Corrigendum: Investigation of supplement use and knowledge among Japanese elite athletes for the Tokyo 2020 Olympic/Paralympic Games and the Beijing 2022 Winter Olympic/Paralympic Games.

[This corrects the article DOI: 10.3389/fspor.2023.1258542.].

Investigation of supplement use and knowledge among Japanese elite athletes for the Tokyo 2020 Olympic/Paralympic games and the Beijing 2022 winter Olympic/Paralympic games.

Elite athletes frequently invest in the use of supplements to optimize their dietary regimens and enhance their athletic performance. However, unregulated and unplanned use of supplements can lead to adverse consequences, including anti-doping rule violations or health issues. Thus, athletes should verify their diets, consider scientific evidence, and take necessary precautions regarding supplements before use. To date, no study has explored whether athletes check these factors before using supplements. This study aimed to investigate supplement use using a questionnaire administered to 1,392 athletes (including candidate athletes) who participated in the Tokyo 2020 Olympic/Paralympic and Beijing 2022 Winter Olympic/Paralympic Games. Participants were categorized as follows: 1,040 participants in the Tokyo 2020 Olympic Games, 83 in the Tokyo 2020 Paralympic Games, 239 in the Beijing 2022 Winter Olympic Games, and 30 in the Beijing 2022 Winter Paralympic Games. We collected data on supplement use and gained further knowledge through interviews with the athletes. Approximately 70% of Tokyo 2020 Olympic/Paralympic and Beijing 2022 Winter Olympic athletes and approximately 50% of Beijing 2022 Winter Paralympians used supplements. Over 50% of athletes had not received a doctor's diagnosis or a dietitian's evaluation before supplement use. Moreover, only 50% of the athletes who used dietary supplements reviewed the scientific evidence for the dietary supplements before using them and justified their choice based on their own investigation, while those who did not use dietary supplements cited either a lack of need or fear of an anti-doping rule violation. Considering the holistic health and performance of athletes, as well as the risk associated with unregulated use, such as overdose and anti-doping rule violations, there is a need for nutritional education on supplement use for athletes and their entourages.

Magnetic resonance imaging findings related to sacroiliac joint pain in high-performance athletes.

BACKGROUND: Sacroiliac joint (SIJ) dysfunction in athletes affects competitiveness. However, the pathology and imaging features have not been clarified. OBJECTIVE: To clarify the association between SIJ pain and MRI findings in high-performance athletes. METHODS: Fifty-two Japanese high-performance athletes with or without SIJ pain were recruited. MRI short tau inversion recovery (STIR) semi-coronal and semi-axial images of their SIJs were taken. The relationships between high-signal changes in MRI-STIR and SIJ pain and pain duration were investigated. Six athletes with continuous SIJ pain were prospectively followed. RESULTS: The proportion of athletes with high-signal changes in the SIJ was significantly higher among athletes with SIJ pain for one month or more (76.9%, 10/13) than among athletes with SIJ pain for less than one month (18.2%, 2/11) and among athletes without SIJ pain (28.6%, 8/28). High-signal changes on painful SIJs were most often present in the sacrum. In three of the six athletes who were prospectively followed, the high-signal area and intensity on MRI both diminished as their symptoms improved. CONCLUSIONS: High-signal changes of the SIJ on MRI-STIR images in high-performance athletes may reflect their SIJ pain.

Lumbar Intervertebral Disc Degeneration Does Not Affect Muscle Synergy for Rowing Activities.

Rowers with disc degeneration may have motor control dysfunction during rowing. This study is aimed at clarifying the trunk and lower extremity muscle synergy during rowing and at comparing the muscle synergy between elite rowers with and without lumbar intervertebral disc degeneration. Twelve elite collegiate rowers (with disc degeneration, n = 6; without disc degeneration, n = 6) were included in this study. Midline sagittal images obtained by lumbar T2-weighted magnetic resonance imaging were used to evaluate disc degeneration. Participants with one or more degenerated discs were classified into the disc degeneration group. A 2000 m race trial using a rowing ergometer was conducted. Surface electrodes were attached to the right rectus abdominis, external oblique, internal oblique, latissimus dorsi, multifidus, erector spinae, rectus femoris, and biceps femoris. The activity of the muscles was measured during one stroke immediately after 20% and 80% of the rowing trial. Nonnegative matrix factorization was used to extract the muscle synergies from the electromyographic data. To compare the muscle synergies, a scalar product (SP) evaluating synergy coincidence was calculated, and the muscle synergies were considered identical at SP > 75%. Both groups had only one module in the 20% and 80% time points of the trial. At the 20% time point of the 2000 m rowing trial, the SP of the module was 99.8%. At the 80% time point, the SP of the module was 99.9%. The SP results indicate that, at 20% and 80% time points, both groups had the same module. The module showed a high contribution in all muscles. The activation coefficients indicated that the module was always highly activated throughout the rowing stroke in both groups. The trunk and lower extremity muscles are mobilized through the rowing stroke and maintain coordination during rowing. There was no difference in the muscle synergy between the rowers with and without lumbar intervertebral disc degeneration.

