The Confidence-Fitness Connection: Why Teens Who Get Stronger Also Believe in Themselves

A new study of 618 teenagers reveals that physical fitness and self-confidence grow together—when young people experience success in exercise, their belief in themselves strengthens, which then motivates them to stay active. Researchers from Ecuador's Universidad Espíritu Santo found bidirectional associations between how fit adolescents are and how much they believe in their ability to overcome challenges, suggesting that building physical capacity and psychological resilience aren't separate goals but interconnected parts of healthy development.

What Does the Research Actually Show?

The study, published in February 2026 in the journal Pediatric Investigation, followed 618 boys and girls aged 12 to 17 years in Spain's Region of Murcia. Researchers used objective fitness tests and validated psychological measures to explore whether stronger bodies and stronger minds develop in tandem.

The fitness assessments included five specific tests: a 20-meter shuttle run to measure cardiorespiratory endurance, a standing long jump for lower-body strength, a handgrip dynamometer for upper-body grip strength, a short shuttle sprint for speed and agility, and a sit-and-reach test for flexibility. Self-efficacy—the belief in one's ability to overcome challenges—was measured using the Spanish version of the General Self-Efficacy Scale.

The findings were clear: adolescents with higher cardiorespiratory fitness, greater lower-body muscular strength, and better speed-agility performance reported stronger self-efficacy. The reverse was also true—those with higher self-efficacy scores tended to perform better in these same dynamic fitness domains. Interestingly, flexibility and upper-body grip strength did not show clear associations with self-belief.

Why Does This Connection Matter for Teens?

The timing of this research is significant. Sedentary behaviors, screen exposure, and mental health concerns continue to rise among young people worldwide, making the adolescent years a critical window for establishing healthy patterns. Understanding how physical achievement builds psychological resilience—and vice versa—offers a new framework for supporting teen health.

"Our findings suggest that physical capacity and self-belief are not isolated traits but interconnected elements of adolescent development. When young people experience success in physically demanding tasks, that physical mastery may strengthen their confidence, which in turn encourages further engagement," explained Dr. José Francisco López-Gil, postdoctoral senior researcher at the School of Medicine, Universidad Espíritu Santo.

This insight reframes how we think about fitness programs for teenagers. Rather than viewing exercise as purely a physical health tool, the research suggests that structured physical activity can simultaneously build psychological strength—creating a positive feedback loop where each success motivates further effort.

How to Build Both Fitness and Confidence in Teens

• Structured Fitness Programs: Implement regular exercise routines that include cardiorespiratory training (running, cycling, swimming), lower-body strength work (squats, lunges, jumping), and speed-agility drills. These specific domains showed the strongest associations with self-efficacy in the study.
• Progressive Goal Setting: Help teens set achievable fitness milestones they can track and celebrate. Each completed goal becomes evidence of their capability, reinforcing self-belief and motivating continued participation.
• Positive Reinforcement Strategies: Acknowledge effort and improvement, not just outcomes. Praise the process of pushing harder during a shuttle run or improving their standing long jump distance, which builds confidence in their ability to overcome challenges.
• Psychological Skill-Building: Pair physical training with mental strategies like visualization, positive self-talk, and problem-solving techniques. This integration helps teens connect their physical achievements to broader confidence in handling life's challenges.

What About the Teens Who Struggle With Fitness?

The study's findings also carry an important message for teens who may not naturally excel at physical activity. Because the relationship is bidirectional, building self-efficacy through other means—like setting small, achievable fitness goals or using positive reinforcement—can create momentum that leads to improved physical performance. A teen who believes they can improve their cardiorespiratory fitness is more likely to stick with a running program long enough to actually see results.

The researchers adjusted their statistical models for age, sex, socioeconomic status, body mass index (BMI), physical activity levels, sedentary time, sleep duration, and energy intake to ensure the findings were robust and not explained by other factors. This rigorous approach strengthens confidence in the results.

The Practical Takeaway for Schools and Families

The implications extend beyond traditional physical education classes. Schools and families can leverage this connection by designing fitness experiences that emphasize mastery and progress rather than competition or appearance. When teens see themselves getting stronger, faster, or more agile—and when adults acknowledge these achievements—their belief in their own capabilities grows. That growing confidence then motivates them to stay active, creating a sustainable cycle of health and resilience that extends far beyond the teenage years.