Forces on hockey players and conservation laws: On the theoretical efficiency of different techniques

Abstract

With a more comprehensive, yet still idealized, take on the analysis by Nässén et al (2019 Eur. J. Phys. 40 065005) regarding the efficiency of different ice skating strides, we find no superiority of the 'angular momentum skating' technique within their model. The fundamental reason is that for the 'angular momentum stride', there is a force component opposing the forward motion during the latter part of the stride, but not so for the traditional skating technique. We conclude with a short pedagogical discussion regarding conservation laws in physics.