Identifying athletes who will benefit from altitude training is challenging, as no definitive pretest exists. However, subsequent performance improvement is the most direct, though retrospective, indicator of a positive response. A key challenge lies in differentiating true nonresponders (physiological failure to adapt) from those who simply mismanage their altitude camp. Many elite athletes experience a deceptive sense of well-being at altitude, leading them to overtrain and accumulate excessive fatigue, ultimately resulting in poor postaltitude performance. This overexertion, often exacerbated by the increased physiological stress of hypoxia, masks potential adaptations. Furthermore, a critical factor is the postaltitude period. Failure to include a structured taper/recovery period for a few days after descent can mask performance gains due to acute reacclimation stress. Coaches must closely monitor subjective markers (fatigue, muscle soreness) and objective data (iron status, heart rate) to determine if a poor outcome is a management issue or a biological nonresponse.