# Can the average Indian become a world class footballer?

## Footballer in his prime

In the age of performance statistics, it is only natural to ask at what age footballers get their best performance

We live in the age of big data and the associated statistical analysis. The first sport to extensively analyze athlete data was baseball. Anyone who has ever sat in a baseball stadium knows that not much happens and if it does, then at a leisurely pace. That gives the TV commentators plenty of time to discuss all sorts of statistics from the players involved. In football, too, we have seen a significant increase in the use of statistical methods for about ten years. Some modern football clubs now train with the help of computers and the players wear sensors on their bodies.

Here I would like to cover a much simpler topic and that is: At what age do football players perform their best? You keep hearing that a player is "old" because he has turned thirty. At the end of the eighties, Uli Stein was the "Methuselah" of German football just because he was in his mid-30s. In the Premier League, most players over 30 rarely get a multi-year contract. What do the statistics say?

### Distribution of the age of the players

The simplest way to answer the question raised above is to look at the age distribution of active players. Fig. 1 summarizes the statistics for the leagues in Germany, England, Italy and Spain (attackers only). The histogram shows the percentage of players in each age group.

As you can see, there is a maximum at 26 and 27 years. Assuming that this histogram also reflects the effectiveness of soccer players on average, then it looks like the best age for soccer games is between 22 and 30 years old (with maximum achievement at an age of 26-27 years old).

Football clubs in England have also hired analysts. The experts from Tottenham have calculated a very interesting curve that shows how often players in the various age groups have shot at the goal per minute. Shots on goal can be viewed as a kind of fitness indicator.

Here the maximum is not so pronounced, but you can see a slow decrease. The curve is a bit more dramatic than just the histogram of the age groups: At 29, a footballer shoots 50% less than at 22! From the age of 32, experience counts more than raw strength. Unfortunately, there is no curve for shots on goal, as younger players will certainly shoot at goal more often, but may not score as often.

The decrease in performance with age is clear. We can also look at other sports disciplines to see what the data tell us. For example, at the Rio Olympics, the median age of all male athletes was 26.2 years. For women it was 25.2 years. In athletics, the median age of all athletes was 25.9 years. "Olympic Sports - How Does Peak Age Vary?", TSZ, August 2016 The oldest athletes were the dressage riders, but it is the horse that has to exert itself ( the oldest gold winner of the games was a rider, 61 years old).

Athletics can be compared to soccer, as soccer players have gotten much faster and more athletic over the past 20 years. It is not uncommon for midfielders to reach 12 or more kilometers per game, and not in 90 minutes, since the ball is only really in motion for an average of 55 minutes in a match. Also, the players do not run 12 km at the same pace. There are lots of sprints where you can get up to 35 km / h. Since the energy consumed increases with the square of the speed, the expenditure in a game is enormous. Of the competitive sports in a team, only handball burns more calories per hour than football.

### Models of aging

Sports physicians have dealt extensively with the statistics of aging and have developed abstract models for them. A very interesting one was presented by Berthelot and others. Fig. 3 shows the main idea.

Performance in a particular discipline, such as running a marathon, is determined by two tendencies. On the one hand, performance increases with age (curve A (t)) because we become stronger and more experienced. On the other hand, performance also falls with age (the negative curve B (t)) because our body parts are "used up". The sum of both curves is the expected performance, in this case m / s for a marathon run (curve P (t)). There is a maximum and a plateau around 30 years. The green points are the top performance and the associated age of many marathon runners. As you can see, the curve P (t) can be adapted very well to the empirical data.

A much more nuanced study was presented by Alle and Hopkins in 2015. Based on several studies of the aging process in athletes, they have made a fundamental distinction. On the one hand, there are sports in which the total effort is no more than 500 seconds (especially in athletics). There are other sports in which more than an hour is "worked", e.g. cross-country skiing and cycling, but also football or handball.

The results of both authors can best be reproduced in Fig. 4. The left curve in Fig. 4 shows the age for peak performance depending on the number of seconds the sport lasts. For short events (e.g. 100-meter run), the optimal age is around 26 years. In the range of 500 seconds, the optimal age drops to 22 years. Younger athletes hold up an explosive effort (like a sprint) longer than the older ones. In sports where stamina is the main concern (right curve in Fig. 4), older athletes are better than the very young. In ultra marathons or very long competitions, athletes over 30 surprisingly have more stamina.

