[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100658817":3},{"organization":4,"outcomesModule":7,"designInfo":77,"detailedDescription":88,"studyPopulation":82,"armGroups":89,"interventions":111,"overallOfficials":129,"centralContacts":133,"locations":139,"responsibleParty":159,"collaborators":82,"id":161,"slug":162,"hasResults":163,"nctId":164,"briefTitle":165,"officialTitle":166,"acronym":82,"eligibilityCriteria":167,"healthyVolunteers":168,"sex":169,"minAge":170,"maxAge":171,"enrollmentInfo":172,"targetDuration":82,"studyType":175,"phases":176,"briefSummary":178,"conditions":179,"keywords":182,"overallStatus":142,"whyStopped":82,"lastUpdateSubmitDate":194,"lastUpdatePostDateStruct":195,"startDateStruct":198,"completionDateStruct":200,"leadSponsor":202,"locationsCount":203},{"fullName":5,"class":6},"St. Louis University","OTHER",{"primaryOutcomes":8,"secondaryOutcomes":17,"otherOutcomes":64},[9,13],{"measure":10,"description":11,"timeFrame":12},"Running Economy (VO₂) During the Fixed-Pace 5 km Treadmill Run","Running economy will be assessed using oxygen consumption (VO₂) measured by indirect calorimetry during standardized portions of the fixed-pace 5 km treadmill run. Within-participant running-economy responses will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.","During the fixed-pace 5 km treadmill run at each of the four experimental visits, approximately 45 minutes after supplement\u002Fplacebo ingestion.",{"measure":14,"description":15,"timeFrame":16},"Heart-Rate Drift During the Fixed-Pace 5 km Treadmill Run","Heart-rate drift will be assessed from continuous heart-rate monitoring as the change in heart rate over the course of the fixed-pace 5 km treadmill run. Within-participant heart-rate drift will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.","Throughout the fixed-pace 5 km treadmill run at each of the four experimental visits, approximately 45 minutes after supplement\u002Fplacebo ingestion.",[18,22,25,29,32,36,40,43,47,50,54,57,60],{"measure":19,"description":20,"timeFrame":21},"Mean Oxygen Consumption (VO₂) During the Fixed-Pace 5 km Treadmill Run","Oxygen consumption (VO₂) will be measured continuously by indirect calorimetry and summarized as the mean body-mass-normalized VO₂ (mL\u002Fkg\u002Fmin) during the fixed-pace 5 km treadmill run. Within-participant mean VO₂ will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.","During the fixed-pace 5 km treadmill run at each of the four experimental visits, beginning approximately 45 minutes after supplement\u002Fplacebo ingestion.",{"measure":23,"description":24,"timeFrame":21},"Mean Carbon Dioxide Production (VCO₂) During the Fixed-Pace 5 km Treadmill Run","Carbon dioxide production (VCO₂) will be measured continuously by indirect calorimetry and summarized as the mean VCO₂ (L\u002Fmin) during the fixed-pace 5 km treadmill run. Within-participant mean VCO₂ will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.",{"measure":26,"description":27,"timeFrame":28},"Ventilation","Pulmonary ventilation will be measured using indirect calorimetry during the fixed-pace 5 km treadmill run and compared across supplement conditions.","During the fixed-pace 5 km treadmill run at each of the four experimental visits.",{"measure":30,"description":31,"timeFrame":28},"Respiratory Exchange Ratio","Respiratory exchange ratio (RER), calculated from oxygen consumption and carbon dioxide production, will be evaluated during the fixed-pace 5 km treadmill run and compared across supplement conditions.",{"measure":33,"description":34,"timeFrame":35},"1-Minute Heart-Rate Recovery After the Fixed-Pace 5 km Treadmill Run","Heart-rate recovery will be calculated as the decrease in heart rate from the end of the fixed-pace 5 km treadmill run to 60 seconds after exercise cessation, expressed in beats per minute. Within-participant 1-minute heart-rate recovery will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.","From exercise cessation to 60 seconds after completion of the fixed-pace 5 km treadmill run at each of the four experimental visits.",{"measure":37,"description":38,"timeFrame":39},"Capillary Blood Lactate Concentration","Capillary blood lactate concentration will be measured using