workout
Explanation
The Joke
The comic shows a fitness instructor named Sheila in the middle of leading an exercise class. She is doing pushups and her speech bubble reads: "Okay! Let's do those fucking hands-in-the-middle pushups. Nobody likes them but GOD FORBID you have a little arm flab, so let's bob up and down like a room full of shitheads, and ONE, TWO, THREE..."
The caption beneath the panel reads: "Instructor Sheila inadvertently forgets to silence her internal monologue."
The joke is that Sheila is supposed to be an encouraging, motivating fitness instructor, but she has accidentally said out loud what she is actually thinking -- a profanity-laden rant about how pointless and undignified the exercise feels.
The Humor
The humor comes from the universal experience of maintaining a cheerful professional facade while internally feeling completely differently. Fitness instructors are stereotypically upbeat and motivating, shouting encouragement like "You can do it!" and "Feel the burn!" Sheila's actual thoughts reveal the exhaustion and absurdity she sees in the exercises she leads, describing the class as "a room full of shitheads" bobbing up and down. The comedy lies in the contrast between professional expectation and private reality, something everyone who has ever had to be enthusiastic at work can relate to.