All informal slangy words. "Chops" are your mouth or jaws. "Busting your chops" is an Americanism meaning "exerting yourself", "doing your utmost best". Here "chops" are likely to mean "resilience" or "ability", "power". In normal English, that part if the dialogue means: "You ran impressively fast. I thought for a moment you had what it took to be a runner, until you fell." My advice to you: learn normal English. Use teaching material compiled by qualified education professionals. Forget about learning from this kind of film. It will ruin your English.

Chops often refer to a skill. It's all based on context. If you're in a marathon that it's obvious running is the skill. If you are on the X Factor, then singing well is the skill

Chops can also mean technical skills, for example in music.