finger-prick blood sampling and a point-of-care analyzer before and after exercise. Pre- to post-exercise responses will be compared across supplement conditions.","Immediately before and immediately after the fixed-pace 5 km treadmill run at each experimental visit.",{"measure":41,"description":42,"timeFrame":39},"Capillary Blood Ketone Concentration","Capillary blood ketone concentration will be measured using finger-prick blood sampling and a point-of-care analyzer before and after exercise. Pre- to post-exercise responses will be compared across supplement conditions.",{"measure":44,"description":45,"timeFrame":46},"Rating of Perceived Exertion","Rating of perceived exertion will be assessed using the Borg 6-20 Rating of Perceived Exertion scale, where 6 represents no exertion and 20 represents maximal exertion; higher scores indicate greater perceived exertion.","During and immediately following the fixed-pace 5 km treadmill run at each experimental visit.",{"measure":48,"description":49,"timeFrame":46},"Gastrointestinal Symptoms Severity","Gastrointestinal symptoms, including nausea, urge to vomit, bloating, belching, and abdominal cramping, will be assessed using visual analog scales anchored from no symptoms to the worst imaginable severity for each symptom. Higher values indicate greater symptom severity. Responses will be compared across the four supplement conditions.",{"measure":51,"description":52,"timeFrame":53},"Subjective Fatigue","Participant-reported fatigue will be assessed using a single-item 0-10 numeric rating scale, where 0 indicates no fatigue and 10 indicates extreme fatigue. Scores and within-visit changes will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.","Immediately before supplement\u002Fplacebo ingestion and immediately following the fixed-pace 5 km treadmill run at each experimental visit.",{"measure":55,"description":56,"timeFrame":53},"Subjective Energy Level","Participant-reported energy will be assessed using a single-item 0-10 numeric rating scale, where 0 indicates no energy at all and 10 indicates extremely high energy. Scores and within-visit changes will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.",{"measure":58,"description":59,"timeFrame":53},"Subjective Mental Focus","Participant-reported mental focus will be assessed using a single-item 0-10 numeric rating scale, where 0 indicates not at all focused and 10 indicates extremely focused. Scores and within-visit changes will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.",{"measure":61,"description":62,"timeFrame":63},"Participant-Reported Guess of Assigned Supplement Condition","Following each experimental visit, participants will report which supplement condition they believe they received. Responses will be summarized and compared with the actual assigned condition to evaluate participant perception of treatment assignment.","Immediately following completion of each experimental visit.",[65,69,73],{"measure":66,"description":67,"timeFrame":68},"Interstitial Glucose Response During the Experimental-Visit Window in the CGM Subgroup","Interstitial glucose will be measured continuously using continuous glucose monitoring in the prespecified randomly selected CGM subgroup. Only CGM data collected from the pre-supplement baseline through completion of the immediate post-exercise assessments at each experimental visit will be retained for analysis. Inter-visit CGM data will not be analyzed. Within-participant glucose responses will be compared across the caffeine, L-citrulline, exogenous ketone, and placebo conditions.","From pre-supplement baseline through completion of the immediate post-exercise assessments at each experimental visit.",{"measure":70,"description":71,"timeFrame":72},"Completion of All Four Experimental Visits","Feasibility will be assessed by the number and proportion of enrolled participants who complete all four randomized experimental visits and the full four-condition crossover protocol.","Across each participant's approximately 4-6 weeks of study participation.",{"measure":74,"description":75,"timeFrame":76},"Participants Experiencing Adverse Events","Adverse events and adverse responses occurring in association with study