Final answer:
Using large muscle groups when lifting distributes workload more evenly and prevents muscle strain.
Step-by-step explanation:
The rationale for instructing a PCT to use large muscle groups when lifting is that it distributes workload more evenly. When lifting heavy objects, using larger muscle groups, such as the legs and core muscles, allows for a more balanced distribution of the weight, reducing the strain on individual muscles. This can help prevent muscle strain and injury. Additionally, big muscles work more effectively as they are stronger and can generate more force, making lifting tasks easier and more efficient.
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