Attention Pregnant Couch Potatoes: This is your unborn baby's brain on laziness

A new study suggests exercising during pregnancy could boost an unborn baby's brain development. 

The big bad evidence? 

Researchers in Montreal recruited a group of pregnant couch potatoes. Half exercised for the rest of their pregnancies while the others continued their wanton ways. Within 12 days after giving birth, the mommas dragged the babies, all healthy, thank you, into the lab where each of the latter got stuck wearing a cap teeming with electrodes that would measure electrical activity in their brains. Then the researchers played a soundtrack of mostly low sounds with some occasional "jarring, unfamiliar" ones. Supposedly immature brains react more to startling sounds. Who’d have thunk it, the babies whose mothers exercised exhibited fewer spikes in brain activity in response to the unpleasant sounds. 

Naturally the researchers came to the conclusion gestational exercise promotes brain development. In fact they were so certain they say it right in the title of the study: 

Foetal brain development is influenced by maternal exercise during pregnancy

Don't let the fancy "foetal" distract you. The relationship between fetal brain development and maternal sweating is rather tentative. It involves connecting the dots between a mother's bouts of huffing and puffing to brain changes/growth to spikes in her baby's brain activity months later. The rest of the evidence linking gestational exercise and brain development comes from studies with rats. It isn't clear how this exercise might create changes in fetal brains or how long the supposed effects might last. 

Now this study hasn’t been published yet so I suggest the authors revise a few words. Researchers "test" hypotheses and we all play along like that's the deal. So it's not cool to tell people you set out to "verify" a hypothesis (as opposed to test, explore) even if that’s the case. 

The aim of the present study was to verify if in humans an active lifestyle during pregnancy has an impact on the newborns brain.

Thus it is perfectly clear what the researchers hoped, wished, prayed, designed to find. Despite the stated goal to verify the hypothesis, one of the researchers, Elise Labonte-LeMoyne, a Ph.D. candidate at the University of Montreal, also claimed surprise when the hypothesis was indeed verified according to the New York Times.

“We were surprised,” she said, “by how much of an effect we saw” from barely an hour of exercise per week.

She might not have her Ph.D. yet but she's nailed the Surprised Researcher. OMG! Awesome! I can't believe I got the results I wanted.  

As if that is not enough to worry pregnant woman on sofas everywhere, the NYT couldn't resist the allure of a strong conclusion either. After detailing a few caveats of the research (i.e. the uncertainties, the issues that remain unclear as in not clear) even veteran health writer Gretchen Reynolds had trouble fighting the pull of a solid conclusion, in other words, making something uncertain appear certain. 

Gretchen, be strong ! Don't go there, girlfriend...

But for now, the lesson is clear. 


“If a woman can be physically active during her pregnancy, she may give her unborn child an advantage, in terms of brain development,” Ms. Labonte-LeMoyne said. 


As if "may" makes it all better. Uh, huh. Right. Especially after telling us that “the lesson is clear” meaning this is what the experts know for sure, the crucial takeaway message for mums-to-be, the advice you must heed.

Yes the lesson is clear. The media and researchers alike cannot resist making speculative conclusions seem certain. 

Note: WebMD reports the study involved a mere 18 women, 10 assigned to exercise, 8 to the couch. The study abstract and the New York Times article omitted this detail. As for other news coverage, even the respected Guardian couldn't help but lose it by the subtitle: Weekly exercise by mothers linked to better mental health in later life. In case you're wondering, that refers to the study with the newborns wearing the electrodes and not some survey of depressed, anxious or otherwise irritable middle-aged women who might rant and rave over their computers and steering wheels, on occasion.


Awesome Mom said...

How do they get away with making such sweeping claims with such tiny studies? Time and time again this seems to be the case.

Polly Palumbo, Ph.D. said...

Can I quote you? This was presented at a neuroscience conference in San Diego. There probably is a press release and hey anything about kids and brains makes for good content - and then there's the adorable photo of baby looking like an adorable sea creature in the electrode cap. Voila, NY Times, CBS, LA Times...

Anonymous said...

What I don't understand is the connection between brain reaction to startling sounds and the relationship to "brain development" (implication: smarter brain). Is that a given that I'm not familiar with?

Polly Palumbo, Ph.D. said...

Apparently a infant's reaction to startling or unfamiliar sounds is a marker of brain maturity, rather in this case, immaturity. There must be studies showing infants are less likely to react to these sounds over time.

John Peter said...

This was conferred at a neurobiology conference in San Diego. There in all probability could be a release and hey something concerning youngsters and brains makes permanently content