Individuals suffering from brain injury were able to improve their total walking time during rehabilitation with minimal aerobic training. This improvement in walking time along with the improvements in sub-maximal heart rate and VO2 allows for greater work, including ambulation and activities of daily living. It is most likely that the improvements are from greater efficiency and lower energy expenditure, as peak heart rate and VO2 did not change. The varying length of the program also affected peak heart rate and peak VO2 results. Participants only in the program for 6 weeks would not be expected to show an increase in peak VO2 in such a short time. On the other hand, some participants participated for as long as 32 weeks. Their function may have been less to warrant a longer program, but a change in peak VO2 could be expected over that duration. Future studies may use a uniform duration, greater training stimulus, or greater frequency per week to elicit a greater cardiovascular change.