Flinch

Whenever a character suffers direct damage, they flinch, preventing movement and delaying spells for 0.2 seconds per hit. Spells and abilities that deal their damage in multiple hits also cause their target to flinch multiple times, increasing the delay.

If you are running while hit, your character continues running as soon as they recovered, so a single attack will have little effect at all. However, if you receive a large number of individual hits, the delay adds up, significantly hindering movement.

Flinching can be prevented by using certain abilities, such as a warrior's Endurance, or a priest's Blessing of Fortitude. Dodging attacks entirely does, of course, also prevent flinching.