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You've probably had the feeling. Your running shoes are pounding the pavement—then suddenly your pain fades away, and you're feeling euphoric. The runner's high. But that biological perk may be limited to mammals that evolved for endurance exercise—like us. So says a study in the Journal of Experimental Biology. [David A. Raichlen et al., "Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the 'runner's high'"]
Researchers had humans and dogs—both natural-born runners—jog a half hour on a treadmill. Then they sampled their blood for endocannabinoids, some of the compounds thought to trigger the runner's high. As expected, humans and dogs had much higher levels after the run. But when ferrets—a sedentary species—took the same 30-minute trot, they had no spike in those feel-good molecules.
The authors say that's because long-distance running could have helped our hunter-gatherer ancestors find more food—thus increasing their reproductive success. And they speculate that natural selection may have linked up a feel-good reward to that beneficial behavior. These days of course, this ancient trait won't help us find extra calories—but it may encourage us to run 'em off.
—Christopher Intagliata
[The above text is a transcript of this podcast.]
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4 Comments
Add CommentFerrets sedentary? Not during our three decades of having them in our family.
Reply | Report Abuse | Link to this:Non-cursorial" does not mean that ferrets are hammock potatoes for the same reason that a weight lifter or sprinter is athletic. Ferrets are not marathon types of animals. They prefer activities with sudden bursts of great strength, and hate anything monotonous, not a surprise given their lively and curious intellects. Think of them as being mixed muscle with a lot of white muscle like hurtle racers rather than red muscle like marathon runners, and for their boredom think of what what bores a four year old human.
Having respected press like Scientific American use terms such as "sedentary" as you did on your website is dangerous for ferrets.
There are two ways that incorrect depiction endangers ferrets. First, it can cause newbies to miss common ferret illnesses such as insulinoma and cardiomyopathy which often have lethargy as the first symptom. Second, it can lead them into thinking that they can leave ferrets cage-bound. That has two results. It is mentally unhealthy abuse and results in aberrant behaviors sometimes including biting. Plus, poor muscle mass and poor muscle tone in range of mammal studies result in increased rates of many illnesses and worsened vulnerability to accidents.
What do ferrets do for exercise when given the chance? Meltdown carried a television remote a quarter of her weight to the top of our bedroom closet. Later using gravity as a friend by digging her claws into the bodice of a dress and ripping her way down like a pirate movie hero with a knife. Jumpstart, from a sitting position, could uncoil to jump over a barrier which was three feet high. A professional volleyball friend would have loved to manage a proportional plyometric feat. Orville daily moves 2 dozen toys, some weighing more than he does. Warp would appear on the opposite side of the room from where you had just seen her, ditto Wizbang.
White muscle exercise also has emotional rewards, as do mixed muscle exercises like hurtle racing.
Scientifically, it made sense to look at the runner's highs enjoyed by people like our ultra-marathon champ niece, but it does not make sense for anyone, including the university publicity site and Scientific American, to assume that those who prefer other forms of exercise are not athletic, and perhaps the next step would be for the researchers to try to understand the pleasure felt by those who engage in more plyometric forms of activity.
I am very, very disappointed with Scientic American. Apparently, a study was done, a result was found, and the wrong conclusions have been drawn. Someone took the study results for granted, not okay, esespecially for a science publication. What happened to double checking to make sure that the study had been done correctly and that all of the studies conclusions were indeed correct? Just because one animal, dogs in this instance, like to run on a tread mill, in no way infers that other animals will. Personally, I hate tread mills and will not run on one either. That does not make me sedintary!
Reply | Report Abuse | Link to thisFerrets are not sedintary animals by any stretch of the imagination. I have 4 and they are very active little critters! They romp and run around the house and love chasing the cats. MY little girl, Morgana, loves to climb and she will drag off objects larger than herself. This misinformation is dangerous to ferrets. Ferrets are very curious and intellegent creatures and need ample play time, 4 to 6 hours if caged, daily. Posting that ferrets are sedintary could lead some people to believe that ferrets can be caged all day.
If anyone had bothered to take 2 minutes and do a little research about ferrets, they would have found that one of this studies conclusions was completely wrong.
That no fact-checker checked the assertion "ferrets are a sedentary species" makes me wonder how thoroughly S.A. vets these articles. Remember just because someone else somewhere else published this "fact" does not make it true. And this such an obvious error!
Reply | Report Abuse | Link to thisIt's true ferrets do not engage in sustained long distance marathons but neither do cheetahs or jackrabbits. Also, how many thoroughbred horses can sustain racing speeds, or even a canter, for 30 minutes on a treadmill? These researchers clearly need to reassess their definition of "sedentary" and all the a priori assumptions that went with it.
What would interest me is the evolutionary aspect of runners' high in us former tree-swingers, which was not a weight-bearing exercise if I'm not mistaken; instead, running away as newly evolved bipeds from our past must have meant a great change: namely, a lot of rhythmical impact on our enlarging brains, which, as a gentle 'rockababy'-like massage of our brains may well trigger those extra cannabioids..
Reply | Report Abuse | Link to thisThis is why 'walking the walk' also helps re-set a depressed brain, as has been proven scientifically before.