One-Line Compression: Three Stalled Months at the Gym

Office worker A went to the gym 5 days a week but saw no change in their body for 3 months. When the trainer checked the workout log, A had been repeating the same weight and the same reps for the whole three months. A stimulus the body has already adapted to no longer produces change. Once A started raising the weight a little each week, muscle mass began to grow in two months. Conversely, coworker B, getting ahead of themselves, raised the weight sharply all at once, injured a shoulder, and rested a whole month. Growth happened only under a load 'a bit tougher than now.'

Read the passage and choose the one sentence that best compresses its core. Traps mixed in include one that generalizes too broadly, one that clings to a minor fact, and one that misses the point.