Distributions for χ1 in ubiquitin have also been previously reported based on averaging of 3JNCγ and 3JCCγ scalar couplings by (Chou et al. 2003) and are also compared in Table 4. In general, these are in good agreement with those presented with the exception of I3. For this residue, the J-couplings-based analysis predicts important populations for all three rotamers (g+/tr/g− = 0.47/0.21/0.32), in sharp contrast to the dynamic ensembles dominated with only gauche+ rotamers (g+/tr/g− = 1/0/0). The authors explain their result by a “rotameric averaging on a time scale slower than the rotational correlation time (4 ns)”. Our results for this residue rather suggest that the distribution of χ1 rotamers (g+/tr/g− = 0.84/0/0.16) are only slightly modified when taking the supra-τc motions into account.