Link Between Ferritin, Vitamin D, Performance, and Eating Attitudes in Female Athletes.

Iron and vitamin D deficiencies can affect athletes' health and performance. However, the epidemiology and associated risk factors remain unclear. Forty-three elite female athletics athletes (20.2 ± 1.9 years) were included. A survey regarding the training schedule and Eating Attitudes Test-26, body composition, bone mineral density, and serum 25-hydroxyvitamin D (25(OH)D) and ferritin levels were assessed. Mean serum 25(OH)D and ferritin levels were 25.2 ± 5.5 ng/mL and 29.0 ± 13.2 ng/mL, respectively, and 83.7% and 41.9 % of athletes had vitamin D and ferritin insufficiency, respectively. Serum 25(OH)D level was negatively correlated with the number of rest days per week (Coefficient, -6.19; 95% confidence interval [CI], -9.82--2.57; p = 0.002), and serum ferritin level was negatively correlated with body mass index (Coefficient, -3.87; 95% CI, -7.57--0.16; p = 0.041). Performance levels were positively correlated with serum vitamin D levels (Coefficients, 7.25; 95% CI, 0.25-14.25; p = 0.043) and negatively correlated with EAT-26 scores (Coefficient, -7.30; 95% CI, -12.61--1.98; p = 0.009) and body fat percentage (Coefficient, -13.26; 95% CI, -24.66--1.86; p = 0.025). Vitamin D and ferritin insufficiencies are prevalent among Japanese female athletics athletes. Serum vitamin D level was related to performance level.

Injuries and illness of athletes at the Tokyo 2020 Olympic and Paralympic summer games visiting outside facilities.

This study aimed to identify the reasons for transferring athletes to local medical facilities during the Olympic and Paralympic Games. Data on 567 injuries and other illnesses of athletes treated at the on-site clinics were collected from the Tokyo 2020 Organizing Committee. Of these, 84 athletes who required outpatient care during the Games were registered for this survey. During the Olympic and Paralympic Games, 66 (8.3/1 000) and 18 (7.2/1 000) athletes, respectively, consulted external medical facilities. In the Olympic Games, the reasons for these visits included 48 cases (72.7%) of injuries, 13 (19.7%) cases of illnesses, and 5 (7.6%) cases of heat stroke illness (HSI). Of these patients, 56 (84.9%) were treated as outpatients and 10 (15.1%) were hospitalized, while three of these patients required hospitalization for > 7 days. On the other hand, in the Paralympics Games, there were 7 (38.8%) cases of injuries, 9 (50.0%) other illnesses, 1 (5.6%) case of HSI, and 1 (5.6%) other cases, of which 11 (61.1%) were treated as outpatients and 7 (38.9%) were hospitalized, but none was hospitalized for > 7 days. Injuries accounted for 70% of the total cases at the 2021 Olympic Games, but only three (0.05%) were severe cases that required hospitalization for more than 1 week. In contrast, in the Paralympic Games, other illnesses accounted for approximately half of the total cases. This study provides details on the extent of injuries and other illnesses that were transferred to outside facilities, which has not been documented in previous games.

Navigating implementation barriers: a holistic approach to improving exertional heat stroke management.

Objectives: To assess the shift in medical volunteers' perception and practice surrounding exertional heat stroke (EHS) prehospital management after the Tokyo 2020 Olympic Games. Methods: An online survey was sent to medical volunteers assigned to work at high EHS risk events during the Tokyo 2020 Olympic Games. Surveys were sent at the time of initial training, immediately after the Games, and one year after the Games. The survey investigated medical volunteers' perceptions and practices regarding the assessment of rectal temperature and the use of whole-body cold water immersion (CWI) as prehospital management of EHS. In addition, an open-ended question was prepared to examine barriers and facilitators of their chosen perception and/or behaviour. Results: The lack of knowledge about rectal temperature assessment improved over time, but the actual implementation did not. Meanwhile, increased utilisation of CWI was observed 1 year after the Games. The lack of equipment, apprehension towards rectal temperature assessment, the perception of difficulty getting patient consent, concerns for hypothermic overshoot and the number of required medical providers were raised as barriers to implementation. Conclusion: Some improvements were observed in perception and practice; however, further organisational and financial support is warranted for a broader skill transfer and implementation.

