B. Abernethy, R. J. Burgess-limerick, C. Engstrom, A. Hanna, and R. J. Neal, Temporal coordination of human gait Motor Control and sensory-motor intergration: issues and direction, pp.171-198, 1995.

R. M. Alexander, Optimization and gaits in the locomotion of vertebrates, Physiol Rev, vol.69, pp.1199-1227, 1989.

B. Almasbakk, H. T. Whiting, and J. Helgerud, The efficient learner, Biological Cybernetics, vol.84, issue.2, pp.75-83, 2001.
DOI : 10.1007/s004229900075

P. O. Astrand and K. Rodahl, Précis de physiologie de l'exercise musculaire, 1980.

B. G. Bardy, Perception et r??gulation du mouvement humain : plaidoyer pour une biologie physique, Journal de la Soci??t?? de Biologie, vol.200, issue.2, pp.135-143, 2006.
DOI : 10.1051/jbio:2006016

J. L. Bartlett and R. Kram, Changing the demand on specific muscle groups affects the walk-run transition speed, Journal of Experimental Biology, vol.211, issue.8, p.1288, 2008.
DOI : 10.1242/jeb.011932

H. Beaupied, F. Multon, and P. Delamarche, Does training have consequences for the walk???run transition speed?, Human Movement Science, vol.22, issue.1, pp.1-12, 2003.
DOI : 10.1016/S0167-9457(02)00139-2

N. A. Bernstein, The co-ordination and regulation of movement, 1967.

A. Beuter and F. Lalonde, Analysis of a phase transition in human locomotion using singularity theory, Neuroscience Research Communications, vol.3, pp.127-132, 1989.

G. Borg, Borg's perceived exertion and pain scales, 1998.

G. Borg, P. Hassmen, and M. Lagerstrom, Perceived exertion related to heart rate and blood lactate during arm and leg exercise, European Journal of Applied Physiology and Occupational Physiology, vol.15, issue.6, pp.679-685, 1987.
DOI : 10.1007/BF00424810

G. A. Borg, Perceived Exertion as an indicator of somatic stress, Scandinavian Journal of Rehabilitation Medecine, vol.2, pp.92-98, 1970.

G. A. Borg, Perceived exertion, Medicine & Science in Sports & Exercise, vol.5, issue.2, pp.90-93, 1973.
DOI : 10.1249/00005768-197300520-00017

G. A. Borg, G. Ljunggren, and R. Ceci, The increase of perceived exertion, aches and pain in the legs, heart rate and blood lactate during exercise on a bicycle ergometer, European Journal of Applied Physiology and Occupational Physiology, vol.35, issue.No 1???2, pp.343-349, 1985.
DOI : 10.1007/BF02337176

D. M. Bramble and D. E. Lieberman, Endurance running and the evolution of Homo, Nature, vol.3, issue.7015, 2004.
DOI : 10.1086/300083

J. Brener and S. Mitchell, Changes in energy expenditure and work during response acquisition in rats., Journal of Experimental Psychology: Animal Behavior Processes, vol.15, issue.2, pp.166-175, 1989.
DOI : 10.1037/0097-7403.15.2.166

J. Brisswalter and C. Hausswirth, Energie et performance physique et sportive, 2003.

J. Brisswalter and P. Legros, Comparaison du coût énergétique dans une population de coureurs de moyennes et de longues distances, Science et Sports, vol.7, pp.43-50, 1992.

J. Brisswalter and D. Mottet, Energy Cost and Stride Duration Variability at Preferred Transition Gait Speed Between Walking and Running, Canadian Journal of Applied Physiology, vol.21, issue.6, pp.471-480, 1996.
DOI : 10.1139/h96-041

M. P. Broderick and K. M. Newell, Coordination Patterns in Ball Bouncing as a Function of Skill, Journal of Motor Behavior, vol.18, issue.2, pp.165-188, 1999.
DOI : 10.1080/00222899909600986

N. Caillou, D. Delignieres, D. Nourrit, T. Deschamps, and B. Lauriot, Overcoming spontaneous patterns of coordination during the acquisition of a complex balancing task., Canadian Journal of Experimental Psychology/Revue canadienne de psychologie exp??rimentale, vol.56, issue.4, pp.283-293, 2002.
DOI : 10.1037/h0087404

M. A. Cairns, R. G. Burdett, J. C. Pisciotta, and S. R. Simon, A biomechanical analysis of racewalking gait, Medicine & Science in Sports & Exercise, vol.18, issue.4, pp.446-453, 1986.
DOI : 10.1249/00005768-198608000-00015

G. A. Cavagna, STORAGE AND UTILIZATION OF ELASTIC ENERGY IN SKELETAL MUSCLE, Exercise and Sport Sciences Reviews, vol.5, issue.1, pp.89-129, 1977.
DOI : 10.1249/00003677-197700050-00004

