[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100660171":3},{"organization":4,"outcomesModule":7,"designInfo":19,"detailedDescription":28,"studyPopulation":18,"armGroups":29,"interventions":42,"overallOfficials":18,"centralContacts":52,"locations":58,"responsibleParty":74,"collaborators":18,"id":78,"slug":79,"hasResults":80,"nctId":81,"briefTitle":82,"officialTitle":83,"acronym":18,"eligibilityCriteria":84,"healthyVolunteers":85,"sex":86,"minAge":87,"maxAge":88,"enrollmentInfo":89,"targetDuration":18,"studyType":92,"phases":93,"briefSummary":95,"conditions":96,"keywords":99,"overallStatus":109,"whyStopped":18,"lastUpdateSubmitDate":110,"lastUpdatePostDateStruct":111,"startDateStruct":114,"completionDateStruct":116,"leadSponsor":118,"locationsCount":119},{"fullName":5,"class":6},"Capital University of Physical Education and Sports, China","OTHER",{"primaryOutcomes":8,"secondaryOutcomes":13,"otherOutcomes":18},[9],{"measure":10,"description":11,"timeFrame":12},"Average Nocturnal Total Sleep Time During the Intervention Period","Nocturnal total sleep time will be objectively measured using a wrist-worn activity monitor. Total sleep time is defined as the total number of minutes classified as sleep within the main nocturnal sleep period, excluding periods classified as wakefulness. The primary outcome will be calculated for each participant as the mean nocturnal total sleep time across valid target nights during the 3-week intervention period. Higher values indicate longer nocturnal sleep duration.","Throughout the 3-week intervention period, from Day 1 through Day 21",[14],{"measure":15,"description":16,"timeFrame":17},"Modified 505 Change-of-Direction Test Completion Time","Change-of-direction performance will be assessed using the modified 505 test under standardized conditions. Each participant will complete three valid trials, and the fastest valid completion time will be used as the outcome value. Completion time will be measured in seconds using electronic timing gates. Lower values indicate better change-of-direction performance.","Day 22, after the 3-week intervention",null,{"allocation":20,"interventionModel":21,"interventionModelDescription":22,"primaryPurpose":6,"observationalModel":18,"timePerspective":18,"maskingInfo":23},"RANDOMIZED","PARALLEL","Participants will be individually randomized in a 1:1 ratio to either a usual morning-training group starting at 7:00 AM or a delayed morning-training group starting at 9:00 AM. Participants will remain in their assigned parallel group throughout the 3-week intervention period. Randomization will be stratified by sex and recruitment batch using concealed variable block sizes of 2 or 4.",{"masking":24,"maskingDescription":25,"whoMasked":26},"SINGLE","Participants and coaches cannot be masked because the assigned morning-training start times are apparent. However, modified 505 test assessors and sleep-data scorers will be blinded to the actual group allocation and will have access only to participant study IDs and coded group labels (A\u002FB). Statistical analysts will also remain blinded to the correspondence between the coded labels and the actual intervention groups until data cleaning, protocol deviation classification, and the statistical analysis program have been finalized.",[27],"OUTCOMES_ASSESSOR","This study is a two-arm, parallel-group, individually randomized controlled trial designed to evaluate the effects of delaying morning training on sleep and change-of-direction performance in elite badminton athletes.\n\nThirty-eight athletes with a stable morning-training routine will be enrolled and randomly allocated in a 1:1 ratio to a usual morning-training group or a delayed morning-training group. Randomization will be stratified by sex and recruitment batch using concealed variable block sizes. The study will be conducted in two recruitment batches, with the second batch starting approximately four weeks after the first. Outcome assessors, sleep-data scorers, and statistical analysts will be blinded to the actual group allocation.\n\nBefore randomization, participants will complete health and injury screening, sleep-disorder risk screening, questionnaires, and a baseline monitoring period. Wrist-worn activity monitors will be used to objectively assess sleep. Participants will also complete sleep diaries documenting bedtime, sleep timing, nighttime awakenings, wake time, naps, device removal, caffeine and alcohol intake, medications or supplements, illness, pain, additional training, and other events that may affect sleep.