Races American out of blocks? Quite the opposite (6)

'races' is the definition.
The answer and definition can be both to do with motion as well as being verbs in their -s form.
Perhaps you can see an association between them that I don't see?

'american out of blocks? quite the opposite' is the wordplay.
I cannot really understand how this works, but
'american' could be 'am' (abbreviation in some contexts) and 'am' is found within the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
The remaining letters 'ses' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?