Why an inexact science sometimes requires a human touch
One of the major perils in football analytics is the temptation for boosters to resort to “scientism” to make their case, the belief that all troubling questions in the sport have an absolute answer grounded in irrefutable (and sometimes not yet discovered) scientific evidence.
This is not an issue for most serious statisticians. Normally statistical models indicate a set of probable outcomes under a limited set of circumstances (eg better shot ratios tend to lead to more points in a league season), rather than anything resembling an a posteriori truth. What matters most with regard to scientific rigour is the soundness of the method itself, eg. whether the sample size is large enough to be generally applied, ensuring there isn’t false causality implied in a correlation between two or more variables etc. etc.
Much of the general public however does not view science this way. For them, sentences that begin “Science says…” have the ring of absolute truth, even though “science” here may refer a limited set of tentative conclusions based on limited research.
One shouldn’t blame them for this misconception, however. Often members of the media, on a deadline and without the time or tools to properly vet study results, will uncritically accept and distort the conclusions of the latest eye-catching paper. This happens so frequently that scientific studies are now regarded as infallible edicts, to the point where even the appearance of a scientifically informed opinion is enough to convince, regardless of the strength (or even existence) of the actual evidence.
This issue of scientism came up in football this week with England manager Roy Hodgson’s criticism of Liverpool FC’s fitness preparation, which came in light of Raheem Sterling’s request to be rested for England’s Sunday Euro qualification match against Estonia. Afterward, Hodgson made his case against LFC’s “two day recovery” policy:
“Raheem might say it is something that is becoming ingrained in him and that he felt the need to talk about being tired more than he would normally do. We have never had any problems with that [Liverpool’s policy] but I don’t think there is a lot of medical evidence to support the two-day recovery so, if you want to, you might want to research that. Certainly the Germans who everyone admires so much, they don’t do it, that is for certain.”
Perhaps after reading this you think Hodgson is a dinosaur under the employ of the Old Boys club that is the English FA, while Liverpool FC are a modern football club that employ a fitness regimen in line with the latest scientific medical research on rest and recovery in elite athletics. Alternatively, you may have sided with Hodgson in the belief that the footballers of yesteryear were surely made of sterner stuff than Sterling.
What both views have in common is neither cites any evidence to support their claims. When one attempts to take Hodgson’s advice and look up current research on rest and recovery, a few studies seem to tentatively back up the England manager, including a 2013 paper by University of Calabria professor Vincenzo Scoppa and a 2010 paper from Christopher Carling in the Journal of Sports Science, though the papers involve a very limited sample of players and teams. Even if a longer term, wider study emerges, its results may not necessarily apply to every player individually when it comes to physical endurance.
Both the above papers also focus on the physiological/performance realm, while others like Dr. Andrew Hill at the University of Leeds have looked at the issue from a psychological perspective, noting the risk of burnout is higher among younger athletes with an extrinsically imposed perfectionist ideal. Yet while Hill’s research makes a compelling case for preserving Sterling’s mental health, this clearly wasn’t the focus of Hodgson’s ire. Nor is it clear whether LFC’s “two day rest” regimen has a more positive impact on preventing player burnout than, say, playing fewer total minutes for an entire season.
In the end, there doesn’t appear to be an obvious right and wrong in this situation. On the one hand, Hodgson may indeed be correct in asserting that Sterling’s preference for two days rest is an ingrained club habit rather than a prerequisite for sporting success. On the other, if two days guaranteed rest allows Sterling to play at what he feels is his best, Hodgson may be obliged to respect the player’s wishes, as footballers, ultimately, are the ones who go out there and win. Every player is different–some may perform at their best when training every day, while others may need the psychological break. Hodgson might simply try listening to Sterling the player–the human being–rather than complaining about Liverpool’s grasp of the often murky science of athletic performance.
The point is that in an area as complex and individual as player fatigue, the available science doesn’t necessarily provide a set of ready made solutions to every problem. This applies to other areas of sports science and analytics as well. It’s up to decision makers to take the time and effort to collect and analyze the strength of existing scientific research in order to best serve their club or country’s interests, rather than invoking almighty science like a preacher quoting scripture.