Replace what the walk actually gave him
A walk tires a dog in three ways: movement, sniffing, and novelty. Your injury may have cut the distance, but the other two can be rebuilt inside a flat, and for mental tiredness they matter more. A dog who has spent twenty minutes searching for scattered food, learning a small trick and watching the street will often settle as deeply as after a moderate walk, because his brain has done a shift. Design each day to include all three elements: something to search, something to learn, and something new to observe.
Feeding becomes the day's main work
Stop serving meals from a bowl for this period and make every ration earn its keep. Scatter kibble through a rolled, knotted towel, hide portions in a muffin tin covered with balls, or spread them across a snuffle mat and cardboard boxes he may shred. Lick mats with a thin smear of his usual wet food, frozen for extra time, give long, calming occupation that asks nothing of your body. Rotate the format so yesterday's puzzle is not solved in seconds today, and feed in several small rounds spread across the day rather than one big session — anticipation between rounds is itself enrichment, structuring his day the way walk times used to.
Training games that work from a chair
Five-minute training bursts, several times a day, tire a dog out of proportion to their length, and most can be run with you seated. Teach a chin rest on your knee, a nose-touch to your palm, finding a named toy among three, or waiting while you hide a treat in plain sight across the room. Keep sessions cheerful and end on a success; learning is the workout, not drilling. If friends or family visit, recruit them for the active versions — gentle indoor fetch down a hallway, tug with rules, hide-and-seek with the person hiding — so your dog also gets the social variety his walks used to provide.
Bring the world to the window
Set up a comfortable watching post by a window with passing life: a bed or platform where he may look out at the street, other dogs and deliveries arriving. Watching is real mental work for a dog, provided it does not tip into frustrated barking at every passer-by — if it does, choose a window with a calmer view, reward quiet watching with food, and close the curtain for set rest periods so observation stays a chosen activity rather than a full-time sentry job. Rotate novel smells into the flat too: a friend's worn fleece, herb sprigs to investigate, a delivery box — each a small edition of the park's news.
Protect rest, and read frustration honestly
A dog on restricted walks needs more sleep, not less, and an owner at home all day can accidentally keep him in perpetual low-level expectation. Keep clear quiet hours with enrichment put away, and expect some frustration behaviour as the routine changes — demand barking, pestering, chewing the wrong thing. Redirect it into the next scheduled game rather than inventing constant entertainment on demand, or you will train him that pestering produces activities. If restlessness keeps escalating despite a full programme, or he stops eating and loses interest in games he usually loves, talk to your vet: pain, including from an injury or condition of his own, sometimes hides behind what looks like boredom.
A written programme your helpers can actually run
On your worst days — pain flares, hospital appointments, sheer exhaustion — even supervising puzzles may be too much, and that is exactly when his programme usually collapses. Write the day's enrichment down as simple tasks anyone can pick up: the morning scatter feed, two seated training bursts, the window session, the evening lick mat. KinsLe helps through Care Teams, where care duties for your dog can be assigned to family members or helpers and marked complete with a timestamp, so a friend calling in can see at a glance which of his mental workouts are done and which still need running.