Many debates on tactical fitness focus on the question of which exercises or routines are the most effective. We believe this is the wrong question to be asking. The more important question is, how do we measure whether a fitness program actually improves effectiveness in a given mission set? In the manual Comprehensive Combat Fitness Training, Special Tactics provides some answers to this question. Part 1 of this three-part article offers five common sense fitness principles that provide a good starting point for thinking about combat fitness.