The systematic and repeated completion of physical exercise over prolonged periods can induce physiological and morphological adaptations which can enhance sporting performance. For these adaptations to occur, a well-designed, structured training programme that consistently implements fundamental principles of exercise prescription is required. Furthermore, an effective training programme should carefully account for the effects of fatigue and allow for adequate periods of recovery. These periods of recovery are important for the optimal adaptation and well-being of an athlete and can help stave off maladaptive outcomes such as non-functional overreaching and the overtraining syndrome (OTS). This chapter broadly discusses the topics of training exposure, acute responses, and adaptation and maladaptation. It has a specific focus upon the complex topic of overreaching and OTS, why our current understanding of these complex topics is poor and why it may remain limited in the future. Finally, it touches upon the proactive planning of recovery in training and competition so that more favourable adaptation and performance outcomes can be achieved.