Temporal relationships in the movement behaviour of adolescents: Testing and methodological considerations of the ActivityStat hypothesis

ABSTRACT

The study aimed to investigate the ActivityStat hypothesis by examining the presence and the timeframe of the temporal relationships among physical activity (PA) levels and stationary time (ST) in adolescents. A secondary analysis was performed on data involving 356 adolescents in Dunedin, New Zealand. Participants wore a waist-worn accelerometer for several consecutive days to assess PA levels [i.e. light PA (LPA), and moderate-to-vigorous PA (MVPA)] and ST. Bayesian continuous-time structural equation modelling (CT-SEM) was used to examine the relationship between the behaviours over time and the timeframe during which these relationships occur. Increases in LPA, MVPA, and ST were positively associated with their later behaviours until 2.5, 1.7, and 2 days later, respectively. A cross-behavioural reciprocal and negative relationship between LPA and ST was demonstrated 0.4 days later. A positive relationship between ST and MVPA was observed until about 0.4 days later. This is the first study to investigate the ActivityStat hypothesis using Bayesian CT-SEM in adolescents, examining the multivariate relationships among different behaviours and the associated timeframes. To conclude, evidence of activity synergy was suggested for the within-behavioural relationships, while behavioural compensation was noted for ST. Thus, the findings provide some support for the ActivityStat hypothesis in adolescents.

KEYWORDS:

• Behavioral compensation
• physical activity
• sedentary behaviour
• accelerometry
• youth

Disclosure statement

Sandra Mandic is the founder and the director of the research consultancy AGILE Research Ltd. (www.agileresearch.nz) and Principal Advisor Transport Strategy at Wellington City Council (Wellington, New Zealand). The other authors have no conflict of interest to report.

Supplementary material

Supplemental data for this article can be accessed online https://doi.org/10.1080/02640414.2024.2372929.

Additional information

Funding

The BEATS Study was supported by the Health Research Council of New Zealand Emerging Researcher First Grant [14/565], National Heart Foundation of New Zealand [1602 and 1615], Lottery Health Research Grant (Applic 341129), University of Otago Research Grant [UORG 2014], and Dunedin City Council and internal grants from the School of Physical Education, Sport and Exercise Sciences, University of Otago.