G. A. Cavagna and P. Franzetti, Mechanics of competition walking., The Journal of Physiology, vol.315, issue.1, pp.243-251, 1981.
DOI : 10.1113/jphysiol.1981.sp013745

P. R. Cavanagh and K. R. Williams, The effect of stride length variation on oxygen uptake during distance running, Medicine & Science in Sports & Exercise, vol.14, issue.1, pp.30-35, 1982.
DOI : 10.1249/00005768-198201000-00006

J. Y. Chow, K. Davids, C. Button, and M. Koh, Coordination changes in a discrete multi-articular action as a function of practice, Acta Psychologica, vol.127, issue.1, pp.163-176, 2008.
DOI : 10.1016/j.actpsy.2007.04.002

J. Cohen, Statistical Power Analysis for the Behavioral Sciences, 1988.

G. L. Daniels and K. M. Newell, Attentional focus influences the walk???run transition in human locomotion, Biological Psychology, vol.63, issue.2, pp.163-178, 2003.
DOI : 10.1016/S0301-0511(03)00024-3

D. Smet, K. Segers, V. Lenoir, and M. , Spatiotemporal characteristics of spontaneous overground walk-to-run transition, Gait & Posture, vol.29, issue.1, pp.54-58, 2009.
DOI : 10.1016/j.gaitpost.2008.06.005

J. C. Dean and A. D. Kuo, Energetic costs of producing muscle work and force in a cyclical human bouncing task, Journal of Applied Physiology, vol.110, issue.4, pp.873-880, 2011.
DOI : 10.1152/japplphysiol.00505.2010

D. Delignieres, L'approche dynamique du comportement moteur, Manuel de Psychologie du Sport, pp.65-80, 2004.

D. Delignieres, D. Nourrit, R. Sioud, P. Leroyer, M. Zattara et al., Preferred coordination modes in the first steps of the learning of a complex gymnastics skill, Human Movement Science, vol.17, issue.2, pp.221-241, 1998.
DOI : 10.1016/S0167-9457(97)00031-6

S. Demura and Y. Nagasawa, RELATIONS BETWEEN PERCEPTUAL AND PHYSIOLOGICAL RESPONSE DURING INCREMENTAL EXERCISE FOLLOWED BY AN EXTENDED BOUT OF SUBMAXIMAL EXERCISE ON A CYCLE ERGOMETER, Perceptual and Motor Skills, vol.15, issue.2, pp.653-663, 2003.
DOI : 10.1249/00005768-198205000-00015

P. E. Di-prampero, The Energy Cost of Human Locomotion on Land and in Water*, International Journal of Sports Medicine, vol.07, issue.02, 1986.
DOI : 10.1055/s-2008-1025736

F. J. Diedrich, W. H. Warren, and . Jr, Why change gaits? Dynamics of the walk-run transition., Journal of Experimental Psychology: Human Perception and Performance, vol.21, issue.1, pp.183-202, 1995.
DOI : 10.1037/0096-1523.21.1.183

F. J. Diedrich, W. H. Warren, and . Jr, The Dynamics of Gait Transitions: Effects of Grade and Load, Journal of Motor Behavior, vol.27, issue.1, pp.60-78, 1998.
DOI : 10.1016/0167-9457(94)90049-3

G. Durand, C. Goudal, J. Mercier, L. Gallais, D. Micallef et al., Energy correlate of gait change according to locomotion speed, Journal of Human Movement Studies, vol.26, pp.187-203, 1994.

M. Durand, V. Geoffroi, A. Varray, and C. Prefault, Study of the energy correlates in the learning of a complex self-paced cyclical skill, Human Movement Science, vol.13, issue.6, pp.785-799, 1994.
DOI : 10.1016/0167-9457(94)90018-3

C. J. Ebbeling, J. Hamill, and J. A. Crussemeyer, Lower Extremity Mechanics and Energy Cost of Walking in High-Heeled Shoes, Journal of Orthopaedic & Sports Physical Therapy, vol.19, issue.4, pp.190-196, 1994.
DOI : 10.2519/jospt.1994.19.4.190

R. G. Eston and J. G. Williams, Reliability of ratings of perceived effort regulation of exercise intensity., British Journal of Sports Medicine, vol.22, issue.4, pp.153-155, 1988.
DOI : 10.1136/bjsm.22.4.153

C. T. Farley and D. P. Ferris, 10 Biomechanics of Walking and Running, Exercise and Sport Sciences Reviews, vol.26, pp.253-285, 1998.
DOI : 10.1249/00003677-199800260-00012

C. T. Farley and C. R. Taylor, A mechanical trigger for the trot-gallop transition in horses, Science, vol.253, issue.5017, 1991.
DOI : 10.1126/science.1857965

J. Faulkner and R. Eston, Overall and peripheral ratings of perceived exertion during a graded exercise test to volitional exhaustion in individuals of high and low fitness, European Journal of Applied Physiology, vol.10, issue.5, pp.613-620, 2007.
DOI : 10.1007/s00421-007-0536-2

R. M. Fenton, Race walking groud reaction forces, 1984.

R. Flandrois, Le métabolisme aérobie à l'exercice musculaire, 1992.

B. Fougeron, J. Brisswalter, C. Goubault, and P. Legros, Le co??t ??nerg??tique de la marche athl??tique : ??volution en fonction de la vitesse de d??placement, Science & Sports, vol.13, issue.2, pp.87-89, 1998.
DOI : 10.1016/S0765-1597(97)86906-7

K. J. Ganley, A. Stock, R. M. Herman, M. Santello, and W. T. Willis, Fuel oxidation at the walk-to-run-transition in humans, Metabolism, vol.60, issue.5, pp.609-616, 2011.
DOI : 10.1016/j.metabol.2010.06.007

M. Garcin, J. F. Vautier, H. Vandewalle, M. Wolff, and H. Monod, Ratings of perceived exertion (RPE) during cycling exercises at constant power output, Ergonomics, vol.15, issue.10, pp.1500-1509, 1998.
DOI : 10.1055/s-2007-972831

N. Getchell and J. Whitall, Transitions To and From Asymmetrical Gait Patterns, Journal of Motor Behavior, vol.36, issue.1, pp.13-27, 2004.
DOI : 10.3200/JMBR.36.1.13-27

H. J. Green, J. Cadefau, R. Cusso, M. Ball-burnett, and G. Jamieson, Metabolic adaptations to short-term training are expressed early in submaximal exercise, Canadian Journal of Physiology and Pharmacology, vol.73, issue.4, pp.474-482, 1995.
DOI : 10.1139/y95-060

J. S. Greiwe and W. M. Kohrt, Energy expenditure during walking and jogging, J Sports, 2000.

S. Grillner, J. Halbertsma, J. Nilsson, and A. Thorstensson, The adaptation to speed in human locomotion, Brain Research, vol.165, issue.1, pp.177-182, 1979.
DOI : 10.1016/0006-8993(79)90059-3

J. M. Hagberg and E. F. Coyle, Physiologic Comparison of Competitive Racewalking and Running, International Journal of Sports Medicine, vol.05, issue.02, pp.74-77, 1984.
DOI : 10.1055/s-2008-1025883

H. Haken, Introduction to Synergetics, 1977.

H. Haken, Advanced Synergetics, 1983.
DOI : 10.1007/978-3-642-45553-7

H. Haken, Principles of Brain Functioning, 1996.
DOI : 10.1007/978-3-642-79570-1

H. Haken, J. A. Kelso, and H. Bunz, A theoretical model of phase transitions in human hand movements, Biological Cybernetics, vol.37, issue.5, pp.347-356, 1985.
DOI : 10.1007/BF00336922

J. Hamill, T. R. Derrick, and K. G. Holt, Shock attenuation and stride frequency during running, Human Movement Science, vol.14, issue.1, pp.45-60, 1995.
DOI : 10.1016/0167-9457(95)00004-C

D. B. Hampson, G. A. St-clair, M. I. Lambert, and T. D. Noakes, The Influence of Sensory Cues on the Perception of Exertion During Exercise and Central Regulation of Exercise Performance, Sports Medicine, vol.14, issue.5, pp.935-952, 2001.
DOI : 10.2165/00007256-200131130-00004

A. Hanna, B. Abernethy, R. J. Neal, and R. J. Burgess-limerick, Triggers for the transition between human walking and running, Energetics of Human Activity, pp.124-164, 2000.

R. K. Hetzler, R. L. Seip, S. H. Boutcher, E. Pierce, D. Snead et al., Effect of exercise modality on ratings of perceived exertion at various lactate concentrations, Medicine & Science in Sports & Exercise, vol.23, issue.1, pp.88-92, 1991.
DOI : 10.1249/00005768-199101000-00014

A. M. Heugas and T. Deschamps, Dynamics of competitive race walkers gaits: hypothesis of concomitant energetic cost Ref Type: Personal Communication Higgins Human Movement: An Integrated Approach, World Congress of Sport Medecine J. R, 1977.

K. J. Holt, S. F. Jeng, R. R. Rr, and J. Hamill, Energetic Cost and Stability during Human Walking at the Preferred Stride Frequency, Journal of Motor Behavior, vol.61, issue.2, pp.164-178, 1995.
DOI : 10.1007/BF00430237

S. L. Hong and K. M. Newell, Change in the Organization of Degrees of Freedom With Learning, Journal of Motor Behavior, vol.38, issue.2, pp.88-100, 2006.
DOI : 10.3200/JMBR.38.2.88-100

D. F. Hoyt and C. R. Taylor, Gait and the energetics of locomotion in horses, Nature, vol.63, issue.5820, pp.239-240, 1981.
DOI : 10.1038/292239a0

A. Hreljac, Preferred and energetically optimal gait transition speeds in human locomotion, Medicine & Science in Sports & Exercise, vol.25, issue.10, pp.1158-1162, 1993.
DOI : 10.1249/00005768-199310000-00012

A. Hreljac, Determinants of the gait transition speed during human locomotion: Kinematic factors, Journal of Biomechanics, vol.28, issue.6, pp.669-677, 1995.
DOI : 10.1016/0021-9290(94)00120-S

A. Hreljac, Effects of physical characteristics on the gait transition speed during human locomotion, Human Movement Science, vol.14, issue.2, pp.205-216, 1995.
DOI : 10.1016/0167-9457(95)00017-M

A. Hreljac, A. Arata, R. Ferber, J. A. Mercer, and B. S. Row, An Electromyographical Analysis of the Role of Dorsiflexors on the Gait Transition during Human Locomotion, Journal of Applied Biomechanics, vol.17, issue.4, pp.287-296, 2001.
DOI : 10.1123/jab.17.4.287

A. Hreljac, R. Imamura, R. F. Escamilla, and W. B. Edwards, Effects of changing protocol, grade, and direction on the preferred gait transition speed during human locomotion, Gait & Posture, vol.25, issue.3, 2007.
DOI : 10.1016/j.gaitpost.2006.05.005

A. Hreljac, R. T. Imamura, R. F. Escamilla, W. B. Edwards, and T. Macleod, The Relationship between Joint Kinetic Factors and the Walk???Run Gait Transition Speed during Human Locomotion, Journal of Applied Biomechanics, vol.24, issue.2, pp.149-157, 2008.
DOI : 10.1123/jab.24.2.149

C. L. Hull, Principles of Behavior, The Journal of Nervous and Mental Disease, vol.101, issue.4, 1943.
DOI : 10.1097/00005053-194504000-00026

L. C. Hunter, E. C. Hendrix, and J. C. Dean, The cost of walking downhill: Is the preferred gait energetically optimal?, Journal of Biomechanics, vol.43, issue.10, 1910.
DOI : 10.1016/j.jbiomech.2010.03.030

B. H. Jones, M. M. Toner, W. L. Daniels, and J. J. Knapik, The energy cost and heart-rate response of trained and untrained subjects walking and running in shoes and boots, Ergonomics, vol.25, issue.8, pp.895-902, 1984.
DOI : 10.1080/00140138408963563

K. Jordan, J. H. Challis, J. P. Cusumano, and K. M. Newell, Stability and the time-dependent structure of gait variability in walking and running, Human Movement Science, vol.28, issue.1, pp.113-128, 2009.
DOI : 10.1016/j.humov.2008.09.001

M. Kaneko, Mechanics and energetics in running with special reference to efficiency, Journal of Biomechanics, vol.23, issue.1, pp.57-63, 1990.
DOI : 10.1016/0021-9290(90)90041-Z

J. A. Kelso, Phase transitions and critical behavior in human bimanual coordination, Am.J Physiol, vol.246, pp.1000-1004, 1984.

J. A. Kelso and A. Fuchs, Self???organizing dynamics of the human brain: Critical instabilities and ??il???nikov chaos, Chaos: An Interdisciplinary Journal of Nonlinear Science, vol.5, issue.1, pp.64-69, 1995.
DOI : 10.1063/1.166087

J. A. Kelso, K. G. Holt, P. Rubin, and P. N. Kugler, Patterns of Human Interlimb Coordination Emerge from the Properties of Non-Linear, Limit Cycle Oscillatory Processes, Journal of Motor Behavior, vol.238, issue.4, pp.226-261, 1981.
DOI : 10.1080/00222895.1981.10735251

Y. G. Ko, J. H. Challis, and K. M. Newell, Learning to coordinate redundant degrees of freedom in a dynamic balance task, Human Movement Science, vol.22, issue.1, pp.47-66, 2003.
DOI : 10.1016/S0167-9457(02)00177-X

R. Kram, A. Domingo, and D. P. Ferris, Effect of reduced gravity on the preferred walkrun transition speed, J Exp.Biol, vol.200, pp.821-826, 1997.

P. N. Kugler, J. A. Kelso, and M. T. Turvey, 1 On the Concept of Coordinative Structures as Dissipative Structures: I. Theoretical Lines of Convergence, Tutorials in motor behavior, pp.3-47, 1980.
DOI : 10.1016/S0166-4115(08)61936-6

P. N. Kugler and M. T. Turvey, Information, natural laws, and the self-assembly of rhythmic movements, 1987.

B. S. Lay, W. A. Sparrow, K. M. Hughes, and N. J. Dwyer, Practice effects on coordination and control, metabolic energy expenditure, and muscle activation, Human Movement Science, vol.21, issue.5-6, pp.807-830, 2002.
DOI : 10.1016/S0167-9457(02)00166-5

L. Li, Stability Landscapes of Walking and Running Near Gait Transition Speed, Journal of Applied Biomechanics, vol.16, issue.4, pp.428-435, 2000.
DOI : 10.1123/jab.16.4.428

L. Li, J. M. Haddad, and J. Hamill, Stability and variability may respond differently to changes in walking speed, Human Movement Science, vol.24, issue.2, pp.257-267, 2005.
DOI : 10.1016/j.humov.2005.03.003

L. Li and J. Hamill, Characteristics of the Vertical Ground Reaction Force Component Prior to Gait Transition, Research Quarterly for Exercise and Sport, vol.30, issue.3, pp.229-237, 2002.
DOI : 10.1080/02701367.2002.10609016

P. Malcolm, P. Fiers, V. Segers, C. Van, I. Lenoir et al., Experimental study on the role of the ankle push off in the walk-to-run transition by means of a powered ankle-foot-exoskeleton, Gait & Posture, vol.30, issue.3, pp.322-327, 2009.
DOI : 10.1016/j.gaitpost.2009.06.002

P. Malcolm, V. Segers, I. Van-caekenberghe, and D. De-clercq, Experimental study of the influence of the m. tibialis anterior on the walk-to-run transition by means of a powered ankle-foot exoskeleton, Gait & Posture, vol.29, issue.1, pp.6-10, 2009.
DOI : 10.1016/j.gaitpost.2008.05.016

R. Margaria, Biomechanics and Energetics of Muscular Exercise, 1976.

R. Margaria, P. Cerretelli, P. Aghemo, and G. Sassi, Energy cost of running, J, 1963.

A. P. Marsh and P. E. Martin, Effect of cycling experience, aerobic power, and power output on preferred and most economical cycling cadences, Medicine &amp Science in Sports &amp Exercise, vol.29, issue.9, pp.1225-1232, 1997.
DOI : 10.1097/00005768-199709000-00016

P. V. Mcdonald, R. E. Van-emmerik, and K. M. Newell, The Effects of Practice on Limb Kinematics in a Throwing Task, Journal of Motor Behavior, vol.19, issue.3, pp.245-264, 1989.
DOI : 10.1080/00222895.1989.10735480

D. R. Menier and L. G. Pugh, The relation of oxygen intake and velocity of walking and running, in competition walkers, The Journal of Physiology, vol.197, issue.3, pp.717-721, 1968.
DOI : 10.1113/jphysiol.1968.sp008584

J. Mercier, G. D. Le, M. Durand, C. Goudal, J. P. Micallef et al., Energy expenditure and cardiorespiratory responses at the transition between walking and running. Eur, 1994.

K. J. Merritt, C. E. Raburn, and J. C. Dean, Adaptation of the preferred human bouncing pattern toward the metabolically optimal frequency, Journal of Neurophysiology, vol.107, issue.8, pp.2244-2249, 2012.
DOI : 10.1152/jn.00984.2011

A. E. Minetti, Invariant aspects of human locomotion in different gravitational environments, Acta Astronautica, vol.49, issue.3-10, pp.191-198, 2001.
DOI : 10.1016/S0094-5765(01)00098-4

A. E. Minetti, Biomechanics: Walking on other planets, Nature, vol.409, issue.6819, pp.467-469, 2001.
DOI : 10.1038/35054166

A. E. Minetti, L. P. Ardigo, and F. Saibene, The transition between walking and running in humans: metabolic and mechanical aspects at different gradients, Acta Physiologica Scandinavica, vol.131, issue.12, pp.315-323, 1994.
DOI : 10.1111/j.1748-1716.1994.tb09692.x

A. E. Minetti, C. Capelli, P. Zamparo, P. E. Di-prampero, and F. Saibene, Effects of stride frequency on mechanical power and energy expenditure of walking, Medicine & Science in Sports & Exercise, vol.27, issue.8, pp.1194-1202, 1995.
DOI : 10.1249/00005768-199508000-00014

W. D. Monteiro, P. T. Farinatti, C. G. De-oliveira, and C. G. Araujo, Variability of cardio-respiratory, electromyographic, and perceived exertion responses at the walk-run transition in a sample of young men controlled for anthropometric and fitness characteristics, European Journal of Applied Physiology, vol.18, issue.6, pp.1017-1026, 2011.
DOI : 10.1007/s00421-010-1720-3

P. Murray, G. N. Guten, L. A. Mollinger, and G. M. Gardner, Kinematic and electromyographic patterns of Olympic race walkers, The American Journal of Sports Medicine, vol.11, issue.2, pp.68-74, 1983.
DOI : 10.1177/036354658301100204

W. S. Myles and D. Maclean, A comparison of response and production protocols for assessing perceived exertion, European Journal of Applied Physiology and Occupational Physiology, vol.61, issue.6, pp.585-587, 1986.
DOI : 10.1007/BF00423201

R. R. Neptune and K. Sasaki, Ankle plantar flexor force production is an important determinant of the preferred walk-to-run transition speed, Journal of Experimental Biology, vol.208, issue.5, pp.799-808, 2005.
DOI : 10.1242/jeb.01435

K. M. Newell, Coordination, Control and Skill, Differing perspectives in motor learning, memory, and control, pp.295-317, 1985.
DOI : 10.1016/S0166-4115(08)62541-8

K. M. Newell, Constraints on the Development of Coordination, 1986.
DOI : 10.1007/978-94-009-4460-2_19

. Whiting, Motor development in children: aspects of coordination and control, pp.341-360

K. M. Newell, Motor Skill Acquisition, Annual Review of Psychology, vol.42, issue.1, pp.213-237, 1991.
DOI : 10.1146/annurev.ps.42.020191.001241

K. M. Newell and D. E. Vaillancourt, Dimensional change in motor learning, Human Movement Science, vol.20, issue.4-5, pp.695-715, 2001.
DOI : 10.1016/S0167-9457(01)00073-2

K. M. Newell and R. E. Van-emmerik, The acquisition of coordination: Preliminary analysis of learning to write, Human Movement Science, vol.8, issue.1, pp.17-32, 1989.
DOI : 10.1016/0167-9457(89)90021-3

K. M. Newell and R. E. Van-emmerik, Are Gesell's developmental principles general principles for the acquisition of coordination, Advances in Motor Development Research, pp.143-164, 1990.

B. M. Nigg, C. Emery, and L. A. Hiemstra, Unstable Shoe Construction and Reduction of Pain in Osteoarthritis Patients, Medicine & Science in Sports & Exercise, vol.38, issue.10, pp.1701-1708, 2006.
DOI : 10.1249/01.mss.0000228364.93703.53

A. D. Nimbarte and L. Li, Effect of Added Weights on the Characteristics of Vertical Ground Reaction Force During Walk-to-Run Gait Transition, Human Movement, vol.12, issue.1, pp.81-87, 2011.
DOI : 10.2478/v10038-010-0028-9

B. J. Noble and R. J. Robertson, Perceived exertion, 1996.

D. Nourrit, D. Delignieres, N. Caillou, T. Deschamps, and B. Lauriot, On Discontinuities in Motor Learning: A Longitudinal Study of Complex Skill Acquisition on a Ski-Simulator, Journal of Motor Behavior, vol.15, issue.2, pp.151-170, 2003.
DOI : 10.1080/02701367.1997.10608018

O. Dwyer, N. J. Neilson, and P. D. , Metabolic energy expenditure and accuracy in movement, 2000.

B. Odegard, N. Bulat, B. Savilonis, and Y. Mendelson, An analysis of race walking styles using a 2-dimensional mathematical knee model, Proceedings of the IEEE 23rd Northeast Bioengineering Conference, 1997.
DOI : 10.1109/NEBC.1997.594963

B. M. Owen and D. N. Lee, Establishing a Frame of Reference for Action, 1986.
DOI : 10.1007/978-94-009-4460-2_16

K. B. Pandolf, E. Kamon, and B. J. Noble, Perceived exertion and physiological responses during negative and positive work in climbing a laddermill, J Sports Med Phys.Fitness, vol.18, pp.227-236, 1978.

A. E. Patla and W. A. Sparrow, Factors that have shaped human locomotor structure and behavior: the 'Joules' in the crown, Energetics of human activity, pp.43-65, 2000.

S. J. Phillips and J. L. Jensen, Kinematics of racewalking, 1984.

T. Pozzo, A. Berthoz, and L. Lefort, Head kinematic during various motor tasks in humans, 1989.

E. Preatoni, Innovative methods for the analysis of sports movements and for the longitudinal monitoring of individual motor skills, 2007.

E. Preatoni, L. Torre, A. Rodano, and R. , A biomechanical comparison between racewalking and normal walking stance phase, Proceedings of the ISBS Symposium, 2006.

B. I. Prilutsky and R. J. Gregor, Swing-and support-related muscle actions differentially trigger human walk-run and run-walk transitions, J Exp.Biol, vol.204, pp.2277-2287, 2001.

H. J. Ralston, Energy-speed relation and optimal speed during level walking, Internationale Zeitschrift f??r Angewandte Physiologie Einschliesslich Arbeitsphysiologie, vol.109, issue.4, 1958.
DOI : 10.1007/BF00698754

R. J. Ratcliffe and K. G. Holt, Low frequency shock absorption in human walking, Gait & Posture, vol.5, issue.2, pp.93-100, 1997.
DOI : 10.1016/S0966-6362(96)01077-6

A. J. Raynor, C. J. Yi, B. Abernethy, and Q. J. Jong, Are transitions in human gait determined by mechanical, kinetic or energetic factors?, Human Movement Science, vol.21, issue.5-6, pp.785-805, 2002.
DOI : 10.1016/S0167-9457(02)00180-X

R. J. Robertson, Central signals of perceived exertion during dynamic exercise, Medicine & Science in Sports & Exercise, vol.14, issue.5, 1982.
DOI : 10.1249/00005768-198205000-00014

