As humans, we have differentiated ourselves greatly from the rest of the animal kingdom since we stepped out onto the savannah some 100,000 years ago – we use fire, cultivate crops, transform our environment in myriad ways and go to the gym.


Or, to put it another way, we exercise to stay fit. Some of us, anyway.

But now a scientist who studies the physiology of species such as cormorants and king penguins has posed the question – do other animals also ‘train’ in order to prepare themselves for other aspects of their lives?

“I thought it’s an idea worth throwing out there,” said Dr Lewis Halsey of Roehampton University. “Imagine an animal that walks around chewing grass all day, then goes to sleep at night. When it comes to the crunch for that animal – perhaps it has to run away from a predator or fight other males to get a mate, has it got the fitness to do that?”

“If it were a human,” Halsey concluded, “it wouldn’t.”

It would seem that some animals do retain fitness, however, without doing anything.

Barnacle geese, for example, don’t suddenly turn over a fresh leaf at the end of their breeding season and get on their metaphorical ‘flying machines’ in order to prepare for a 2,500km migration.

“Their bodies seem to trigger increased fitness from within,” Halsey said. “Enough to make any human with a waning New Year’s resolution to exercise more very jealous.”

Equally, polar bears wake up from winter hibernation physically strong. King penuins lose a lot of muscle when looking after eggs or chicks on land, but they appear to have no problem going back out to sea to catch fish.

More like this

Keeping fit, or ‘training’, Halsey pointed out, would be a trade off for any animal. Any time and energy spent exercising would mean less time and energy for other things.

“They are trying to maximise their reproductive capacity,” Halsey said, “and the more energy they can funnel through to their offspring, the better.”

In the meantime, Halsey hopes that other scientists will take a fresh look at animal behaviour to see whether anything they witness could be considered ‘exercise’.


Just don’t expect to see a jaguar jogging round the park or a rabbit on a rowing machine.


James FairWildlife journalist