Mechanical Energetics of World Class Cross-Country Skiing

The purpose of this study was to determine whether world class skiers were alike in their mechanical power outputs (normalized for body mass and velocity and called mechanical cost, MTC) and body segment energy transfers when skiing in competition on level and uphill terrain using the diagonal technique. Eleven competitors were analyzed from film taken during a 15-km World Championship race on a level (1.6°) and uphill (9.0°) section of the course. Metabolic rates were estimated from assumptions concerning the efficiencies of positive and negative work and calculations, from the film, of the mechanical power produced by the skiers. The results showed that skiing on the slope was 2.2 times more demanding mechanically than skiing on a level track (MTC of 4.0 vs. 1.8 J • kg−1 • m−1, respectively). Skiers who had high MTC had low energy transfers (r = −0.9). Even in this presumably homogeneous group of elite skiers there were large individual differences in MTC and other mechanical variables, suggesting techn...

[1]  R. Hughson,et al.  The energy cost of cross-country skiing among elite competitors. , 1979, Medicine and science in sports.

[2]  Herbert Elftman,et al.  FORCES AND ENERGY CHANGES IN THE LEG DURING WALKING , 1939 .

[3]  P A Costigan,et al.  Mechanical energy of walking of stroke patients. , 1986, Archives of physical medicine and rehabilitation.

[4]  D. Winter,et al.  Predictions of knee and ankle moments of force in walking from EMG and kinematic data. , 1985, Journal of biomechanics.

[5]  R W Norman,et al.  Mechanical energy analyses of the human during local carriage on a treadmill. , 1981, Ergonomics.

[6]  S Y Aleshinsky,et al.  An energy 'sources' and 'fractions' approach to the mechanical energy expenditure problem--I. Basic concepts, description of the model, analysis of a one-link system movement. , 1986, Journal of biomechanics.

[7]  W. O. Fenn WORK AGAINST GRAVITY AND WORK DUE TO VELOCITY CHANGES IN RUNNING , 1930 .

[8]  G. Cavagna,et al.  MECHANICAL WORK IN RUNNING. , 1964, Journal of applied physiology.

[9]  B. C. Abbott,et al.  The physiological cost of negative work , 1952, The Journal of physiology.

[10]  G. Cavagna,et al.  The sources of external work in level walking and running. , 1976, The Journal of physiology.

[11]  D. Winter A new definition of mechanical work done in human movement. , 1979, Journal of applied physiology: respiratory, environmental and exercise physiology.

[12]  Pietro Enrico di Prampero,et al.  Energetics of muscular exercise , 1981 .

[13]  D. Winter,et al.  Transfers of mechanical energy within the total body and mechanical efficiency during treadmill walking. , 1980, Ergonomics.

[14]  A. E. Chapman,et al.  Factors determining changes in lower limb energy during swing in treadmill running. , 1983, Journal of biomechanics.

[15]  P R Cavanagh,et al.  A model for the calculation of mechanical power during distance running. , 1983, Journal of biomechanics.

[16]  S. Aleshinsky An energy 'sources' and 'fractions' approach to the mechanical energy expenditure problem--V. The mechanical energy expenditure reduction during motion of the multi-link system. , 1986, Journal of biomechanics.

[17]  J C Pezzack,et al.  An assessment of derivative determining techniques used for motion analysis. , 1977, Journal of biomechanics.

[18]  D A Winter,et al.  Measurement and reduction of noise in kinematics of locomotion. , 1974, Journal of biomechanics.

[19]  S Y Aleshinsky,et al.  An energy 'sources' and 'fractions' approach to the mechanical energy expenditure problem--III. Mechanical energy expenditure reduction during one link motion. , 1986, Journal of biomechanics.

[20]  J. van den Berg,et al.  EMG to force processing III: Estimation of model parameters for the human triceps surae muscle and assessment of the accuracy by means of a torque plate. , 1981, Journal of biomechanics.

[21]  H. Elftman THE WORK DONE BY MUSCLES IN RUNNING , 1940 .

[22]  S. Aleshinsky An energy 'sources' and 'fractions' approach to the mechanical energy expenditure problem--II. Movement of the multi-link chain model. , 1986, Journal of biomechanics.

[23]  P V Komi,et al.  Mechanical Efficiency of Pure Positive and Pure Negative Work with Special Reference to the Work Intensity , 1986, International journal of sports medicine.

[24]  S Y Aleshinsky,et al.  An energy 'sources' and 'fractions' approach to the mechanical energy expenditure problem--IV. Criticism of the concept of 'energy transfers within and between links'. , 1986, Journal of biomechanics.

[25]  R. Norman,et al.  1986 Volvo Award in Biomechanics: Partitioning of the L4 - L5 Dynamic Moment into Disc, Ligamentous, and Muscular Components During Lifting , 1986, Spine.

[26]  Graham E. Caldwell,et al.  Differences in Body Segment Energy Utilization between World-Class and Recreational Cross-Country Skiers , 1985 .