Wallow, welter, grovel can imply heavy clumsy movement and, when the reference is to man, a debased, pitiable, or ignoble condition.
Wallow basically implies a lurching or rolling to and fro (as of a pig in the mire or a ship in the trough of a wave).
In extended use the term may suggest the state of an animal wallowing in mud and then variously imply complete self-abandonment or absorption or helpless involvement or especially sensual enjoyment and indifference to the defilement or degradation that the condition suggests.
Welter is often employed in place of wallow , but it frequently carries a stronger implication of rolling or tossing helplessly or confusedly or at the mercy of the elements or other external forces.
Welter , however, may not always imply movement, as when it suggests the position of one who has been killed and lies soaked in blood.
Grovel implies a crawling or wriggling with face close to the ground (as in abject fear, awe, self-abasement, or complete humiliation or degradation).