This is how the video’s poster describes what’s going on in the footage**:

Курсанты с военной кафедры. Первые тренировки марша с песней.

Funny, right? The second line is particularly revealing.

Just kidding. Here’s the English translation, via Google Translate:

The cadets from the military department. The first workout of the march with the song .

Believe that says it all.

**”Barbie Girl” is a song by Danish-Norwegian dance-pop group “Aqua”. It was hugely popular when Clinton was president.