Factors behind leisure-time physical activity behavior based on Finnish twin studies: the role of genetic and environmental influences and the role of motives

Abstract

Different approaches are being taken to clarify the role of various factors in the development of physical activity behaviors. Genetic studies are a new area of physical activity research and also the motives for physical activity have been widely studied. The purpose of this paper is to review the findings emerging from the longitudinal genetic studies on leisure-time physical activity and to evaluate the associations between motivational factors and leisure-time physical activity. The focus is to review recent findings of longitudinal Finnish twin studies. The results of the latest longitudinal Finnish twin studies point to the existence of age-specific genetic and environmental influences on leisure-time physical activity. Variations in environmental factors seem to explain the observed deterioration in leisure-time physical activity levels. A decline in genetic influences is seen first from adolescence to young adulthood and again from the age of thirty to the mid-thirties. In the Finnish twin participants, mastery, physical fitness, and psychological state were the major motivation factors associated with consistent leisure-time physical activity behavior. The results also indicate that intrinsic motivation factors may be important for engagement in leisure-time physical activity.

Figure 1

Participants in the Finnish twin studies originally described by Aaltonen et al. [27, 28, 65, 66].

Figure 2

The summary of the final genetic models for leisure-time physical activity between both ages of 16.2 and 24.5 years and ages of 29.6 and 35.6 years in Finnish twin studies. It is important to note that the cohorts used in the models between ages of 16.2 and 24.5 years and between ages of 29.6 and 35.6 years are not identical. Genetic and environmental influences are shown as percentages; upper value is for men and lower value is for women. Confidence intervals (95% CI) are shown in the parentheses. Additive genetic, shared environmental, and specific environmental correlations between the baseline and follow-up results are shown as curved arrows. The more detailed summaries for models are presented in the publications of Aaltonen et al. [27, 28].

Figure 3

Differences in the subdimensions of the REMM measurement scale among twin pairs who have been discordant for leisure-time physical activity over 30 years (twins from the Finnish Twin Cohort) [65]. The dark grey columns of the histogram represent twins who have been physically active over 30 years and the light grey columns represent their inactive cotwins. The names of the subdimensions are shown below the columns and the answer options are shown on the left hand side of the histogram. The P values above the columns indicate that there is a statistical difference between the active and inactive cotwins. The P value is shown only if a significant difference between the groups was detected.

Figure 4

Differences in the subdimensions of the REMM measurement scale among consistently physically active and inactive twin individuals in their mid-thirties (twins from the FinnTwin16 study) [66]. The dark grey columns of the histogram represent twin individuals who have been physically active for at least the last ten years and the light grey columns represent twin individuals who have been inactive for the same period of time. The names of the subdimensions are shown below the columns and the answer options are shown on the left hand side of the histogram. The P values above columns indicate that there is a statistical difference between the active and inactive cotwins.