A certified Personal Trainer fails to properly spot a client performing heavy incline dumbbell presses and the client injures himself. This is an example of what type of negligence?

Casual is not a legal or professional category of negligence recognized in fitness or tort law.

Serious is a descriptor of severity, not a legal classification of negligence type.

Negligence of omission refers to harm caused by a failure to act - specifically, the absence of a required professional duty. In this case, the trainer did not properly perform the spotting duty during incline dumbbell presses, and that inaction directly led to the client's injury. This is distinguished from commission, which requires an affirmative wrongful act.

Negligence of commission involves actively doing something wrong (e.g., applying improper force), whereas this scenario involves failing to act.