Mechanical loading influences the lumbar intervertebral disc. A cross-sectional study in 308 athletes and 71 controls.

There is evidence in animal populations that loading and exercise can positively impact the intervertebral disc (IVD). However, there is a paucity of information in humans. We examined the lumbar IVDs in 308 young athletes across six sporting groups (baseball, swimming, basketball, kendo, soccer, and running; mean age 19 years) and 71 nonathletic controls. IVD status was quantified via the ratio of IVD to vertebral body height (IVD hypertrophy) and ratio of signal intensity in the nucleus to that in the annulus signal (IVD nucleus hydration) on sagittal T2-weighted magnetic resonance imaging. P values were adjusted via the false discovery rate method to mitigate false positives. In examining the whole collective, compared to referents, there was evidence of IVD hypertrophy in basketball (P ≤ .029), swimming (P ≤ .010), soccer (P = .036), and baseball (P = .011) with greater IVD nucleus hydration in soccer (P = .007). After matching participants based on back-pain status and body height, basketball players showed evidence of IVD hypertrophy (P ≤ .043) and soccer players greater IVD nucleus hydration (P = .001) than referents. Greater career duration and training volume correlated with less (ie, worse) IVD nucleus hydration, but explained less than 1% of the variance in this parameter. In this young collective, increasing age was associated with increased IVD height. The findings suggest that basketball and soccer may be associated with beneficial adaptations in the IVDs in young athletes. In line with evidence on other tissues, such as muscle and bone, the current study adds to evidence that specific loading types may beneficially modulate lumbar IVD properties.

Injuries and physical characteristics affecting swimmer participation in the Olympics: A prospective survey.

OBJECTIVE: To identify injuries and physical characteristics affecting swimmers' performance. DESIGN: Prospective study. SETTING: Laboratory-based. PARTICIPANTS: Sixty-four Rio Olympic candidates (36 men, 28 women), who were high level swimmers ranked among the top 32 in the 2014 World Ranking in swimming. The participants were categorized into the Olympian group (n = 25), swimmers who were consecutively selected for the Olympic team, and the non-Olympian group (n = 39), swimmers who were not. MAIN OUTCOME MEASURES: Four months prior to the Olympic qualification in 2016, an orthopedist and two physical therapists evaluated injuries and 11 physical characteristics of the swimmers. The prevalence of total overuse injuries, shoulder and low back injury, and physical characteristics were compared between the two groups. RESULTS: The female swimmers in the non-Olympian group had a 53.3% prevalence of total overuse injuries, which was significantly higher than that of those in the Olympian group with 15.4% (p = 0.037). The prevalence of total over use injuries in male swimmers in both the Olympian and non-Olympian groups was 41.7%. Female Olympian group showed that the shoulder external rotation range of motion was significantly less than that of non-Olympian group (97.8 ± 5.7 and 103.6 ± 7.3, p = 0.046). CONCLUSIONS: In female swimmers, total overuse injuries four months before an important competition influence their performance at the event.

Injury trend analysis in the Japan national swim team from 2002 to 2016: effect of the lumbar injury prevention project.

OBJECTIVES: This study aimed to clarify the trends of injury occurrence in the Japan national swim team for 15 years and to evaluate the effectiveness of the lumbar injury prevention project. It also aimed to verify the incidence of swimming-related injuries among swimmers by sex, age and swimming style. METHODS: The target group comprised 488 swimmers who participated in the Olympics, Asian Games and Universiade from 2002 to 2016; we compiled data for the total number of injuries in each body part. The lumbar injury prevention project started in 2008 and included two components (deep trunk muscle exercises and evaluation of lumbar disc degeneration using MRI). We analysed the prevalence of lumbar injury before (2002-2008) and after (2009-2016) implementation of the lumbar injury prevention project by χ2 test. We compared age, sex and swim strokes between the injured and non-injured groups by χ2 test and unpaired t-test. RESULTS: The most common injury site was the lower back, followed by the shoulder and knee. The lumbar injury prevalence was significantly lower after implementation of the prevention project (23.5% vs 14.8%; p<0.05). Shoulder injuries were common in backstroke swimmers. The injury rate was significantly higher in female than in male swimmers. The injured group was significantly older than the non-injured group. CONCLUSIONS: Lumbar injury prevention intervention might be effective to prevent lower back injury in swimmers. Injury risk factors included female and old age; younger female athletes should prevent the development of injuries as they mature.

