Sports Health-A Multidisciplinary Approach最新文献

Background: The cumulative effect of repetitive subconcussive head impacts on neurocognitive function during youth contact sports remains largely unknown. There is a paucity of literature evaluating cumulative helmet forces over a season and their correlation with preseason and postseason cognitive performance tasks such as the King-Devick test (KDT).

Hypothesis: Higher helmet forces recorded throughout a 10-week, 10-game youth football season would correlate with slower performance on postseason KDT.

Study design: Prospective cohort study.

Level of evidence: Level 3.

Methods: A cohort of 58 youth football players (ages 9-13 years) underwent pre- and postseason KDT. Players wore SpeedFlex helmets (Riddell) fitted with InSite Impact Response System helmet accelerometers (Riddell) which recorded impacts of ≥15g. Head impacts were tallied over a season and assigned a score of 1, 2, or 3 based on magnitude of g forces. Suspected concussions were correlated with KDT times and recorded instances of head impact. Pre- and postseason KDT scores were compared.

Results: During the season, 2013 head impacts were recorded. Median (range) total cumulative force score was 24 (5-476); 6 players sustained head impacts concerning for concussion, and 4 were clinically diagnosed with concussions. Overall, postseason KDT times improved compared with preseason, with a median (range) change of -4.8 seconds (-7.6, -1.1). Analysis showed no correlation between changes in KDT time and total cumulative force score over the season.

Conclusion: KDT times in youth football players did not change significantly based on head impact exposure over a single youth football season; most players' KDT times improved from preseason to postseason.

Clinical relevance: Although our study did not show significant cognitive impact as measured by KDT over a single youth football season, the long-term effects of concussion on the immature brain and how it can impact cognitive development remains largely unknown and should be an area of ongoing study.

Background: Previous studies have identified demographic, radiographic, and intraoperative predictors of outcomes after hip arthroscopy for femoroacetabular impingement syndrome, yet few studies have identified whether preoperative gait metrics can predict outcomes.

Hypothesis: Increased preoperative step count, walking speed, step length, and gait symmetry will be associated with better outcomes after surgery.

Study design: Retrospective cohort study.

Level of evidence: Level 4.

Methods: Patients who underwent hip arthroscopy between 2019 and 2022 and downloaded the smartphone app rHip, allowing for retroactive access of gait metric data, were identified. Preoperative gait metrics, age, sex, body mass index (BMI), and exercise participation were analyzed via multivariate stepwise linear regression for a relationship with 1-year postoperative patient-reported outcomes (PROs), including Hip Outcome Scale-Activities of Daily Living (HOS-ADL); HOS-Sports Subscale (HOS-SS), and 12-item international Hip Outcome Tool (iHOT-12). Thresholds for preoperative gait metrics were analyzed via receiver operator characteristic curve. A subgroup analysis was performed to compare those who did and did not reach this threshold.

Results: A total of 43 patients (86% female; age, 33.1 ± 13.7 years; BMI, 23.9 ± 4.4 kg/m²) met inclusion criteria. Multivariate regression found that preoperative walking speed was significantly associated with postoperative HOS-ADL, HOS-SS, and iHOT-12 (P ≤ .01). A preoperative walking speed threshold of 1.065 m/s was predictive of outcome achievement. Those who failed to achieve this threshold were significantly older, of greater BMI, and less active (P ≤ .04). They also showed significantly worse 1-year postoperative scores (P ≤ .02) and lower PASS achievement for HOS-ADL, HOS-SS, and iHOT-12 (P ≤ .04).

Conclusion: Preoperative walking speed is significantly associated with 1-year outcomes after hip arthroscopy. Patients who averaged <1.065 m/s show significantly worse outcomes after surgery.

Clinical relevance: Assessment of preoperative walking speed may allow physicians to better counsel patients regarding expected outcomes after hip arthroscopy.

Background: Exercise and its effect on cardiovascular diseases have been extensively studied in the elderly population. The difference in blood pressure (BP) between fit and unfit subjects can be >5 mmHg. It is not well established whether the positive effects of exercising on BP are associated with exercise type, be it aerobic or anaerobic (maximal muscle strength).

Hypothesis: Anaerobic training (maximal muscle strength) causes greater improvements than aerobic training on BP in active older adults.

Study design: Clinical trial.

Level of evidence: Level 4.

