Related Experiment Video
Updated: Jun 3, 2025
Quantified Assessment of Infant's Gross Motor Abilities Using a Multisensor Wearable
Published on: May 17, 2024
Device-measured physical activity in adults born preterm with very low birth weight and mediation by motor abilities
Silje Dahl Benum1, Kristina Anna Djupvik Aakvik1, Cathrin Vano Mehl1
1Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
Insights
Adults born with very low birth weight (VLBW) engage in less moderate-to-vigorous physical activity (MVPA). This reduction is partly explained by poorer gross motor abilities, suggesting interventions targeting motor skills may increase PA in this population.
Area of Science:
- Developmental Pediatrics
- Exercise Physiology
- Public Health
Background:
- Physical activity (PA) is crucial for health, yet adults born with very low birth weight (VLBW) exhibit lower PA levels compared to term-born individuals.
- VLBW individuals often present with diminished motor abilities, potentially influencing their engagement in physical activities.
- Understanding the early life origins of PA is essential for developing targeted health interventions.
Purpose of the Study:
- To investigate whether motor abilities mediate the relationship between very low birth weight (VLBW) and objectively measured physical activity (PA).
- To quantify differences in moderate-to-vigorous PA (MVPA), light PA, and sedentary time between VLBW adults and term-born controls.
Main Methods:
- A joint analysis of two longitudinal birth cohorts from Finland and Norway included 87 adults born preterm with VLBW and 109 term-born controls.
- Physical activity was objectively measured using tri-axial accelerometers.
- Motor abilities were assessed using standardized tests, and mediation analyses explored their role in the VLBW-PA association, adjusted for cohort, age, and sex.
Main Results:
- Adults born with VLBW demonstrated significantly lower moderate-to-vigorous physical activity (MVPA), with 40.4 MET min/day less than controls.
- Gross motor abilities partially mediated this association, with an indirect effect of -15.6 MET min/day on MVPA.
- No significant differences were reported for light PA or sedentary time between the groups.
Conclusions:
- Adults born preterm with VLBW engage in less MVPA compared to term-born individuals.
- Gross motor abilities play a mediating role in the reduced MVPA observed in VLBW adults.
- Interventions aimed at improving motor abilities may be a viable strategy to enhance physical activity levels in this population.
Abstract:
Physical activity (PA) is beneficial for several health outcomes. Adults born with very low birth weight (VLBW<1500g) undertake less PA than those born at term, have poorer motor abilities and may serve as a model on early life origins of PA. We therefore examined whether motor abilities mediate the association between being born with VLBW and device-measured PA. In a joint assessment of two longitudinal birth cohorts from Finland and Norway, PA was measured by two tri-axial accelerometers in 87 adults born preterm with VLBW and 109 controls born at term. We explored the mediating role of motor abilities assessed by standardized tests on the association between VLBW and device-measured PA. To do this, we examined group differences in metabolic equivalent of task (MET) min/day of moderate to vigorous PA (MVPA), light PA and sedentary. Analyses were adjusted for cohort, age and sex. MVPA was 40.4 (95% confidence interval [CI]: 13.3 to 69.4) MET min/day lower in the VLBW group than the control group. This was in part mediated through gross motor abilities, indicated by the indirect effect on the association between VLBW and MVPA being -15.6 (95% CI: -28.5 to -5.4) MET min/day. In conclusion, adults born preterm with VLBW undertake less MVPA than controls born at term, and gross motor abilities mediate this association. Interventions targeting motor abilities should be examined as potential ways to increase PA.
