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Thibault Lussiana, Cyrille Gindre, Kim Hébert-Losier, Yoshimasa Sagawa, Philippe Gimenez and Laurent Mourot

Purpose:

No unique or ideal running pattern is the most economical for all runners. Classifying the global running patterns of individuals into 2 categories (aerial and terrestrial) using the Volodalen method could permit a better understanding of the relationship between running economy (RE) and biomechanics. The main purpose was to compare the RE of aerial and terrestrial runners.

Methods:

Two coaches classified 58 runners into aerial (n = 29) or terrestrial (n = 29) running patterns on the basis of visual observations. RE, muscle activity, kinematics, and spatiotemporal parameters of both groups were measured during a 5-min run at 12 km/h on a treadmill. Maximal oxygen uptake (V̇O2max) and peak treadmill speed (PTS) were assessed during an incremental running test.

Results:

No differences were observed between aerial and terrestrial patterns for RE, V̇O2max, and PTS. However, at 12 km/h, aerial runners exhibited earlier gastrocnemius lateralis activation in preparation for contact, less dorsiflexion at ground contact, higher coactivation indexes, and greater leg stiffness during stance phase than terrestrial runners. Terrestrial runners had more pronounced semitendinosus activation at the start and end of the running cycle, shorter flight time, greater leg compression, and a more rear-foot strike.

Conclusions:

Different running patterns were associated with similar RE. Aerial runners appear to rely more on elastic energy utilization with a rapid eccentric-concentric coupling time, whereas terrestrial runners appear to propel the body more forward rather than upward to limit work against gravity. Excluding runners with a mixed running pattern from analyses did not affect study interpretation.

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Eric Kyle O’Neal, Samantha Louise Johnson, Brett Alan Davis, Veronika Pribyslavska and Mary Caitlin Stevenson-Wilcoxson

local institutional review boards, and written informed consent was obtained from all participants. All participants were recreational or collegiate runners who participated in habitual training to compete in organized distance running events. Fifty-nine unique men and women provided between one and six

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Martin Buchheit, Bachar Haydar, Karim Hader, Pierre Ufland and Said Ahmaidi

Purpose:

To examine physiological responses to submaximal feld running with changes of direction (COD), and to compare two approaches to assess running economy (RE) with COD, ie, during square-wave (SW) and incremental (INC) exercises.

Methods:

Ten male team-sport athletes performed, in straight-line or over 20 m shuttles, one maximal INC and four submaximal SW (45, 60, 75 and 90% of the velocity associated with maximal pulmonary O2 uptake [vVO2pmax]). Pulmonary (VO2p) and gastrocnemius (VO2m) O2 uptake were computed for all tests. For both running mode, RE was estimated as the O2 cost per kilogram of bodyweight, per meter of running during all SW and INC.

Results:

Compared with straight-line runs, shuttle runs were associated with higher VO2p (eg, 33 ± 6 vs 37 ± 5 mL O2·min–1·kg–1 at 60%, P < .01) and VO2m (eg, 1.1 ± 0.5 vs 1.3 ± 0.8 mL O2·min–1·100 g–1 at 60%, P = .18, Cohen’s d = 0.32). With COD, RE was impaired during SW (0.26 ± 0.02 vs 0.24 ± 0.03 mL O2·kg–1·m–1, P < .01) and INC (0.23 ± 0.04 vs 0.16 ± 0.03 mL O2·kg–1·m–1, P < .001). For both SW and INC tests, the changes in RE with COD were related to height (eg, r = .56 [90%CL, 0.01;0.85] for SW) and weekly training/competitive volume (eg, r = –0.58 [–0.86;–0.04] for SW). For both running modes, RE calculated from INC was better than that from SW (both P < .001).

Conclusion:

Although RE is impaired during feld running with COD, team-sport players of shorter stature and/or presenting greater training/competitive volumes may present a lower RE deterioration with COD. Present results do not support the use of INC to assess RE in the feld, irrespective of running mode.

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Jan Schroeder, Franziska Erthel and Karsten Hollander

, swimming, and running, but not after cycling. 2 – 6 It was hypothesized that sport-associated direct and indirect impacts might generate damage to central nervous tissue. However, it has to be considered that these biomarkers are not only associated with central nervous processes but could also be due to

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Arturo Casado and Andrew Renfree

several studies have investigated pacing strategies in middle-distance (800 and 1500 m) running events, assessed through distribution of speeds over race segments, 2 – 4 other work has examined the influence of tactical positioning at intermediate points on finishing position. 5 Tactical issues are

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Paola Rodriguez-Giustiniani, Ian Rollo, Oliver C. Witard and Stuart D. R. Galloway

intermittent exercise is evidenced by the previously reported better maintenance of high-intensity running capacity ( McGregor et al., 1999 ). Several studies have demonstrated that consuming carbohydrate beverages before and at regular intervals during sporting activities improves subsequent high

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Philip Hurst, Lieke Schipof-Godart, Florentina Hettinga, Bart Roelands and Chris Beedie

authors’ knowledge, no study has investigated the effects of a placebo treatment on pacing strategy. In this study, we used a balanced placebo design to examine the placebo effects of caffeine on pacing strategy and performance over 1000-m running time trials. By using a balanced placebo design, we

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Ian N. Bezodis, David G. Kerwin, Stephen-Mark Cooper and Aki I.T. Salo

contacts divided by the time between them. Inertia data were taken from de Leva 18 apart from the feet, 19 with 200 g added due to the mass of the running spike. 8 Step frequency was calculated by dividing the step velocity by the step length. Comparisons against known locations on the track surface and

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Francesco Campa, Hannes Gatterer, Henry Lukaski and Stefania Toselli

. Procedures The athletes performed 2 running test sessions separated by 1 week. During each session, athletes ran on a treadmill for 30 minutes at an intensity corresponding to a score of 15 (heavy work) on the Borg scale. 8 They were randomly assigned to have a cold shower or no shower during the first

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Ricardo J.S. Costa, Robert Walters, James L.J. Bilzon and Neil P. Walsh

The purpose of the study was to determine the effects of carbohydrate (CHO) intake, with and without protein (PRO), immediately after prolonged strenuous exercise on circulating bacterially stimulated neutrophil degranulation. Twelve male runners completed 3 feeding interventions, 1 week apart, in randomized order after 2 hr of running at 75% VO2max. The feeding interventions included a placebo solution, a CHO solution equal to 1.2 g CHO~/kg body mass (BM), and a CHO-PRO solution equal to 1.2 g CHO/kg BM and 0.4 g PRO/kg BM (CHO+PRO) immediately postexercise. All solutions were flavor and water-volume equivalent (12 ml/kg BM). Circulating leukocyte counts, bacterially stimulated neutrophil degranulation, plasma insulin, and cortisol were determined from blood samples collected preexercise, immediately postexercise, and every 30 min until 180 min postexercise. The immediate postexercise circulating leukocytosis, neutrophilia, and lymphocytosis (p < .01 vs. preexercise) and the delayed lymphopenia (90 min postexercise, p < .05 vs. preexercise) were similar on all trials. Bacterially stimulated neutrophil degranulation decreased during recovery in control (23% at 180 min, p < .01 vs. preexercise) but remained above preexercise levels with CHO and CHO+PRO. In conclusion, CHO ingestion, with or without PRO, immediately after prolonged strenuous exercise prevented the decrease in bacterially stimulated neutrophil degranulation during recovery.