  Today many compact and efficient on-water data acquisition units help the
modern coaching by measuring and analyzing various inertial signals during
kayaking. One of the most challenging problems is how these signals can be used
to estimate performance and to develop the technique. Recently we have
introduced indicators based on the fluctuations of the inertial signals as
promising additions to the existing parameters. In this work we report about
our more detailed analysis, compare new indicators and discuss the possible
advantages of the applied methods. Our primary aim is to draw the attention to
several exciting and inspiring open problems and to initiate further research
even in several related multidisciplinary fields. More detailed information can
be found on a dedicated web page, http://www.noise.inf.u-szeged.hu/kayak.
