent sport-specialized and multisport female adolescent athletes to determine how sport specialization may affect coordination. Cohort study. Research laboratory. A total of 366 sport-specialized and 366 multisport adolescent female basketball, soccer, and volleyball players. Drop-vertical-jump (DVJ) assessment. Average coupling-angle variability (CAV) for hip flexion and knee flexion, knee flexion and ankle flexion, hip flexion and knee abduction, knee flexion and knee abduction, knee flexion and knee internal rotation, and knee abduction and knee internal rotation. The sport-specialized group exhibited increased coupling variability in dominant-limb hip flexion and knee flexion (P = .015), knee flexion and knee abduction (P = .014), and knee flexion and knee internal rotation (P = .048) while landing during the DVJ, although they had small effect sizes (η2 = 0.010, 0.010, and 0.007, respectively). No differences were present between groups for any of the other CAV measures of the dominant limb, and no differences were found for any CAV measures of the nondominant limb (all P values > .05). Sport specialization was associated with increased variability of critical hip- and knee-joint couplings responsible for effective landing during the DVJ. Altered coordination strategies that involve the hip and knee joints may underlie unstable landings, inefficient force-absorption strategies, or greater contact forces that can place the lower extremities at risk for injury (or a combination of these).

Effect of sleep efficiency on salivary metabolite profile and cognitive function during exercise in volleyball athletes.

Sleep duration is known to affect physiological and circadian metabolites and human homeostasis. However, little is known about the relationship between sleep quality and metabolite and cognitive function during exercise. Therefore, the aim of the present study was to investigate the impact of sleep quality on metabolite level and cognitive function in female volleyball athletes. Twelve female volleyball athletes participated in this study. Sleep efficiency was measured for 1 week using NemuriSCAN (Paramount Bed Co. Ltd., Japan) as an index of sleep quality. The subjects were divided into better (n = 6) and lesser (n = 6) sleep quality groups by the median value of sleep efficiency. Saliva samples were collected using a Salimetric oral swab cotton and salivary metabolites were analysed using capillary electrophoresis and time-of-flight mass spectrometry. The subjects performed Stroop tasks (simple and difficult tasks) at rest and during aerobic exercise in recumbent cycle ergometer at light and heavy intensity. Increased sleep efficiency was found in the better sleep quality group, whereas total sleep time was similar. There were differences in urea cycle and Krebs cycle metabolites between the two groups; their levels were correlated with sleep efficiency. The difficult-task response time during heavy exercise was faster in the better sleep quality group. We demonstrated that sleep efficiency was associated with urea cycle and Krebs cycle metabolite levels and response time during heavy exercise in volleyball athletes. These results suggested that sleep quality may affect amino acid and energy metabolism and cognitive function during heavy exercise.

DEVELOPMENT OF AN UPPER EXTREMITY ‘SWING COUNT’ and Performance Measures in NCAA Division I Volleyball Players over A COMPETITIVE SEASON

Monitoring the volume of activity (i.e. pitch counts) and tracking upper extremity (UE) performance changes is common in overhead athletes; however, a lack of evidence exists for volleyball players.Purpose: The purpose of this study was to investigate changes in shoulder mobility, strength, and pain, along with UE swing count volume in Division I collegiate female volleyball athletes over a competitive season.Study Design: Observational, longitudinal study. Swing count data was collected during two separate days of practice during weeks 1, 7, and 14 of the competitive season. Perceived swing counts were collected after each practice from athletes and two coaches. Actual swing counts were tallied by retrospective viewing of video footage. Dominant shoulder internal (IR) and external rotation (ER) range of motion (ROM) and isometric strength, along with UE pain, were assessed on five occasions: baseline, in-season (weeks 1, 7, 14) and post-season (week 22). Five Division I female volleyball athletes participated. Perceived UE swing counts among coaching staff were significantly correlated with actual swing count (r = 0.93 - 0.98, p<.05), while athlete perceived swing count was moderately correlated and was not statistically significant (r = 0.64, p = .25). Shoulder IR ROM decreased from baseline to week 14 (-5.6 ± 10.6, 95% CI: -18.76, 7.6; p = .03), with a large effect size (d = 1.0). Large effect sizes were observed for increases in UE pain, shoulder ER ROM, and IR strength (d = 0.8 - 2.3). An increase in shoulder IR strength occurred from baseline to week 14 (p = .001), but decreased during the eight weeks of post-season relative rest (p = .02). UE swing count estimates by coaching staff demonstrated higher correlation with actual swing counts obtained through video recording, as compared to volleyball athlete self-report. This cohort experienced increased shoulder IR strength and ER ROM over a competitive season. Shoulder IR ROM decreased during the first 14 weeks with a large effect size. Monitoring UE performance changes and swing count volume may have implications for injury prevention and program development for volleyball athletes. Level 2B.

Lower Extremity Biomechanics Are Altered Across Maturation in Sport-Specialized Female Adolescent Athletes.