International study of physicians' opinion on physician-patient sex concordance when treating athletes.

BACKGROUND: The effect of physician-patient sex concordance in medicine has been reported in many studies. Whether physicians believe that the sex concordance between physician and athlete influences treatment has not been investigated. OBJECTIVE: To determine whether physicians believe that the sex concordance between physician and athlete influences treatment. DESIGN: Cross-sectional study. SETTING: Online survey. PARTICIPANTS: One thousand one hundred ninety-three sports medicine physicians in 51 countries. Participants were sports medicine physicians trained in orthopedics (n = 443 [37.1%]) and nonorthopedics (n = 750 [62.9%]). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants were asked to decide whether sex of the physician made them better suited to care for athletes of concordant or different sexes along with their personal background. RESULTS: Orthopedic sports medicine physicians agreed less than nonorthopedic sports medicine physicians regarding the statement "MALE sports medicine physicians are better suited than their female counterparts to care for MALE athletes" (odds ratio [OR] 0.56, 95% confidence interval [CI] 0.35-0.91, p = .02), and compared to sports medicine physicians based in Europe, those based in Asia agreed more to this statement (OR 7.91, 95% CI 4.60-13.60, p < .01). In addition, regarding the statement "FEMALE sports medicine physicians are better suited than their male counterparts to care for FEMALE athletes," compared to sports medicine physicians based in Europe, those based in Asia (OR 9.12, 95% CI 5.63-14.79, p < .01) and North America (OR 2.18, 95% CI 1.46-3.25, p < .01) agreed more and orthopedic sports medicine physicians agreed less than nonorthopedic sports medicine physicians (OR 0.61, 95% CI 0.39-0.93, p = .02) to this statement. CONCLUSIONS: Sports medicine physicians trained in orthopedics felt sex concordance was less important than physicians trained in other specialties. Asian sports medicine physicians believed sex concordance was more important compared to physicians in other regions.

Emergency department activities at the Athletes' Village during the Tokyo 2020 Olympic and Paralympic Games.

Aim: More than 15,000 elite athletes participated in the Tokyo 2020 Olympic and Paralympic Games. Providing adequate medical services to these elite athletes was a priority. Hence, a polyclinic was established in the Athletes' Village. Visitors were triaged at the emergency department of the polyclinic to enable early treatment of critical illnesses or injuries in the emergency room (ER) and to identify patients suspected of having coronavirus disease as early as possible. No reports of emergency department activities at large sporting events in the pandemic era are available. Here, we aim to summarize the activities at the emergency department of the polyclinic. Methods: Data were collected using an electronic medical record system, nursing records, and questionnaires administered during triage from July 13 to September 8, 2021. Polyclinic data involving accredited athletes and team members were summarized. Results: During the Olympic Games, 12,318 triage cases were reported, of which 75 were treated in the ER. During the Paralympic Games, 8398 triage cases were reported, of which 94 were treated in the ER. During the Olympic Games, musculoskeletal issues (26 patients) were the most common. During the Paralympic Games, ear, nose, and throat issues were the most common (21 patients). Two patients experienced cardiopulmonary arrest in the Athletes' Village and were transported to the hospital postresuscitation. Conclusion: During the study period, many critically ill patients were triaged and treated at the emergency department. Our data can be used to improve medical care and infection prevention at future international sporting events.

Acute in-competition medical care at the Tokyo 2020 Olympics: a retrospective analysis.

OBJECTIVE: To analyse injuries and illnesses during the 2020 Tokyo Olympic Summer Games. METHODS: This retrospective descriptive study included 11 420 athletes from 206 National Olympic Committees and 312 883 non-athletes. Incidences of injuries and illnesses during the competition period from 21 July to 8 August 2021 were analysed. RESULTS: A total of 567 athletes (416 injuries, 51 non-heat-related illnesses and 100 heat-related illnesses) and 541 non-athletes (255 injuries, 161 non-heat-related illnesses and 125 heat-related illnesses) were treated at the competition venue clinic. Patient presentation and hospital transportation rates per 1000 athletes were 50 and 5.8, respectively. Marathons and race walking had the highest incidence of injury and illness overall (17.9%; n=66). The highest incidence of injury (per participant) was noted in boxing (13.8%; n=40), sport climbing (12.5%; n=5) and skateboarding (11.3%; n=9), excluding golf, with the highest incidence of minor injuries. Fewer infectious illnesses than previous Summer Olympics were reported among the participants. Of the 100 heat-related illnesses in athletes, 50 occurred in the marathon and race walking events. Only six individuals were transported to a hospital due to heat-related illness, and none required hospital admission. CONCLUSION: Injuries and heat-related illnesses were lower than expected at the 2020 Tokyo Olympic Summer Games. No catastrophic events occurred. Appropriate preparation including illness prevention protocols, and treatment and transport decisions at each venue by participating medical personnel may have contributed to these positive results.

