Spikes Magazine has an interview with Olympic 800m champion Wilfred Bungei, where they discuss a range of topics pertaining to the success of Kenyan athletes. It's a nice, quick read, and two quotes stood out to me as they pertain directly to self-efficacy (the belief in what you can achieve given the effort you put into an activity). Wilfred says:
This is a classic example of self-efficacy built through vicarious experience.
"[My sports teacher] said I had the potential to run. I wasn’t the best [runner] in school and I went home and thought, 'why did he think that I had the potential? Maybe he has seen something in me and this is a reminder to me that you can make it, you can make it'."
This is a perfect example of self-efficacy built through social persuasion.