Two separate AI-generated characters appear

Two separate AI-generated characters appear in the same video. both placed inside a professional gym with equipment racks, mirrors, and natural light. The first character is a stocky, dark-haired man in a black performance t-shirt, he demonstrates a seated dumbbell bicep curl, the muscle movement and joint articulation completely natural, then turns to address the camera directly with a coach's authority. The second character is taller and leaner, wet hair, grey tank top, a different physique and energy entirely, he holds a dumbbell in one hand while gesturing to the camera with the other, speaking and pointing as if coaching a session. Two completely different people. Two completely different looks. One production. The gym environment is the same throughout, consistent lighting, consistent equipment, consistent depth of field.