#2 Nutrition is the key to help your dog maintain his vitality and energy levels high. Not all dogs are build the same, meaning that your dogs nutritional needs might differ from another ones. For that reason consulting with the vet is a must, and together you could build the perfect diet for your loving dog.
#3 Although it is true that senior dogs are slower and show lowered levels of energy, that does not mean that you should stop playing with him all together because he is old now. Mental stimulation is as crucial as nutrition for aging dogs. You could go on slow dog walks together or even a swimming together.