Background Preterm birth with very low birth weight (VLBW; <1500 g) is associated with lower muscle mass in adult life. Although these findings could be related to physical inactivity, little is known about exercise habits in this particular patient group.

Objective To study leisure time physical activity in young adults born with VLBW, compared with term-born controls.

Methods The Helsinki Study of Very Low Birth Weight Adults comprises 166 VLBW and 172 term-born adults, born in 1978–1985. In 2004–2005, at age 18–27 years, the participants attended a clinic study during which their physical and psychological health was assessed. Pre- and postnatal data were obtained from hospital records, and information on current health and physical activity from questionnaires. Individuals (n = 16) with impairments such as cerebral palsy, blindness or developmental delay (conditions related to reduced exercise ability) were excluded from analyses. We used chi-square tests for crude group comparisons, and logistic regression when adjusting for gender, age, and parental education.

Results The VLBW group reported leisure time exercising less frequently than controls (>once weekly: 39.9% vs 60.1%, p = 0.02). Their average exercise duration was shorter (<30 minutes; 15.9% vs 4.7%, p<0.001), and intensity lower (p<0.001). The results remained after adjustment for the aforementioned confounders, and additionally for bronchopulmonary dysplasia. Fewer VLBW adults than controls rated their physical fitness as “good” or “very good” (39.7% vs 60.3%, p = 0.048), although this difference turned non-significant after adjustment.

Conclusion VLBW adults report lower frequency and duration of leisure time exercise than controls. These findings have potential implications for later adult health outcomes.