There are few things more agreeable than Christmas, that brandy-buttered entanglement of tradition and excess, of holly and folly, of diluted worship and super-concentrate refills of league football. At least in the eyes of football supporters. For them the festive season and the game are a timeless fit, like grannies and advocaat, and you can see why. In 1913-14 a full First Division programme took place on Christmas Day, Boxing Day and 27 December: a century on, while Europe draws breath over the holiday period, English football hyperventilates.
This season the Premier League promises a 12-day box of delights, including Arsenal v Chelsea, Chelsea v Liverpool and Manchester United v Spurs. We will revel in it – then, come next June, grimace when the physical hangover kicks in and England's World Cup ambitions become dust. There will be pained calls for a winter break. There always are on such occasions, even though it is one of those subjects, like bringing back national service, where the English prefer talk to action.
Much less discussed but equally fascinating is this: what effect does this football binge have on players and the Premier League table? One interesting fact is that, in nine of the past 10 seasons, teams who finished between first and sixth in May had a higher average points tally over Christmas compared with the rest of the season. Meanwhile teams who ended up between seventh and 20th performed worse on average during Christmas in eight out of 10 seasons.
One has to be a little careful here: the whims of the fixture list and a smallish sample size should not be ignored. Even so a reasonable explanation is that clubs with larger squads can tinker during the busy period while those with smaller squads are forced to trudge wearily on. And so the gap between the big teams and the rest is extenuated.
This is backed up by research by the former Wales assistant manager Raymond Verheijen. Last year he analysed 27,000 matches – from seven top-flight European leagues, the Champions League and Europa League – and found teams playing after only two days' recovery against teams who had enjoyed at least a three-day gap were 42% less likely to win. He has called for a three-day gap between matches mandatory in all fixture scheduling, adding: "The differences in performance between teams after a three and a six-day gap are almost imperceptible."
Meanwhile Prozone's Omar Chaudhuri has investigated a related area – how much does physical performance drop when a player is faced with a number of games over a short period? He did this by comparing 163 outfield Premier League players who played 90 minutes after two days' rest last Christmas to the 106 players who had three days to recover. The differences were striking.
Those with two days rest needed an average of three seconds more recovery after high intensity activities of 5.5 metres per second or faster. They made an average of 56.9 sprints a game, compared with 62.6 for those who had three days' recovery. They also took longer to get up to full speed and sprinted nearly 10% less distance on average in the game.
Chaudhuri then concentrated on midfielders and strikers – who tend to run more than defenders – and looked at the differences between those who played two, three and four games over Christmas. Again the drop-off was stark. To pick one example, footballers who played in two matches sprinted 69.5 times on average. The figure for those who played three games was 63.7. Four games? 58.0.
As Chaudhuri points out: "Physical data can be noisy and affected by a wide range of factors – the scoreline, whether a team is playing home or away, position, level of possession and so on – but players who had more rest and played fewer games had a significantly higher physical output. And while the sample is not huge, most of these results are statistically significant."
Tiredness may also lead to a greater risk of injury. Dr Scott McLean, director of the Injury Biomechanics Laboratory at the University of Michigan, has found evidence that fatigue changes the way the body moves in a way that leaves athletes more susceptible to injuring ligaments.
Yet most fans come from the "ain't broke, don't fix it" school. They believe that, if someone is earning £100,000-a-week, then four matches in 12 days should be a breeze; that, if clubs are concerned about tiredness in December, they should chop foreign tours in May and July. Then there is that chestnut, so old it could have been roasted on an open fire in a Dickens novel: you cannot plan for bad weather in Britain, so a winter break in a placid December could be followed by frozen sod in January and a mammoth fixture backlog.
Meanwhile, when fans hear Fabio Capello say that England are "the least fresh of any competing national side" at World Cups and European Championships because of the lack of a winter break, they shrug their shoulders. Either they do not believe there is a link or they believe it is a price worth paying.
Here is a modest proposal. In the season before the 2018 World Cup play matches until Boxing Day and then give Premier League teams a rest until the third round of the FA Cup. It would be more of a breather than a winter break. It might not have any impact. But by comparing this player performance data with the years where it was business as usual we would be better informed about the benefits of a break to clubs and England. And fans would still get their Boxing Day bonanza.