Methods: This clinical trial was carried out with 202 participants (n = 116 aerobic program [ABPG], n = 86 strength program [SBPG]; 58.05% female; age 67.61 ± 5.01 years). The training program was carried out between 2018 and 2021. Periodic evaluations of BP (systolic BP [SBP] and diastolic BP [DBP]) were conducted with a frequency of twice per year. BP comparisons were made by using 2 × 2 analysis of variance with repeated measurements over the course of the 4 years of the project.

Results: Throughout the training program, SBPG showed significant and consistent improvements in both SBP and DBP (P < 0.01). On the other hand, the ABPG reported a significant initial improvement (P < 0.01), which was not repeated in subsequent years. BP monitoring carried out over the 4 years showed a decrease in DBP and SBP, with this decrease being more pronounced in SBPG. However, the differences between the groups were not significant (2021; DBP, F = 1.227; P = 0.27; SBP, F = 0.826, P = 0.36).

Conclusion: Among persons aged ≥65 years, muscle strength training programs appear to be more effective in inducing exercise-related positive changes in BP and cardiovascular risk factors compared with aerobic exercise programs.

Clinical relevance: Muscle strength training programs result in favorable changes in BP and cardiovascular risk factors.

Background: Overuse injuries in youth athletes are associated with risks, including sports specialization, biological maturation, female sex, and workload measures. As no assessment tool exists to evaluate risk accumulation, we developed a novel risk factor scoring system (Sport Training Assessment of Risk [STAR]) to assess participants' risk of overuse injury and explore association with return-to-play (RTP) time periods.

Hypothesis: (1) STAR will reach an acceptable predictive threshold in the assessment of overuse injury in youth athletes. (2) Higher STAR scores will be associated with increased RTP time periods after injury.

Study design: Longitudinal cohort study.

Level of evidence: Level 3.

Methods: Youth athletes with an injury sustained during competitive sport completed questionnaires. Association of questionnaire variables with injury risk type was evaluated via logistic regression analyses, and unweighted and weighted versions of a total risk score were developed. RTP was defined by physician clearance per electronic medical record review. Mantel-Haenszel chi-square tests and Kendall's rank correlation coefficients were used to assess the relationship between weighted total risk score and RTP time periods. The weighted STAR model was analyzed with receiver operating characteristic (ROC) curves.

Results: The weighted STAR model trended toward an acceptable level of prediction for overuse (nonserious + serious) injury (area under the ROC curve [AUC], 0.66; 95% CI, 0.61-0.71), but was less predictive for serious overuse injury (AUC, 0.63; 95% CI, 0.55-0.71). Weighted total risk score was weakly associated with return to full play (ρ = 0.11; P < 0.01), and potentially with return to modified play (ρ = -0.08; P = 0.04).

Conclusion: STAR may be a feasible tool for assessing overuse injury risk and RTP time periods in youth athletes but requires further development, as it did not reach an acceptable predictive threshold in this preliminary study.

Clinical relevance: Clinicians can use STAR to assess overuse injury risk in youth athletes.

Background: Many questions persist regarding the relationship between training load and injuries in volleyball, as well as the best method for calculating acute:chronic workload ratio (ACWR). This study aimed to investigate the relationship between different metrics of training load and risk of injury in male professional volleyball players.

Hypothesis: ACWR, as a training load measure, is useful for identifying injury risk in volleyball players, regardless of calculation method.

Study design: Longitudinal, prospective, and observational design conducted over 3 seasons of professional male volleyball.

Level of evidence: Level 3.

Methods: The study included 43 male volleyball players. Internal training load was quantified using the Session Rating of Perceived Exertion. From daily training load values, absolute measures and relative measures were computed. For relative measures, 7 days were employed for acute training load, and 21 and 28 days for chronic training load. A distinction was made between coupled calculation and uncoupled calculation. Injuries were documented using the Injury Surveillance Form proposed by the International Volleyball Federation.

Results: ACWR calculated in a coupled manner and by a rolling average demonstrated higher injury risks when analyzing the complete periods (odds ratio [OR] ACWR 7:28 = 2.040; ACWR 7:21 = 1.980) and competitive period (OR ACWR 7:28 = 2.044; ACWR 7:21 = 2.087). In contrast, during the preseason, the coupled exponential averages were more sensitive to the risk of injury (OR ACWR 7:28 = 4.370; ACWR 7.504).

Conclusion: Both measures using rolling averages and those calculated from exponential averages can be employed to identify the risk of injuries in volleyball athletes.

Clinical relevance: The findings of this study can be useful to coaching staff, fitness trainers, and healthcare professionals involved in the challenge of reducing the risk of injury in volleyball athletes. The need for continuous monitoring and real-time adjustments of training load is emphasized.

