The effects of a ketogenic diet on athletes
Nutrition plays an essential role for an athletes’ performance and health. One of the nutrients athletes pay more attention to, are carbohydrates.
The health crisis caused by COVID-19 has stopped the daily lives of millions of people. Football has been no stranger to this paralysis. The return of the competition almost three months later includes a change in the regulation that allows a maximum of 5 substitutions per game and a bigger number of players can be called. However, the most important novelty is that all the remaining games will be played without supporters inside the stadium. How can playing without an audience affect the result of a game?
It is widely demonstrated that playing at home generates an advantage for the local team. The advantage of playing at home is measured by the percentage of points earned by the teams over the total points won. In the five European leagues (English Premier League, German Bundesliga, French Ligue 1, Italian Serie A and Spanish La Liga) the advantage of playing at home reaches an average value of 60.89%, ranging from a maximum of 62.25% in the Italian Serie A and a 58.35% of the German Bundesliga.1,2 In La Liga the value is 61.66%. The factors that explain this positive effect are diverse, but the two most important ones refer to the referee’s bias and the stimulating effect of the public on the player’s behaviour.3 Some lab research has shown how fan noise can cause up to a 15% increase for a referee to take the wrong decision favouring the local team.4,5 When there’s no environmental noise, the referee’s bias also disappears. It has also been demonstrated how the extra time is longer than it should be when the team that plays at home is losing by one goal compared to when it is winning. We also know that supporters cheers increases testosterone and cortisol levels in footballers who play at home compared to its rivals. The same effect takes place when comparing an official match to a friendly one. As Beckenbauer recently suggested, having a stimulating or dissuasive audience can be decisive for the competition.
A recent review has analysed 191 games that have been played without an audience since World War II in European football. Most of the games are after 2002 and they have mainly taken place in the Italian and French leagues. There is only one game of La Liga. The results of this review are relevant:
So, it seems that playing without fans in the stadium can change the result of a match. There’s more interesting information to think about. The big teams tend to keep their performance more stable at home or outside. Although playing at home may be very different for each team, it seems that the advantage of playing at home favours teams from small geographical areas with a very strong ethnic identity more than teams from big cities.6 These teams may be the most affected by playing without their supporters.
In summary, it is very probable that the positive effect of playing at home is reduced and that it may affect the final result of the championship. Coaches should prepare footballers very well to face this new competition atmosphere which completely differs from the one they are used to. In any case, we still must be cautious with these findings as there are other important factors such as the previous training made by the teams, the rivals level, or a probable scenario with injuries that can influence the outcome of the league.
Carlos Lago Peñas
1 Pollard, R., & Gómez, M.A. (2014). Components of home advantage in 157 national soccer leagues worldwide. International Journal of Sport and Exercise Psychology, 12, 218-233.
2 Sánchez, P.A., García-Calvo, T., Leo, F., Pollard, R., & Gómez, M.A. (2009). An analysis of home advantage in the top two spanish professional football leagues. Perceptual and Motors Skills, 108, 789-797.
3 Gómez, M. A., Lago-Peñas, C., & Pollard, R. (2013). Situational variables. In T. McGarry, P. O’Donoghue, & J. Sampaio (Eds.), Handbook of sports performance analysis (pp. 259–269). London: Routledge.
4 Nevill, A. M., Balmer, N. J., & Williams, A. M. (2002). The influence of crowd noise and experience upon refereeing decisions in football. Psychology of Sport and Exercise, 3(4), 261-272.
5Unkelbach, C., & Memmert, D. (2010). Crowd noise as a cue in referee decisions contributes to the home advantage. Journal of Sport and Exercise Psychology, 32(4), 483-498.
6 Pollard, R., & Gómez, M. A. (2009). Home advantage in football in South-West Europe: Long-term trends, regional variation, and team differences. European Journal of Sport Science, 9(6), 341-352.
Mental abilities, although not yet fully appreciated, are already considered a relevant part of performance. But their importance could go beyond that: Do they also influence the injury risk, including recurrence, once the player returns to play?
Although several studies have tried to evaluate the characteristics of the risk of injury in handball players, they have been unable to reach sufficiently reliable conclusions. A new study of all the FC Barcelona handball categories has attempted to shed more light on the subject.
Although there are several studies on this topic, many of them have analyzed these demands by looking at just a few variables or using very broad timeframes. A new study completed by physical trainers from F.C. Barcelona has analyzed several of these details more closely.
An article published in The Orthopaedic Journal of Sports Medicine —in which members of the club’s medical services participated— now suggests to consider the detailed structure of the area affected, and treating the extracellular matrix as an essential player in the prognosis of the injury.
In this article, Tim Gabbett and his team provide a user-friendly guide for practitioners when describing the general purpose of load management to coaches.
For the first time, it has been demonstrated that it does not take months of training to significantly improve both muscle volume and strength; instead, two weeks of an appropriate exercise are enough.
Training using eccentric exercises is important to prevent possible damage. However, intensive training can also cause muscle damage, so it is critical to be vigilant in order to keep injury risk to an absolute minimum.
Cardiovascular endurance manifests as a moderator of the load result to which the athlete is exposed.
Through the use of computer vision we can identify some shortcomings in the body orientation of players in different game situations.