by brute strength meaning

• [American slang]
  by great muscular strength.
    The men moved the heavy door by brute strength.

• brute:    Noun: brute & ...
• in strength:    In great numbers
• on the strength:    On the muster roll

Examples

1. The game turned from one of finesse and beauty into one dominated by brute strength and its ugly use.
2. For him, politics was a dogfight, but one enhanced as much by cunning and guile as by brute strength and endurance.
3. Two day after the game, Crusinberry wrote a column in the " Chicago Daily Tribune " opining that Michigan's offense was the culmination of the new, less brutish game of football : " The old time player, who did his stuff by brute strength, has given way to the modern man with a head full of tricks . . ..