Stress fracture of the thoracic spine in an elite rhythmic gymnast: A case report.

Spondylolysis, a defect or stress fracture of the vertebral pars interarticularis, occurs most frequently in the lower lumbar spine and occasionally in the cervical spine, but is extremely rare in the thoracic spine. We report the case of a 17 year-old girl, an elite rhythmic gymnast, who reported with early-stage thoracic spondylolysis at T10 and T11 levels. Physicians should be aware that performance of unusual athletic movements, such as those by gymnasts, may lead to spondylolysis in rare locations.

Bacteremia with an iliopsoas abscess and osteomyelitis of the femoral head caused by Enterococcus avium in a patient with end-stage kidney disease.

A 70-year-old man on hemodialysis for end-stage kidney disease due to polycystic kidney disease presented with hip pain on extension and a high C-reactive protein level. Further examinations revealed an iliopsoas abscess and femoral head osteomyelitis caused by Enterococcus avium (E. avium) detected in blood and pus cultures. Complete resolution of the infection with ampicillin-resistant E. avium required six months of vancomycin therapy and two surgical drainage procedures. There have been no previous case reports in which both blood and abscess cultures confirmed E. avium infection. Careful attention should be paid to the detection of non-specific symptoms in patients on hemodialysis, with blood cultures being essential in such cases.

Relationship between low back pain and competitive sports activities during youth.

BACKGROUND: Low back pain is a significant problem not only for the adult, but also during youth. However, the relationship between low back pain during youth and the duration or types of competitive sports has not been clarified. HYPOTHESIS: Low back pain during youth is associated with the duration and types of competitive sports. STUDY DESIGN: Cross-sectional study; Level of evidence, 4. METHODS: Study participants were 4667 new university students who, from 2004 to 2006, answered a questionnaire concerning low back pain and their participation in competitive sports. The participants were divided into a "no" group (NO), a middle group (MID), and a high group (HI) based on the duration of participation in competitive sports. The answers to the questionnaire were analyzed using the Cochran-Mantel-Haenszel test. Furthermore, we selected students who had participated in the same sport for 5 or more years and categorized the students according to the type of sport. Differences in low back pain among the groups were analyzed using logistic regression with the NO group as the reference group. RESULTS: There were statistically significant linear associations in the NO, MID, and HI groups, with 50.0%, 61.8%, and 71.7%, respectively, of the students experiencing low back pain. Among the NO, MID, and HI groups, 4.4%, 5.7%, 9.6%, respectively, had experienced school absence due to low back pain; and 4.0%, 8.5%, and 14.6%, respectively had low back pain with associated lower extremity pain and numbness. All 8 sports groups that were analyzed had experienced low back pain significantly higher than the NO group, and the odds ratios differed by sport with the highest (3.8) for the volleyball group. CONCLUSION: Excessive exposure to competitive sports activities during youth was associated with low back pain and symptoms in the lower extremities, with the severity varying with the sport. To reduce low back pain in youth, factors that may be causing low back pain, such as sport-specific postures and motions, need to be investigated.

Lumbar intervertebral disk degeneration in athletes.

BACKGROUND: Several studies have reported that physical loading related to competitive sports activities is associated with lumbar intervertebral disk degeneration. However, the association between types of sports activities and disk degeneration has not been clarified. HYPOTHESIS: The frequencies of disk degeneration may vary with the competitive sport because of the different postures and actions specific to each sport. STUDY DESIGN: Cross-sectional study (prevalence); Level of evidence, 3. METHODS: Study participants were 308 well-trained university athletes (baseball players, basketball players, kendo competitors, runners, soccer players, swimmers) and 71 nonathlete university students (reference group). Disk degeneration was evaluated using T2-weighted magnetic resonance imaging. A self-reported questionnaire concerning low back pain was also conducted. RESULTS: The proportions of the participants who had disk degeneration among the baseball players (odds ratio, 3.23) and the swimmers (odds ratio, 2.95) were significantly higher than among the nonathletes using logistic regression analysis. When all patients were grouped together, the association between lifetime experience of low back pain and participants with disk degeneration was significant, and a linear association between the degree of severest low back pain experienced and participants with disk degeneration, analyzed by a Cochran-Mantel-Haenszel test, was also significant. CONCLUSION: Continuous competitive baseball and swimming activities during youth may be associated with disk degeneration. Furthermore, the study indicates that the experience of severe low back pain might be a predictor of disk degeneration in youth. The authors hope that preventive measures and management to protect against disk degeneration and low back pain in athletes will be established by further studies based on these results.

