Only 1% of teens in the Marshall Islands meet daily exercise guidelines, landmark survey finds

A striking national survey of adolescents in the Republic of the Marshall Islands has revealed a portrait of youth health behaviour that few countries anywhere in the world could match for concern. Among nearly two thousand school-going teenagers drawn from every corner of the Pacific island nation, just 0.8 percent met the internationally recommended minimum of at least 60 minutes of moderate- to vigorous-intensity physical activity every day. That figure, reported in a study published in the Journal of Activity, Sedentary and Sleep Behaviors, is among the lowest ever documented for daily physical activity adherence in a nationally representative adolescent sample, and it lands in a region that has long been underrepresented in the global movement behaviour literature. The findings, based on cross-sectional data from the 2023 Marshall Islands Global Youth Tobacco Survey, offer the most detailed baseline yet of how young Marshallese move, sit and sleep, and they arrive at a moment when Pacific Island nations face mounting pressures on the health of their young populations.

The research team, led by Kar Hau Chong and Zoe Power, co-first authors affiliated with the University of Wollongong, together with colleagues including Anthony D. Okely and collaborators in the Marshall Islands, Australia and the United States, analysed questionnaire responses from 1970 students in Grades 7 to 12 across 26 secondary schools. Girls made up 51.6 percent of the analytical sample. The Global Youth Tobacco Survey, administered anonymously and self-completed by students, is not typically associated with physical activity research, yet its structured items on exercise, sedentary time and sleep allowed the investigators to construct a rare nationally representative picture of movement behaviours in a small island developing state. Using survey-weighted descriptive statistics and generalised linear models, the team estimated the prevalence of each behaviour and tested how they varied by sex and age.

The headline number is unambiguous. While only 0.8 percent of adolescents achieved the 60-minute daily threshold of moderate- to vigorous-intensity physical activity, or MVPA, 53.5 percent managed that level of exertion on at least one day per week. The gap between the two figures tells the central story: many Marshallese teenagers do exercise, but almost none sustain it at the frequency and consistency that international guidelines recommend. Confidence intervals around the daily estimate, ranging from 0.4 to 2.0 percent, make clear that even at the upper bound the adherence rate would remain extraordinary low. For a measure that sits at the foundation of paediatric health guidance worldwide, the result signals a population-wide shortfall rather than the failure of a small subgroup.

Beneath the headline figure, the study documented similarly discouraging patterns across the other pillars of healthy movement. Roughly one third of adolescents engaged in muscle-strengthening activities on three or more days per week, with the survey recording 30.4 percent. Active school transport, meaning walking or cycling to and from school, was reported by 32.6 percent on at least three days weekly. Sedentary behaviour told the inverse story: 44.6 percent of adolescents accumulated three or more hours of leisure-time sitting per day, a level the researchers classified as high. Sleep fared little better, with only 44.2 percent meeting the age-specific duration recommendations of at least nine hours for those aged 11 to 13 and at least eight hours for those aged 14 to 18. Taken together, the data indicate that a large majority of young Marshallese fall short on at least one of the three behaviours that jointly define the 24-hour movement guidelines adopted in many countries.

The sex differences mapped onto familiar global patterns but carried distinctive local texture. Boys demonstrated higher participation in moderate- to vigorous-intensity physical activity than girls, consistent with trends seen across most of the world, while girls reported higher levels of sedentary behaviour. The researchers went further than simple comparisons, however, by testing for sex-by-age interactions and finding statistically significant interplay between the two factors across every physical activity behaviour they measured. Older boys, those above 14 years of age, consistently showed higher odds of participation than younger boys. This developmental gradient suggests that whatever drives adolescent boys in the Marshall Islands toward greater activity, it strengthens with age rather than fading, a pattern that could prove important for designing interventions timed to particular school years.

