title: Time trial exertion traits of cycling's Grand Tours.
abstract: We examined 26 professional riders during time trial (TT) competitions of the Grand Tours of cycling (Tour de France and Vuelta Espana; 1997-2003) for the exertional characteristics of contending vs. non-contending (i.e., support) riders. We categorized HR time during TT into training impulse (TRIMP) defined from seasonal VO2max testing [Phase I (<ventilatory threshold (VT approximately 64% VO2max); Phase II (VT-respiratory compensation threshold, approximately 83% VO2max); Phase III >RCP]. Races were: Short TT (<15 km; 8.9+/-2.9 km); Individual TT (>15 km; 48.12+/-8.7 km); Uphill TT (20.0+/-8.7 km) and Team TT (44.1+/-20.9 km). We observed statistically significant event-by-contender interactions for all TT (all, P<0.0001) except the short TT. During uphill TT, contenders exerted fewer total TRIMP (P<0.01), more Zone 3 TRIMP (P<0.05), and fewer Zone 2 TRIMP (P<0.01) vs. non-contenders. For individual TT, contenders accumulated more Total and Zone 3 TRIMP vs. non-contenders (all, P<0.05). Interestingly, during the team TT, contenders accumulated more Zone 3, and fewer Zone 2 TRIMP (all, P<0.05), despite having the opportunity to draft behind other riders while in paceline race formation. During TT events, contending riders compete at a level of exertion corresponding to a higher metabolic demand during the uphill TT, individual TT and team TT.
authors.affiliation: Pennington Biomedical Research Center, Exercise Biology Laboratory, Baton Rouge, 70808, USA. Conrad.Earnest@pbrc.edu
authors.forename: C P
authors.initials: CP
authors.lastname: Earnest
authors.forename: C
authors.initials: C
authors.lastname: Foster
authors.forename: J
authors.initials: J
authors.lastname: Hoyos
authors.forename: C A
authors.initials: CA
authors.lastname: Muniesa
authors.forename: A
authors.initials: A
authors.lastname: Santalla
authors.forename: A
authors.initials: A
authors.lastname: Lucia
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D003163:Competitive Behavior; D004734:Energy Metabolism / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D010101:Oxygen Consumption / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult