Purpose

Scant research has investigated whether health promotion interventions have sustained effects in increasing physical activity and healthful diet among adolescents in sub-Saharan Africa, which is experiencing an epidemiological transition from infectious diseases to noncommunicable diseases as leading causes of mortality. We examined whether an intervention increased adherence to 5-a-day diet and physical activity guidelines during a 54-month postintervention period among South African adolescents and whether its effects weakened at long-term (42 and 54 months postintervention) compared with short-term (3, 6, and 12 months postintervention) follow-up.

Methods

We randomized 18 randomly selected schools serving grade 6 learners (mean age = 12.6) in a township and a semirural area in Eastern Cape Province, South Africa, to one of the two 12-hour interventions: health promotion, targeting healthful diet and physical activity; attention-matched control, targeting sexual risk behaviors. We tested the intervention's effects on adherence to 5-a-day diet and physical activity guidelines using generalized estimating equations logistic regression models adjusting for baseline behavior and clustering within schools.

Results

Health promotion intervention participants had higher odds of meeting 5-a-day diet and physical activity guidelines than control participants. The effect on 5-a-day diet did not weaken at long-term compared with short-term follow-up, but the effect on physical activity guidelines was weaker at long-term follow-up, mainly because of a reduced effect on muscle-strengthening physical activity. The intervention also increased health promotion attitude and intention and health knowledge and reduced binge drinking compared with the control group.

Conclusions

A 12-hour intervention in grade 6 shows promise in increasing self-reported adherence to healthful diet and physical activity guidelines during a 4.5-year postintervention period among South African adolescents.

Objective

To determine whether a health-promotion intervention increases South African men's adherence to physical-activity guidelines.

Method

We utilized a cluster-randomized controlled trial design. Eligible clusters, residential neighborhoods near East London, South Africa, were matched in pairs. Within randomly selected pairs, neighborhoods were randomized to theory-based, culturally congruent health-promotion intervention encouraging physical activity or attention-matched HIV/STI risk-reduction control intervention. Men residing in the neighborhoods and reporting coitus in the previous 3 months were eligible. Primary outcome was self-reported individual-level adherence to physical-activity guidelines averaged over 6-month and 12-month post-intervention assessments. Data were collected in 2007-2010. Data collectors, but not facilitators or participants, were blind to group assignment.

Results

Primary outcome intention-to-treat analysis included 22 of 22 clusters and 537 of 572 men in the health-promotion intervention and 22 of 22 clusters and 569 of 609 men in the attention-control intervention. Model-estimated probability of meeting physical-activity guidelines was 51.0% in the health-promotion intervention and 44.7% in attention-matched control (OR=1.34; 95% CI, 1.09-1.63), adjusting for baseline prevalence and clustering from 44 neighborhoods.

Conclusion

A theory-based culturally congruent intervention increased South African men's self-reported physical activity, a key contributor to deaths from non-communicable diseases in South Africa.

Trial registration

ClinicalTrials.gov Identifier: NCT01490359.