\n\nDuring the 3-week intervention period, both groups will complete five morning-training sessions per week, for a total of 15 sessions. The usual morning-training group will begin training at 7:00 AM, whereas the delayed morning-training group will begin at 9:00 AM. Each morning session will last approximately 90 minutes. Apart from the assigned training start time, the two groups will follow the same daily training plan, including training content, duration, sets, rest intervals, venue, equipment, coaching arrangements, afternoon training, dietary principles, and recovery procedures.\n\nThe primary outcome will be objectively measured nocturnal total sleep time during the intervention period. The key secondary outcome will be change-of-direction performance assessed using the modified 505 test. The modified 505 test will be conducted before and after the intervention under standardized conditions. Each athlete will complete three valid trials, and the fastest valid completion time will be used as the main performance measure.\n\nAdditional sleep-related outcomes will include sleep opportunity, sleep efficiency, sleep onset latency, nighttime awakenings, bedtime, wake time, nap duration, and 24-hour total sleep. Training load, training adherence, session rating of perceived exertion, protocol deviations, injuries, and adverse events will also be recorded.\n\nThe primary analysis will follow the intention-to-treat principle. The primary sleep outcome will be compared between groups using analysis of covariance adjusted for baseline sleep duration, sex, and recruitment batch. The post-intervention modified 505 outcome will also be analyzed using analysis of covariance adjusted for baseline performance, sex, and recruitment batch. Repeated nightly sleep measurements will additionally be analyzed using linear mixed-effects models. Effect estimates will be reported with 95% confidence intervals.",[30,36],{"label":31,"type":32,"description":33,"interventionNames":34},"Usual Morning Training Group","ACTIVE_COMPARATOR","Participants assigned to the usual morning-training group will continue their regular morning-training schedule, beginning training at 7:00 AM. They will complete five morning-training sessions per week for three consecutive weeks, for a total of 15 sessions. Each session will last approximately 90 minutes. Training content, duration, sets, rest intervals, venue, equipment, coaching arrangements, afternoon training, dietary principles, and recovery procedures will be standardized and matched to those of the delayed morning-training group.",[35],"Behavioral: Usual Morning Training Schedule",{"label":37,"type":38,"description":39,"interventionNames":40},"Delayed Morning Training Group","EXPERIMENTAL","Participants assigned to the delayed morning-training group will begin morning training at 9:00 AM, representing a 120-minute delay compared with the usual 7:00 AM schedule. They will complete five morning-training sessions per week for three consecutive weeks, for a total of 15 sessions. Each session will last approximately 90 minutes. No mandatory roll call, early class, group activity, or other required task will be scheduled before the 9:00 AM training session. Training content, duration, sets, rest intervals, venue, equipment, coaching arrangements, afternoon training, dietary principles, and recovery procedures will otherwise be matched to those of the usual morning-training group.",[41],"Behavioral: Delayed Morning Training Schedule",[43,48],{"type":44,"name":45,"description":46,"armGroupLabels":47,"otherNames":18},"BEHAVIORAL","Usual Morning Training Schedule","Participants assigned to the usual morning-training group will begin each scheduled morning training session at 7:00 AM. The intervention will last for 3 consecutive weeks, with five morning-training sessions per week and 15 sessions in total. Each session will last approximately 90 minutes and will include standardized warm-up, badminton-specific technical training, footwork and change-of-direction exercises, multi-shuttle or tactical training, and cool-down. Training content, duration, workload, rest intervals, coaching arrangements, venue, diet, and recovery procedures will be matched to those of the delayed morning-training group.",[31],{"type":44,"name":49,"description":50,"armGroupLabels":51,"otherNames":18},"Delayed Morning Training Schedule","Participants assigned to the delayed morning-training