Numerical optimization of pacing strategy in cross-country skiing

When studying events involving locomotive exercise, such as cross-country skiing, one generally assumes that pacing strategies (i.e. power distributions) have a significant impact on performance. In order to better understand the importance of pacing strategies, a program is developed for numerical simulation and optimization of the pacing strategy in cross-country ski racing. This program computes the optimal pacing strategy for an arbitrary athlete skiing on a delineated course. The locomotion of the skier is described by introducing the equations of motion for cross-country skiing. A transformation of the motion equations is carried out in order to improve the simulation. Furthermore, a nonlinear optimization routine is connected to the simulation program. Simulation and optimization are performed on a fictional male skier. Results show that it is possible to attain an optimal pacing strategy by simulating cross-country skiing while connecting nonlinear optimization routines to the simulation. It is also shown that an optimal pacing strategy is characterized by minor variations in speed. In our opinion, this kind of optimization could serve as essential preparations before important competitions.

[1]  Carl Foster,et al.  Biodynamics. Effect of pacing strategy on energy expenditure during a 1500-m cycling time trial. , 2007, Medicine and science in sports and exercise.

[2]  Per Tveit,et al.  Cross‐Country Skiing , 2004, Sports biomechanics.

[3]  Øyvind Sandbakk,et al.  Metabolic rate and gross efficiency at high work rates in world class and national level sprint skiers , 2010, European Journal of Applied Physiology.

[4]  K. Svanberg The method of moving asymptotes—a new method for structural optimization , 1987 .

[5]  D. Swain A model for optimizing cycling performance by varying power on hills and in wind. , 1997, Medicine and science in sports and exercise.

[6]  G Atkinson,et al.  Pacing strategies during a cycling time trial with simulated headwinds and tailwinds , 2000, Ergonomics.

[7]  T D Noakes,et al.  Metabolic and performance responses to constant-load vs. variable-intensity exercise in trained cyclists. , 1999, Journal of applied physiology.

[8]  Kjell Hausken,et al.  Cross-country skiing motion equations, locomotive forces and mass scaling laws , 2008 .

[9]  M. Schrager,et al.  Effect of pacing strategy on cycle time trial performance. , 1993, Medicine and science in sports and exercise.

[10]  D. Swain,et al.  Physiological effects of constant versus variable power during endurance cycling. , 1998, Medicine and science in sports and exercise.

[11]  Mats Ainegren,et al.  Skiing Economy and Efficiency in Recreational and Elite Cross-Country Skiers , 2013, Journal of strength and conditioning research.

[12]  G Atkinson,et al.  Acceptability of Power Variation during a Simulated Hilly Time Trial , 2006, International journal of sports medicine.

[13]  J J de Koning,et al.  Relative importance of pacing strategy and mean power output in 1500-m self-paced cycling , 2009, British Journal of Sports Medicine.

[14]  Matej Supej,et al.  Analysis of sprint cross-country skiing using a differential global navigation satellite system , 2010, European Journal of Applied Physiology.

[15]  Nancy N. Thompson,et al.  Pacing Strategy and Athletic Performance , 1994, Sports medicine.

[16]  Carl Foster,et al.  Pacing strategy and the occurrence of fatigue in 4000-m cycling time trials. , 2006, Medicine and science in sports and exercise.

[17]  P R Cavanagh,et al.  Power equations in endurance sports. , 1990, Journal of biomechanics.

[18]  Mats Ainegren,et al.  Numerical simulation of cross-country skiing , 2011, Computer methods in biomechanics and biomedical engineering.

[19]  D. Bishop,et al.  Effect of performance level on pacing strategy during a 10-km running race , 2010, European Journal of Applied Physiology.

[20]  L. Vivier,et al.  Pacing strategy and VO2 kinetics during a 1500-m race. , 2008, International journal of sports medicine.

[21]  J J De Koning,et al.  Optimal pacing strategy: from theoretical modelling to reality in 1500-m speed skating , 2009, British Journal of Sports Medicine.

[22]  Sauli Savolainen,et al.  Drag Area of a Cross-Country Skier , 1988 .

[23]  G. Atkinson,et al.  Variable versus constant power strategies during cycling time-trials: Prediction of time savings using an up-to-date mathematical model , 2007, Journal of sports sciences.

[24]  E. Coyle,et al.  Load and Velocity of Contraction Influence Gross and Delta Mechanical Efficiency , 1992, International journal of sports medicine.

[25]  Kevin Thomas,et al.  Reproducibility of pacing strategy during simulated 20-km cycling time trials in well-trained cyclists , 2011, European Journal of Applied Physiology.

[26]  J. Pringle,et al.  Assessment of Maximal Aerobic Power and Critical Power in a Single 90-s Isokinetic All-Out Cycling Test , 2006, International journal of sports medicine.

[27]  M F Bobbert,et al.  Determination of optimal pacing strategy in track cycling with an energy flow model. , 1999, Journal of science and medicine in sport.

[28]  Hansueli Rhyner,et al.  The kinetic friction of polyethylen on snow: the influence of the snow temperature and the load , 2001 .