{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T11:25:00Z","timestamp":1777375500708,"version":"3.51.4"},"reference-count":47,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T00:00:00Z","timestamp":1777248000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFMK"],"abstract":"<jats:p>Background: Race walking, an Olympic discipline, produces an increase in energy cost and a change in the recruitment pattern of muscle fibres compared with running, yet the cardiorespiratory responses of elite race walkers to severe-intensity exercise remain poorly characterised. Objectives: (i) To determine whether exhaustive exercise performed at v\u039450 elicits VO2max in young elite race walkers, and (ii) to compare the temporal and metabolic profiles of this effort with those of similarly trained runners. Methods: Fourteen elite junior athletes (seven race walkers and seven runners) completed an incremental test to determine velocity at the lactate threshold (vLT), vVO2max, and VO2max, followed by a constant-velocity trial at individual v\u039450 performed to voluntary exhaustion on a 400 m track. Breath-by-breath VO2, heart rate, capillary blood lactate concentration, and time to exhaustion, time limit (Tlim) were measured. Results: At v\u039450 (\u224894% vVO2max), the race walkers reached VO2max, with no detectable VO2 slow component (SC) in six of seven participants. In contrast, runners exhibited a significant SC (8 \u00b1 3% of total VO2). The energy cost (EC) was 16% higher in race walking than in running (p &lt; 0.01). Conclusions: In elite junior race walkers, it seems that v\u039450 reliably elicits VO2max primarily due to a high baseline oxygen cost rather than a progressive VO2 SC, contrasting with the kinetic response observed in running. These discipline-specific responses suggest that interval training in race walking should be prescribed using walking-specific thresholds. This study is preliminary, given the small sample size; further studies with larger cohorts are warranted.<\/jats:p>","DOI":"10.3390\/jfmk11020174","type":"journal-article","created":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T07:49:36Z","timestamp":1777362576000},"page":"174","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["v\u039450 Race Walking: High Energetic Cost, Rapid VO2max, and No Slow Component"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4612-0502","authenticated-orcid":false,"given":"Laurence","family":"Mille-Hamard","sequence":"first","affiliation":[{"name":"Laboratoire Informatique, Bio-Informatique et Syst\u00e8mes Complexes (IBISC), Universit\u00e9 Paris-Saclay, 91034 Evry, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Murielle","family":"Garcin","sequence":"additional","affiliation":[{"name":"Univ. Lille, CNRS, UMR 9193, SCALab, Sciences Cognitives et Sciences Affectives, 59000 Lille, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0465-9016","authenticated-orcid":false,"given":"St\u00e9phane","family":"Dufour","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Translational Medicine Federation (FMTS), EA 3072, University of Strasbourg, 67000 Strasbourg, France"},{"name":"Faculty of Sport Sciences, University of Strasbourg, 67000 Strasbourg, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6085-998X","authenticated-orcid":false,"given":"V\u00e9ronique L.","family":"Billat","sequence":"additional","affiliation":[{"name":"Laboratoire Informatique, Bio-Informatique et Syst\u00e8mes Complexes (IBISC), Universit\u00e9 Paris-Saclay, 91034 Evry, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,27]]},"reference":[{"key":"ref_1","unstructured":"(2026, February 03). IAAF Race Walking Committee Makes Key Recommendations for Future of the Discipline|PRESS-RELEASE|World Athletics. Available online: https:\/\/worldathletics.org\/news\/press-release\/race-walking-committee-recommendations."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Norberg, J., and Schmitz, A. (2017). Is Race Walking Lower Impact Than Running?, American Society of Mechanical Engineers Digital Collection.","DOI":"10.1115\/IMECE2016-65126"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Pavei, G., Cazzola, D., Torre, A.L., and Minetti, A.E. (2019). Race Walking Ground Reaction Forces at Increasing Speeds: A Comparison with Walking and Running. Symmetry, 11.","DOI":"10.3390\/sym11070873"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1080\/17461391.2014.984769","article-title":"Ground Reaction Forces of Olympic and World Championship Race Walkers","volume":"16","author":"Hanley","year":"2016","journal-title":"Eur. J. Sport Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1556\/APhysiol.98.2011.2.6","article-title":"The Validity of Incremental Exercise Testing in Discriminating of Physiological Profiles in Elite Runners","volume":"98","year":"2011","journal-title":"Acta Physiol. Hung."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1249\/00005768-199204000-00015","article-title":"Running Economy of Elite Male and Elite Female Runners","volume":"24","author":"Daniels","year":"1992","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1136\/bjsm.23.4.250","article-title":"Physiological Determinants of Race Walking Performance in Female Race Walkers","volume":"23","author":"Yoshida","year":"1989","journal-title":"Br. J. Sports Med."