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Purpose: This study aimed to examine pacing strategies and identify the stroke that has the most significant impact on overall performance in men's and women's 200-m and 400-m individual-medley events from 2000 to 2021. Methods: The time in each lap and overall race was retrieved from the World Aquatics website. The standardized time for each stroke in individual medley was calculated by dividing the actual time by a reference time specific to each stroke. The reference time was derived from the respective laps in single-stroke finals in the 2017 World Swimming Championships. The decision-tree method was used for analysis. The dependent variables were qualified or nonqualified in heats and semifinals, and winning medals in finals. The independent variables were the ratio of standardized time in each stroke to the sum of standardized time in all 4 strokes. Results: Swimmers who spent a higher ratio of standardized time in the butterfly stroke (>0.236–0.245) are associated with a higher likelihood of winning medals or qualifying for the next stage in most men's and women's 200-m and 400-m individual medley. Butterfly exhibited the highest normalized importance that distinguished medalists from nonmedalists in the finals. The front-crawl stroke is the second most important determinant in medalists in men's and women's 200-m individual medley, whereas backstroke and breaststroke were the second most important in men's and women's 400-m individual medley, respectively. Conclusion: Individual-medley swimmers who were excellent in butterfly and conserved energy in butterfly had a higher likelihood of success. [ABSTRACT FROM AUTHOR]

Background: The long-term monitoring of internal and external training load is crucial for the training effectiveness of athletes. This study aims to quantify the internal and external training loads of collegiate male volleyball players during the competitive season. The internal and external training load variables were analyzed across mesocycles and playing positions. Methods: Fourteen participants with age of 20.2 ± 1.3 years, height of 1.81 ± 0.05 m, and body weight of 70.8 ± 5.9 kg were recruited. The data were collected over a 29-week period that was divided into four mesocycles: preparation 1 (P1, weeks 1–7), competition 1 (C1, weeks 8–14, including a 5-day tournament in week 14), preparation 2 (P2, weeks 15–23), and competition 2 (C2, weeks 24–29, including a 6-day tournament in week 29). Each participant wore an inertial measurement unit and reported the rating of perceived exertion in each training session. The internal training load variables included weekly session rating of perceived exertion, acute: chronic workload ratio, and training monotony and strain. The external training load variables included jump count and height and the percentage of jumps exceeding 80% of maximal height. Results: C2 had the highest average weekly internal training load (3022 ± 849 AU), whereas P2 had the highest average weekly acute: chronic workload ratio (1.46 ± 0.13 AU). The number of weekly jumps in C1 (466.0 ± 176.8) was significantly higher than in other mesocycles. Weekly jump height was significantly higher in C1, P2, and C2. Internal training load was positively correlated with jump count (ρ = 0.477, p < 0.001). Jump count was negatively correlated with jump height (ρ = −0.089, p = 0.006) and the percentage of jumps exceeding 80% of maximal height (ρ = −0.388, p < 0.001). The internal and external training load variables were similar among different playing positions. Conclusion: The participants exhibited significantly higher internal training load in C2 and higher jump height after P1. A high jump count was associated with higher internal training load and lower jump height. Excessive jumps may result in fatigue and reduce height. [ABSTRACT FROM AUTHOR]

Background: The Global Matrix 4.0 on physical activity (PA) for children and adolescents was developed to achieve a comprehensive understanding of the global variation in children's and adolescents' (5–17 y) PA, related measures, and key sources of influence. The objectives of this article were (1) to summarize the findings from the Global Matrix 4.0 Report Cards, (2) to compare indicators across countries, and (3) to explore trends related to the Human Development Index and geo-cultural regions. Methods: A total of 57 Report Card teams followed a harmonized process to grade the 10 common PA indicators. An online survey was conducted to collect Report Card Leaders' top 3 priorities for each PA indicator and their opinions on how the COVID-19 pandemic impacted child and adolescent PA indicators in their country. Results:Overall Physical Activity was the indicator with the lowest global average grade (D), while School and Community and Environment were the indicators with the highest global average grade (C+). An overview of the global situation in terms of surveillance and prevalence is provided for all 10 common PA indicators, followed by priorities and examples to support the development of strategies and policies internationally. Conclusions: The Global Matrix 4.0 represents the largest compilation of children's and adolescents' PA indicators to date. While variation in data sources informing the grades across countries was observed, this initiative highlighted low PA levels in children and adolescents globally. Measures to contain the COVID-19 pandemic, local/international conflicts, climate change, and economic change threaten to worsen this situation. [ABSTRACT FROM AUTHOR]

