Physical activity behaviours in adolescence: current evidence and opportunities for intervention.

Young people aged 10-24 years constitute 24% of the world's population; investing in their health could yield a triple benefit-eg, today, into adulthood, and for the next generation. However, in physical activity research, this life stage is poorly understood, with the evidence dominated by research in younger adolescents (aged 10-14 years), school settings, and high-income countries. Globally, 80% of adolescents are insufficiently active, and many adolescents engage in 2 h or more daily recreational screen time. In this Series paper, we present the most up-to-date global evidence on adolescent physical activity and discuss directions for identifying potential solutions to enhance physical activity in the adolescent population. Adolescent physical inactivity probably contributes to key global health problems, including cardiometabolic and mental health disorders, but the evidence is methodologically weak. Evidence-based solutions focus on three key components of the adolescent physical activity system: supportive schools, the social and digital environment, and multipurpose urban environments. Despite an increasing volume of research focused on adolescents, there are still important knowledge gaps, and efforts to improve adolescent physical activity surveillance, research, intervention implementation, and policy development are urgently needed.

Adolescent Health Series: The health of adolescents in sub-Saharan Africa: Challenges and opportunities.

OBJECTIVE: This article provides a concise overview of the current challenges that adolescents face in sub-Saharan Africa, summarises possible solutions and ongoing efforts to implement these, and briefly introduces the subsequent papers of this series. METHODS: We draw on data from the WHO Maternal, Newborn, Child and Adolescent Health and Ageing Data Portal. RESULTS: The opportunity provided by the growing number of adolescents in sub-Saharan Africa will only be realised if they survive, are healthy, receive a quality education and remain in Africa rather than joining the increasing out-migration exodus. Fortunately, there is an increasing focus on adolescent health and well-being both globally and in sub-Saharan Africa, and growing knowledge of what to do to promote adolescent health and well-being and how to do it, and a powerful resource in the form of adolescents themselves. CONCLUSION: There is no time to lose. African adolescents demand it, but are also ready to be part of the solution.

Levels of domain-specific physical activity at work, in the household, for travel and for leisure among 327 789 adults from 104 countries.

OBJECTIVE: To compare the country-level absolute and relative contributions of physical activity at work and in the household, for travel, and during leisure-time to total moderate-to-vigorous physical activity (MVPA). METHODS: We used data collected between 2002 and 2019 from 327 789 participants across 104 countries and territories (n=24 low, n=34 lower-middle, n=30 upper-middle, n=16 high-income) from all six World Health Organization (WHO) regions. We calculated mean min/week of work/household, travel and leisure MVPA and compared their relative contributions to total MVPA using Global Physical Activity Questionnaire data. We compared patterns by country, sex and age group (25-44 and 45-64 years). RESULTS: Mean MVPA in work/household, travel and leisure domains across the 104 countries was 950 (IQR 618-1198), 327 (190-405) and 104 (51-131) min/week, respectively. Corresponding relative contributions to total MVPA were 52% (IQR 44%-63%), 36% (25%-45%) and 12% (4%-15%), respectively. Work/household was the highest contributor in 80 countries; travel in 23; leisure in just one. In both absolute and relative terms, low-income countries tended to show higher work/household (1233 min/week, 57%) and lower leisure MVPA levels (72 min/week, 4%). Travel MVPA duration was higher in low-income countries but there was no obvious pattern in the relative contributions. Women tended to have relatively less work/household and more travel MVPA; age groups were generally similar. CONCLUSION: In the largest domain-specific physical activity study to date, we found considerable country-level variation in how MVPA is accumulated. Such information is essential to inform national and global policy and future investments to provide opportunities to be active, accounting for country context.

Progress in physical activity over the Olympic quadrennium.

On the eve of the 2012 summer Olympic Games, the first Lancet Series on physical activity established that physical inactivity was a global pandemic, and global public health action was urgently needed. The present paper summarises progress on the topics covered in the first Series. In the past 4 years, more countries have been monitoring the prevalence of physical inactivity, although evidence of any improvements in prevalence is still scarce. According to emerging evidence on brain health, physical inactivity accounts for about 3·8% of cases of dementia worldwide. An increase in research on the correlates of physical activity in low-income and middle-income countries (LMICs) is providing a better evidence base for development of context-relevant interventions. A finding specific to LMICs was that physical inactivity was higher in urban (vs rural) residents, which is a cause for concern because of the global trends toward urbanisation. A small but increasing number of intervention studies from LMICs provide initial evidence that community-based interventions can be effective. Although about 80% of countries reported having national physical activity policies or plans, such policies were operational in only about 56% of countries. There are important barriers to policy implementation that must be overcome before progress in increasing physical activity can be expected. Despite signs of progress, efforts to improve physical activity surveillance, research, capacity for intervention, and policy implementation are needed, especially among LMICs.

