Impact of Structured Aerobic-Resistance Training on Cardiorespiratory Fitness and Mental Health in Adolescent Students: A Randomized Controlled Trial

Project Abstract

This randomized controlled trial investigates the effects of a structured aerobic-resistance training program on cardiorespiratory fitness (CRF) and mental health outcomes among adolescent students aged 13–17 years. A total of 240 participants from four urban secondary schools were randomly assigned to either an intervention group receiving a 12-week supervised training program (three 60-minute sessions per week) or a control group maintaining their usual physical education curriculum. The aerobic component consisted of interval-based moderate-to-vigorous activities progressing from 20 to 40 minutes per session, while the resistance component incorporated progressive multi-joint exercises using bodyweight and resistance bands, emphasizing muscular strength and endurance. Primary outcomes included CRF measured by maximal oxygen uptake (VO2max) via a treadmill test and 20-meter shuttle run, and mental health assessed using standardized scales for depressive symptoms, anxiety, stress, self-esteem, and overall well-being. Secondary outcomes encompassed anthropometric indices, physical activity levels, sleep quality, academic motivation, and executive function assessed through digital cognitive tasks. Assessments occurred at baseline, immediately post-intervention, and at a 6-month follow-up to evaluate persistence of effects. Data were analyzed using intention-to-treat principles with mixed-effects models to account for repeated measures and clustering by school. The study also examined potential moderators (sex, baseline fitness, BMI percentile) and mediators (changes in CRF and muscular strength) to elucidate mechanisms linking physical activity with mental health outcomes in adolescents. Results indicate that the intervention produced a significant improvement in VO2max (mean difference = 3.8 mL·kg?1·min?1; p < 0.001) and enhanced shuttle run performance compared with controls (p < 0.001). Muscular strength and endurance showed substantial gains in the intervention group (p < 0.01). Mental health outcomes revealed reductions in depressive symptoms and anxiety scores, with medium effect sizes (Cohen’s d ? 0.45–0.60; p < 0.01), alongside improvements in perceived stress and self-esteem (p < 0.05). Overall well-being increased modestly in the intervention arm (p < 0.05). Sleep quality improved but with smaller effect sizes. Mediation analyses suggested that improvements in CRF partially mediated reductions in depressive symptoms and anxiety, while strengthened muscular endurance mediated enhanced self-esteem and well-being. Subgroup analyses showed greater mental health benefits among participants with lower baseline CRF and higher BMI percentile, with no differential effect by sex. The gains in CRF and mental health were largely sustained at the 6-month follow-up, though attenuated by approximately 15–25%, indicating partial persistence without ongoing supervision. The findings demonstrate that a well-structured aerobic-resistance training program can robustly enhance cardiorespiratory fitness and yield meaningful improvements in multiple dimensions of adolescent mental health, with improvements largely maintained beyond the intervention period. The study supports integrating combined aerobic and resistance training into school-based physical activity curricula as a viable strategy to promote physical and psychological well-being during adolescence. Potential limitations include reliance on self-reported sleep and activity measures, and variability in adherence across schools. Future research should explore scalability, long-term maintenance, and cost-effectiveness in diverse educational settings.

Project Overview

What This Project Is About

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The project looks at how a planned mix of aerobic (cardio) and strength exercises affects teenagers’ heart and lung fitness and their mood and stress levels. It tests whether adding resistance training to regular activity provides extra benefits beyond usual gym or PE classes.

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The Problem It Addresses

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Many adolescents have declining fitness and rising mental health concerns. There is limited evidence on combined aerobic and resistance programs in schools and how they influence both physical health and wellbeing. This project aims to fill that gap with a clear, controlled comparison.

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Objectives of the Project

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1. Compare cardiorespiratory fitness between adolescents doing combined training versus usual activities.
2. Assess changes in mental health indicators such as mood, anxiety, and stress.
3. Evaluate adherence and acceptability of the training program.
4. Provide practical recommendations for school-based physical education.

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What You Will Do Step by Step

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1. Recruit a group of eligible students and obtain consent. 2. Randomly assign them to either the combined training group or control. 3. Implement a 12-week training plan with supervised aerobic and resistance sessions. 4. Measure fitness (e.g., endurance tests) before and after, plus simple mental health surveys. 5. Analyze data to compare groups and interpret findings in plain terms.

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Expected Outcome

We expect the training group to show better fitness and improved mood and lower stress than the control group, with good program adherence. Findings could support integrating structured aerobic-resistance programs into school PE to boost both physical health and mental wellbeing.