Ontologically, our research is conducted from the perspective of human
motor behavior as a complex system at the interface of biomechanics and
motor control, with dynamical systems theory providing a means for
understanding the complexity of human motor behavior beyond the purely
mechanical analysis of movement. As our focus is on functional rather
than structural aspects, we investigate the time dynamics of behavior,
the changes in system states, and the constraints that affect state
changes rather than comparisons of states before and after training,
before and after learning. This perspective has given us another vision
of the nature of expertise, performance optimization, and motor control
and learning, especially through our studies on how the interactions of
constraints affect a system (constraints-led approach, Davids et al.,
2008) by testing its stability (adaptation to disturbance) and analyzing
its variability (flexibility between stable states).