Background: Australian Rules Football athletes complete long preseasons, yet injuries occur frequently at early stages of the competitive season. Little is known about the high-speed running (HSR) prescription during a preseason or whether players are adequately prepared for competition. This study described absolute and relative preseason and in-season HSR demands of 2 professional Australian football teams.

Hypothesis: HSR and sprinting volumes are significantly lower in elite Australian Rules football athletes during in-season compared with preseason.

Study design: Cohort study.

Level of evidence: Level 3.

Methods: During the 2019 season, HSR volume was collected for 2 professional Australian football teams (n = 55). Individual maximum speeds (V_max) were captured to calculate relative running speed thresholds, as reported in 5% increments from 70%V_max to 100%V_max.

Results: Weekly volume of running above 70%V_max (P = 0.01; r = 0.56) and 80%V_max (P = 0.01; r = 0.58) was significantly greater in the preseason than the in-season. The weekly volume completed above 90%V_max was not significantly greater in the preseason than the in-season (P = 0.10; r = 0.22). Individual variation in the distance completed at specific percentages of V_max expressed as a coefficient of variation was reported as 51% at 71% to 80%V_max, 39% at 81% to 90%V_max, and 41% at 91% to 100%V_max.

Conclusion: The volume of HSR completed by athletes is far greater in the initial 4 weeks of the preseason than in any other point in preseason or competitive phases. At the individual level, there is substantial variation in the distance covered. This supports the concept of a heavily individualized approach to high-speed prescription and monitoring.

Clinical relevance: Practitioners should carefully consider individual variation regarding sprinting volume during both preseason and in-season when prescribing and monitoring training to improve on-field performance and reduce the risk of injury.

Background: Monitoring training load has the potential to improve sport performance and reduce injuries in athletes. This study examined training load and its association with wellness in artistic gymnastics.

Hypotheses: Training load and changes in training load (acute:chronic workload ratio [ACWR]) vary throughout 1 season; wellness is inversely correlated with training load and ACWR.

Study design: Prospective case series.

Level of evidence: Level 3.

Methods: A total of 30 female collegiate gymnasts from 4 Division I National Collegiate Athletic Association teams participated (mean age, 20 ± 2 years). During 4 months, before daily training, wellness surveys assessed sleep, energy, soreness, and mood (1-10; higher = better). After daily training, training load surveys assessed training duration per event (warm-up, vault, bars, beam, floor, strength and conditioning) and session rating of perceived exertion (RPE; 1-10; 10 = hardest) per event. Coaches reported technical complexity of training per event (1-4; 4 = hardest). Training load was calculated as [duration] × [RPE] × [technical complexity]. ACWR represented a ratio between acute [1-week] and chronic [4-week rolling average] training loads.

Results: ACWR and weekly training load fluctuated throughout the season (ACWR mean weekly range: 0.68-1.11; training load mean weekly range: 2073-6193 arbitrary units). ACWR and weekly training loads were trichotomized into low, medium, and high groups; positive correlations were observed between each wellness variable and ACWR (P < 0.01) and between each wellness variable and weekly training load (P < 0.01).

Conclusion: Our novel training load monitoring framework for women's college gymnastics enabled us to characterize training load and its relationship with wellness throughout 1 season. This method should be explored in gymnasts across various ages and competitive levels.

Clinical relevance: This study proposes a framework and the initial findings of monitoring training load and wellness in collegiate women's gymnastics.

Background: Monitoring training load and competition load is crucial for evaluating and improving athlete performance. This study proposes an applied approach to characterize and classify the training task specificity in relation to competition in a top-level rink hockey team, considering external and internal load from training tasks and competition.

Hypothesis: Training tasks and game demands have significant dose-response differences, and exercises can be classified successfully based on their physiological and biomechanical demands.

Study design: Cross-sectional study.

Level of evidence: Level 5.

Methods: Ten elite-level male rink hockey players participated in this study. Players were monitored on 6 different task categories during 8 training sessions and 2 official games. A linear mixed model with random intercepts was used to compare training tasks and competition load, accounting for individual repeated measures. A 2-step cluster analysis was performed to classify the training tasks and games based on physiological and biomechanical load, employing log-likelihood as the distance measure and Schwartz's Bayesian criterion.

