Exercise as it relates to Disease/Do adolescents understand the impact of PA on mental health?

The following article is a critique and analysis of the paper: Adolescents’ knowledge about the benefits of physical exercises to mental health. Campos CG, Muniz LA, Belo VS, Romano MCC, Lima MdCJC, Coletiva S. 2019;24:2951-8.

What is the background to this research?
The study looks at what an adolescent population understands about how mental health is impacted by physical exercise, the benefits of which have been well documented. And if there is a correlation between this understanding with socioeconomic status. Research has shown that adolescents with higher PA levels have lower incidence of anxiety and depression, with obese adolescents increasingly likely to become overweight adults.

By understanding when an increase in knowledge may reduce physical inactivity levels and associated negative health outcomes will improve adolescent quality of life. By having background research of an adolescent cohorts knowledge about physical activity, and mental health the researchers aim to influence relevant public health care policies in clinical and education environments.

Where is the research from?
This article was published in August 2019 in SciELO. The Science & Collective Health Publication of the Brazilian Association of Public Health.

Maira de Castro Lima authored this study following an extensive history of research publications in Brazilian health science. Co-authors included Márcia Christina Caetano Romano who has published multiple studies on adolescent health, Vinícius Silva Belo who has significant publishing history in veterinary studies, and finally Cezenário Gonçalves Campos and Luciene Aparecida Muniz both of whom have co-authored a minimal amount of research papers.

With data to 2017 indicating the adolescent obesity rate in Brazil nearly tripled over the last 30 years along with more than 50% of the Brazilian adult population being declared obese, and given the WHO data supports the tripling of the obesity rate globally. The implications from this research could provide pivotal evidence to implement policy changes globally.

No authors declared a conflict of interest or external funding sources. This experimental study had ethics approval of the university of the Federal University of São João del-Rei.

What kind of research was this?
This study was completed in a state high school in the City of Minas Gerais.

As a descriptive observational study designed to learn and analyse data from a population at one point in time, a quantitative approach to the data analysis was applied. The study had 302 participants aged between 14 and 19, of which 65.8% were female and 34.2% male.

Study participants measurements where recorded using a questionnaire designed by the researchers due to a lack of an existing suitable alternative. The questionnaire and study could be easily replicated across many varied cohorts.

What did the research involve?
The research included the use of a profile card to characterise the sample studied, a structured questionnaire on physical exercise and mental health of twenty closed questions that categorised knowledge of the function of the CNS, anxiety and depressions, neurogenesis, self-image, self-esteem and their relation to mental health. The 20 closed questions were scored with one point. Each point adding up to indicate an increased knowledge of the relationship between PA and mental health.

The IPAQ short version and socioeconomic questionnaire of the Brazilian association of research companies was also used.

Data was collected over 30 days from students present on any day of data collection at the school. Of the 302 students, 121 were first year, 116 second year and 65 third year students.

Due to the small cohort, lack of randomisation of participants and no control group there are limitations to the research data. Furthermore it has limited validity due to lack of peer review or calibration of questions used. Questions were reviewed by the teaching faculty of the study school, not by education experts nor a psychometrician.

By using the International Physical Activity Questionnaire that had been validated for Brazil was used, with studies showing the use of the IPAQ should be avoided due to inaccurate responses.

No reference was made to any research regarding the comprehension of the study populations socioeconomic status or accuracy of this data. Providing further questions regarding the validity of this specific data.

SPSS 19 was used for statistical data analysis.

Therefore, this study can be described as having a low to medium level of evidence indicating further research is needed.

What were the basic results?
With a mean questionnaire score of 14.2 (71%) and a standard deviation of 2.2 points highlighting that the individuals with an increased knowledge of the benefits of PA on mental health are more active. A statically significant p> 0.05 was found with the comparison of socioeconomic status, the level of physical activity practised and the correlation of the level of knowledge.

Both the Kruskal-Wallis and Dunn's test showed statistical significance of p=0.002 between the sedentary, very active, active and irregularly active categories.

Study participants IPAQ level of physical activity characterisation (Table 1)

Study participants socioeconomic classification (Table 2)

What conclusions can we take from this research?
More knowledge of physical activity and its benefits to mental health will positively influence adolescents’ habits. Although knowledge does not result in behaviour transformations. Students classified as obese had high levels of nutritional knowledge and awareness of unhealthy eating habits, reinforcing education did not increase healthy behaviour adoption.

Individuals with less knowledge were more likely classed as sedentary, reinforcing the need for health and education interventions.

Those from poorer socioeconomic backgrounds within this study had higher levels of physical activity from necessity due to the use of walking and cycling as a means of daily transport. Additionally, females may have higher levels from an increased requirement to complete daily household chores.

A conclusion can be drawn that any physical activity knowledge intervention must consider the social context and individuality of an adolescent to have an increased chance of success.

Practical advice?
Awareness about physical activity benefits to mental health is critical to increasing self-engagement regardless of socioeconomic background, with knowledge potentially being a proactive mechanism against sedentary behaviours. Education interventions alone do not work for adolescents; interventions need to have stimulating behaviours.

Many strategies have been researched, designed and applied over the years, all of which may be beneficial. Notwithstanding the shift in technology-based distractions and ease of access to low nutrient foods, it needs to be considered how relevant and engaging these strategies have been.

Education of both adolescents and their primary care giver are two approaches that need to be undertaken. By educating adolescents and providing stimulating behavioural interventions the incidence of mental health issues will decline. Without primary caregivers engagement and adolescents having the adequate support from one or more of these, an interventions chance of success is decreased.

These interventions must be created and delivered in an appropriate easily understood format by adolescents for measurable changes to be seen.

Larger longitudinal studies are needed to confirm the results of this study. Further research to understand the highest level of knowledge regarding the positive benefits of physical activity on mental health, finding of which could be used across global adolescent populations.

Further information/resources
World Health Organisation e-library for nutrition actions

World Health Organisation Global Strategy on Diet, Physical Activity and Health

Brazilian Association of Research Companies

Guidelines for healthy growth & development for Children & young people (5 to 17 years)