Acute body mass loss before competitions in combat sports usually leads to loss in fat-free mass. Beta-hydroxy-beta-methylbutyrate (HMB) has been shown to increase skeletal muscle mass and muscle strength in various muscle wasting conditions. This study investigated the effect of HMB supplementation on body composition and sport-specific performance in well-trained boxers consuming a hypocaloric diet. Twelve male college boxers were divided into the HMB and placebo (PLA) groups using a body weight-matched single-blind parallel design. The study comprised a 6-day weight loss period (days 1–6), followed by a 3-day competition period (days 7–9). The participants in both the groups consumed 16 kcal/kg/day, including 1.6–1.7 g/kg of carbohydrates, 1.2–1.3 g/kg of protein, and 0.45–0.5 g/kg of fat during the 9-day period. The HMB group consumed 3 g/day HMB. Body composition measurement, isometric mid-thigh pull (IMTP), and a simulated boxing match were performed at baseline and on days 7, 8, and 9. Fasting blood samples were collected on the day before day 1 and on days 7, 8, and 9. Body mass was significantly decreased after the 6-day weight loss period (HMB group: baseline: 69.4 ± 11.2 kg, day 7: 67.1 ± 11.2 kg; PLA group: baseline: 68.6 ± 12.1 kg, day 7: 65.7 ± 11.5 kg, P < 0.05) while it was unchanged on the 3-day competition period in both the groups. Fat-free mass in the HMB group was maintained throughout the 9-day period (baseline: 56.7 ± 9.3 kg, day 7: 56.3 ± 8.7 kg, day 9: 55.8 ± 9.5 kg) whereas it significantly decreased on days 7 and 9 compared to the baseline in the PLA group (baseline: 55.2 ± 6.4 kg, day 7: 54.1 ± 6.6 kg, day 9: 54.0 ± 6.6 kg, P < 0.05). In the PLA group, the average and maximal heart rates in round 1 and the average heart rate in round 2 on days 8 and 9 were significantly lower than those at baseline, while these parameters were unchanged in the HMB group. The maximal force and the rate of force development in the IMTP remained unchanged among the different timepoints in both the groups. The blood biochemical parameters were similar at any timepoint between the PLA and HMB groups. HMB supplementation during acute weight loss may preserve fat-free mass and maintain heart rate response in subsequent simulated matches in well-trained boxers. In addition, HMB supplementation had a nonsignificant effect on glucose, fat, and protein metabolism during energy restriction. [ABSTRACT FROM AUTHOR]

Context: An experimental Health Care Improvement Program (HCIP) was initiated by the Bureau of National Health Insurance in 1997 to improve the accessibility of health care in several rural, mountainous districts. Purpose: This longitudinal study evaluated service availability, utilization patterns, and effectiveness of services under the HCIP in the A-Li Mountain District. Methods: Outpatient claims made by residents in the A-Li Mountain District were extracted from the database of the National Health Insurance program. Changes in utilization pattern and volume were analyzed. Satisfaction levels were assessed by 2-stage face-to-face interviews with local residents. Findings: After the HCIP, the average population served by each doctor decreased 75%, and total outpatient visits increased 15.4%. The total number of in-district outpatient visits increased 83.6%. The proportion of in-district outpatient visits to all visits increased from 22.1% to 35.1%. The total in-district outpatient visit fee claimed increased 100.2%, and the total out-of-district outpatient visit fee claimed increased only 7.2%. About 60.4% of the residents were not satisfied with overall health care services before the HCIP. The proportion decreased to 32.4% after the HCIP. Conclusions: The HCIP improved accessibility, enriched local medical care resources, changed the utilization pattern of some residents, and increased residents' satisfaction level. A well-managed program with stabilized financial resources is more likely to succeed if it also respects cultural differences and responds to community needs.

