3-6. The physical demands of leadership during repeated deployments or continuous operations can erode how well one thinks and emotional stability, both of which are essential to the effective decision making required for sound leadership. Poor physical fitness multiples the effects of stress, eventually compromising mental and emotional fitness. Operations in difficult terrain, extreme climates, or high altitudes require extensive physical conditioning. Once in the area of operations, leaders must continue efforts to sustain their own fitness and that of their subordinates.