Incidence and factor analysis for the heat-related illness on the Tokyo 2020 Olympic and Paralympic Games.

Introduction: Among the 43 venues of Tokyo 2020 Olympic Games (OG) and 33 venues of Paralympic Games (PG) were held, the heat island effect was highly expected to cause heat-related illnesses in the outdoor venues with maximum temperatures exceeding 35°C. However, the actual number of heat-related illness cases during the competition was lower than that was initially expected, and it was unclear under what conditions or environment-related heat illnesses occurred among athletes. Object: To clarify the cause and factors contributing to the occurrence of heat-related illness among athletes participating in the Tokyo 2020 Olympic and Paralympic Games. Method: This retrospective descriptive study included 15 820 athletes from 206 countries. From 21 July 2021 to 8 August 2021 for the Olympics, and from 24 August 2021 to 5 September 2021 for the Paralympics. The number of heat-related illness cases at each venue, the incidence rate for each event, gender, home continent, as well as the type of competition, environmental factors (such as venue, time, location and wet-bulb globe temperature (WBGT)), treatment factor and the type of competition were analysed. Results: More number of heat-related illnesses among athletes occurred at the OG (n=110, 76.3%) than at the PG (n=36, 23.7%). A total of 100 cases (100%) at the OG and 31 cases (86.1%) at the PG occurred at the outdoors venues. In the OG, a total of 50 cases (57.9%) occurred during the competition of marathon running and race walking at Sapporo Odori Park. Six of those, were diagnosed with exertional heat illness and treated with cold water immersion (CWI) at OG and one case at PG. Another 20 cases occurred in athletics (track and field) competitions at Tokyo National Olympic Stadium. In total, 10 cases (10.0%) were diagnosed with severe heat illness in the OG and 3 cases (8.3%) in the PG. Ten cases were transferred to outside medical facilities for further treatment, but no case has been hospitalised due to severe condition. In the factor analysis, venue zone, outdoor game, high WBGT (<28°C) and endurance sports have been found to have a higher risk of moderate and severe heat-related illness (p<0.05). The incidence rate and severity could be attenuated by proper heat-related illness treatment (CWI, ice towel, cold IV transfusion and oral hydration) reduced the severity of the illness, providing summer hot environment sports. Conclusion: The Tokyo 2020 Olympic and Paralympic summer games were held. Contrary to expectations, we calculated that about 1 in 100 Olympic athletes suffered heat-related illness. We believe this was due to the risk reduction of heat-related illness, such as adequate prevention and proper treatment. Our experience in avoiding heat-related illness will provide valuable data for future Olympic summer Games.

The Tokyo 2020 Olympic and Paralympic pharmacy services during the COVID-19 pandemic.

BACKGROUND: During the Tokyo 2020 Games, pharmacists were required to provide appropriate pharmacotherapeutic care to athletes and officials at the polyclinic. Owing to the worldwide COVID-19 pandemic that was prevalent at the Games, it was imperative to strengthen infection control measures in the setting of such a major sporting event and to prevent and minimize the spread of COVID-19. OBJECTIVE: This study reports on the COVID-19 infection control measures and services provided by the pharmacy at the Tokyo 2020 Games. By evaluating pharmacy operations that took place under the COVID-19 protocol, this study provides insights for the organization of future sporting events, specifically their medical facilities. METHODS: Infection control measures in the pharmacy were implemented in accordance with the manual for dealing with COVID-19 infections. The number and content of issued and dispensed prescriptions were obtained from the electronic medical records and pharmacy department systems. These data were compared with those of the London 2012 Games, which were used as a reference for the pharmacy operations at the Tokyo 2020 Games. RESULTS: The participating pharmacists were fully trained in infection control measures. The number of prescriptions issued during the Olympics and Paralympics were 1120 and 1022, respectively. Prescriptions issued at the fever clinic accounted for 4% of the total number (77/2142). No influenza antiviral medications were prescribed, though medications to alleviate cold-like symptoms were issued. Compared to the London 2012 Games, there was a decrease (-59%) in the number of prescriptions. CONCLUSION: The positive impact of COVID-19 infection control measures was evident. The volume of prescriptions at the Tokyo 2020 Games was lower than that at the London 2012 Games. It was inferred that this was due to thorough infection control measures as well as enhanced pre-entry medical checkups before entering Japan, which reduced the incidence of diseases.