A. Rotstein, O. Inbar, T. Berginsky, and Y. Meckel, Preferred Transition Speed between Walking and Running: Effects of Training Status, Medicine & Science in Sports & Exercise, vol.37, issue.11, pp.1864-1870, 2005.
DOI : 10.1249/01.mss.0000177217.12977.2f

G. Schoner, A dynamic theory of coordination of discrete movement, Biological Cybernetics, vol.17, issue.4, pp.257-270, 1990.
DOI : 10.1007/BF00203449

G. Schoner and J. A. Kelso, Dynamic pattern generation in behavioral and neural systems, Science, vol.239, issue.4847, 1988.
DOI : 10.1126/science.3281253

G. Schoner, P. G. Zanone, and J. A. Kelso, Learning as Change of Coordination Dynamics: Theory and Experiment, Journal of Motor Behavior, vol.123, issue.1, pp.29-48, 1992.
DOI : 10.1007/BF00337040

P. K. Schot and M. J. Decker, The force driven harmonic oscillator model accurately predicts the preferred stride frequency for backward walking, Human Movement Science, vol.17, issue.1, pp.67-76, 1998.
DOI : 10.1016/S0167-9457(97)00019-5

V. Segers, P. Aerts, M. Lenoir, and D. De-clercq, Spatiotemporal characteristics of the walk-to-run and run-to-walk transition when gradually changing speed, Gait & Posture, vol.24, issue.2, pp.247-254, 2006.
DOI : 10.1016/j.gaitpost.2005.09.006

V. Segers, P. Aerts, M. Lenoir, and D. De-clercq, External Forces during Actual Acceleration across Transition Speed, Journal of Applied Biomechanics, vol.24, issue.4, pp.340-350, 2008.
DOI : 10.1123/jab.24.4.340

V. Segers, M. Lenoir, P. Aerts, and D. De-clercq, Influence of M. tibialis anterior fatigue on the walk-to-run and run-to-walk transition in non-steady state locomotion, Gait & Posture, vol.25, issue.4, pp.639-647, 2007.
DOI : 10.1016/j.gaitpost.2006.07.008

V. Segers, M. Lenoir, P. Aerts, and D. De-clercq, Kinematics of the transition between walking and running when gradually changing speed, Gait & Posture, vol.26, issue.3, pp.349-361, 2007.
DOI : 10.1016/j.gaitpost.2006.10.013

L. Seifert, L. Boulesteix, D. Chollet, and J. P. Vilas-boas, Differences in spatial-temporal parameters and arm???leg coordination in butterfly stroke as a function of race pace, skill and gender, Human Movement Science, vol.27, issue.1, pp.96-111, 2008.
DOI : 10.1016/j.humov.2007.08.001

D. Sentija, M. Rakovac, and V. Babic, Anthropometric characteristics and gait transition speed in human locomotion, Human Movement Science, vol.31, issue.3, pp.672-682, 2012.
DOI : 10.1016/j.humov.2011.06.006

K. Shung, C. G. De-oliveira, and J. Nadal, Influence of Shock Waves and Muscle Activity at Initial Contact on Walk???Run Transition Evaluated by Two Models, Journal of Applied Biomechanics, vol.25, issue.2, pp.175-183, 2009.
DOI : 10.1123/jab.25.2.175

W. A. Sparrow, The Efficiency of Skilled Performance, Journal of Motor Behavior, vol.33, issue.3, pp.237-261, 1983.
DOI : 10.1080/00222895.1983.10735299

W. A. Sparrow, Epilogue, Energetics of human activity, pp.286-296, 2000.

W. A. Sparrow, K. M. Hughes, A. P. Russel, and P. F. Le-rossignol, Movement economy, preferred modes, and pacing, Energetics of human activity, pp.96-123, 2000.

W. A. Sparrow, K. M. Hughes, A. P. Russell, and P. F. Le-rossignol, Effects of practice and preferred rate on perceived exertion, metabolic variables and movement control, Human Movement Science, vol.18, issue.2-3, pp.137-153, 1999.
DOI : 10.1016/S0167-9457(99)00005-6

W. A. Sparrow and K. M. Newell, Energy expenditure and motor performance relationships in humans learning a motor task, Psychophysiology, vol.27, issue.4, pp.338-346, 1994.
DOI : 10.1037//0096-1523.10.5.683

W. A. Sparrow and K. M. Newell, The coordination and control of human creeping with increases in speed, Behavioural Brain Research, vol.63, issue.2, pp.151-158, 1994.
DOI : 10.1016/0166-4328(94)90086-8

W. A. Sparrow and K. M. Newell, Metabolic energy expenditure and the regulation of movement economy, Psychonomic Bulletin & Review, vol.15, issue.Suppl. 1, pp.173-196, 1998.
DOI : 10.3758/BF03212943

B. Steenbergen, R. G. Marteniuk, and L. E. Kalbfleisch, Achieving Coordination in Prehension: Joint Freezing and Postural Contributions, Journal of Motor Behavior, vol.18, issue.4, pp.333-348, 1995.
DOI : 10.1080/00222895.1991.10118362

