Featured Research

from universities, journals, and other organizations

Runner's high motivated the evolution of exercise, research suggests

Date:
March 22, 2012
Source:
Journal of Experimental Biology
Summary:
Runners often extol the virtues of the runner's high, but now a team of researchers suggest that the runner's high could have evolved to motivate us to exercise as part of our early long-distance nomadic lifestyle.

Runners. Researchers say that endocannabinoids motivated the evolution of exercise.
Credit: Kurhan / Fotolia

In the last century something unexpected happened: humans became sedentary. We traded in our active lifestyles for a more immobile existence. But these were not the conditions under which we evolved. David Raichlen from the University of Arizona, USA, explains that our hunter-gatherer predecessors were long-distance endurance athletes. 'Aerobic activity has played a role in the evolution of lots of different systems in the human body, which may explain why aerobic exercise seems to be so good for us', says Raichlen. However, he points out that testing the hypothesis that we evolved for high-endurance performance is problematic, because most other mammalian endurance athletes are quadrupedal.

Related Articles


'So we got interested in the brain as a way to look at whether evolution generated exercise behaviours in humans through motivation pathways', says Raichlen.

Explaining that most human athletes experience the infamous 'runner's high' after exertion, which is caused by endocanabinoid signalling in the so-called 'reward centres' of the brain, Raichlen adds little was known about the role of endocanabinoids in the other aerobically active mammals. So, he teamed up with Gregory Gerdeman and other colleagues to find out how exercise influences the endocanabinoid levels of two mammalian natural athletes – humans and dogs – and a low activity species – ferrets. The team publish their discovery that animals that evolved for endurance exercise benefit from endocanabinoids while animals that did not don't experience the pleasures, leading them to propose that natural selection used the endocanabinoid system to motivate endurance exercise in humans. The team publishes their discovery in The Journal of Experimental Biology.

Recruiting recreational runners and pet dogs from the local community, Raichlen and Adam Foster trained the participants to run and walk on a treadmill and collected blood samples from the participants before and after the exercise. Unfortunately, the ferrets were less cooperative, so the team collected the ferrets' blood samples after exercise and during rest.

Next, Andrea Giuffrida and Alexandre Seillier analysed the endocanabinoid levels in the blood samples and found that the concentration of one endocanabinoid – anandamide – rocketed in the blood of the dogs and humans after a brisk run. And when the team tested the human runners' state of mind, they found that they athletes were much happier after the exercise. However, when the team analysed the ferrets' blood samples, the animal's anandamide levels did not increase during exercise. They did not produce endocanabinoids in response to high-intensity exercise.

Having suggested that natural selection used the endocanabinoid system to motivate endurance exercise in humans and other animals that walk and run over long distances, Raichlen adds 'These results suggest that natural selection may have been motivating higher rather than low-intensity activities in groups of mammals that evolved to engage in these types of aerobic activities'.

Having found that exercising mammals release pleasurable endocanabinoids in response to exercise, could these brain chemicals be the magic bullet that solves the obesity crisis? Sadly not, says Raichlen, who explains that couch potatoes are not about to leap suddenly out of their comfy chairs and experience the pleasurable effects of exercise, because they probably cannot produce enough endocanabinoids.

He says, 'Inactive people may not be fit enough to hit the exercise intensity that leads to this sort of rewarding sensation.' However, he is optimistic that inactive individuals can be helped to build up their exercise tolerance until they cross the threshold where they become motivated to exercise by endocanabinoids. Raichlen also suggests that exercise could be a cheap solution to many medical conditions, improving our mental state through the endocanabinoids and our cardiovascular and pulmonary condition through good old-fashioned exertion.


Story Source:

The above story is based on materials provided by Journal of Experimental Biology. The original article was written by Kathryn Knight. Note: Materials may be edited for content and length.


Journal Reference:

  1. David A. Raichlen, Adam D. Foster, Gregory L. Gerdeman, Alexandre Seillier and Andrea Giuffrida. Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the ‘runner’s high’. Journal of Experimental Biology, 2012 DOI: 10.1242/​jeb.063677

Cite This Page:

Journal of Experimental Biology. "Runner's high motivated the evolution of exercise, research suggests." ScienceDaily. ScienceDaily, 22 March 2012. <www.sciencedaily.com/releases/2012/03/120322100307.htm>.
Journal of Experimental Biology. (2012, March 22). Runner's high motivated the evolution of exercise, research suggests. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2012/03/120322100307.htm
Journal of Experimental Biology. "Runner's high motivated the evolution of exercise, research suggests." ScienceDaily. www.sciencedaily.com/releases/2012/03/120322100307.htm (accessed October 31, 2014).

Share This



More Health & Medicine News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Fauci Says Ebola Risk in US "essentially Zero"

Fauci Says Ebola Risk in US "essentially Zero"

AP (Oct. 30, 2014) NIAID Director Anthony Fauci said the risk of Ebola becoming an epidemic in the U.S. is essentially zero Thursday at the Washington Ideas Forum. He also said an Ebola vaccine will be tested in West Africa in the next few months. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Nurse Defies Ebola Quarantine With Bike Ride

Nurse Defies Ebola Quarantine With Bike Ride

AP (Oct. 30, 2014) A nurse who vowed to defy Maine's voluntary quarantine for health care workers who treated Ebola patients followed through on her promise Thursday, leaving her home for an hour-long bike ride. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Pot-Infused Edibles Raise Concerns in Colorado

Pot-Infused Edibles Raise Concerns in Colorado

AFP (Oct. 30, 2014) Colorado may have legalized marijuana for recreational use, but the debate around the decision still continues, with a recent - failed - attempt to ban cannabis-infused edibles. Duration: 01:53 Video provided by AFP
Powered by NewsLook.com
British Navy Ship Arrives in Sierra Leone With Ebola Aid

British Navy Ship Arrives in Sierra Leone With Ebola Aid

AFP (Oct. 30, 2014) The British ship RFA ARGUS arrived in Sierra Leone to deliver supplies and equipment to help the fight against Ebola. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins