This study looks at how exercise can help people with Parkinson's disease (PD) think better and if a type of deep sleep called **slow wave sleep (SWS)** can show how much they improve. SWS is a part of sleep that's important for memory and thinking skills. People with PD often have trouble sleeping, which can make thinking harder. In this study, participants will do exercises called **progressive resistance training (PRT)** for 12 weeks. If their SWS improves, they will continue for another 12 weeks. If not, they will switch to **endurance training (ET)** to see if that helps.

• The study lasts for up to 24 weeks.
• Participants need to be 45 years or older and have a specific type of PD.
• No recent changes in medication and able to exercise safely.