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2235","DOI":"10.1080\/02640414.2018.1449086","article-title":"Race Walking Gait and Its Influence on Race Walking Economy in World-Class Race Walkers","volume":"36","author":"Tam","year":"2018","journal-title":"J. Sports Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1410","DOI":"10.1080\/02640414.2021.1876313","article-title":"The Dose-Response Relationship between Interval-Training and VO2max in Well-Trained Endurance Runners: A Systematic Review","volume":"39","author":"Parmar","year":"2021","journal-title":"J. Sports Sci."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1159\/000350256","article-title":"Physiological and Performance Adaptations to High-Intensity Interval Training","volume":"Volume 76","author":"Gibala","year":"2013","journal-title":"Nestle Nutrition Institute Workshop Series"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1080\/17461390701456148","article-title":"Oxygen Uptake Kinetics as a Determinant of Sports Performance","volume":"7","author":"Burnley","year":"2007","journal-title":"Eur. J. Sport. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"899","DOI":"10.1152\/jappl.2000.89.3.899","article-title":"Oxygen Uptake Kinetics in Treadmill Running and Cycle Ergometry: A Comparison","volume":"89","author":"Carter","year":"2000","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"13","DOI":"10.2165\/00007256-200131010-00002","article-title":"Interval Training for Performance: A Scientific and Empirical Practice. Special Recommendations for Middle- and Long-Distance Running. Part I: Aerobic Interval Training","volume":"31","author":"Billat","year":"2001","journal-title":"Sports Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1642","DOI":"10.1152\/jappl.1996.81.4.1642","article-title":"Influence of Muscle Fiber Type and Pedal Frequency on Oxygen Uptake Kinetics of Heavy Exercise","volume":"81","author":"Barstow","year":"1996","journal-title":"J. Appl. Physiol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1113\/EP092326","article-title":"Oxygen Uptake Slow Component: Enigma of the \u2018Excess\u2019 Oxygen Used during Heavy and Severe Exercise","volume":"110","author":"Poole","year":"2025","journal-title":"Exp. Physiol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1113\/jphysiol.2010.197723","article-title":"Skeletal Muscle Fatigue Precedes the Slow Component of Oxygen Uptake Kinetics during Exercise in Humans","volume":"589","author":"Cannon","year":"2011","journal-title":"J. Physiol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"e13776","DOI":"10.1111\/apha.13776","article-title":"The Effects of Exercise Intensity and Duration on the Relationship between the Slow Component of V\u0307O2 and Peripheral Fatigue","volume":"234","author":"Keir","year":"2022","journal-title":"Acta Physiol."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"O\u2019Donoghue, P. (2009). Research Methods for Sports Performance Analysis, Routledge.","DOI":"10.4324\/9780203878309"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"129","DOI":"10.2478\/hukin-2014-0118","article-title":"Changes in Energy Cost and Total External Work of Muscles in Elite Race Walkers Walking at Different Speeds","volume":"44","author":"Klimek","year":"2014","journal-title":"J. Hum. Kinet."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2785","DOI":"10.1113\/JP273230","article-title":"Low Carbohydrate, High Fat Diet Impairs Exercise Economy and Negates the Performance Benefit from Intensified Training in Elite Race Walkers","volume":"595","author":"Burke","year":"2017","journal-title":"J. Physiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1007\/s004210050573","article-title":"Determination of the Velocity Associated with the Longest Time to Exhaustion at Maximal Oxygen Uptake","volume":"80","author":"Billat","year":"1999","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2099","DOI":"10.1152\/jappl.1991.71.6.2099","article-title":"Linear and Nonlinear Characteristics of Oxygen Uptake Kinetics during Heavy Exercise","volume":"71","author":"Barstow","year":"1991","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_23","first-page":"139","article-title":"The Kinetics of Exertional Oxygen Uptake: Assumptions and Inferences","volume":"51","author":"Whipp","year":"1998","journal-title":"Med. Dello Sport."},{"key":"ref_24","first-page":"1506","article-title":"Parameters of Ventilatory and Gas Exchange Dynamics during Exercise","volume":"52","author":"Whipp","year":"1982","journal-title":"J. Appl. Physiol. Respir. Environ. Exerc. Physiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1881","DOI":"10.1152\/jappl.1989.67.5.1881","article-title":"Relative Importance of Aerobic and Anaerobic Energy Release during Short-Lasting Exhausting Bicycle Exercise","volume":"67","author":"Tabata","year":"1989","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.1249\/MSS.0000000000003169","article-title":"Short Severe Energy Restriction with Refueling Reduces Body Mass without Altering Training-Associated Performance Improvement","volume":"55","author":"Burke","year":"2023","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1037\/0033-2909.112.1.155","article-title":"A power primer","volume":"112","author":"Cohen","year":"1992","journal-title":"Psychol. Bull."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1447","DOI":"10.1007\/s00424-020-02437-7","article-title":"Bioenergetics of the VO2 Slow Component between Exercise Intensity Domains","volume":"472","author":"Colosio","year":"2020","journal-title":"Pflugers Arch."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2046","DOI":"10.1249\/MSS.0b013e31821fcfc1","article-title":"Slow Component of VO2 Kinetics: Mechanistic Bases and Practical Applications","volume":"43","author":"Jones","year":"2011","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1080\/17461391.2013.878755","article-title":"The Biomechanics of Race Walking: Literature Overview and New Insights","volume":"14","author":"Pavei","year":"2014","journal-title":"Eur. J. Sport. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"933","DOI":"10.1002\/j.2040-4603.2012.tb00419.x","article-title":"Oxygen Uptake Kinetics","volume":"2","author":"Poole","year":"2012","journal-title":"Compr. Physiol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1002\/j.2040-4603.2011.tb00314.x","article-title":"Exercise: Kinetic Considerations for Gas Exchange","volume":"1","author":"Rossiter","year":"2011","journal-title":"Compr. Physiol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1097\/00005768-200301000-00009","article-title":"Does the Mechanical Work in Running Change during the VO2 Slow Component?","volume":"35","author":"Borrani","year":"2003","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"575","DOI":"10.1152\/japplphysiol.01129.2007","article-title":"Progressive Recruitment of Muscle Fibers Is Not Necessary for the Slow Component of VO2 Kinetics","volume":"105","author":"Zoladz","year":"2008","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1208","DOI":"10.1152\/japplphysiol.01093.2016","article-title":"Skeletal Muscle Bioenergetics during All-out Exercise: Mechanistic Insight into the Oxygen Uptake Slow Component and Neuromuscular Fatigue","volume":"122","author":"Broxterman","year":"2017","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"104023","DOI":"10.1016\/j.resp.2023.104023","article-title":"V\u0307O2 (Non-)Linear Increase in Ramp-Incremental Exercise vs. V\u0307O2 Slow Component in Constant-Power Exercise: Underlying Mechanisms","volume":"311","author":"Korzeniewski","year":"2023","journal-title":"Respir. Physiol. Neurobiol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1007\/s10974-007-9116-7","article-title":"Energy Turnover for Ca2+ Cycling in Skeletal Muscle","volume":"28","author":"Barclay","year":"2007","journal-title":"J. Muscle Res. Cell Motil."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1242\/jeb.01408","article-title":"Mechanics and Energetics of Swinging the Human Leg","volume":"208","author":"Doke","year":"2005","journal-title":"J. Exp. Biol."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Sousa, A., Borrani, F., Rodr\u00edguez, F.A., and Millet, G.P. (2017). Oxygen Uptake Kinetics Is Slower in Swimming Than Arm Cranking and Cycling during Heavy Intensity. Front. Physiol., 8.","DOI":"10.3389\/fphys.2017.00639"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"612","DOI":"10.1007\/s00421-002-0779-x","article-title":"Oxygen Uptake Kinetics during Severe Intensity Running and Cycling","volume":"89","author":"Hill","year":"2003","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1139\/apnm-2019-0037","article-title":"Wavelet and Principal Component Analysis of Electromyographic Activity and Slow Component of Oxygen Uptake during Heavy and Severe Cycling Exercise","volume":"45","author":"Qi","year":"2020","journal-title":"Appl. Physiol. Nutr. Metab."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1113\/EP090444","article-title":"Energy Metabolism and Muscle Activation Heterogeneity Explain VO2 Slow Component and Muscle Fatigue of Cycling at Different Intensities","volume":"108","author":"Nascimento","year":"2023","journal-title":"Exp. Physiol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"2212","DOI":"10.1152\/jappl.2001.90.6.2212","article-title":"Is the VO2 Slow Component Dependent on Progressive Recruitment of Fast-Twitch Fibers in Trained Runners?","volume":"90","author":"Borrani","year":"2001","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1113\/EP092116","article-title":"Muscle Fatigue, Pedalling Technique and the VO2 Slow Component during Cycling","volume":"110","author":"MacDougall","year":"2025","journal-title":"Exp. Physiol."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1250","DOI":"10.1123\/ijspp.2018-0851","article-title":"Muscle Activation Patterns Correlate with Race Walking Economy in Elite Race Walkers: A Waveform Analysis","volume":"14","author":"Hanley","year":"2019","journal-title":"Int. J. Sports Physiol. Perform."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1055\/s-2007-972829","article-title":"Effect of Three Hours Race Walk on Energy Cost, Cardiorespiratory Parameters and Stride Duration in Elite Race Walkers","volume":"17","author":"Brisswalter","year":"1996","journal-title":"Int. J. Sports Med."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"947","DOI":"10.1152\/jappl.2001.90.3.947","article-title":"Decrease of O2 Deficit Is a Potential Factor in Increased Time to Exhaustion after Specific Endurance Training","volume":"90","author":"Demarle","year":"2001","journal-title":"J. Appl. Physiol."}],"container-title":["Journal of Functional Morphology and Kinesiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2411-5142\/11\/2\/174\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T09:01:54Z","timestamp":1777366914000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2411-5142\/11\/2\/174"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,27]]},"references-count":47,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["jfmk11020174"],"URL":"https:\/\/doi.org\/10.3390\/jfmk11020174","relation":{},"ISSN":["2411-5142"],"issn-type":[{"value":"2411-5142","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,27]]}}}