Vaccination in athletes, affordable research tools for all and the opportunities arising from publicly available data

When the first vaccinations against SARS-CoV-2 infections were available in early 2021 (at that time still with the alpha variant being most prevalent) there was a run for getting the shots as quickly as possible because this implied at least some freedom from Covid-related restrictions - and for athletes the opportunity to restart regular competition. However, many countries installed prioritization schedules with young and healthy athletes rather at the end of the row. Only improved vaccine availability and the upcoming Olympic Games were responsible for some mitigation of these rules among athletes. Although vaccination efficacy was somewhat reduced when the delta variant of the virus occurred, the overall immunization situation of athletes did not change very much. Omicron altered the clinical efficacy and at the same time the discussions within the sporting community. Still the vaccine was highly effective to prevent severe courses of Covid-19 but its protection against acquisition of the disease was almost lost. Given that young athletes mostly experienced mild courses, their motivation to get booster shots became very limited mainly because their individual benefit decreased more strongly than for older and more vulnerable persons. This scenario sets the frame for the study from Krzywański et al³. who have investigated within a large athlete cohort from Poland if the individual time lost from training and competition was larger due to vaccination or due to acquired Covid-19. Their results are quite clear and in favour of the vaccination. It has, however, to be taken into account that their study period was before omicron (in fact, under high prevalence of the delta variant) which limits direct transfer to our present situation but still there is potential applicability for infections like influenza and future viruses...

In addition, we are very happy to publish a study from a consortium involving a number of differently developed countries addressing physical activity in young children. The first author of this study comes from Malawi (current first affiliation: Strathclyde, UK) and was part of a larger research group. It is one of our main goals to support research from underrepresented countries (like Malawi). However, this has to be done without lowering the quality of papers which is a task not easy to achieve for a journal like ours. Over this year, we have already taken some action but still we have not arrived where we want to be. With the occurrence of more and more "transformative agreements" (facilitating open access to papers) between publishers and governments or university consortia the situation has already become worse for developing countries in terms of visibility for their research. This is because they cannot always afford the amount of money to be paid for such contracts. It will be the responsibility of both parties within transformative agreements to either include developing countries (governments, consortia) or to offer them acceptable open-access conditions (publishers). Besides all these considerations, the paper from Mwase-Vuma et al⁴. reports data from a broad and multi-national study (13 countries) which utilized accelerometry and compared it to simpler (cheaper) ways of assessing physical activity in 3-4 year old children. However, parent assessment of physical activity in their children (the cheap approach) failed to match the objective measurement sufficiently. Instead, there was a tendency for the parents to overestimate the activity of their offspring. Nevertheless, it is of particular importance to examine and validate affordable tools and methods for research in large populations. Otherwise, such studies (and not only their publication) will soon be limited to a small number of countries where technical devices are more easily available for researchers.

The third paper to be highlighted in this issue illustrates a recent trend: the more extensive utilization of publicly available data (Charest et al.)¹. With the given media coverage of highly professional sports and the increasing ability of researchers to extract respective information from existing databanks, the opportunity arises to address some research questions more conveniently than before. The authors from Canada and the US have used this to investigate more than 17,000 National Hockey League matches and analyze them with regard to the influence of travelling and time zone changes on match outcome in a convincing manner. Results confirm the widely held belief that the outcome of away matches is negatively influenced by the travelling distance (regardless of the direction). A similar example had already been highlighted in issue 4, 2022: the Hoenig et al². study about injury epidemiology in soccer which - in contrast to the one in this issue - utilized individual data. This leads to more detailed analyses being possible within the data set but larger concerns around data quality from public sources.