Effects of dancing on physical activity levels of children and adolescents: a systematic review.

BACKGROUND: Dancing has been suggested to increase the levels of physical activity of the youth. However, it is not clear what are the physiological characteristics of the dance classes for young people, mainly regarding the levels of moderate to vigorous physical activity (MVPA) during classes. It is also unclear if regular engagement in dance practices can contribute with increases in the amounts of daily/weekly MVPA, recommended by health organizations. OBJECTIVES: To conduct a systematic review verifying the amount of time spent at MVPA (primary outcome), by children and adolescents in the following situations: i) During dance classes, and ii) Before and after dance interventions. Secondary outcomes included: markers of exercise intensity during class, such as oxygen consumption (VO2) and heart rate (HR); VO2peak and lipid profile before and after dance interventions. METHODS: Six data sources were accessed (MEDLINE, EMBASE, Cochrane Wiley, PEDRO and SCOPUS). Study selection included different designs (acute, cohort, randomized controlled trials and others). Participants were from 6 to 19 years old, regularly engaged in dance practices. Methodological quality was assessed using the Downs and Black checklist. Two independent reviewers extracted characteristics and results of each study. RESULTS: 3216 articles were retrieved, and 37 included. Studies indicated that dance classes do not achieve 50% of total class time at MVPA. However, there are peaks of HR and VO2 during dance classes, which reach moderate and vigorous intensities. MVPA/daily/weekly did not improve before and after dance interventions for most of the studies, also VO2peak did not. The few results on lipid profile showed improvements only in overweight and obese participants. LIMITATIONS: Lack of meta-analysis, because there were not enough articles to be analyzed on any given outcome of interest, neither under the same study design. CONCLUSIONS: Results of individual studies indicated that dance classes did not active 50% of the total time at MVPA levels. This may be related to the absence of improvements in daily/weekly MVPA before and after dance interventions. VO2 and HR attained peaks of moderateto vigorous intensity during dance classes, suggesting that the structure of the classes may be manipulated to maintain longer periods at MVPA levels. Lack of data on cardiorespiratory fitness and metabolic outcomes limit conclusions on these parameters. IMPLICATIONS OF KEYS FINDS: Considering there are peaks of HR and VO2 during dance classes, we suggest that the structure of a dance class can be manipulate in order to induce cardiorespiratory and metabolic adaptations. Thus, dancing is a potential strategy to contribute with a healthy life style since the earliest ages. Prospero registration: CRD42020144609.