That looked like a straight up setup with one acting as a distraction while another is the aggressor. In this situation being alone is a disadvantage and also learning to travel in pairs could help. Situational awareness is important.

Yes, martial arts, ju jitsu (sp), wrestling, and or self defense class, all would help.

This is also why the 2nd. Amendment is so important. It's proven that an attacker is less threatening with a cap busted off in their ass.