this video), but he gets tired more easily than an average dog of the same size, so it happens that during long walks he needs some help. thus, the mere act of going around with him provides a good workout: walking, running carrying him around.
this combination of movements is probably one of the oldest types of workout our ancestors used to do in their daily life: going around searching for food, running in case of danger, carrying things.
nowadays humans seem scared of carrying around heavy loads. most of us prefer to take the car if they have to move around with something heavy and that's a pity as a loaded carry is extremely effective for our overall fitness.
basically, walking with weights can be performed in six different ways: putting small weights on wrists or ankles, using a backpack, pulling something heavy, pushing something heavy, the farmer's walk and the waiter's walk. wrists and ankles weights will make you burn more calories without stressing too much your body, a heavy backpack will force you to engage your core muscles while walking, pulling or pushing heavy loads will strengthen your legs and your shoulders. the farmer's walk is one of the easiest and most immediate exercises you can think of: just carry two loads in your hands and move around. it will strengthen your grip, your arms, the stabilizers of your back (the muscles that protect your spine during your daily activities) and will work great on your glutes. doing the waiter's walk is equally easy: just carry something over your head with a straight arm. it will strengthen your back, your arms and it will improve your balance.
every different way of moving with loads has different benefits for our health, and you don't even need to schedule it, it will just happen. walk to the grocery store, push a heavy cart and then load the content in two heavy bags and walk back home: it will be a good combination of pushing something heavy and a farmer's walk. or put everything in a large backpack and you will train your core. if it isn't too embarrassing for you, carry a bag overhead with a straight arm and you'll be performing a waiter's walk. just don' avoid these occurrences (i.e. don't take the car to go shopping for groceries) and walking with weights will naturally become part of your daily routine. it will provide you a free and effective workout that will fit perfectly in your daily activities.
and obviously, adopting a disabled dog is a good choice too.