Altitude training places significant stress on an athlete’s physiological systems, therefore athlete monitoring is critical for safely and effectively maximizing the benefits of altitude training. Coaches must diligently track both objective physiological markers and subjective metrics to ensure positive acclimatization and prevent overreaching or illness. Monitoring trends are more important than single data points as single data points mask long-term chronic change. Ultimately, effective monitoring helps coaches determine if the training stimulus is appropriate for adaptation. This evaluation should also consider the smallest worthwhile change—the minimum performance improvement required to meaningfully increase competitive success, ensuring the high investment in altitude training is justified.