The purpose of this study was to analyse the associations between sports participation, levels of moderate to vigorous physical activity (MVPA) and cardiorespiratory fitness (CRF). The study comprised 310 participants (183 girls and 127 boys) aged 11-18 years. Sports participation was assessed by questionnaire and habitual physical activity (PA) was measured objectively with accelerometers. The 20-m shuttle-run test was used to estimate CRF. Logistic regression analyses were carried out with CRF as the outcome. The odds ratio (OR) for being fit was greater for those who comply with 60 min · day -1 in MVPA (OR = 2.612; 95%confidence interval [CI] = 1.614-4.225) in comparison with those who do not. Participation in competitive sports at club levels increased the chances of being fit (OR = 13.483; 95%CI = 4.560-39.864), independently of MVPA levels. There were positive and significant trends in CRF and objectively measured PA across the levels of engagement in competitive sports (P < 0.05). Concluding, participation in competitive sports at club level is more effective than other organised or non-organised sports to reach healthier levels of CRF and recommend levels of MVPA.