Is Increased Kicking Leg Iliopsoas Muscle Tightness a Predictive Factor for Developing Spondylolysis in Adolescent Male Soccer Players?

OBJECTIVE: To identify predictive risk factors of lumbar stress (LS) fracture developing from an asymptomatic stress reaction of the pedicle among adolescent male soccer players. DESIGN: Prospective cohort study. SETTING: Amateur Japanese adolescent male soccer team. PARTICIPANTS: Japanese adolescent male soccer players (n = 195) aged 12 to 13 years. ASSESSMENT OF RISK FACTORS INDEPENDENT VARIABLES: Height, body weight, body mass index, muscle tightness of both lower extremities (iliopsoas, hamstrings, and quadriceps), lumbar bone mineral content, developmental age, and lumbar lordosis angle were measured as baseline measurements. MAIN OUTCOME MEASURES DEPENDENT VARIABLE: Players who were diagnosed with an asymptomatic stress reaction of the lumbar spine pedicle at baseline were followed; extension-based lumbar pain was defined 1 year after the baseline. The players were assigned to the LS fracture or control (CON) group at follow-up. RESULTS: At baseline, 40 boys were diagnosed with an asymptomatic stress reaction of the lumbar spine pedicle. The difference in muscle tightness between the kicking leg and supporting leg was significantly different (P = 0.012) between the LS (n = 16) and CON (n = 22) groups. Increase in iliopsoas muscle tightness in the kicking leg was a predictive risk factor of developing extension-based lumbar pain after adjusting for developmental age and body mass index (odds ratio, 1.54; 95% confidence interval, 1.05-2.27). CONCLUSIONS: Development of extension-based lumbar pain from an asymptomatic stress reaction of the pedicle among adolescent male soccer players was associated with increased iliopsoas muscle tightness of the kicking leg relative to that of the supporting leg.

History, Knowledge, and Education of Sport-Related Concussion Among College Athletes in Japan.

CONTEXT: Few authors have investigated sport-related concussion (SRC) awareness and knowledge among athletes in Japan. Sport-related concussion research is scarce among Asian compared with North American and European cohorts. OBJECTIVE: To examine previous SRC history, level of SRC knowledge, and previous exposure to SRC education among collegiate athletes in Japan by the level of contact and access to medical staff. DESIGN: Cross-sectional study. SETTING: Single-university study in Japan. PATIENTS OR OTHER PARTICIPANTS: A total of 2103 athletes (48 varsity teams) were contacted to participate in an anonymous survey. Data from athletes with (1) SRC history in the past 3 months, (2) persistent SRC symptoms, (3) nontraditional sports, or (4) incomplete surveys were excluded. As a result, data from 593 athletes representing 43 varsity teams were included in this analysis. MAIN OUTCOME MEASURE(S): Outcome measures were level of contact (contact [CON], limited contact [LTD], noncontact [NC]), access to medical staff (MEDYES, MEDNO), SRC knowledge (maximum score of 49), previous SRC history (self-report; yes, no), and previous SRC education (self-report; yes, no). RESULTS: The average SRC knowledge total score was 33.4 ± 6.1 (range, 18-48). The knowledge score in CON was higher than in LTD and NC (P < .001) and in MEDYES than MEDNO (median, MEDYES = 34.0, MEDNO = 32.0; U = 27 841.5, P < .001). Sport-related concussion history was statistically different by the level of contact ( = 27.95, P < .001) and by access to medical staff ( = 4.5, P = .034). The presence of an SRC history and previous SRC education contributed to higher SRC knowledge, independent of the level of contact and access to medical staff (P < .001). CONCLUSIONS: Japanese athletes who participated in CON sports had a higher prevalence of SRC history, higher knowledge, and greater exposure to SRC education than those in LTD or NC sports. Access to medical staff was associated with higher SRC knowledge.

Question Format Matters: Do Athletes Really Know the Signs and Symptoms of a Sport-Related Concussion?

Authors of previous studies commonly used a multiselect checklist method to assess an athlete's ability to recognize true sport-related concussion (SRC) signs and symptoms (S&S) among incorrect distractor options. However, this may overinflate the evaluation of participants' knowledge because the multiselect method does not test athletes' ability to retrieve knowledge from their long-term memory. To examine this hypothesis, we sent an online survey to registered members of the Japan Lacrosse Association (n = 8530) to assess differences in reported SRC S&S by open-ended-question and multiselect formats. We also evaluated whether previous exposure to SRC education and a history of SRC influenced athletes' SRC S&S knowledge. The numbers and proportions of responses were calculated using descriptive statistics. The Pearson correlation was calculated to analyze the relationship between scores from the 2 question formats. Unpaired-samples t tests were conducted to compare the mean scores for each question format by previous SRC education and history of diagnosed SRC. Odds ratios were computed to express the relationship between the proportion of correct answers by question format per symptom. The response rate of the survey was 35.9% (n = 3065), and scores from the 2 question formats were correlated (r = 0.34, 95% CI = 0.31, 0.37; P < .001). For both question formats, athletes with previous exposure to SRC education and a history of SRC had a greater number of correct answers; however, the mean differences were trivial. Researchers and clinicians should acknowledge the difference between multiselect (recognition) and open-ended (free recall) formats when assessing one's understanding of SRC and managing athletes with a suspected SRC.

Case Report: Countermeasures Against Heat and Coronavirus for Japanese Athletes at the Tokyo 2020 Olympics and Paralympic Games.

The Tokyo 2020 Olympics and Paralympic Games were held in the hottest environment in the history of the games. Additionally, the worldwide coronavirus disease 2019 (COVID-19) pandemic necessitated daily polymerase chain reaction (PCR) testing during the games, wearing a mask became mandatory publicly, and it was an unheard and unique Olympic with no spectators. Heat acclimation, hydration, and body cooling are essential for safe and high-performance activities in hot environments. In 2015, the Japan Institute of Sports Sciences launched the "Heat Countermeasure Project" to conduct experiments and practical research on heat countermeasures and investigate issues related to heat countermeasures in each athletic event. The results obtained were proposed to various Japan national sports teams, and support for heat countermeasures for the Tokyo 2020 games was promoted in consultation with national federations. Furthermore, due to the COVID-19 pandemic, infectious disease countermeasures for the Tokyo 2020 Games during support were a must. Moreover, athletes, coaches, and team staff could not avoid implementing heat countermeasures while adopting measures against infectious diseases. This study aimed to clarify the issues faced with heat countermeasures and report on heat acclimation training and cooling support efforts, considering measures against infectious diseases.