by Adrian Bell, University of Reading; James Reade, University of Reading; Richard Steckel, Ohio State University; & John Wilson, University of South Australia
Have football players been getting bigger over the years? Do we know enough about it? Do we care? Does it matter? Can you help us?
Well, the answer to the first question is almost certainly yes, however you look at it.
From the Figure below, which is data collected from www.worldfootball.net, the clear differences between types of player are evident. In the figure, we plot the average height per year for all players in the database, by position. Black is goalkeeper, red is defender, green midfielder and blue attacker. The first immediate point is that before 1950, the data are patchy – that’s why there are a lot of spikes and gaps.
But note also that goalkeepers are around 185cm, defenders nearer 180cm, attackers 178cm and midfielders the shortest at about 176cm. These height gaps have been quite steady for around the last thirty years, but compared to the 1950s are much higher. In the 1950s goalkeepers were only about 178cm, defenders 176cm, and both midfielders and attackers 174cm.
What has happened since then? Well, rules restricting the movement of footballers have been relaxed, and the rewards for winning matches and tournaments have changed greatly too, not least with the advent of live sport broadcast on TV. How might these have affected the selection into the sport by people at a young age, given particular physical characteristics?
Do we know enough about this? No. Despite collecting information on the heights of over 300,000 players from around the world, the data available from the internet is really only fairly complete after around the 1950s – so within living memory. More than that, we only know about the heights of those who played football – this is an outcome without much information about how it happened. We do not know enough information about the physical characteristics of the population at large – so for instance we could find that even if footballers increased in height over time, this is only reflective of general height increase across society. However the sample we have so far collected it at least not a random sample, since people don’t become footballers at random.
We want to study this more. And to do so, we need more data. We need it, in particular, for the period before the 1950s – from the above plot things become very variable before the mid-1950s, and that isn’t because people were suddenly really tall then really short, it’s because our samples are really small for these years, hence easily influenced by outliers like really tall or really short players.
So can you help us? We’d love it if you could. Maybe you have some old memorabilia that contains player heights? For instance match programmes, annual digests, player cards or club histories. Perhaps you’ve been looking up old players on Wikipedia and noticed that player heights often feature there? Either way, if you are interested you can help us by inputting your observations on player heights here: https://forms.gle/QtvtrXiqXv5ppckS9. All contributions are really welcome!
What might we do with the data? Despite suggestions to the contrary, we’re not really all that interested in proposing to FIFA that the goalposts should change. This has been something that the governing bodies have toyed with over the years as a way of making the game more interesting by encouraging more goals. Like most football fans, we actually enjoy nil nil draws! Rather, we’d like to just understand the patterns a little more. What rule changes, for example, led to changes in patterns of heights? How do footballer heights relate to other national characteristics? Are there other patterns such as between player positions, or between squads and matchday teams?
But we’d also like to spark all sorts of future research; so we plan this collection of player and height information to be an open data resource for all to use.