Exploring the Effects of High-Intensity Interval Training on Cardiovascular Fitness Among Senior High School Athletes in Ghana

This study investigated the effect of high-intensity interval training (HIIT) on cardiovascular fitness (CF) among senior high school athletes in Ghana, using VO<sub>2</sub>max as the primary outcome measure, and compared it with a steady-state cardio program (SSCP). A total of 42 student-athletes were randomly assigned to either the HIIT or SSCP group. A mixed-design ANOVA revealed a significant group effect on VO<sub>2</sub>max, <i>F</i> (1, 40) = 12.77, <i>p</i> = .001, η² = .24, indicating greater improvement in the HIIT group. An independent samples <i>t</i>-test showed that post-test VO<sub>2</sub>max scores were significantly higher for the HIIT group than for the SSCP group, <i>t </i>(40)<i> = 7.70, p < .001,</i> 95% CI [1.05, 1.80], with a mean difference of 1.43. Multiple regression analysis further showed that group membership significantly predicted post-test VO<sub>2</sub>max scores, <i>B</i> = 1.43, <i>t </i>(40) = 9.75, <i>p</i> < .001, η² = .71, controlling for 70.9 % of the variance. The findings support the conclusion that HIIT is more effective than SSCP in improving cardiovascular fitness among senior high school athletes in Ghana. This finding suggests that HIIT may be a time-efficient and impactful training strategy for student-athletes seeking to improve aerobic capacity and overall cardiovascular performance. The study provides practical implications for coaches, physical education instructors, and sports performance professionals by demonstrating that shorter, more intense training sessions can yield superior fitness gains compared to traditional steady-state methods. These results support the integration of HIIT into school-based athletic conditioning programmes, especially in contexts where training time, resources, and facilities are limited. Further research is recommended to examine long-term adaptations, sport-specific performance outcomes, and the applicability of HIIT across different age groups and athletic populations in Ghana.