Sport specialization is a growing trend in youth athletes and may contribute to increased injury risk. The neuromuscular deficits that often manifest during maturation in young, female athletes may be exacerbated in athletes who specialize in a single sport. The purpose of this study was to investigate if sport specialization is associated with increased lower extremity biomechanical deficits pre- to post-puberty in adolescent female athletes. Seventy-nine sport-specialized female adolescent (Mean ± SD age = 13.4 ± 1.8 years) basketball, soccer, and volleyball athletes were identified and matched with seventy-nine multi-sport (soccer, basketball, and volleyball) female athletes from a database of 1,116 female adolescent basketball, soccer, and volleyball athletes who were enrolled in one of two large prospective, longitudinal studies. The athletes were assessed over two visits (Mean ± SD time = 724.5 ± 388.7 days) in which they were classified as pre-pubertal and post-pubertal, respectively. Separate 2 × 2 analyses of covariance were used to compare sport-specialized and multi-sport groups and dominant/non-dominant limbs with respect to pubertal changes in peak knee sagittal, frontal, and transverse plane joint angular measures and moments of force recorded while performing a drop vertical jump task. The sport-specialized group were found to exhibit significantly larger post-pubertal increases in peak knee abduction angle (p = 0.005) and knee abduction moment (p = 0.006), as well as a smaller increase in peak knee extensor moment (p = 0.032) during landing when compared to the multi-sport group. These biomechanical changes are indicative of potentially compromised neuromuscular control that may increase injury risk pre- to post-puberty in sport-specialized female athletes. Consideration of maturation status may be an important factor in assessing the injury risk profiles of adolescent athletes who specialize in sport.

Effects Of A Pre-season Intervention On Hydration In Female Collegiate Volleyball Athletes

Urine specific gravity (USG) is commonly utilized to assess hydration status. Athletic performance has been shown to be affected by hydration status. In addition to nutritional and hydration practices, environmental conditions can also influence hydration status. Therefore, healthcare professionals should also consider environment, both indoor and outdoor, when assessing hydration. PURPOSE: To compare base-line USG to season-long urine collections following a one-time, pre-season hydration intervention. METHODS: Fourteen NCAA Division II female collegiate volleyball athletes participated in this study. Urine was collected in sterile cups in the hours preceding either a game or practice. Collections were roughly two weeks apart, starting August 25th and ending November 4th, 2017, resulting in eight total collections. The hydration intervention consisted of information and guidelines presented to the team and coaching staff. The intervention was administered verbally immediately following base-line urine collection. Written guidelines were left with athletes and coaching staff. Urinalysis was conducted via reagent strips. Data was analyzed via SPSS v.22 with an a priori level of 0.05. Subsequent urinalyses were compared to the baseline urinalysis. RESULTS: USG statistically decreased from base-line to the second collection and did not statistically differ again until the final three collections (base-line = 1.021±0.008, 1.007±0.003*, 1.015±0.008, 1.013±0.006, 1.020±0.016, 1.014±0.005*, 1.011±0.008*, and 1.013±0.003*, *p < 0.05 compared to baseline). DISCUSSION: The hydration intervention illustrated a short-term effect on USG. A correlation between USG and environmental temperatures was evaluated post hoc for the final six urine collections, arguably when the effects of the intervention had subsided. The coefficient of determination (r2) revealed that 35.7% of the difference in USG was due to the environmental temperature, which was statistically significant (r = 0.597, p<0.05). CONCLUSION: The intervention appeared to have a limited impact on USG. Differences in USG were evident again later in the season (late October to early November). Further analysis demonstrated a statistical influence of cooler temperatures on lower USG near the end of season.

Kinetic Analysis of Unilateral Landings in Female Volleyball Players After a Dynamic and Combined Dynamic-Static Warm-up.

Avedesian, JM, Judge, LW, Wang, H, and Dickin, DC. Kinetic analysis of unilateral landings in female volleyball players after a dynamic and combined dynamic-static warm-up. J Strength Cond Res 33(6): 1524-1533, 2019-A warm-up is an important period before training or competition to prepare an athlete for the physical demands of subsequent activity. Previous research has extensively focused on the effects of warm-up in relation to various jumping performance attributes; however, limited research has examined the biomechanical nature of landings after common warm-up practices. Twelve female, collegiate-level volleyball players performed unilateral landings on the dominant and nondominant limb before and after dynamic warm-ups and combined dynamic-static (CDS) warm-ups. Kinetic variables of interest were measured at the hip and knee during the landing phase of a volleyball-simulated jump-landing maneuver. A significant 3-way interaction (warm-up × limb × time) for peak internal knee adduction moment was observed, as this kinetic parameter significantly increased (p = 0.01; d = 0.79) in the nondominant limb at 1-minute post-CDS warm-up. No other warm-up differences were detected; however, significant main effects of limb were determined for dominant-limb internal hip abduction moment (p < 0.01; d = 1.32), dominant-knee internal rotation moment (p < 0.01; d = 1.88), and nondominant-knee external rotation moment (p < 0.01; d = 1.86), which may be due to altered hip and trunk mechanics during the jump landings. This information provides strength and conditioning professionals with biomechanical information to determine warm-up protocols that reduce the risk of injury in female volleyball athletes.