  Inertial motion analysis is having a growing interest during the last decades
due to its advantages over classical optical systems. The technological
solution based on inertial measurement units allows the measurement of
movements in daily living environments, such as in everyday life, which is key
for a realistic assessment and understanding of movements. This is why research
in this field is still developing and different approaches are proposed. This
presents a systematic review of the different proposals for inertial motion
analysis found in the literature. The search strategy has been carried out on
eight different platforms, including journal articles and conference
proceedings, which are written in English and published until August 2022. The
results are analyzed in terms of the publishers, the sensors used, the
applications, the monitored units, the algorithms of use, the participants of
the studies, and the validation systems employed. In addition, we delve deeply
into the machine learning techniques proposed in recent years and in the
approaches to reduce the estimation error. In this way, we show an overview of
the research carried out in this field, going into more detail in recent years,
and providing some research directions for future work
