Exercise is very important to a rabbits health. Opportunities for exercise should be available daily if possible. Rabbits face the possibility of many health related problems should they not receive enough exercise.
For pregnant does, exercise will increase the flow of blood to the babies. Rabbits that do not receive enough play time risk developing GI Statis and other Gastro-Intestinal problems. Urinary tract disease has also been linked to a lack of exercise. The lack of exercise contributes to the weakening of the bladder. The bladder then cannot contract properly and calcium sand is left in the bladder, resulting in bladder stones.
Whatever your choice of available exercise is for your rabbits, supervision is a must. Do not leave your rabbits unattended. Even when you think you have all the bases covered there is a possibility you could have forgotten something.
A room inside your house can be used as an exercise area. Things that need to be removed from the room, would be things like electrical cords, small toys, or other items that you would not want your bunny to chew on. Keep in mind that rabbits like to dig, and can tear up carpet.
Outside runs present their own issues. One of the big items for us are predators. We have plenty of raccoons, opossums, dogs, and hawks that live near us. They would love nothing better than to get a hold of one of our rabbits. Even when we are outside with the rabbits, we will often see the hawks start to circle around. You must also make sure there are some shaded areas where your bunny can get out of the sun. Other things to consider are poisonous plants.
We built a very simple outdoor run for our rabbits. It is connected directly to the side of our barn. We simply used chicken wire and several plastic fence posts. Should we decide to move it, the time required would be very minimal. The side door of the barn is inside the run, so all we have to do is place the bunny inside the run from the side door. We added a sliding wood 1/2 door to block the doorway so that the rabbits don't hop back into the barn and then out the front door. One corner is shaded by use a piece of plywood. The rabbits love being inside the run!
In fact they love being in the run so much, when its their time to come in we sometimes face a little resistance. We will often slowly approach them, crouched down to their level and we are generally able to pick them up. Sometimes more desperate measures are called for like treats!
I know many of you reading this won't need to hear this but, we are careful about the combinations we put in the run. We never put two mature males together in the run. They will fight for territory. We never put a senior doe and a senior buck together, unless we want them to multiply like rabbits! We will let litters run around together. Senior does can be in there together.
Play areas can be enhanced with many of the toys listed in our toy article. Things like cardboard boxes, and cardboard or large diameter pvc tubes can be a fun place for your bunny to play.
Exercise is very important to your rabbits health. They will not get enough exercise in their cage. Keep your rabbit healthy by provided it a place to have fun!