Age itself emerged as a powerful organising variable. Older adolescents, defined in the study as those over 14, generally showed higher participation in moderate- to vigorous-intensity physical activity and higher sedentary behaviour, and they were more likely than younger teens to obtain sufficient sleep. The combination is intriguing: the same group that moves more during the day also sits more and, paradoxically, sleeps better. The authors interpret these divergences as evidence that any effort to promote healthy movement in the Marshall Islands will need to be age- and sex-responsive, since a single uniform programme would miss the very different starting points of a 12-year-old girl and a 17-year-old boy. The findings provide baseline evidence intended to inform future surveillance and targeted strategy development in the nation.

The significance of the study extends beyond the Marshall Islands’ own borders. Pacific nations remain conspicuously underrepresented in the global movement behaviour literature, a gap the authors set out to close. Small island developing states in Micronesia and across Oceania rarely appear in the large multi-country surveillance datasets that shape international guidelines, which means their adolescent populations are often invisible in the evidence base used to allocate global health resources. By drawing on a nationally representative sample and applying rigorous survey-weighted analysis, the study demonstrates that such data can be generated even in nations with small populations and dispersed island geographies, and it establishes a reference point against which future Marshallese surveys, including those based on the Global School-Based Student Health Survey, can be compared.

Methodologically, the study is careful about what its data can and cannot say. As a cross-sectional analysis, it captures a single moment in time and cannot establish causal relationships between age, sex and behaviour. The measures were self-reported, which introduces the possibility of recall and social desirability bias, though the anonymous, self-administered format of the questionnaire is designed to reduce such distortions. The analytical sample of 1970 students came from the 2479 students in Grades 7 to 12 who were invited to participate across 26 secondary schools, and the survey covered school-going adolescents only, meaning those outside formal education were not represented. The survey’s conduct was approved by the Marshall Islands Ministry of Health and Human Services and the Ministry of Education, with passive parental consent obtained before data collection, and the secondary analysis received ethical approval from the University of Wollongong Human Research Ethics Committee.

The behavioural profile documented in the study matters because physical activity, sedentary time and sleep in adolescence are linked in the broader scientific literature to cardiometabolic health, mental wellbeing and the trajectories that carry into adulthood. The Republic of the Marshall Islands, a nation of low-lying atolls in the central Pacific, faces environmental and economic pressures that shape daily life on its islands, and the study’s findings give its health and education ministries a quantified starting point for action. The researchers explicitly frame the work as baseline evidence for surveillance, and the use of the Global Youth Tobacco Survey infrastructure hints at a practical pathway: existing school-based survey mechanisms can carry movement behaviour questions at little additional cost, allowing repeated measurement over time.

What emerges from the data is both a warning and an opportunity. The warning is stark: fewer than one in a hundred Marshallese adolescents meets the daily activity threshold, nearly half sit for three or more leisure hours a day, and more than half do not get the sleep their bodies require. The opportunity lies in the patterns within the numbers. Older boys are already moving more, girls’ higher sedentary time marks a clear target, and the strong age gradients suggest that interventions can be timed and tailored with precision. For a nation whose young people will determine its future, the study provides something indispensable, an honest, nationally representative accounting of where they stand today, and a map of the differences by sex and age that any successful effort to help them move more, sit less and sleep better will need to navigate.

Subject of Research: Prevalence of physical activity, sedentary behaviour and sleep among adolescents in the Republic of the Marshall Islands

Article Title: Prevalence of movement behaviours among adolescents in the Republic of the Marshall Islands: a nationally representative study

Article References: Prevalence of movement behaviours among adolescents in the Republic of the Marshall Islands: a nationally representative study. (n.d.). https://doi.org/10.1186/s44167-026-00118-x

Image Credits: AI Generated

DOI: 10.1186/s44167-026-00118-x

Keywords: physical activity, sedentary behaviour, sleep, adolescents, Marshall Islands, Pacific Islands, Micronesia, public health, surveillance, MVPA, movement behaviours, youth health