Which of the following is not a safety rule in strength training

Hello. This question is incomplete. The complete question is:

"Which of the following is not a safety rule in strength training?

A. Do not focus too much on one muscle group.  B. Always maintain a slight bend in the knees.  C. Lift and lower weight with controlled movements.  D. Do not hold your breath."

A. Do not focus too much on one muscle group.

Explanation:

Strength training is characterized by a training that focuses on increased recruitment of muscle units, therefore, body strength training will require more muscle fibers to overcome the resistance imposed on it. Some people confuse strength training with hypertrophy, although both increase strength and muscle diameter, but one will give more emphasis than the other. In strength training you will get stronger, hypertrophy will get you bigger.

However, in both strength training and hypertrophy training, some safety rules must be followed so that the athlete does not hurt himself. These rules include: Always keep your knees slightly bent, lift and lower your weight with controlled movements, and do not hold your breath.

"Not focusing too much on one muscle group" is not a safety rule in strength training.

i think its pulmonary not sure tho