ageless-athletes.com has loads of great information on strength training for seniors. The second is Phil Graham, a coach who subscribes to a combination of strength training, cardiovasular work, stretching and intense sprint/interval based training. Graham's book Ready, Set, Go Synergy Fitness is an excellent resource for those wanting to achieve peak fitness and athletic success at any age. I have also incorporated more stretching in my workouts based on the advise from The Stretching Institute, which provides some great stretching resources.
My weekly workouts include four sessions of strength training done Monday, Tuesday, Thursday, and Saturday. I do an alternating two-way split routine - upper body/lower body. I incorporate 20-30 minutes of cardiovascular training either on an indoor recumbent cycling trainer or a rowing machine 2-3 times per week. I do a longer, outdoor training session on my bike, which typically last 2-3 hours in length. Within the overall cardiovascular work, I include two intense sprinting routines called the Sprint 8. I do Sprint 8 either indoors or outdoors.
I call this multi-tasking because I do more than one dimension to my training every session. The multi-tasking approach is described in detail in Phil Graham's book. I often do strength/stretch/cardio in one session, and outdoor cardio/sprint in another, for example. My weekly goal is to do four strength, four cardiovascular (including two Sprint 8), and 3-4 stretching sessions. During my strength training, I am reducing the time between exercise sets to add cardiovascular intensity.
This is admittedly a quite ambitious program. I will report back as to my ability to stay motivated with this program. So far, I am enjoying it very much. My overall fitness is improving. You can see my workout logs on my training blog.