The two weeks before a marathon are, for many runners, the hardest part of training to trust. Mileage drops sharply, sometimes to a third of the peak weeks, at exactly the moment a runner feels strongest and most tempted to squeeze in one more long effort. Coaches call this period the taper, and its purpose is not to build fitness but to let the body absorb weeks of accumulated stress before race day. Runners who ignore the taper and keep pushing volume often arrive at the start line technically fitter on paper but physically depleted, a state that shows up as fatigue somewhere around mile eighteen rather than at the finish.