I'm not sure you have to make it very complicated. It sounds as if you have some basic conditioning which is great. Early studies on aerobics showed that it generally required six weeks from non-active to the start of a training effect (the body begins to use oxygen more efficiently) and then time and distance gains started to climb. You aren't starting from zero so the time to training effect should be shorter. Consider picking a specific distance to run/walk such as 1.5 mi. As you condition the amount of time spent walking will diminish until you are running the entire distance. Then add speed and distance gradually. This will yield a strong aerobic base which is necessary for sustaining energy throughout a training session. Supplement the aerobic training with wind sprints, intervals, etc. to give you better bursts of anaerobic capacity. Weight training, or resistance training can add substantial speed to your techniques. Particularly if the training mimics the muscle groups used for kicking, punching, jumping etc.
