Injury reduction results using thermography in professional soccer teams (Updated)

10/08/2022 By: Ismael Fernández Cuevas, Alejandro del Estal & Víctor Escamilla Home

The promotion of Infrared Thermography as a technology that helps to prevent injuries is not just a commercial message, it is also supported by scientific and professional results. In this publication we show you some of the most interesting results about the utility of Thermography to reduce the injury incidence in high performance soccer teams.

As you might know, Infrared Thermography is a fast, non-invasive and objetive technology that allows the measurement of the skin temperature by just taking an photo (thermal image). This technology is not new, but its application as non diagnostic tool in health and sport is relatively recent. In the last decades, different research groups and companies as ThermoHuman, have explored the efficiency of thermography for, among other applications: injury prevention, injury monitoring and diagnosis support. But, besides the theory and marketing messages, which evidence can we find about it?

LaLiga study

One of the first publications made about Infrared Thermography and its application as injury prevention tool is the PhD performed by Pedro Gómez Carmona (Gómez Carmona, 2012). His work was firstly published in Spanish in 2012, but we have to wait until 2020 to get it translated and published in an impact factor journal (Gómez-Carmona et al., 2020). This work was performed with a first division soccer team from LaLiga (Spain). The injury rate from two consecutive pre-seasons were compared: no intervention performed in the first one (CPP), but during the second one (IRTPP) a thermography protocol was used.

“Using such a methodology (infrared thermography) […] ensured that the injury incidence and the days missed due to injury in the season were both reduced. This technique, if carried out by a qualified technician, could possibly become a source of objective information to help make informed injury prevention decisions”
Gómez Carmona et al., 2020

Thermal images were taken on a daily basis, establishing intervention rules based on the thermal asymmetries. The results confirmed a reduction of 70% of muscle injuries (from 15 to 6 [t46 = 1.964, P <.05]), being specially significant those in the region of the thigh (see figure 1). In addition to that, they authors found a reduction up to 90% in the number of days of absence due to injuries, pointing out its importance not only in number of injuries reduction, but in their severity as well (Gómez-Carmona et al., 2020).

**Figure 1.** Injury location across the 2 preseasons. CPP corresponded to the first preseason when the conventional injury prevention program was applied, and IRTPP corresponded to the second preseason when the infrared thermography injury prevention program was applied. *Statistically significant difference between the 2 seasons with P < .05. (Figure designed from a Freepik illustration and adapted from Gómez Carmona and collaborators, 2020)

Liga NOS study

Temporally speaking, the next work was performed by physiologist Matheus Fontes (figure 2) during his stay in Club Sport Marítimo (Liga NOS, Portugal). He arrived to the Madeira team during the 2016/2017 season, after working in Brazilian teams as Cruzeiro or Botafogo. As he explained, they implemented a GPS system and a thermography assessment, reducing drastically the number of muscle injuries: “…from 35 muscle injuries the previous season, we had nine this season using GPS and infrared thermography…”

“…With the systematic and individualized monitoring, it was possible to establish values for several parameters. When an athlete had a load imbalance, the technical commission was alerted, the data crossed and, consequently, the training modified or [the player] removed to avoid the injury. This dialogue was fundamental for reducing the injury incidence…”
Matheus Fontes (Former Physiologist at Club Sport Marítimo)

The results haven’t been published in a scientific journal yet, but it definitely helped Club Marítimo to reach an Europa League position during this 2016/2017 (best performance in the previous 5 years). The results was reported by this article in Blog Toque di Letra website.

**Figure 2.** Thermography data collection performed by Matheus Fontes during his stay at Club Sport Marítimo (image taken from Matheus Fontes social network)

Brasileirão study

In third place, one of the most interesting works performed using Thermography in professional soccer players is the publication done by Ana Carolina Côrte and collaborators (Côrte et l., 2019). Côrte is the Medical Doctor from Sport Club Corinthians Paulista, one of the most relevant teams from Brasileirão, the Brazilian first football division.

Côrte and collaborators (2019) performed a longitudinal prospective study with 28 professional soccer players between 2015 and 2016. In both seasons (2015 and 2016), muscle injuries were documented and classified in grade of severity, by ultrasound. During the following season (2016), an infrared thermography protocol was applied twice a week (48 hours after game) and if a difference of temperature was detected higher than 0.4°C, a prevention protocol was initiated (see figure 3).

**Figure 3.** Reference thermal asymmetry values and prevention protocol used by Côrte and collaborators during season 2016 at Corinthians (extracted from Côrte el al., 2019).

In 2015, the total number of muscle injuries was 11. In 2016, the total number of muscle injuries was 4 (p=0.04). It represents an incidence/player of 78% in 2015 and 28% in 2016, corresponding to a decrease of 64% in 2016. Among the seven players who played in both seasons, muscle injuries were reduced from 8 (in 2015) to 3 (in 2016) -a decrease of 63% in the season we used thermographic monitoring (p=0.06)- (Côrte et al., 2019).

“…Understanding the commercial value of an athlete in game conditions, it is important to consider the cost of an athlete in medical department […] the cost of players absence as a result of muscle injuries was, in 2015, U$472,500,00, instead U$ 155,000,00, in 2016…”
Côrte et al., 2019

In addition to the injury reduction results, the work from Côrte and collaborators (2019) is especially interesting because it estimates the economic impact of the injury reduction on the club budget: 317.500 USD less from one season to the following one (more than 67% cost reduction) -see figure 4-. In other words, a professional soccer team just needs to invest less than 7% of this amount (around 25.000 USD) to take care of the health of their players, to improve the team performance and to save money (more than 300.000 USD in the Brazilian team case).

