You are presented with a paragraph from a COVID-19 literature. Classify the topics of this piece of text by choosing from the following categories:

- Epidemic Forecasting: The content relates to predictions about the spread of COVID-19.
- Treatment: The paragraph discusses therapeutic methods or medication for COVID-19.
- Prevention: The content covers measures to prevent the spread of COVID-19.
- Mechanism: The paragraph explains the biological mechanisms of the virus.
- Case Report: The content is a report of a COVID-19 case.
- Transmission: The paragraph discusses how COVID-19 is transmitted.
- Diagnosis: The content is about diagnosing COVID-19 in individuals.

Your classification should be provided as an element within a JSON array. The array should be formatted with topics enclosed in double quotes and separated by commas, following the JSON format, for example: ["Topic1", "Topic2", ...]. Include all applicable topics within the array. Your output should be a valid JSON array, and no additional text should be included in your response.

Article:

OBJECTIVES: The physical activity level (PAL) has significantly decreased as a result of the social distancing and lockdown related to the COVID19 pandemic, but there is a lack of knowledge on the correlates of PAL during the pandemic. The aim of this research was to examine the influence of pre-pandemic sports participation and substance use and misuse (SUM) on PAL during the COVID19 pandemic. MATERIAL AND METHODS: The study included 661 high-school students from Bosnia and Herzegovina (aged 15-18 years, 292 females). The investigation included 2 testing waves: before the COVID19 pandemic (baseline, January 2020) and during the COVID19 lockdown (follow-up, April 2020). The variables included PAL as measured by the Physical Activity Questionnaire for Adolescents, sports factors, and SUM. RESULTS: Sports factors at baseline were positively correlated with PALs at both baseline and follow-up. Smoking tobacco negatively affected PALs at both baseline and follow-up. Alcohol consumption was positively correlated with PAL at baseline but had no effect on PAL at follow-up. CONCLUSIONS: This study confirmed the importance of sports participation in maintaining PAL during challenging situations, such as the COVID19 lockdown. The substance-specific influence of SUM on PAL before and during the lockdown points to evident social and cultural aspects of SUM behaviors in adolescents. Further studies evidencing the cumulative effects of PAL decline during the lockdown are warranted. Int J Occup Med Environ Health. 2021;34(2):151-63.
["Prevention"]