Here we propose an improved exchange model of proton relaxation to describe hydrogen mobility in intermetallic hydrides. The model has been successfully applied to a number of hydrides of ternary Ti–V–Cr alloys of different composition, namely, TiV0.8Cr1.2, Ti0.5V1.9Cr0.6 and Ti0.5V1.9Cr0.6 + 4 wt.% Zr7Ni10. It has been found that (i) there are two non-equivalent states of hydrogen (with different mobility) and (ii) there is an exchange between these two states. By analyzing proton relaxation and Knight shift data it was possible to estimate the exchange time between these states: 0.02 ms