Final answer:
A mechanism leading to muscle imbalance is postural distortions, where poor posture causes continuous muscle exertion out of equilibrium, resulting in muscle strains and increased injury risk. So, correct option is (d).
Step-by-step explanation:
An example of a mechanism that can lead to muscle imbalance is postural distortions. Muscles exert forces to maintain body posture, and poor posture necessitates continuous muscle exertion to balance the body's center of gravity (cg). When individuals have bad posture, such as slouching, the muscles on one side of the body are under constant strain to counterbalance the weight of the upper body, leading to muscle imbalances.
This is because maintaining bad posture creates a torque around the pivot point at the hips, which is counteracted by the muscles in the lower back. Since these muscles have a small mechanical advantage, they must work much harder, resulting in muscle strain and an increased likelihood of injury, such as tendonitis or muscle strains.
Over time, this continuous strain can lead to an imbalance between muscle groups that work excessively and those that do not. The prolonged strain from holding these postures can cause discomfort and even lead to more serious musculoskeletal disorders. Understanding the principles of mechanics can help explain everyday strains in our muscles and bones and demonstrate the importance of maintaining good posture for muscle health and overall bodily function.