This experiment aimed to show that these fans are united in just one thing, their passion for football. 

Under the motto ‘When we feel together, we feel stronger’ these 42 supporters - one of each club – took part in a pioneering sound experiment in Spain. 

They recorded the rhythm of fans’ heartbeats to the tempo of the new La Liga soundtrack, composed by Lucas Vidal.

“The passion for football is something that all fans share. Sometimes rivalry makes us lose sight of that,” Enrique Moreno, La Liga's global brand and assets director said in a statement. 

“At LaLiga we are convinced that football is a great link that connects and brings together everyone who loves the sport.”

La Liga kicked off a campaign a few months ago calling on fans who always sang throughout the game in support of their team. 

More than 4,000 people signed up for the initiative and finally, 42 supporters were selected, from eight different nationalities. 

All of them enthusiastically went to Madrid, without knowing what surprise La Liga had in store for them. 

When the fans arrived, they anonymously took part in the sound experiment, without knowing the origin or club of the supporter standing next to them.

This experiment was inspired by a scientific study carried out a few years ago by the University of Gothenburg (Sweden), which showed that if several people sang the same song simultaneously, their heart rates synchronize with each other, going up and down together, which is linked to their synchronized breathing when they sing the same song.

The protagonists of the experiment were a group of of 18-year-old individuals with mixed gender.

In this case, La Liga wanted to demonstrate this premise, by doing it with real fans in a single day, under the concept ‘When we feel together, we feel stronger.’ 

To do this, La Liga established a series of parameters that ensured that the measurements followed the characteristics of each individual, marking a specific frequency range in which we expected all fans to be at the end of the experiment. 

This all took place under the supervision of Dr Tania Rodríguez Gabella, a cardiologist at the Clínico University Hospital in Valladolid. Once this parameter was established, the frequency of each fan was measured using heart rate monitors, which sent the signal to a common screen in which Rodríguez Gabella and scientists monitored the evolution of the beats.

Hours after the start of the test, the initial objective was achieved, with figures of 95% or 100% of matched subjects were reached in some sections of the melody.

One of the key points of the experiment was the anonymity of all participants. From the beginning, contact among them was prevented, to carry out the initiative in the purest possible way, to avoid prejudices that could provoke historical sporting rivalries.

For this reason, all the fans arrived dressed in shirts and black trousers, without being able to see the team kits that the others were wearing underneath. At the end of the activity, when their hearts were beating in unison, the composer Lucas Vidal who acted as choir director, invited them to reveal their kits.

“It was amazing to see how they worked together, no matter where they came from or what club they represented. Everyone was under the spell of the La Liga soundtrack. They felt it and made it their own,” said Vidal.

The whole experiment was recorded by film director Álvaro Brechner who was commissioned to create a short film that portrays this exciting experiment.

“It has been a beautiful project, we have all been infected with the energy and enthusiasm of the fans and this is something that can be seen in the result obtained; a video that speaks about harmony and passion for football,” Brechner said.