An international study on attitudes and opinions regarding female sports medicine physicians during pregnancy and the postpartum period.

OBJECTIVES: Supporting female sports medicine physicians to simultaneously be mothers and pursue professional careers is crucial to maintain gender diversity in sports medicine physicians. The purpose of this study is to understand the attitudes toward female sports medicine physicians during pregnancy and postpartum. METHODS: An anonymous online survey was distributed to sports medicine physicians practicing in 51 different countries. They were asked how comfortable they felt with female sports medicine physicians working on the sidelines of sporting events during pregnancy, if the female sports medicine physicians were as productive as their male counterparts after giving birth, and how satisfied they were with the percentage of female sports medicine physicians in their country. Data were analyzed using the chi-square test, and multivariate logistic regression analysis was performed to identify independent variables. RESULTS: In total, 1193 physicians (380 [31.9%] female) were included for analysis. Physicians in Asia were the least comfortable with pregnant sports medicine physicians working on the sidelines and those in North America were the most comfortable (odds ratio = 0.28 and 2.51, 95% confidence interval 0.18-0.44 and 1.55-4.06, respectively). More experienced sports medicine physicians (odds ratio = 1.01, 95% confidence interval 1.00-1.03; p < 0.05) and divorced physicians (odds ratio = 0.33, 95% confidence interval 0.12-0.91; p < 0.05) were less comfortable with pregnant female sports medicine physicians working on sidelines, and those trained in orthopedics were less likely to agree that female sports medicine physicians were equally as productive as male counterparts postpartum (odds ratio = 0.29, 95% confidence interval 0.10-0.88; p < 0.05). Female physicians were less satisfied with the percentage of female sports medicine physicians in their country (odds ratio = 0.41, 95% confidence interval 0.27-0.60; p < 0.01) than their male counterparts. CONCLUSIONS: Female sports medicine physicians may experience bias in their practice during pregnancy and postpartum.

Changes in the skin characteristics associated with dehydration and rehydration.

The present study aimed to test the hypothesis that changes in the dermal tissue dielectric constant (TDC) and biomechanical properties of the skin would be correlated with the indicators related to dehydration. Ten healthy adult men were enrolled in three trials: no fluid intake (DEH), ad libitum fluid intake (AL-HYD), and programmed fluid intake (P-HYD) after exercise in a randomised crossover design. The participants performed a pedalling exercise at 60% heart rate reserve until 2% body mass loss. At 120 min after exercise, an incremental exercise test was carried out. Aerobic capacity, body composition, TDC, biomechanical properties of the skin (pliability, viscoelasticity, and total recovery), and indicators related to dehydration in the serum and urine were measured before and 120 min after exercise. Higher values of the pliability and viscoelasticity, and lower value of the total recovery on the hand were demonstrated in the P-HYD trial compared to the DEH trial (all P < 0.05). Changes in the TDC were significantly correlated with changes in body mass, total body water, serum osmolarity, and hematocrit (all P < 0.05). Changes in the biomechanical properties of the hand were significantly correlated with changes in body mass, hematocrit, and urine specific gravity (all P < 0.05). The present study showed that the changes in skin characteristics correlated with the body water and dehydration-associated indicators in the serum and urine, thus suggesting that skin characteristics may be useful in the assessment of dehydration.HighlightsThis study was the first to investigate the effect of dehydration and rehydration on the TDC and biomechanical properties of the skin upon instrumental measure, and not manual testing.This study confirmed the decline in aerobic capacity by dehydration and immediate recovery with sufficient rehydration.Changes in the TDC and the biomechanical properties of the skin correlated with the body water and dehydration-associated indicators in the serum and urine.Skin characteristics may be useful in the assessment of dehydration.