**Figure 4.** Representation of injury reduction and saving estimation results from Côrte et al. (2019) Designed by Ismael Fernández Cuevas

Liga Pro Portugal study

Gonçalo Trindade, Sports Scientist at Clube Desportivo Nacional, has been collecting data in his team during the seasons 2020/2021 (using a GPS tracker) and 2021/2022 (using a combination of technologies, including thermography) with the aim of discovering the relevance in his players’ musculoskeletal injury incidence.

As previous studies, Gonçalo replicate the research of Matheus Fontes (Dias, V. 2017), Ana Carolina Côrte (Côrte et al. 2019) and Pedro Gómez (Gómez-Carmona et al. 2020) that have shown the implementation of thermography during a pre-season or a season may result in an important reduction of muscle injuries, ranging from 63-74%.

During the 2020/2021 season, only one technology, a GPS tracker, was used on a daily basis. Meanwhile, during the 2021/2022 season, a combination of sports technologies was used to have a wider perspective of the training load the players had. The same GPS tracker and tracking platform were used for this new season. In addition to it, thermography, a wellness questionnaire and neuromuscular assessments were made with the next frequencies, also represented in Figure 1:

MD: Match Day
MD⁺¹: Day Off
MD⁺²: GPS tracker, wellness questionnaire and thermography
MD^-4: GPS tracker, wellness questionnaire, neuromuscular assessment (only the players who did not play or played less than 30’)
MD^-3: GPS tracker, wellness questionnaire, neuromuscular assessment (only the players who played more than 60’)
MD^-2: GPS tracker, wellness questionnaire
MD^-1: GPS tracker, wellness questionnaire and thermography

PROTOCOL FOR INJURY REDUCTION — **Figure 1.** Description of the assessment performed in the protocol followed by the players in an usual week during the 2021/2022 season (MD: match day)

The results shown that during the 2020-2021 season, only a GPS tracker was used to monitor muscle imbalances, but there was no injury prevention protocol. A total of 26 muscle injuries were registered, as follows: hamstring (16), adductors (6), rectus femoris (3), calves (1). These injuries implied a total of 505 days out for the players.

At the end of the season 2021-2022, the total number of muscle injuries was 9, being hamstring (4), adductors (3), rectus femoris (2), calves (0). The players were injured and not playing for 167 days during the season. Figure 2 shows a summary of this data:

INJURY REDUCTION USING THERMOGRAPHY — **Figure 2.** Summary of the registered injuries and total days off during the seasons 2020-2021 and 2021/2022.

When both seasons are compared, a difference of -17 muscle injuries was found, which means a 65% reduction in muscle injuries. Counting the days out, there was a difference of -338 days, which means a 67% reduction in days out for the whole team. Comparing the 15 players who participated in both seasons, it was found that in the 2020-2021 season 13 muscle injuries (263 days out) were registered whereas only 4 (68 days out) were found in the 2021-2022 season, which reflects a decrease of 69% in muscle injuries and 74% in days out.

“By creating an injury reduction protocol, in which different technologies are combined, the players’ performance is optimized, more players are available to train and play, post-game recovery can be individualized according to the thermal response and injury recovery times and medical department costs are drastically reduced.”
Gonçalo Trindade (Sport Scientist at Clube Desportivo Nacional 2022)

Conclusions

All authors agree on the utility of infrared thermography as an injury prevention method in soccer teams. The key factor is based on a frequent and systematic use, and obviously, on a protocol and fluent information flow between the staff members to intervene from both preventive and load perspective. The similar results showed in this post confirmed the potential of infrared thermography to reduce injury incidence in high performance sports.

REFERENCES

Côrte, A. C., Pedrinelli, A., Marttos, A., Souza, I. F. G., Grava, J., & José Hernandez, A. (2019). Infrared thermography study as a complementary method of screening and prevention of muscle injuries: pilot study. BMJ Open Sport & Exercise Medicine, 5(1), e000431. doi: 10.1136/bmjsem-2018-000431

Dias, V. (2017). DNA mineiro: projeto inovador impulsiona retorno de time de Portugal à Liga Europa. Retrieved 05/03/2021, from https://toqdiletra.blogspot.com/2017/05/dna-mineiro-projeto-inovador-impulsiona-retorno-de-time-de-portugal-a-liga-europa.html

Gómez Carmona, P. M., Sillero Quintana, M., Fernández Cuevas, I., Noya Salces, J., & Fernández Rodríguez, I. (2009). Aplicación de un protocolo de prevención de lesiones basado en termografía infrarroja sobre futbolistas profesionales durante la pretemporada. Facultad de Ciencias de la Actividad Física y del Deporte – INEF. Universidad Politécnica de Madrid. Madrid.

Gómez-Carmona, P. M., Fernández-Cuevas, I., Sillero-Quintana, M., Arnáiz-Lastras, J., & Navandar, A. (2020). Infrared Thermography Protocol on Reducing the Incidence of Soccer Injuries. Journal of Sport Rehabilitation. doi: 10.1123/jsr.2019-0056