Now football is actually both. Periods of doing nothing suddenly turn into fast sprints and then slower runs. More than 10 km are run, but punctuated with fast sprints. The optimum then has to be somewhere in the middle, between the 22-year-old young and the 30-year-old old hand.

### Exceptional player: Messi vs Cristiano Ronaldo

But there are exceptional masters in every sport who can play for many more years. In the Premier League, Ryan Giggs, from Manchester United, skews any statistic because he didn't hang up his football boots until he was 40 years old.

The exceptional players of the moment are mainly Lionel Messi from FC Barcelona and Cristiano Ronaldo from Real Madrid. Messi started his professional career at 17 and CR at 18. Fig. 5 shows the statistics of goals per game by Messi (blue) and Cristiano Ronaldo (orange). The figure shows performance by age. Since Ronaldo is 33 and Messi is 30 years old, one would have to move the Messi curve in Fig. 5 three years to the right if one wanted to compare the players in the same season.

You can see that Messi matured much earlier and had his first performance peak at 24/25 years. Ronaldo peaked at the age of 27, but has remained at roughly the same level since then, despite being 33 years old. Messi had a second peak performance at the age of 28. Since then he has been playing a little further back in the field, as a half-midfielder or half-attacker. In that position he is much more crucial for Barcelona than Cristiano Ronaldo is for Real Madrid. However, their respective performances are far removed from any other player in the world.

### Who will win the next world championship?

Which brings us to the question of all questions. Who will win the next World Cup in Russia? The table (Fig. 6), created with data from transfermarkt.de, supplements the FIFA ranking with the estimated market value of the teams and the average age of the squad.

Germany and France are the youngest teams, very close to the magical age between 26-27. The three most expensive teams are France, Spain and Germany, which enter the race as favorites. The French team was the first team to break the team value barrier of one billion euros, but mainly because the market value of many players rose at an inflationary rate in 2017.

 Ranking country Average age Team value FIFA points 1 Germany 26,6 € 949.00 million 1609 2 Brazil 28,2 € 746.50 million 1489 3 Portugal 28,1 € 484.70 million 1360 4 Argentina 28,3 € 639.25 million 1359 5 Belgium 27,7 € 702.75 million 1337 6 Poland 27,8 € 267.75 million 1228 6 Spain 27,8 € 992.00 million 1228 8 Switzerland 27,4 € 175.75 million 1197 9 France 25,6 € 1.07 billion 1185 Fig. 6: FIFA ranking, average age and market value of the top ten national football teams (data from transfermarkt.de and FIFA).

The magazine "The Economist" has calculated that one year more in average age for a team can cost up to four positions in the final result of the World Cup.1 However, "older" teams have already won the World Cup. A negative example would be France at the 2002 World Cup, whose team was 28.3 years old on average. As the defending champion, you didn't even survive the preliminary round.

The teams of Argentina, Brazil and Portugal are the oldest in the competition this year (among the top ten). But they have the greatest exceptional talent, i.e. Messi, Neymar and Cristiano Ronaldo in the squad, probably the three most expensive players in the world and can therefore count themselves among the favorites.

Finally, Fig. 7 shows the mean age of all winners of the World Cup since 1930.2 On average, a winning team is 27.4 years old (roughly as in the case of Spain in 2010). But there is room, both upwards and downwards, as the table makes clear. However, only Brazil has managed to become champions once with a team of thirty-year-olds.

 year winner Average age 1962 Brazil 30,7 2006 Italy 29,6 1934 Italy 29 1954 Germany 28,5 1994 Brazil 28,5 1998 France 28,3 1982 Italy 27,9 1990 Germany 27,8 2010 Spain 27,3 1974 Germany 27,1 1930 Uruguay 27 1970 Brazil 26,9 1966 England 26,7 1986 Argentina 26,7 2002 Brazil 26,6 2014 Germany 26,4 1958 Brazil 26,3 1938 Italy 26,2 1950 Uruguay 25,9 1978 Argentina 25,7 Fig. 7: List of World Cup winners, sorted by average age.