Results: Average heartrate, maximum heartrate, and high-speed skating (18.1-30 km/h) were the best physiological load predictors, while the most effective biomechanical load predictors were impacts [8-10] g(n), decelerations [-10 to -3]m/s²(n), and accelerations [3-10]m/s²(n). Different physiological and biomechanical responses were verified between training tasks and match demands. A 4-quadrant efforts assessment for each task category revealed that training tasks used by the team in the analysis presented lower biomechanical and physiological load demands than competition.

Conclusion: Training tasks failed to adequately replicate the specific demands of competition, especially regarding high mechanical stress, such as the absence of high-intensity impacts and decelerations.

Clinical relevance: This method of classification of training tasks may allow coaches to understand further the specificity and contribution of each task to competition demands, consequently improving the capacity of load management and the preparedness and readiness of players for competition.

Background: This study aimed to compare acceleration and deceleration demands of intercounty Camogie players, and differences across playing positions and halves of play.

Hypothesis: The middle 3 positions will have greatest accelerations and decelerations variables across match play and halves of play.

Study design: Nonrandomized, repeated measures design.

Level of evidence: Level 4.

Methods: Global positioning systems (GPS) (10 Hz) collected data from 28 participants during 18 competitive matches across 2 seasons; 206 individual player datasets were analyzed.

Results: Half-backs (P < 0.05; effect size [ES], -1.75) and midfielders (P < 0.05; ES, -1.68) covered significantly greater total number of accelerations than full-forwards. In acceleration zone 4, midfielders (P < 0.05; ES, = -1.67) and half forwards covered a significantly greater number than full-forwards (P < 0.01; ES, = -1.41). Midfielders accumulated a significantly greater distance in acceleration zone 4 than full-backs (P < 0.05; ES, = -0.57). Significant decrements were observed between halves in total number of accelerations (P < 0.01; ES, = 0.49), accelerations in zones 1 to 4 (P < 0.01; ES, 0.16-0.43), total distance of accelerations, and acceleration distance in zones 2 to 4 (P < 0.05; ES, 0.25; P < 0.01; ES, 0.45; P < 0.01; ES, 0.38). There were significant decrements in the total number of decelerations (P < 0.01; ES, 0.43), number of decelerations in zones 2 (P < 0.05; ES, 0.25), 3 (P < 0.01; ES, 0.45), and 4 (P < 0.01; ES, 0.38), and total deceleration distance (P < 0.01; ES, 0.16).

Conclusion: Half-backs and midfielders covered significantly greater total number of accelerations than full-forwards. Significant decrements in several acceleration and deceleration variables were observed between halves.

Clinical relevance: Players competing in intercounty Camogie should receive progressive exposure to acceleration and deceleration-based movement demands to prepare players for intercounty Camogie match play.

Background: The aim of this study was to determine the influence of different percentages of blood flow restriction (BFR) and loads on mean propulsive velocity (MPV) and subjective perceived exertion during squat (SQ) and bench press (BP) exercises.

Hypothesis: Higher percentages of BFR will positively affect dependent variables, increasing MPV and reducing perceived exertion.

Study design: Cross-sectional study.

Level of evidence: Level 3.

Methods: Eight healthy young male athletes took part. Two sets of 6 repetitions at 70% 1-repetition maximum (1RM), 2 sets of 4 repetitions at 80% 1RM, and 2 sets of 2 repetitions at 90% 1RM were performed randomly; 5-minute recoveries were applied in all sets. The varying arterial occlusion pressure (AOP) applied randomly was 0% (Control [CON]), 80%, and 100%.

Results: No statistically significant differences in MPV were found during the BP exercise at any percentage of BFR at any percentage 1RM. During the SQ exercise, MPV results showed statistically significant increases of 5.46% (P = 0.04; η_p² = 0.31) between CON and 100% AOP at 90% 1RM. The perceived exertion results for the BP exercise showed statistically significant reductions of -8.66% (P < 0.01; η_p² = 0.06) between CON and 100% AOP at 90% 1RM. During the SQ exercise, the perceived exertion results showed significant reductions of -10.04% (P = 0.04; η_p² = 0.40) between CON and 100% AOP at 80% 1RM; -5.47% (P = 0.02; η_p² = 0.48) between CON and 80% AOP at 90% 1RM; and -11.83% (P < 0.01; η_p² = 0.66) between CON and 100% AOP at 90% 1RM.

Conclusion: BFR percentages ~100% AOP at 90% 1RM improved acutely MPV (only in SQ exercises) and reduced acutely perceived exertion (in both exercises). These findings are important to consider when prescribing resistance training for healthy male athletes.