1. Brisk walking where you feel your heart rate rising, but not to a shortness of breath; and
2. Some hand held bar bells where one does four sets of 10 reputations where the last set is difficult to complete for biceps, triceps, pectorials, and lunges;
3. Five minutes of post exercise stretching.

You can do that in about 50 minutes.

You might also use an eliptical machine to avoid injury but to increase the vitality of your exercise.