Background: Accumulating sufficient moderate to vigorous physical activity is recognized as a key determinant of physical, physiological, developmental, mental, cognitive, and social health among children and youth (aged 5–17 y). The Global Matrix 3.0 of Report Card grades on physical activity was developed to achieve a better understanding of the global variation in child and youth physical activity and associated supports. Methods: Work groups from 49 countries followed harmonized procedures to develop their Report Cards by grading 10 common indicators using the best available data. The participating countries were divided into 3 categories using the United Nations' human development index (HDI) classification (low or medium, high, and very high HDI). Results: A total of 490 grades, including 369 letter grades and 121 incomplete grades, were assigned by the 49 work groups. Overall, an average grade of "C-," "D+," and "C-" was obtained for the low and medium HDI countries, high HDI countries, and very high HDI countries, respectively. Conclusions: The present study provides rich new evidence showing that the situation regarding the physical activity of children and youth is a concern worldwide. Strategic public investments to implement effective interventions to increase physical activity opportunities are needed. [ABSTRACT FROM AUTHOR]

Background: To better understand the childhood physical inactivity crisis, Report Cards on physical activity of children and youth were prepared concurrently in 30 very high Human Development Index countries. The aim of this article was to present, describe, and compare the findings from these Report Cards. Methods: The Report Cards were developed using a harmonized process for data gathering, assessing, and assigning grades to 10 common physical activity indicators. Descriptive statistics were calculated after converting letter grades to interval variables, and correlational analyses between the 10 common indicators were performed using Spearman's rank correlation coefficients. Results: A matrix of 300 grades was obtained with substantial variations within and between countries. Low grades were observed for behavioral indicators, and higher grades were observed for sources of influence indicators, indicating a disconnect between supports and desired behaviors. Conclusion: This analysis summarizes the level and context of the physical activity of children and youth among very high Human Development Index countries, and provides additional evidence that the situation regarding physical activity in children and youth is very concerning. Unless a major shift to a more active lifestyle happens soon, a high rate of noncommunicable diseases can be anticipated when this generation of children reaches adulthood. [ABSTRACT FROM AUTHOR]

Fruits and vegetables have been known to contain a variety of antioxidant components. It has been suggested that antioxidants may protect biomolecules from oxidative damage and therefore be associated with reduced risks of cardiovascular disease and certain cancer. The antioxidant abilities of various parts of eight common fruits and vegetables produced in Taiwan were investigated, including tomato, guava, squash, tangerine, wax gourd, pineapple, chayote, and eggplant. Squash, wax gourd, tomato, and guava seeds showed the highest antioxidant activities in thiobarbituric acid assay. Wax guard and squash seeds showed the highest antioxidant activities in iodometric assay. At the level of 1 g fresh sample, low-density lipoprotein peroxidation was inhibited by at least 90% by tomato meat, guava meat, squash seed, wax gourd meat, core, and seed, and eggplant skin. The total phenolic content was significantly correlated with antioxidant activities measured by thiobarbituric acid (r= 0.715, P