supplementation or exercise testing will be recorded throughout study participation. The number and proportion of participants experiencing one or more adverse events will be summarized.","From the first study visit through completion of the final study visit, approximately 4-6 weeks per participant.",{"allocation":78,"interventionModel":79,"interventionModelDescription":80,"primaryPurpose":81,"observationalModel":82,"timePerspective":82,"maskingInfo":83},"RANDOMIZED","CROSSOVER","Participants will be randomized in a 1:1:1:1 ratio to one of four treatment sequences using a four-period, four-treatment Williams square design (ABDC, BCAD, CDBA, DACB), where A = caffeine, B = L-citrulline, C = exogenous ketone, and D = placebo. This counterbalanced design balances treatment assignment across study periods and first-order carryover. Each participant will receive all four conditions and serve as their own control. Experimental visits will be separated by a minimum washout\u002Frecovery period of four days.","BASIC_SCIENCE",null,{"masking":84,"maskingDescription":85,"whoMasked":86},"SINGLE","Participants will be blinded to the assigned supplement condition at each experimental visit. Study beverages will use the same standardized vehicle and final volume, with identical or similar opaque containers used to support participant blinding when feasible. Complete taste matching cannot be guaranteed because the active supplements have different inherent tastes.",[87],"PARTICIPANT","This is a randomized, single-blind, placebo-controlled crossover study designed to compare acute physiological and perceptual responses to three pre-run nutritional supplements and placebo during a controlled fixed-pace 5 km treadmill run. Healthy, physically active runners will complete one screening\u002Fbaseline visit and four experimental visits. Each participant will complete all four experimental conditions in randomized order and will serve as their own control. A minimum washout\u002Frecovery period of four days will separate experimental visits.\n\nAt each experimental visit, participants will receive one of four pre-run conditions: caffeine at 4 mg\u002Fkg body weight, L-citrulline at 7 g, an exogenous ketone supplement providing 11.5 g beta-hydroxybutyrate (BHB), or placebo. Study products will be provided in a standardized beverage vehicle, followed by a 45-minute waiting period before the treadmill run.\n\nThe primary physiological outcomes of interest are running economy and heart-rate drift during the fixed-pace 5 km treadmill run. Additional outcomes include oxygen consumption, carbon dioxide production, ventilation, respiratory exchange ratio, heart-rate recovery, capillary blood lactate and ketone concentrations, rating of perceived exertion, gastrointestinal symptoms, subjective fatigue, energy, focus, and participant-reported perceptions of the assigned supplement condition.\n\nA prespecified randomly selected subgroup of up to 12 enrolled participants will use a Dexcom Stelo continuous glucose monitor during the experimental phase. CGM-derived glucose responses will be analyzed as exploratory outcomes within this subgroup only.\n\nThe study will also evaluate feasibility and tolerability, including visit completion, adverse events, supplement-related symptoms, gastrointestinal symptoms, and completeness of study measurements. The results are intended to characterize within-participant differences among the four conditions and provide preliminary data for future confirmatory studies.",[90,99,103,107],{"label":91,"type":92,"description":93,"interventionNames":94},"Sequence 1: Caffeine-L-Citrulline-Placebo-Ketone","EXPERIMENTAL","Participants assigned to this randomized crossover sequence will receive caffeine, followed by L-citrulline, placebo, and exogenous ketone across four experimental visits. Each intervention will be administered 45 minutes before a fixed-pace 5 km treadmill run. Experimental visits will be separated by a minimum washout\u002Frecovery period of four days.",[95,96,97,98],"Dietary Supplement: Caffeine","Dietary Supplement: L-Citrulline","Dietary Supplement: Exogenous Ketone (Beta-Hydroxybutyrate)","Other: placebo beverage",{"label":100,"type":92,"description":101,"interventionNames":102},"Sequence 