A mismatch in energy is not a character flaw in either dog. One of your pair may be a young, boisterous chaser who plays in loud bursts and crashes afterwards, while the other is an older or quieter dog who enjoys a short game, a long sniff, and an undisturbed bed. Trouble starts when the first dog treats the second as a permanent playmate, and the calmer dog's warnings get sharper over days. The fix is structure, not forced friendship.
Read each dog's play style honestly
Watch what each dog chooses when nobody is directing the game. A dog who loves chase may still hate wrestling; a dog who wrestles happily may guard toys fiercely; a dog who brings a ball to everyone may want fetch, not company. In shared play, relaxed dogs take turns, pause on their own, and shake off tension between bursts. Warning signs that the styles have clashed include one dog always chasing while the other always flees, pinned ears, a tucked tail, lip licking, hiding behind furniture or an owner, growling, and play that gets faster and louder instead of breaking into natural pauses. Believe the dog who is asking for space.
Exercise each dog in the way that dog needs
Meet the energy separately before you ask the dogs to share a room calmly. The high-energy dog usually needs the bigger outing first: a longer walk with running, fetch, or training games, followed by sniffing time that lets excitement drain away. The calmer dog needs the outing they actually enjoy, which may be a slow neighbourhood sniff, a gentle game, and a chew at home. Walk the dogs separately at least some of the time, because a joint walk at one pace under-exercises one dog and over-arouses the other. When both dogs come home pleasantly tired rather than wired, shared time starts several notches calmer.
Supervise shared play with planned pauses
Keep shared sessions short and supervised, in a space where the calmer dog can leave without being cornered. Pause the play often: call each dog away in turn, reward a calm look or a sit, let heart rates drop, and then release them only if both dogs turn back to the game willingly. That willingness check matters, because a dog who walks away, sniffs the ground, or settles on their bed has voted to finish, and the other dog must be called off and occupied elsewhere. Remove toys that either dog guards, end the session while both dogs are still relaxed rather than after a snap, and separate the dogs to rest before tiredness turns into irritability.
Give each dog a real off switch at home
Peace at home depends on places where each dog is genuinely left alone. Give each dog a separate rest area, with their own bed behind a gate, in a crate they choose to use, or in a different room, and enforce the household rule that a resting dog is never pestered by the other. Feed the dogs apart, and give favourite chew toys and long-lasting treats in their separate areas, because food and prized objects turn mild friction into guarding faster than play does.
If the friction is growing
Growling that is becoming more frequent, guarding that spreads to new objects, one dog avoiding whole rooms, or any fight that breaks skin means the arrangement needs more than goodwill. Separate the dogs fully in the home, and book a vet check for the dog whose tolerance has dropped, because pain and illness can shorten a dog's temper and only a vet can examine for that. A qualified behaviour professional can then watch the pair together and rebuild introductions at a pace each dog can handle. Until that help is in place, KinsLe's Care Teams lets you and your roommate log who walked which dog, who supervised play, and who gave each dog their rest break, so the separate routines you agreed actually happen every day.