Abstract Many athletes need to participate in multiple events in a single day. The efficient post-exercise glycogen recovery may be critical for the performance in subsequent exercise. This study examined whether post-exercise carbohydrate supplementation could restore the performance in the subsequent simulated wrestling match. The effect of branched-chain amino acids and arginine on glucose disposal and performance was also investigated. Nine well-trained male wrestlers participated in 3 trials in a random order. Each trial contained 3 matches with a 1-hr rest between match 1 and 2, and a 2-hr rest between match 2 and 3. Each match contained 3 exercise periods interspersed with 1-min rests. The subjects alternated 10-s all-out sprints and 20-s rests in each exercise period. At the end of match 2, 3 different supplementations were consumed: 1.2 g/kg glucose (CHO trial), 1 g/kg glucose + 0.1 g/kg Arg + 0.1 g/kg BCAA (CHO+AA trial), or water (placebo trial). The peak and average power in the 3 matches was similar in the 3 trials. After the supplementation, CHO and CHO+AA trial showed significantly higher glucose and insulin, and lower glycerol and non-esterified fatty acid concentrations than the placebo trial. There was no significant difference in these biochemical parameters between the CHO and CHO+AA trials. Supplementation of carbohydrate with or without BCAA and arginine during the post-match period had no effect on the performance in the following simulated match in wrestlers. In addition, BCAA and arginine did not provide additional insulinemic effect.

Abstract The supplementation of sodium bicarbonate (NaHCO3) could increase performance or delay fatigue in intermittent high-intensity exercise. Prolonged tennis matches result in fatigue, which impairs skilled performance. The aim of this study was to investigate the effect of NaHCO3 supplementation on skilled tennis performance after a simulated match. Nine male college tennis players were recruited for this randomized cross-over, placebo-controlled, double-blind study. The participants consumed NaHCO3 (0.3 g. kg-1) or NaCl (0.209 g. kg-1) before the trial. An additional supplementation of 0.1 g. kg-1 NaHCO3 or 0.07 g. kg-1 NaCl was ingested after the third game in the simulated match. The Loughborough Tennis Skill Test was performed before and after the simulated match. Post-match [HCO3-] and base excess were significantly higher in the bicarbonate trial than those in the placebo trial. Blood [lactate] was significantly increased in the placebo (pre: 1.22 ± 0.54; post: 2.17 ± 1.46 mM) and bicarbonate (pre: 1.23 ± 0.41; post: 3.21 ± 1.89 mM) trials. The match-induced change in blood [lactate] was significantly higher in the bicarbonate trial. Blood pH remained unchanged in the placebo trial (pre: 7.37 ± 0.32; post: 7.37 ± 0.14) but was significantly increased in the bicarbonate trial (pre: 7.37 ± 0.26; post: 7.45 ± 0.63), indicating a more alkaline environment. The service and forehand ground stroke consistency scores were declined significantly after the simulated match in the placebo trial, while they were maintained in the bicarbonate trial. The match-induced declines in the consistency scores were significantly larger in the placebo trial than those in the bicarbonate trial. This study suggested that NaHCO3 supplementation could prevent the decline in skilled tennis performance after a simulated match.

Abstract Background Epidemiological surveillance of infectious diseases through the mandatory-reporting system is crucial in the planning and evaluation of disease control and prevention program. This study investigated the reporting behavior, knowledge, and attitude to reporting communicable disease in private doctors in Taiwan. The differences between the reporting and non-reporting doctors were also explored. Methods A total of 1250 clinics were randomly sampled nationwide by a 2-stage process. Data were collected from 1093 private doctors (87.4% response rate) using a self-administered structured questionnaire. Four hundred and six (37.2%) doctors reported having diagnosed reportable communicable diseases. Among them, 340 (83.5%) have the experiences of reporting. Results The most common reasons for not reporting were "do not want to violate the patient's privacy", "reporting procedure is troublesome", and "not sure whether the diagnosed disease is reportable". Significantly higher proportions of the non-reporting doctors considered the reporting system inconvenient or were not familiar with the system. The highest percentage (65.2%) of the non-reporting doctors considered that a simplified reporting procedure, among all measures, would increase their willingness to report. In addition, a significantly higher proportion of the non-reporting doctors would increase their willingness to report if there has been a good reward for reporting or a penalty for not reporting. Conclusion The most effective way to improve reporting rate may be to modify doctor's attitude to disease reporting. The development of a convenient and widely-accepted reporting system and the establishment of a reward/penalty system may be essential in improving disease reporting compliance in private doctors.