In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: Nonpharmacologic concerns can help the Parkinson ' s disease patient achieve and maintain optimal functioning , including daily exercise , physical therapy , and involvement with support groups .
### Output Text:
Nonpharmacologic concerns can help the Parkinson ' s disease patient achieve and maintain optimal functioning , including daily exercise , physical therapy , and involvement with support groups . 