My dogs can spend the whole day outside sunning themselves. I have to work at making sure they get enough exercise. That is what works for us. I would start by taking the dog to an 8-week obedience class. The dog may simply need a little structure in its life.
Obedience classes tend to have a calming effect on out of control dogs.
Then work the exercises into your everyday life with your dog. Have the dog sit before it gets its food, shake hands for a treat, etc. That way he won't get bored with the same toys all the time. These can keep a dog occupied for hours. If the dog still needs more exercise, attention, and mental stimulation you could try one of the many dog sports out there.