Introduction: Substantial heterogeneity exists in the cardiorespiratory fitness (CRF) change response to short-term supervised exercise training and its long-term prognostic implication is not well understood. Here, we evaluated the association between the short-term training related changes in CRF and CRF levels 10 years later. Methods: STRRIDE trial participants that were originally randomized to exercise training for 8 months and participated in the 10-year follow up visit were included. CRF levels were measured at baseline, post-training (8 months), and 10-year follow-up as peak oxygen uptake (VO 2 , ml/kg/min) using the maximal treadmill test. Participants were stratified into low, moderate, and high CRF response (CRF-R) groups according to the training-regimen specific tertiles of CRF change from baseline to post-training. Adjusted linear regression models were used to determine the association between short-term change in CRF with training and CRF levels at 10-year follow-up. Results: The study included 80 participants (age = 52 years, 35% women). There was no significant difference in the baseline characteristics of the CRF-R groups. At 10-year follow-up, high CRF-R group had the lowest decline in CRF compared with moderate or low CRF-R groups (-0.005 vs. -2.6. vs. -3.6 ml/kg/min, p = 0.009, Figure). This was largely related to the differential age-related changes in peak oxygen pulse across the three groups (0.58 vs. -0.23 vs. -0.86 ml/beat, p = 0.02) with no difference in the peak heart rate change. In adjusted analysis, high CRF-R was significantly associated with higher CRF levels at follow-up independent of the exercise intervention and other baseline characteristics [High vs. Low (ref) CRF-R: Std β = 0.25; p = 0.004] Conclusion: CRF change in response to short-term training is a significant predictor of age-related CRF decline over long-term follow-up. Thus, training responsiveness may identify individuals at risk for exaggerated CRF decline with aging and associated incidence of cardiovascular diseases.