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Previous studies have shown that relaxation parameters and fast protein dynamics can be quickly elucidated from 15 N-CEST experiments [1]. Longitudinal R 1 and transverse R 2 values were reliably derived from fitting of CEST profiles. Herein we show that 15 N-CEST experiments and traditional modelfree analysis provide the internal dynamics of three states of human protein DJ-1 at physiological temperature. The chemical exchange profiles show the absence of a minor state conformation and, in conjunction with 1 H- 15 N NOEs, show increased mobility. R 1 and R 2 values remained relatively unchanged at the three naturally occurring oxidation states of DJ-1, but exhibit striking NOE differences. The NOE data was, therefore, essential in determining the internal motions of the DJ-1 proteins. To the authors' knowledge, we present the first study that combines 15 N CEST data with traditional model-free analyses in the study of a biological system and affirm that more 'lean' model-free approaches should be used cautiously., (Copyright © 2017 Elsevier Inc. All rights reserved.)