The longevity of spinal cord injury (SCI) patients has been increasing as a result of improved medical care for diseases that cause acute mortality. The age-related decrease in maximal aerobic work capacity (VO2max) has been theorized as a physiological determinant of maximally achievable lifespan. The relationships of age, neurological level of SCI, and days post-SCI event to VO2max level was assessed in 24 SCI men (SCI injury level ranging from T1 to L1) with a mean age of 26.3 plus/minus 8.3 years, VO2max of 15.0 plus/minus 2.7 ml of O2/kg of body weight/min, and maximum workload of 570.1 plus/minus 133.4 W. Multivariate regression analysis entering independent variable (age, SCI level, and days post-SCI) against dependent variables (VO2max and maximum workload) indicated that age significantly affected VO2max (beta = -0.4021, p = 0.05) and maximum workload was affected by age (beta = - 0.3609, p = 0.02), level of SCI (beta = -0.3550,p = 0.02), and days post-SCI (beta = 0.5779, p = 0.0008). The regression coefficient relating increasing age to decreases in VO2max level is similar to findings in non-SCI subjects, and indicates that given a typically low VO2max level for SCI patients, theoretical survival beyond 30 years after injury for the post-SCI patient is unlikely. These findings have important implications for designing SCI programs and for the study of longevity. The longevity of spinal cord injury (SCI) patients has been increasing as a result of improved medical care for diseases that cause acute mortality. The age-related decrease in maximal aerobic work capacity (VO2max) has been theorized as a physiological determinant of maximally achievable lifespan. The relationships of age, neurological level of SCI, and days post-SCI event to VO2max level was assessed in 24 SCI men (SCI injury level ranging from T1 to L1) with a mean age of 26.3 plus/minus 8.3 years, VO2max of 15.0 plus/minus 2.7 ml of O2/kg of body weight/min, and maximum workload of 570.1 plus/minus 133.4 W. Multivariate regression analysis entering independent variable (age, SCI level, and days post-SCI) against dependent variables (VO2max and maximum workload) indicated that age significantly affected VO2max (beta = -0.4021, p = 0.05) and maximum workload was affected by age (beta = - 0.3609, p = 0.02), level of SCI (beta = -0.3550,p = 0.02), and days post-SCI (beta = 0.5779, p = 0.0008). The regression coefficient relating increasing age to decreases in VO2max level is similar to findings in non-SCI subjects, and indicates that given a typically low VO2max level for SCI patients, theoretical survival beyond 30 years after injury for the post-SCI patient is unlikely. These findings have important implications for designing SCI programs and for the study of longevity