Factors associated with lumbar intervertebral disc degeneration in the elderly.

BACKGROUND CONTEXT: Lumbar intervertebral disc degeneration (DD) precedes degenerative diseases of the lumbar spine. Various factors in addition to normal aging are reported to be associated with DD, and recently atherosclerosis and risk factors for cardiovascular diseases (cardiovascular risk factors) have received much attention; however, the links between these risk factors and DD are unclear. PURPOSE: By correlating magnetic resonance images (MRI) with suspected degenerative disc risk factors such as obesity, cardiovascular risk factors, and atherosclerosis, we hope to clarify the factors associated with DD. STUDY DESIGN/SETTING: An observational study. PATIENT SAMPLE: Two hundred seventy adults (51-86 years old) who participated in a health promotion program. OUTCOME MEASURES: DD evaluated based on the signal intensity of MR T2-weighted mid-sagittal images of the lumbar spine. METHODS: Age, gender, body mass index (BMI), low-density lipoprotein cholesterol (LDLc), triglyceride (TG), glycosylated hemoglobin (HbA(1c)), brachial-ankle pulse wave velocity (baPWV) as an index of atherosclerosis, osteo-sono-assessment index (OSI) calculated from quantitative ultrasound assessment of the calcaneus as an index of bone mineral density (BMD), history of low back pain (LBP), smoking and drinking habits, and physical loading related to occupations and sports were assessed. The univariate relationships between DD and the variables were evaluated, and finally, odds ratios (OR) and 95% confidence intervals (CI) for the associations of each factor with DD were calculated using logistic regression at each disc level. RESULTS: Aging correlated significantly with DD of L1/2 (OR, 2.14), L2/3 (OR, 3.56), L3/4 (OR, 2.84), and L4/5 (OR, 3.05); high BMI, with L2/3 (OR, 2.98), L3/4 (OR, 3.58), L4/5 (OR, 2.32), and L5/S1 (OR, 3.34); high LDLc, with L4/5 (OR, 2.65); occupational lifting, with L1/2 (OR, 4.25); and sports activities, with L5/S1 (OR, 3.36). CONCLUSIONS: Aging, high BMI, high LDLc, occupational lifting, and sports activities are associated with DD. The results of this study raise our index of suspicion that cardiovascular risk factors and particular physical loading may contribute to DD; however additional studies are required to further investigate associations between DD and these factors.

Lumbar intervertebral disk degeneration in elite competitive swimmers: a case control study.

BACKGROUND: The majority of orthopaedic problems experienced by competitive swimmers are related to pain in the shoulder, low back, and knee. Three of 39 national swim team members were hampered in their performance due to lumbar disk herniation at an international competition in 2001. There has been no previous research into lumbar disk degeneration in elite competitive swimmers. HYPOTHESIS: Excessive competitive swimming activities accelerate lumbar disk degeneration. STUDY DESIGN: Case control study; Level of evidence, 3. METHODS: Fifty-six elite swimmers (high-load group, 35 men and 21 women; mean age, 19.6 years) and a control group of 38 university recreational level swimmers (low-load group, 24 men and 14 women; mean age, 21.1 years) were evaluated for lumbar disk degeneration using magnetic resonance imaging. We compared the prevalence of disk degeneration and the disk level between the 2 groups and further investigated the relationship among their symptoms, swimming styles, and disk degeneration. RESULTS: Thirty-eight (68%) elite swimmers and 11 (29%) controls had degenerated disks at various disk levels, and the prevalence was significantly greater in the elite swimmers (P = .0002). Comparison between the 2 groups of the prevalence of disk degeneration at each level revealed that the disk level of L5-S1 was significantly more frequently degenerated in the high-load group (P = .026). There was no significant relationship observed among the variables of low back pain symptoms, swimming strokes, and disk degeneration. CONCLUSION: Excessive competitive swimming activities might exaggerate lumbar intervertebral disk degeneration, especially in the L5-S1 intervertebral segment.