This cross-sectional study examined the independent and joint association of fatness and leg power (LP) with resting blood pressure (BP) in adolescents (12 to 15 years) in Benue state of Nigeria. The present study comprised 2047 adolescents, including 1087 girls. Participants were assessed for body mass index (BMI), LP, and resting BP. Multivariate regression models assessing the associations of the independent variables with BP were conducted. Fatness and LP were independent predictors of resting BP among participants and the relationship of LP with BP was more robust in girls than boys. Combined fatness and LP in predicting BP was modest (R2 = 10.4–14.3%) after controlling for maturity status. Low LP was associated with systolic blood pressure (SBP) in both girls (R2 = 9.0%, β = 0.260, p = 0.001) and boys (R2 = 11.0%, β = 0.226, p = 0.001). In the model for diastolic blood pressure (DBP), only fatness was associated with BP in girls (p = 0.001). The odd of hypertension (HTN) risk among overweight girls was 2.6 times that compared to their healthy-weight peers. Girls with low LP were 0.40 times more likely to develop HTN risk compared to their counterparts with high LP. This study has demonstrated that lower body muscle power is more important than fatness in predicting HTN in adolescent boys and girls.