2: L-Citrulline-Ketone-Caffeine-Placebo","Participants assigned to this randomized crossover sequence will receive L-citrulline, followed by exogenous ketone, caffeine, and placebo across four experimental visits. Each intervention will be administered 45 minutes before a fixed-pace 5 km treadmill run. Experimental visits will be separated by a minimum washout\u002Frecovery period of four days.",[95,96,97,98],{"label":104,"type":92,"description":105,"interventionNames":106},"Sequence 3: Ketone-Placebo-L-Citrulline-Caffeine","Participants assigned to this randomized crossover sequence will receive exogenous ketone, followed by placebo, L-citrulline, and caffeine across four experimental visits. Each intervention will be administered 45 minutes before a fixed-pace 5 km treadmill run. Experimental visits will be separated by a minimum washout\u002Frecovery period of four days.",[95,96,97,98],{"label":108,"type":92,"description":109,"interventionNames":110},"Sequence 4: Placebo-Caffeine-Ketone-L-Citrulline","Participants assigned to this randomized crossover sequence will receive placebo, followed by caffeine, exogenous ketone, and L-citrulline across four experimental visits. Each intervention will be administered 45 minutes before a fixed-pace 5 km treadmill run. Experimental visits will be separated by a minimum washout\u002Frecovery period of four days.",[95,96,97,98],[112,117,121,125],{"type":113,"name":114,"description":115,"armGroupLabels":116,"otherNames":82},"DIETARY_SUPPLEMENT","Caffeine","Caffeine will be administered at exactly 4 mg\u002Fkg body weight. The individualized dose will be calculated using body weight measured at the baseline visit. The commercially manufactured capsule contents will be weighed by trained study staff using a calibrated analytical balance to obtain the protocol-specified dose. Caffeine will be dispensed in the standardized study beverage and consumed 45 minutes before the fixed-pace 5 km treadmill run.",[91,100,104,108],{"type":113,"name":118,"description":119,"armGroupLabels":120,"otherNames":82},"L-Citrulline","L-citrulline will be administered at exactly 7.0 g. The commercially manufactured pure L-citrulline powder will be weighed using a calibrated analytical balance, dispensed in the standardized study beverage, and consumed 45 minutes before the fixed-pace 5 km treadmill run.",[91,100,104,108],{"type":113,"name":122,"description":123,"armGroupLabels":124,"otherNames":82},"Exogenous Ketone (Beta-Hydroxybutyrate)","The exogenous ketone condition will consist of one 15 g serving of Nutricost Ketone BHB Salt 4-in-1 Powder, providing 11.5 g beta-hydroxybutyrate (BHB) as calcium, magnesium, sodium, and potassium BHB salts. The supplement will be dispensed in the standardized study beverage and consumed 45 minutes before the fixed-pace 5 km treadmill run.",[91,100,104,108],{"type":6,"name":126,"description":127,"armGroupLabels":128,"otherNames":82},"placebo beverage","The placebo will be a study-prepared beverage containing water, food-grade lime flavoring, and stevia, with no active study supplement. It will use the same standardized final volume as the active conditions and will be consumed 45 minutes before the fixed-pace 5 km treadmill run.",[91,100,104,108],[130],{"name":131,"affiliation":5,"role":132},"Hossein Rafiei","PRINCIPAL_INVESTIGATOR",[134],{"name":135,"role":136,"phone":137,"phoneExt":82,"email":138},"Hossein Rafiei, PhD, RD, ACSM-CPT","CONTACT","314-977-8675","hossein.rafiei@health.slu.edu",[140],{"facility":141,"status":142,"city":143,"state":144,"zip":145,"country":146,"countryCode":147,"cosmosGeoPoint":148,"geoPoint":153,"contacts":154},"Saint Louis University, Allied Health Building","RECRUITING","St Louis","Missouri","63104","United States","US",{"type":149,"coordinates":150},"Point",[151,152],-90.19789,38.62727,{"lat":152,"lon":151},[155,157,158],{"name":156,"role":136,"phone":137,"phoneExt":82,"email":138},"Hossein Rafiei, PhD RD",{"name":82,"role":136,"phone":82,"phoneExt":82,"email":138},{"name":135,"role":132,"phone":82,"phoneExt":82,"email":82},{"type":132,"investigatorFullName":131,"investigatorTitle":160,"investigatorAffiliation":5,"oldNameTitle":82,"oldOrganization":82},"Assistant