It is well known that physical fitness is closely related to cognitive functions, both in adults and children. Mediators of this relationship, however, are neither well researched nor well understood. Additionally, studies have traditionally focused on individual exercise rather than team sports, which are decidedly easier to implement in school settings.
A recent paper published in BMC Public Health has sought to contribute to the scientific literature in both regards. A group of 36 adolescents (16 female, 20 male) participated in trials of 60 minutes of soccer and 60 minutes of sitting, separated by one week. They were then tested for information processing, inhibitory control, and working memory. During analysis, they were subsequently divided into a high-fit and a low-fit group.
The researchers additionally tested participants’ blood for levels of brain-derived neurotrophic factor (BDNF), which is hypothesized to play a role in the relation between physical fitness, physical activity, and improved cognition.
The results of the study demonstrate, in line with prior research, that overall information processing response times were quicker in the high-fit group. Furthermore, response times did not differ for high-fit individuals between exercise and resting trials, whereas low-fit individuals performed significantly better following rest as compared to post-exercise.
Most interesting, however, is the fact that 60 minutes of soccer was found to be beneficial for working memory only in the high-fit group. Thus, physical fitness mediates the relationship between physical exercises and improvements in cognition reported by previous studies. The authors speculate that differences in relative intensity may be explanatory in this regard, as the low-fit group demonstrated significantly greater exertion during the activity.
This is despite the fact that BDNF levels in the blood were unaffected by exercise, meaning that, contrary to previously hypothesized pathways, BDNF may not play a role in the relation between physical fitness and improved cognition. However, the authors note the level of exertion may not have been sufficient to increase BDNF post-exercise, and also that only levels of BDNF in the blood were measured, and not in the brain.
The authors note some limitations, including the fact that socioeconomic status was not taken into account and its cross-sectional rather than longitudinal nature, which represent important opportunities for future researcher.
Understanding how physical fitness and improved cognition are related is key to providing the best possible environments for children to learn and grow. The present study, with its use of a team sport, is for this reason of particular value to schools. That physically fit individuals benefit most from the cognitive benefits of exercise fills an important gap in the literature regarding this relation and how best to exploit it.
The study, “Effect of football activity and physical fitness on information processing, inhibitory control and working memory in adolescents“, was authored by Ryan A. Williams, Simon B. Cooper, Karah J. Dring, Lorna Hatch, John G. Morris, Caroline Sunderland, and Mary E. Nevill.