Depends on how much time you have to devote on those 3 days. All last year I worked at building lean muscle so I could get stronger, yet not overly large so as to have a decent physique and retain my flexibility for golf. I was on a 4 day program, but divided certain areas of the body up on each of those 4 days and always worked those areas on a schedule. I also alternated muscle groups with each lift I did. I.e. Tri's, then Bi then repeat. This way my muscles never got used to what I was lifting. Also, I always did slightly lower weight but a few more reps, 10-12 reps for 3 sets on everything. Added 100 pounds to my bench in a year, much more toned, not huge either. Ran before every lift as well. Many, many workouts can fit what youre looking for though if lifting isnt your thing though.