Most owners of reactive dogs walk further than they need to and let their dog sniff less than it needs to. It is an understandable mistake: a tired dog seems like a calmer dog, so the instinct is to add exercise.
For a dog whose arousal is already high, more exercise often makes things worse. What usually helps is the opposite — a shorter, slower, duller walk somewhere nothing is going to happen.
Somewhere quiet and uneventful, on a long line, where your dog sets the pace and chooses where to put their nose. No ball. No training. No agenda.
It sounds like doing nothing. Physiologically it is the opposite of nothing: sniffing engages the seeking system, lowers heart rate and gives a dog something absorbing to do that has no social pressure attached to it.
I use Houndagrip lines because they are not nylon and they have grip, which matters enormously when the line is wet and your dog has just spotted a rabbit. A five-metre line is a good starting point in open ground; three metres is easier on a path.
The best decompression spot is the boring one. Not the popular park, not the dog field at a busy hour. Somewhere with long sight lines, few blind corners, and room to step off the path and let something pass.
I have written up three around Nottinghamshire and Leicestershire that I use with clients for exactly this. See the walks.
Ball play is extremely arousing, and a launcher makes it worse — it requires repeated hard acceleration and sudden stopping, which puts real strain on joints.
That does not mean no ball. It means:
Somewhere quiet, on the long line, no ball, focus on sniffing. Then feed part of the evening meal as a scatter in the grass, or in an enrichment toy at home. Both engage the seeking system and tire a dog mentally in a way that a fast walk does not.
More on enrichment and freework.