Which is the better exercise?

[peppercornrent]

It's vile here today so I took my dog out for 12 minutes. He ran just over a mile in a field this time (got to love a tracker!). If he was on a lead and walked for a mile, it would take 3x longer. Which is more beneficial for the dog? The ability to run around for a short time or a longer slower walk?

Both are equal beneficial imo.

Misread post but sniffing about is best imo. It’s excellent mental stimulation for them.

Depends on your dog and the breed.
A huskies or Dalmatians, for example are built to do long distances at a trott so lead walking would be more beneficial.

A Whippet or Greyhound is a sprinter so 12 minutes running at high speed is more beneficial.

Dogs need to to be able to trot and run and generally move freely. It's incredibly good for them in all sorts of complex ways - for their minds as well as their bodies.

Walking a mile would take you about 20 mins. If you can let your dog free run for that long, it will more beneficial to him than 12 minutes (so long, of course, as he is fit and well, and able to cope with the conditions).