A depressed person attempts to commit suicide by taking a whole bottle of sleeping pills. The pills cause a drastic decrease in the pH. The patient starts having breathing difficulties because the thick and thin filaments within the respiratory muscles are breaking down. 

Explain in depth the correlation between the persons pH and why their respiratory muscles are breaking down. 

Provide details in your explanation and support your answer with facts from your textbook, research, and articles from scholarly journals. Remember to add references in APA format at the end of your post to avoid plagiarism.