To analyze the impact of participation in sports with different cardiorespiratory fitness (CRF) demands on changes in metabolic and cardiovascular markers in adolescents . Longitudinal study with 12 months of follow-up (Analysis of Behaviors of Children During Growth [ABCD Growth Study] ). Overall, 184 adolescents (age 15.6 ± 2.1) were classified according to sports participation: non-sport (control), low CRF sports, and high CRF sports . Metabolic outcomes were total cholesterol (TC) and its fractions, triacylglycerol (TG), glucose, insulin levels, and the insulin resistance index . Cardiovascular outcomes were arterial thickness (carotid and femoral [ultrasound] ), blood pressure, and resting heart rate . Adolescents engaged in sports classified as high CRF demand presented a significant increase in HDL-c (1.2 mg/dL [95% CI: -0.5 to 3.0] ) when compared to the non-sport group (-2.4 mg/dL [95% CI: -4.4 to -0.5] ). Regular engagement in high CRF sports was significantly related to changes in TC (β = -0.027 [95% CI: -0.048 to -0.005] ), HDL-c (β = 0.009 [95% CI : 0.001 to 0.019] ), LDL-c (β = -0.032 [95% CI: -0.049 to -0.016] ), and glucose (β = -0.017 [95% CI: -0.025 to -0.008] ), while engagement in low CRF sports was related to changes in TG (β = -0.065 [95% CI: -0.112 to -0.019] ). No significant relationships for cardiovascular parameters were observed in the low CRF group, but one significant relationship was found between high CRF sports and changes in SBP (β = -0.063 [95% CI: -0.117 to -0.009] ). In conclusion, engagement in sports seems to be beneficial for improvements in metabolic and cardiovascular parameters in adolescents, mainly sports with higher CRF demand.