During the 2018 FIFA World Cup in Russia, SportTechie and N3XT Sports are surveying key soccer experts around the world to understand the current state of soccer technology and innovation. (More soccer technology viewpoints.)
Francisco Forner is a strength and conditioning coach and a physical trainer. He worked as a fitness coach at Valencia CF for eight seasons, training players across the organization from the academy to the first team. He is currently pursuing a Ph.D. in sports science at the Catholic University of Valencia, where he is focusing on the use of heart rate variability in professional soccer.
While Forner believes GPS trackers have been very important in individualizing training loads by measuring movement around the field, he thinks the most significant advancements have come in heart rate variability and sleep monitoring. “HRV and sleep give objective and reliable information on the internal state of the players while GPS gives us information about the external loads of players,” he explained. “Having data on the internal state and external loads is an advantage for coaching staff for getting the highest performance of players. Heart rate variability is a non-invasive marker of the state of the autonomic nervous system and is seen as one of the methods for monitoring the individual adaptation to training and recovery and therefore knowing the individual state of fatigue of the athlete.
“[And] Sleep might be one of the best recovery methods.”
Improvements in technology mean that coaches can measure HRV or sleep easily and cheaply. That means their use can be implemented without distracting or discomforting a team’s players.
“Players should be able to measure sleep and HRV at their homes,” Forner explained. Part of that means scientists and coaching staff need to first agree on a protocol for the best methodologies and technologies to use to record these numbers. But also, “we have to convince players and explain the advantages of doing the right daily measurements. Some players might refuse it because they can think that the staff are entering in their private life. Our job is to convince them about the importance of measuring that data. All the information has the unique goal of getting their maximum performance level.”
Forner tracks daily metrics on his players using HRV measurements and a wellness questionnaire. “I advise players to try to slow down and to increase recovery methods when I observe that HRV decreases during two weeks in a row, for example. This helps me make informed decisions regarding my work with them and ensures that they are as competitive as they need to be, exactly at the right moment.”
According to Forner, athletic performance can depend on a range of different factors. “For this reason, we have to be able to build a holistic profile of each player by putting together in the same chart different values of markers. I believe that we will be able to measure all or almost all factors that have influence in performance thanks to new technologies. The most important challenge is going to be choosing the most relevant information, and not getting lost in the ocean of data.”