I am a fairly strong man.

我的身体相当结实。

《新英汉大辞典》

I am not a strong man, but I know that the time to be strong, and have to pretend to be strong.

我不是坚强的人，但我知道该坚强的时候，装也得装出坚强。

youdao

Luckily I am quite a strong man, so that I was able to satisfy my critical fellow workers.

幸亏我很健壮，能够使那些挑剔的工作伙伴们满意。

youdao