The World Health Organization STEPwise Approach to Noncommunicable Disease Risk-Factor Surveillance: Methods, Challenges, and Opportunities.

OBJECTIVES: We sought to outline the framework and methods used by the World Health Organization (WHO) STEPwise approach to noncommunicable disease (NCD) surveillance (STEPS), describe the development and current status, and discuss strengths, limitations, and future directions of STEPS surveillance. METHODS: STEPS is a WHO-developed, standardized but flexible framework for countries to monitor the main NCD risk factors through questionnaire assessment and physical and biochemical measurements. It is coordinated by national authorities of the implementing country. The STEPS surveys are generally household-based and interviewer-administered, with scientifically selected samples of around 5000 participants. RESULTS: To date, 122 countries across all 6 WHO regions have completed data collection for STEPS or STEPS-aligned surveys. CONCLUSIONS: STEPS data are being used to inform NCD policies and track risk-factor trends. Future priorities include strengthening these linkages from data to action on NCDs at the country level, and continuing to develop STEPS' capacities to enable a regular and continuous cycle of risk-factor surveillance worldwide.

Relevance of the Sustainable Development Goals (SDGs) to Adolescent Health Measurement: A Systematic Mapping of the SDG Framework and Global Adolescent Health Indicators.

PURPOSE: To assess the relevance of the Sustainable Development Goals (SDGs) framework for adolescent health measurement, both in terms of age disaggregation and different health domains captured, and how the adolescent health indicators recommended by the Global Action for Measurement of Adolescent Health (GAMA) can complement the SDG framework. METHODS: We conducted a desk review to systematically map all 248 SDG indicators using the UN metadata repository in three steps: 1) age-related mandates for SDG reporting; 2) linkages between the SDG indicators and priority areas for adolescent health measurement; 3) comparison between the GAMA indicators and the SDG framework. RESULTS: Of the 248 SDG indicators, 35 (14%) targeted an age range overlapping with adolescence (10-19 years) and 33 (13%) called for age disaggregation. Only one indicator (3.7.2 "adolescent birth rate") covered the entire 10-19 age range. Almost half (41%) of the SDG indicators were directly related to adolescent health, but only 33 of those (13% of all SDG indicators) overlapped with the ages 10-19, and 15 (6% of all SDG indicators) explicitly mandated age disaggregation. Among the 47 GAMA indicators, five corresponded to existing SDG indicators, and eight were adolescent-specific age adaptations. Several GAMA indicators shed light on aspects not tracked in the SDG framework, such as obesity, mental health, physical activity, and bullying among 10-19-year-olds. DISCUSSION: Adolescent health cannot be monitored comprehensively with the SDG framework alone. The GAMA indicators complement this framework via age-disaggregated adaptations and by tracking aspects of adolescent health currently absent from the SDGs.

National, regional, and global trends in insufficient physical activity among adults from 2000 to 2022: a pooled analysis of 507 population-based surveys with 5·7 million participants.

BACKGROUND: Insufficient physical activity increases the risk of non-communicable diseases, poor physical and cognitive function, weight gain, and mental ill-health. Global prevalence of adult insufficient physical activity was last published for 2016, with limited trend data. We aimed to estimate the prevalence of insufficient physical activity for 197 countries and territories, from 2000 to 2022. METHODS: We collated physical activity reported by adults (aged ≥18 years) in population-based surveys. Insufficient physical activity was defined as not doing 150 minutes of moderate-intensity activity, 75 minutes of vigorous-intensity activity, or an equivalent combination per week. We used a Bayesian hierarchical model to compute estimates of insufficient physical activity by country or territory, year, age, and sex. We assessed whether countries or territories, regions, and the world would meet the global target of a 15% relative reduction of the prevalence of insufficient physical activity by 2030 if 2010-22 trends continue. FINDINGS: We included 507 surveys across 163 countries and territories. The global age-standardised prevalence of insufficient physical activity was 31·3% (95% uncertainty interval 28·6-34·0) in 2022, an increase from 23·4% (21·1-26·0) in 2000 and 26·4% (24·8-27·9) in 2010. Prevalence was increasing in 103 (52%) of 197 countries and territories and six (67%) of nine regions, and was declining in the remainder. Prevalence was 5 percentage points higher among female (33·8% [29·9-37·7]) than male (28·7% [25·0-32·6]) individuals. Insufficient physical activity increased in people aged 60 years and older in all regions and both sexes, but age patterns differed for those younger than 60 years. If 2010-22 trends continue, the global target of a 15% relative reduction between 2010 and 2030 will not be met (posterior probability <0·01); however, two regions, Oceania and sub-Saharan Africa, were on track with considerable uncertainty (posterior probabilities 0·70-0·74). INTERPRETATION: Concerted multi-sectoral efforts to reduce insufficient physical activity levels are needed to meet the 2030 target. Physical activity promotion should not exacerbate sex, age, or geographical inequalities. FUNDING: Ministry of Public Health, Qatar, and World Health Organization. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Towards Harmonized Adolescent Health Measurement: Assessing Alignment Between Current Recommendations and the Global Action for Measurement of Adolescent Health-Recommended Indicators.

