This is the 15503rd most frequent German word.
viermal
"Viermal" means "four times" in English.
The word 'viermal' (four times) is an adverb used in this sentence to express the frequency of the action of working out.
Ich habe heute viermal trainiert.
I worked out four times today.
Here 'viermal' indicates the occurrence frequency of the bus schedule within an hour.
Der Bus fährt viermal pro Stunde.
The bus runs four times per hour.
In this sentence, 'viermal' describes how many times the action of reading the book has taken place.