Bicycle ergometry and speed skating performance. A comparison between maximal power output during cycling and skating was made, and correlates of skating performance with bicycle performance and skating technique were investigated. Twenty-five well-trained speed skaters performed two bicycle tests and a 500-m and 1500-m ice skating race. The power (P) during skating is calculated from ice and air friction losses: at 500 m P500 = 344 +/- 60 W and at 1500 m P1500 = 283 +/- 65 W. Stroke frequency and pre-extension knee angle as principle determining factors of P were determined. The two bicycle tests (of 30" and 2'30" duration, maximal performance) yield P30C = 875 +/- 86 W and P2.30C = 420 +/- 52 W with VO2max = 4.76 +/- 0.45 l/min. The highest correlate of P500 as well as of P1500 appeared to be P30C, respectively, r = 0.78 and r = 0.85. Correlation coefficients between the power during skating and P2.30C or VO2max have a value of about 0.6. If the stroke frequency and P30C are correlated with the power during skating, then high multiple correlation coefficients are obtained: at 500 m R = 0.85 and at 1500 m R = 0.90.

Ice friction during speed skating. During speed skating, the external power output delivered by the athlete is predominantly used to overcome the air and ice frictional forces. Special skates were developed and used to measure the ice frictional forces during actual speed skating. The mean coefficients of friction for the straights and curves were, respectively, 0.0046 and 0.0059. The minimum value of the coefficient of ice friction was measured at an ice surface temperature of about -7 degrees C. It was found that the coefficient of friction increases with increasing speed. In the literature, it is suggested that the relatively low friction in skating results from a thin film of liquid water on the ice surface. Theories about the presence of water between the rubbing surfaces are focused on the formation of water by pressure-melting, melting due to frictional heating and on the 'liquid-like' properties of the ice surface. From our measurements and calculations, it is concluded that the liquid-like surface properties of ice seem to be a reasonable explanation for the low friction during speed skating. Published in Journal of biomechanics (1992)

A power equation for the sprint in speed skating. An analysis of the start of the 500 m speed skating races during the 1988 Olympic Winter Games showed a remarkably high correlation between the acceleration of the skater in the first second of the sprint and the final time (r = -0.75). In this study a power equation is used to explain this high coefficient of correlation. The performance in speed skating is determined by the capability of external power production by the speed skater. This power is necessary to overcome the air and ice friction and to increase the kinetic energy of the skater. Numerical values of the power dissipated to air and ice friction, both dependent on speed, are obtained from ice friction and wind tunnel experiments. Using aerobic and anaerobic power production as measured during supra maximal bicycle tests of international-level speed skaters, a model of the kinetics of power production is obtained. Simulation of power production and power dissipation yields values of speed and acceleration and, finally, the performance time of the sprint during speed skating.

Physiological and biomechanical comparison of roller skating and speed skating on ice. Eight well trained marathon skaters performed all-out exercise tests during speed skating on ice and roller skating. To compare these skating activities in relation to the concept of training specificity, relevant physiological (VO2, VE, RER and heart rate) and biomechanical variables (derived from film and video analysis) were measured. There were no significant differences between oxygen uptake (50.5 +/- 8.0 and 53.3 +/- 6.7 ml.min-1.kg-1), ventilation (102.4 +/- 11.2 and 116.0 +/- 11.1 1.min-1) or heart rate (174 +/- 12.2 and 176 +/- 14.5 min-1) between speed and roller skating. In roller skating a higher RER (1.16 +/- 0.1 cf. 1.05 +/- 0.1) was found. Power, work per stroke and stroke frequency were equal. Due to a higher coefficient of friction the maximal roller skating speed was lower. The effectiveness of push-off and parameters concerning the skating techniques showed no differences. In roller skating a 7.5% higher angle of the upper leg in the gliding phase occurred. It is speculated that the blood flow through the extensor muscles might be higher in roller skating.

A geometrical model of speed skating the curves. The centripetal force in speed skating the curves has to be delivered by the push off force which also does the external work to maintain the speed. Based on the geometry of the speed skating oval and the sideward push off characteristics in speed skating, a mathematical model of the power output in skating the curves was deduced. The power required to follow the curve is dependent on the mean speed in the curve, the work per stroke and the radius of the speed skating oval. Measurements (by means of film and video analysis) during the 5000 m races at the European Championships for ladies (n = 16) yielded on the one hand power from the geometrical model and on the other hand power losses due to air- and ice- friction. The difference between power delivered and power lost is used by the skaters to increase their speed. The difference between predicted power and measured power used to increase the kinetic energy of c.g. was only 3% thereby providing strong support for the validity of the model. The analysis suggested that skaters who want to accelerate in the curves should increase their work per stroke.

Speed skating is an intriguing sport to study from different perspectives due to the peculiar way of motion and the multiple determinants for performance. This review aimed to identify what is known on (long-track) speed skating, and which individual characteristics determine speed skating performance. A total of 49 studies were included. Based on a multidimensional performance model, person-related performance characteristics were categorized in anthropometrical, technical, physiological, tactical, and psychological characteristics. Literature was found on anthropometry, technique, physiology, and tactics. However, psychological studies were clearly under-represented. In particular, the role of self-regulation might deserve more attention to further understand mechanisms relevant for optimal performance and for instance pacing. Another remarkable finding was that the technically/biomechanically favourable crouched skating technique (i.e. small knee and trunk angle) leads to a physiological disadvantage: a smaller knee angle may increase the deoxygenation of the working muscles. This is an important underlying aspect for the pacing tactics in speed skating. Elite speed skaters need to find the optimal balance between obtaining a fast start and preventing negative technical adaptations later on in the race by distributing their available energy over the race in an optimal way. More research is required to gain more insight into how this impacts on the processes of fatigue and coordination during speed skating races. This can lead to a better understanding on how elite speed skaters can maintain the optimal technical characteristics throughout the entire race, and how they can adapt their pacing to optimize all identified aspects that determine performance.