title: Effects of Pedal Speed and Crank Length on Pedaling Mechanics during Submaximal Cycling.
abstract: During submaximal cycling, the neuromuscular system has the freedom to select different intermuscular coordination strategies. From both a basic science and an applied perspective, it is important to understand how the central nervous system adjusts pedaling mechanics in response to changes in pedaling conditions.
  
  
  OBJECTIVE
  To determine the effect of changes in pedal speed (a marker of muscle shortening velocity) and crank length (a marker of muscle length) on pedaling mechanics during submaximal cycling.
  
  
  METHODS
  Fifteen trained cyclists performed submaximal isokinetic cycling trials (90 rpm, 240 W) using pedal speeds of 1.41 to 1.61 m·s(-1) and crank lengths of 150 to 190 mm. Joint powers were calculated using inverse dynamics.
  
  
  RESULTS
  Increases in pedal speed and crank length caused large increases knee and hip angular excursions and velocities (P < 0.05), whereas ankle angular kinematics stayed relatively constant (P > 0.05). Joint moments and joint powers were less affected by changes in the independent variables, but some interesting effects and trends were observed. Most noteworthy, knee extension moments and powers tended to decrease, whereas hip extension power tended to increase with an increase in crank length.
  
  
  CONCLUSIONS
  The distribution of joint moments and powers is largely maintained across a range of pedaling conditions. The crank length induced differences in knee extension moments, and powers may represent a trade-off between the central nervous system's attempts to simultaneously minimize muscle metabolic and mechanical stresses. These results increase our understanding of the neural and mechanical mechanisms underlying multi-joint task performance, and they have practical relevance to coaches, athletes, and clinicians.
authors.affiliation: 1Division of Sport, Health, and Exercise Sciences, Brunel University, Uxbridge, UNITED KINGDOM; 2Department of Biomechanics, English Institute of Sport, Manchester, UNITED KINGDOM; 3Departent of Exercise and Sport Science, University of Utah, Salt Lake City, UT; 4Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI.
authors.forename: Paul Richard
authors.initials: PR
authors.lastname: Barratt
authors.forename: James C
authors.initials: JC
authors.lastname: Martin
authors.forename: Steve J
authors.initials: SJ
authors.lastname: Elmer
authors.forename: Thomas
authors.initials: T
authors.lastname: Korff
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000502:physiology; D056352:Athletes; D001642:Bicycling / Q000502:physiology*; D001696:Biomechanical Phenomena; D005080:Exercise Test; D005260:Female; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D008297:Male; D016059:Range of Motion, Articular; D013647:Task Performance and Analysis; D055815:Young Adult