IOC consensus statement on recommendations and regulations for sport events in the heat.

This document presents the recommendations developed by the IOC Medical and Scientific Commission and several international federations (IF) on the protection of athletes competing in the heat. It is based on a working group, meetings, field experience and a Delphi process. The first section presents recommendations for event organisers to monitor environmental conditions before and during an event; to provide sufficient ice, shading and cooling; and to work with the IF to remove regulatory and logistical limitations. The second section summarises recommendations that are directly associated with athletes' behaviours, which include the role and methods for heat acclimation; the management of hydration; and adaptation to the warm-up and clothing. The third section explains the specific medical management of exertional heat stroke (EHS) from the field of play triage to the prehospital management in a dedicated heat deck, complementing the usual medical services. The fourth section provides an example for developing an environmental heat risk analysis for sport competitions across all IFs. In summary, while EHS is one of the leading life-threatening conditions for athletes, it is preventable and treatable with the proper risk mitigation and medical response. The protection of athletes competing in the heat involves the close cooperation of the local organising committee, the national and international federations, the athletes and their entourages and the medical team.

Effects of Intestinal Bacterial Hydrogen Gas Production on Muscle Recovery following Intense Exercise in Adult Men: A Pilot Study.

This study aimed to examine the effects of hydrogen gas (H2) produced by intestinal microbiota on participant conditioning to prevent intense exercise-induced damage. In this double-blind, randomized, crossover study, participants ingested H2-producing milk that induced intestinal bacterial H2 production or a placebo on the trial day, 4 h before performing an intense exercise at 75% maximal oxygen uptake for 60 min. Blood marker levels and respiratory variables were measured before, during, and after exercise. Visual analog scale scores of general and lower limb muscle soreness evaluated were 3.8- and 2.3-fold higher, respectively, on the morning after treatment than that before treatment during the placebo trial, but not during the test beverage consumption. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations and production rates significantly increased with placebo consumption; no changes were observed with test beverage consumption. After exercise, relative blood lactate levels with H2-producing milk consumption were lower than those with placebo consumption. A negative correlation was observed between the variation of 8-OHdG and the area under the curve (AUC) of breath H2 concentrations. Lipid oxidation AUC was 1.3-fold higher significantly with H2-producing milk than with placebo consumption. Conclusively, activating intestinal bacterial H2 production by consuming a specific beverage may be a new strategy for promoting recovery and conditioning in athletes frequently performing intense exercises.

A Study of Race Pacing in the Running Leg of the Japan University Triathlon Championship.

Choosing an appropriate pacing strategy is important for good triathlon performance. In the Japan Student Triathlon Championship held in 2020, the men's category was divided into two groups, which was a different racing style from the previous races that all athletes start at the same time. It is highly likely that the performance level will vary as grouping was performed according to the competence of each player. The aim of this study was to understand the relationship of the total time and time of each leg between the superior performance group and the inferior performance group, as well as the difference in pacing during running in participants of the 2020 Japan University Triathlon Championship Watarase Competition, which was held under unconventional conditions. We analyzed 153 male athletes (Group A: 77; Group B: 76) who completed the race. The total race time, leg time, and average speed in each leg and its variation coefficient were evaluated based on the official results of the competition and footage recorded during the race. The results showed that the total time and leg time for each leg were significantly shorter in Group A compared to those in Group B (p < 0.05). In both groups, the Lap 4 run was significantly slower than those of Laps 1-3 (p < 0.05), while there was no significant difference in the running speed to average speed ratio across all laps between the groups (p < 0.05). Thus, there was a difference in running speed between the groups, but no significant difference in pacing. The results of this study serve as basic data for examining superior pacing strategies, although further studies on a wide range of competition levels are necessary.

Head Injury Assessment in the Elite Level Rugby Union in Japan: Review of 3 Seasons.

