At a year, my boy was getting roughly 1-2 hrs of exercise a day. We are talking mostly leisurely walks, with some off leash/playtime, obedience training, etc....On longer walks just make sure you give him plenty of breaks.
Does he enjoy playing ball? You can throw a ball for him to retrieve which will also help relieve energy and he gets to rest inbetween. Maybe throw it 3 or 4 times and then do some obedience for 5 minutes to help challenge him mentally.
As for running- The impact of a forced and prolonged run can hurt their forming skeletal structure. 18/24 months is a good age if you intend running with him. Start slow and gradually build up distance and speed.
Kobi is 25 months old now and has a minimum of 1.5hrs exercise daily. Harder and more intense exercise.
They all differ and require varied amounts of exercise. It's about getting the balance right. Not too much, so they are physically exhausted nor too little that they become pent up with frustration through lack of adequate exercise.
It's all down to awareness and moderation. Is he doing too much? Lagging behind on long walks? Appearing to be overtired after the exercise, or sleeping or laying down more than normal? Extreme thirst? These are all signs that he is over exerting himself. You need to be watchful of these signs and know when to cut back.