According to aesthetic cognitivism theory, art represents a source of knowledge that promotes understanding, creativity and thinking. However, it remains unclear exactly what kind of art knowledge shapes understanding and thinking. Given the important role played by the arts in acquiring knowledge and facilitating learning and understanding of human culture, this study aimed to shed light on the transformative power of knowledge acquired through art training. Via a pre-registered study, we investigated the extent to which understanding, creative inspiration, thinking, and intellectual challenge judgements are impacted by distinct types of art knowledge training (e.g., in-depth training, brief training or no training), and the extent to which each kind of training generalises to new contexts. Using a training intervention paradigm and a multi-level Bayesian modelling approach, we found that participants (N ~50 per training group) assigned higher ratings of understanding, creativity, and thinking judgements for trained rather than for untrained artworks as a function of art training type. Particularly, in-depth art knowledge training involving visual and auditory descriptions of artworks rather than no training led to greater ratings. The effects of training generalised to unseen artworks produced by the same artist but not to different artists. Compared to the no training group, these effects were most robust for in-depth than brief art training group. These findings suggest that art knowledge training promotes art understanding, creative ideas and thinking, and generalises to new settings that involve a similar artistic style. This work shines a light on the training modality and required duration of art training to shape learning and guide the generalisation effects to novel contexts.