Head Injury Assessment (HIA) is the screening tool for head injury during a rugby game. The purpose of this study was to investigate the epidemiology of HIA in the Japan Rugby Top League (JRTL). The incidences of HIA, defined concussion (per 1,000 player-hours) and repeated concussions were evaluated in three seasons (2016-17, 2017-18, 2018-19; total 360 games). The HIA incidence rates were 12.7 (95% confidence interval 9.5-15.9), 20.8 (16.8-24.9), and 25.0 (20.5-29.5) in each season. HIA-1 criteria 2, which is applied for suspected concussion cases, was performed for 46 cases in the 2016-17 season, 81 cases in the 2017-18 season, and 88 cases in the 2018-19 season. The concussion incidence rates were significantly greater in the 2017-18 season (9.6/1000 player-hours, 95% confidence interval 6.8-12.4) and the 2018-19 season (14.4, 11-17.8) compared to the 2016-17 season (4.8, 2.8-6.8). The number of repeated concussion cases in the same season was 1 in the 2016-17 season and 4 in both the 2017-18 and 2018-19 seasons. This study confirmed significantly higher HIA and concussion incidence rates over time. Although the HIA system might have been established in the three seasons in JRTL, comprehensive management needs to be improved to prevent repeated concussions.

Gender bias in sports medicine: an international assessment of sports medicine physicians' perceptions of their interactions with athletes, coaches, athletic trainers and other physicians.

OBJECTIVES: To evaluate the difference between female and male sports medicine physicians regarding disrespectful attitudes and sexual harassment perceived from athletes, coaches, physicians, athletic trainers (ATs) and organisations/administrations. METHODS AND STUDY DESIGN: anonymous survey was distributed to sports medicine physicians practicing in 51 countries. χ2 analysis was used to detect differences between female and male sports medicine physicians and logistic regression analysis was used to determine the independent variables that affect disrespectful attitudes and sexual harassment from sports participants. RESULTS: 1193 sports medicine physicians (31.9% female) participated from 51 countries. The survey revealed that female physicians, compared with male physicians, perceive significantly more disrespect or have their judgement questioned more by the following categories: male and female athletes, male and female coaches, female physicians with more years of experience, male physicians (regardless of years of experience), male and female ATs and organisation/administrations (all p<0.05). The only category where the frequency of disrespect was perceived equally by male and female physicians was during their interactions with female physicians who have the same or lesser years of experience. Female sports medicine physicians noted more sexual harassment than male physicians during interactions with male athletes, coaches, ATs and physicians (all p<0.001). In the logistic regression, gender was a related factor for perceiving disrespect, especially from male coaches (OR=2.01) and physicians with more years of experience (OR=2.18). CONCLUSIONS: Female sports medicine physicians around the world experience disrespectful attitudes, questioning of their judgement and are sexually harassed significantly more often than male counterparts.

Effects of lung volume and trigeminal nerve stimulation on diving response in breath-hold divers and non-divers.

PURPOSE: This study investigated the effects of lung volume and trigeminal nerve stimulation (TS) on diving responses in breath-hold divers (BHDs) and non-divers (NDs). METHODS: Eight BHDs and nine NDs performed four breath-hold trials at different lung volumes, with or without TS, and one trial of TS. Haemodynamic parameters and electrocardiograms were measured for each trial. RESULTS: During the TS trial, the total peripheral resistance increased more in BHDs. Breath-hold performed at total lung capacity showed a more pronounced decrease in stroke volume and cardiac output in BHDs. The decrease in heart rate and increase in total peripheral resistance were more pronounced in BHDs when breath-holding was performed with TS. CONCLUSION: The more pronounced diving response in BHDs was attributed to the greater increase in total peripheral resistance caused by TS. Furthermore, the lower stroke volume and cardiac output in BH performed at total lung capacity could also cause a more pronounced diving response in BHDs.

Dicer-mediated miRNA processing is not involved in controlling muscle mass during muscle atrophy.

Muscle atrophy occurs in a variety of physiological and pathological conditions. Specific molecular networks that govern protein synthesis and degradation play important roles in controlling muscle mass under diverse catabolic states. MicroRNAs (miRNAs) were previously found to be regulators of protein synthesis and degradation, and their expressions in skeletal muscle were altered in muscle wasting conditions. However, functional roles of miRNAs in muscle atrophy are poorly understood. In this study, we generated tamoxifen-inducible Dicer knockout (iDicer KO) mice and subjected them to 2 weeks of single hindlimb denervation. The expression of Dicer mRNA was significantly reduced in muscle of the iDicer KO mice compared to that of WT mice. The loss of Dicer moderately reduced levels of muscle-enriched miRNAs, miR-1, miR-133a and miR-206 in both innervated and denervated muscles of the iDicer KO mice. We also found that the extent of denervation-induced muscle atrophy as well as changes of signaling molecules related to protein synthesis/degradation pathways in the iDicer KO mice were comparable to these in WT mice. Taken together, Dicer knockout in adult skeletal muscle did not affect denervation-induced muscle atrophy.