Professor","100658817","effects-of-pre-run-nutritional-supplements-during-a-fixed-pace-5-km-treadmill-run-100658817",false,"NCT07854223","Effects of Pre-Run Nutritional Supplements During a Fixed-Pace 5 km Treadmill Run","Fueling the Kilometers: Effects of Pre-Run Nutritional Supplements on Physiological Responses During a Fixed-Pace 5 km Treadmill Run","Inclusion Criteria:\n\n* Age 18-35 years\n* Healthy adult\n* Able to provide written informed consent\n* Regularly engaged in running-based aerobic training at least 3 times per week for at least 30 minutes per session during the past 3 months\n* Able to complete a 5 km run in under 30 minutes\n* Able and willing to comply with treadmill testing, fingerstick testing, dietary standardization, supplement restrictions, and pre-visit instructions\n* Participants randomly selected for the continuous glucose monitoring subgroup must also be willing to undergo Dexcom Stelo continuous glucose monitor placement and wear\n\nExclusion Criteria:\n\n* Known cardiovascular, metabolic, pulmonary, or neurological disease that may increase the risk associated with exercise testing or materially influence study outcomes\n* Uncontrolled hypertension or another cardiovascular condition that, in the investigator's judgment, makes vigorous treadmill exercise unsafe\n* Diagnosed type 1 or type 2 diabetes mellitus or another known metabolic disease that may materially influence study outcomes\n* Pregnant, breastfeeding, or planning pregnancy during the study period\n* Current use of nitrate medications or phosphodiesterase type 5 (PDE5) inhibitors, including sildenafil, tadalafil, or vardenafil\n* Known sensitivity or allergy to caffeine, L-citrulline, exogenous ketone\u002FBHB salt products, or any study beverage ingredient\n* Current use of stimulant medications or other medications that may significantly influence cardiovascular, blood pressure, or metabolic responses to exercise, as determined by the investigator\n* Musculoskeletal injury or condition that limits safe treadmill running\n* Smoking or regular use of nicotine products\n* Recent illness, surgery, or hospitalization that, in the opinion of the investigators, may interfere with safe participation or study outcomes\n* Unable or unwilling to comply with study procedures or pre-visit standardization requirements\n* Running fewer than 3 times per week or otherwise not meeting the running-training inclusion criterion",true,"ALL","18 Years","35 Years",{"count":173,"type":174},20,"ESTIMATED","INTERVENTIONAL",[177],"NA","This study will examine how three commonly used pre-run nutritional supplements-caffeine, L-citrulline, and an exogenous ketone supplement-affect physiological and perceptual responses during a fixed-pace 5 km treadmill run in healthy, physically active runners.\n\nParticipants will complete one screening and baseline visit followed by four experimental visits in a randomized order. At each experimental visit, participants will receive caffeine, L-citrulline, an exogenous ketone supplement, or placebo before completing a fixed-pace 5 km treadmill run. Each participant will receive all four conditions and will therefore serve as their own control.\n\nThe study will evaluate measures including running economy, heart-rate responses, oxygen consumption, respiratory measures, blood lactate and ketone concentrations, perceived exertion, gastrointestinal symptoms, fatigue, energy, and focus. A randomly selected subgroup will also wear a continuous glucose monitor to explore glucose responses during the experimental visits. The study will also assess the feasibility and tolerability of completing repeated treadmill trials under the four supplement conditions.",[180,181],"Exercise Physiology","Nutritional Supplementation",[183,184,114,118,185,186,187,188,189,190,191,192,193],"Running Economy","Heart Rate Drift","Exogenous Ketones","Beta-Hydroxybutyrate","5 km Running","Endurance Exercise","Nutritional Supplements","Indirect Calorimetry","Blood Lactate","Blood Ketones","Continuous Glucose Monitoring","2026-09-26",{"date":196,"type":197},"2026-10-02","ACTUAL",{"date":199,"type":174},"2026-10",{"date":201,"type":174},"2027-08",{"name":5,"class":6},1]