Along Lake Pontchartrain they have plenty of biking and jogging trails. It's great scenary while getting some great exercise or training.
Also, along the parks of the shore there are plenty of green grassy areas for sports games and I even saw women doing yoga in one of the gazebos. Areas for kids to play on playground equipment as well.
Equipment: Biking equipment, equipment for tossing or playing ball, yoga equipment?
St. Tammany Parish is sort of like Harris County in Houston. It houses many different smaller cities. At least that's what I'm equating it with. In support of the beautiful landscape the parrish built 31 miles of connecting pavement for those to enjoy the tall pine trees and weather the area allows.
The Trace connects Covington, Mandeville, Abita Springs and Slidell. At each of the cities there is a Trailhead with places to use the restroom and facilities. There are also other attractions. I listed more pictures and information in my Things To Do Tips for each city.
The parrish and cities keep these trails upkept and beautiful. I have the 31-mile path on my list of things to do. But I was somewhat injured when I visited.
I also learned in Mandeville you can rent bikes to do the biking. I did not see them at Covington, Slidell or Abita Springs, though.
Equipment: Will need bike, water for the heat, and any safety equipment.