Bone parameters of elite athletes with oligomenorrhea and prevalence seeking medical attention: a cross-sectional study.

INTRODUCTION: Since the definition of secondary amenorrhea is cessation of regular menses for more than 3 months, it is likely that athletes with irregular menstrual cycles, including oligomenorrhea, do not consider the condition as serious. However, the consequences of untreated oligomenorrhea have not been investigated in elite track and field athletes. MATERIALS AND METHODS: The cohort consisted of 91 elite-level track and field athletes. Body compositions, including bone parameters and bone turnover markers (BTMs), were measured. RESULTS: Among the 91 participants, 52 were eumenorrheic and 33 were oligomenorrheic. The eumenorrheic athletes had significantly higher bone mineral density (BMD) and bone mineral content (BMC) of the lumbar spine, lower extremities, and whole body than had the oligomenorrheic athletes (p < 0.01). There were no significant differences in BTMs between the two groups, but oligomenorrheic athletes had significantly lower percent body fat. CONCLUSION: More than 40% of the elite-level female track and field athletes in this study reported menstrual disorders with oligomenorrhea as the most common. However, none sought medical attention. As compared to the eumenorrheic athletes, the oligomenorrheic athletes had lower BMC and BMD. Hence, if an athlete is oligomenorrheic, bone parameter measurements are considerably important.

Bone Metabolism, Bone Mineral Content, and Density in Elite Late Teen Female Sprinters.

With intensive training, bone injuries are a major concern for athletes. To assess bone condition, we often measure bone turnover markers, bone mineral content and density; however, in junior athletes, it is not easy to distinguish changes caused by bone injuries from those caused by growth, because the metabolism is increased in both cases. Moreover, although some studies have examined female endurance athletes, knowledge regarding changes in static and dynamic bone conditions in late teen athletes is limited. In this study, we measured the bone mineral content and density, as well as bone turnover markers, in 40 elite female sprinters in their late teens. Whole body mode dual-energy X-ray absorptiometry was performed to measure bone mineral content and density. Blood samples were collected to determine bone resorption and formation markers at the end of track season in 2016 and during the same period of the following year. Body weight and bone mineral content significantly increased, and tartrate-resistant acid phosphatase type 5b, bone-type alkaline phosphatase, and osteocalcin significantly decreased after a year. Furthermore, the rate of change in bone mineral content was higher in younger athletes, indicating that bone growth approaches completion in the late teen years and that bone metabolism accordingly decreases.

Prehospital management of exertional heat stroke at sports competitions: International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020.

OBJECTIVES: This document aimed to summarise the key components of exertional heat stroke (EHS) prehospital management. METHODS: Members of the International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020 summarised the current best practice regarding the EHS prehospital management. RESULTS: Sports competitions that are scheduled under high environmental heat stress or those that include events with high metabolic demands should implement and adopt policy and procedures for EHS prehospital management. The basic principles of EHS prehospital care are: early recognition, early diagnosis, rapid, on-site cooling and advanced clinical care. In order to achieve these principles, medical organisers must establish an area called the heat deck within or adjacent to the main medical tent that is optimised for EHS diagnosis, treatment and monitoring. Once admitted to the heat deck, the rectal temperature of the athlete with suspected EHS is assessed to confirm an elevated core body temperature. After EHS is diagnosed, the athlete must be cooled on-site until the rectal temperature is below 39°C. While cooling the athlete, medical providers are recommended to conduct a blood analysis to rule out exercise-associated hyponatraemia or hypoglycaemia, provided that this can be safely performed without interrupting cooling. The athlete is transported to advanced care for a full medical evaluation only after the treatment has been provided on-site. CONCLUSIONS: A coordination of care among all medical stakeholders at the sports venue, during transport, and at the hospital is warranted to ensure effective management is provided to the EHS athlete.