group will begin each scheduled morning training session at 9:00 AM, representing a 120-minute delay from the usual 7:00 AM schedule. The intervention will last for 3 consecutive weeks, with five morning-training sessions per week and 15 sessions in total. Each session will last approximately 90 minutes and will follow the same standardized training content and workload as the usual morning-training group. No mandatory roll call, early class, group activity, or other required task will be scheduled before the 9:00 AM training session.",[37],[53],{"name":54,"role":55,"phone":56,"phoneExt":18,"email":57},"Tongwu Yu, PhD","CONTACT","+86 18101351378","18101351378@163.com",[59],{"facility":60,"status":18,"city":61,"state":62,"zip":63,"country":64,"countryCode":65,"cosmosGeoPoint":66,"geoPoint":71,"contacts":72},"Capital University of Physical Education and Sports","Beijing","Beijing Municipality","100191","China","CN",{"type":67,"coordinates":68},"Point",[69,70],116.39723,39.9075,{"lat":70,"lon":69},[73],{"name":54,"role":55,"phone":56,"phoneExt":18,"email":57},{"type":75,"investigatorFullName":76,"investigatorTitle":77,"investigatorAffiliation":5,"oldNameTitle":18,"oldOrganization":18},"PRINCIPAL_INVESTIGATOR","Tongwu Yu","Principal Investigator","100660171","delayed-morning-training-sleep-and-change-of-direction-performance-in-badminton-athletes-100660171",false,"NCT07873203","Delayed Morning Training, Sleep, and Change-of-Direction Performance in Badminton Athletes","Effects of Delaying the Start of Morning Training on Nocturnal Sleep and Change-of-Direction Performance in Badminton Athletes","Inclusion Criteria:\n\n* Elite badminton athletes receiving systematic professional badminton training and able to competently perform the modified 505 change-of-direction test.\n* A stable morning-training schedule during the previous 4 weeks.\n* Ability to maintain the same training phase, training location, and accommodation conditions throughout the study period.\n* Ability to complete baseline monitoring, the 3-week intervention, and pre- and post-intervention assessments.\n* Ability to understand the study procedures and willingness to provide written informed consent.\n\nExclusion Criteria:\n\n* Injury or musculoskeletal condition that prevents safe completion of maximal-effort change-of-direction testing.\n* Unstable cardiovascular, neurological, or other health conditions.\n* Deemed unsuitable for maximal-effort training or testing by sports medicine personnel.\n* Planned participation in a major competition, off-site training camp, or trans-time-zone travel during the study period.\n* A previously diagnosed sleep disorder.\n* Inability to comply with activity-monitor wear, sleep-diary completion, or assigned training-time requirements.",true,"ALL","18 Years","35 Years",{"count":90,"type":91},38,"ESTIMATED","INTERVENTIONAL",[94],"NA","This randomized controlled trial will investigate whether delaying the start of morning training from 7:00 AM to 9:00 AM improves nocturnal sleep and change-of-direction performance in elite badminton athletes. A total of 38 athletes with an established morning-training routine will be randomly assigned in a 1:1 ratio to either a usual morning-training group starting at 7:00 AM or a delayed morning-training group starting at 9:00 AM. Both groups will follow the same training content, duration, intensity, coaching arrangements, and recovery procedures for three weeks.\n\nNocturnal sleep will be objectively monitored using wrist-worn activity monitors, with total sleep time as the primary outcome. Change-of-direction performance will be assessed using the modified 505 test. Additional outcomes will include sleep opportunity, sleep efficiency, sleep onset latency, nighttime awakenings, bedtime and wake time, nap duration, 24-hour total sleep, training load, and training adherence.\n\nThe study aims to determine whether a later morning-training schedule can provide athletes with greater sleep opportunity without compromising training quality or physical performance.",[97,98],"Sleep Duration","Athletic Performance",[100,101,102,103,97,104,105,106,107,108],"Badminton","Elite Athletes","Morning Training","Training Start Time","Nocturnal Sleep","Change-of-Direction Performance","Modified 505 Test","Training Load","Sleep Monitoring","NOT_YET_RECRUITING","2026-10-09",{"date":112,"type":113},"2026-10-14","ACTUAL",{"date":115,"type":91},"2026-11-01",{"date":117,"type":91},"2027-01-30",{"name":5,"class":6},1]