J. J. Temprado, M. Della-grasta, M. Farrell, and M. Laurent, A novice-expert comparison of (intra-limb) coordination subserving the volleyball serve, Human Movement Science, vol.16, issue.5, pp.653-676, 1997.
DOI : 10.1016/S0167-9457(97)00014-6

C. Teulier and D. Delignieres, The nature of the transition between novice and skilled coordination during learning to swing, Human Movement Science, vol.26, issue.3, pp.376-392, 2007.
DOI : 10.1016/j.humov.2007.01.013

C. Teulier, D. Nourrit, and D. Delignieres, The Evolution of Oscillatory Behavior During Learning on a Ski Simulator, Research Quarterly for Exercise and Sport, vol.18, issue.4, pp.464-475, 2006.
DOI : 10.1080/02701367.2006.10599381

C. Teulier and D. Nourrit-lucas, L'??volution des coordinations lors de l'apprentissage d'habilet??s motrices complexes, Science & Motricit??, vol.64, issue.64, pp.35-47, 2008.
DOI : 10.3917/sm.064.0035

A. Thorstensson and H. Roberthson, Adaptations to changing speed in human locomotion: speed of transition between walking and running, Acta Physiologica Scandinavica, vol.123, issue.2, pp.211-214, 1987.
DOI : 10.1111/j.1748-1716.1987.tb08228.x

E. C. Tolman, Purposive behavior in animals and men, 1932.

M. T. Turvey, K. G. Holt, M. E. Lafiandra, and S. T. Fonseca, Can the Transitions To and From Running and the Metabolic Cost of Running Be Determined From the Kinetic Energy of Running?, Journal of Motor Behavior, vol.34, issue.3, pp.265-278, 1999.
DOI : 10.1139/y82-035

M. T. Turvey, R. E. Shaw, and W. Mace, Issues in the theory of action: degrees of freedom, coordinative structures and coalitions, Attention and Performance (VII), 1978.

B. R. Umberger and P. E. Martin, Mechanical power and efficiency of level walking with different stride rates, Journal of Experimental Biology, vol.210, issue.18, pp.3255-3265, 2007.
DOI : 10.1242/jeb.000950

I. Van-caekenberghe, V. Segers, D. Smet, K. Aerts, P. De-clercq et al., Influence of treadmill acceleration on actual walk-to-run transition, Gait & Posture, vol.31, issue.1, pp.52-56, 2010.
DOI : 10.1016/j.gaitpost.2009.08.244

C. L. Vaughan and M. J. Malley, Froude and the contribution of naval architecture to our understanding of bipedal locomotion, Gait & Posture, vol.21, issue.3, pp.350-362, 2005.
DOI : 10.1016/j.gaitpost.2004.01.011

B. Vereijken, R. E. Van-emmerik, and H. T. Whiting, A Dynamical Systems Approach to Skill Acquisition, The Quarterly Journal of Experimental Psychology Section A, vol.39, issue.2, pp.323-344, 1992.
DOI : 10.1016/0167-9457(88)90017-6

B. Vereijken, H. T. Whiting, K. M. Newell, and R. E. Van-emmerik, Free(z)ing Degrees of Freedom in Skill Acquisition, Journal of Motor Behavior, vol.19, issue.1, pp.133-142, 1992.
DOI : 10.1016/0167-9457(85)90017-X

A. Voloshin and J. Wosk, An in vivo study of low back pain and shock absorption in the human locomotor system, Journal of Biomechanics, vol.15, issue.1, pp.21-27, 1982.
DOI : 10.1016/0021-9290(82)90031-8

G. A. Westerfield, The use of biomechanics in the judging of race walking, 2007.

A. M. Williams, K. Davids, and J. G. Williams, Visual perception and action in sport, 1999.

G. Wulf and C. H. Shea, Principles derived from the study of simple skills do not generalize to complex skill learning, Psychonomic Bulletin & Review, vol.28, issue.A, pp.185-211, 2002.
DOI : 10.3758/BF03196276

P. G. Zanone and J. A. Kelso, Evolution of behavioral attractors with learning: Nonequilibrium phase transitions., Journal of Experimental Psychology: Human Perception and Performance, vol.18, issue.2, pp.403-421, 1992.
DOI : 10.1037/0096-1523.18.2.403

M. Y. Zarrugh, F. N. Todd, and H. J. Ralston, Optimization of energy expenditure during level walking, European Journal of Applied Physiology and Occupational Physiology, vol.86, issue.15, pp.293-306, 1974.
DOI : 10.1007/BF00430237

G. Ziv and A. Rotstein, Physiological Characteristics of the Preferred Transition Speed in Racewalkers, Medicine & Science in Sports & Exercise, vol.41, issue.4, pp.797-804, 2009.
DOI : 10.1249/MSS.0b013e31818ff715