PURPOSE: This study identified alignment of indicators across different initiatives and data collection instruments as a foundation for future harmonization of adolescent health measurement. METHODS: Using the Global Action for Measurement of Adolescent health (GAMA) recommended indicators as the basis for comparison, we conducted a desk review of 14 global-level initiatives, such as the Sustainable Development Goals and the Global Strategy for Women's, Children's and Adolescents' Health, and five multicountry survey programs, such as the Multiple Indicator Cluster Surveys and the Global school-based Student Health Survey. We identified initiative and survey indicators similar to a GAMA indicator, deconstructed indicators into standard elements to facilitate comparison, and assessed alignment to the corresponding GAMA indicator across each of the elements. RESULTS: A total of 144 initiative indicators and 90 survey indicators were identified. Twenty-four initiative indicators (17%) and 14 survey indicators (16%) matched the corresponding GAMA indicators across all elements. Population of interest was the most commonly discrepant element; whereas GAMA indicators mostly refer to ages 10-19, many survey and initiative indicators encompass only part of this age range, for example, 15-19-year-olds as a subset of adults ages 15-49 years. An additional 53 initiative indicators (39%) and 44 survey indicators (49%) matched on all elements except the population of interest. DISCUSSION: The current adolescent measurement landscape is inconsistent, with differing recommendations on what and how to measure. Findings from this study support efforts to promote indicator alignment and harmonization across adolescent health measurement stakeholders at the global, regional, and country levels.

Indicators to Measure Adolescent Health at the Country, Regional, and Global Levels: Results of a Five-Year Selection Process by the Global Action for the Measurement of Adolescent Health.

PURPOSE: To improve adolescent health measurement, the Global Action for the Measurement of Adolescent health (GAMA) Advisory Group was formed in 2018 and published a draft list of 52 indicators across six adolescent health domains in 2022. We describe the process and results of selecting the adolescent health indicators recommended by GAMA (hereafter, "GAMA-recommended indicators"). METHODS: Each indicator in the draft list was assessed using the following inputs: (1) availability of data and stakeholders' perceptions on their relevance, acceptability, and feasibility across selected countries; (2) alignment with current measurement recommendations and practices; and (3) data in global databases. Topic-specific working groups comprised of GAMA experts and representatives of United Nations partner agencies reviewed results and provided preliminary recommendations, which were appraised by all GAMA members and finalized. RESULTS: There are 47 GAMA-recommended indicators (36 core and 11 additional) for adolescent health measurement across six domains: policies, programs, and laws (4 indicators); systems performance and interventions (4); health determinants (7); health behaviors and risks (20); subjective well-being (2); and health outcomes and conditions (10). DISCUSSION: These indicators are the result of a robust and structured five-year process to identify a priority set of indicators with relevance to adolescent health globally. This inclusive and participatory approach incorporated inputs from a broad range of stakeholders, including adolescents and young people themselves. The GAMA-recommended indicators are now ready to be used to measure adolescent health at the country, regional, and global levels.

Exploring a Preliminary Set of Indicators to Measure Adolescent Health: Results From a 12-Country Feasibility Study.

PURPOSE: To explore data availability, perceived relevance, acceptability and feasibility of implementing 52 draft indicators for adolescent health measurement in different countries globally. METHODS: A mixed-methods, sequential explanatory study was conducted in 12 countries. An online spreadsheet was used to assess data availability and a stakeholder survey to assess perceived relevance, acceptability, and feasibility of implementing each draft indicator proposed by the Global Action for Measurement of Adolescent health (GAMA). The assessments were discussed in virtual meetings with all countries and in deep dives with three countries. Findings were synthesized using descriptive statistics and qualitative thematic analysis. RESULTS: Data availability varied across the 52 draft GAMA indicators and across countries. Nine countries reported measuring over half of the indicators. Most indicators were rated relevant by stakeholders, while some were considered less acceptable and feasible. The ten lowest-ranking indicators were related to mental health, sexual health and substance use; the highest-ranking indicators centered on broader adolescent health issues, like use of health services. Indicators with higher data availability and alignment with national priorities were generally considered most relevant, acceptable and feasible. Barriers to measurement included legal, ethical and sensitivity issues, challenges with multi-sectoral coordination and data systems flexibility. DISCUSSION: Most of the draft GAMA indicators were deemed relevant and feasible, but contextual priorities and perceived acceptability influenced their implementation in countries. To increase their use for a more comprehensive understanding of adolescent health, better multi-sectoral coordination and tailored capacity building to accommodate the diverse data systems in countries will be required.