Use of "Vigorous" in a sentence [closed]

As to attributive vs. predicative use of vigorous, both are possible:

African dance is vigorous, but full of subtlety.
Sir Robert was a strong and vigorous politician.

[Collins]

The examples also show that vigorous can describe a person (as opposed to activity etc.) The only reservation I have is that, used of a person, it seems to convey their overall temperament, rather than their momentary effort. That is why `Leo is quite vigorous.' sounds somewhat odd to me as a rendering of a picture of someone undertaking a strenuous activity.

Yes, you can use vigorous with the connotation you are suggesting:

very active, determined or full of energy (synonym energetic)

• a vigorous campaign against tax fraud

• a vigorous opponent of the government

• take vigorous exercise for several hours a week.

OLD

The term is a very old one:

Vigorous:

• c. 1300 (early 13c. as a surname), from Anglo-French vigrus, Old French vigoros "strong, robust, powerful" (12c., Modern French vigoreux), from Medieval Latin vigorosus, from Latin vigere "be lively, flourish, thrive" (see vigor).

Etymonline