In part two of Gender and Sex, we discuss the ludicrous idea that the Nazis entered a man into the women’s field of running, “nude parades” at the Olympics, the effects of gender transition on athletic performance and grading, rules governing trans-athletes, and a summary of our off-microphone interview with Kai Scott on how running clubs can be more trans-inclusive.
Science Discussed:
The effect of testosterone on red blood cells and natural variability in testosterone
The history of “gender testing” in the Olympics
Latest research on the prevalence of transgender people in the USA
Hormone replacement therapy for transgender people
Trans women run slower after hormone therapy
Adding or blocking testosterone has major effects on muscle mass and hematocrit
Trans women are no faster than cis women
Transgender people have no competitive edge over cis people
Comprehensive list of athletic trans policies
An interview with Chris Mosier, trans athlete.
Wondering how you can make your running club or other athletic team more trans-inclusive?
Check out TransFocus or the Vancouver Frontrunners’ trans policy for an example.
The post Episode 6: Gender and Sex – Part 2 appeared first on SciRunner.
]]>There’s a reason we list gender and sex as separate topics in the title. That’s because, unlike what you might think, it’s not as simple as XX and XY chromosomes leading to male and female bodies which makes men and women. It’s biology–which is a notoriously complicated mess. It’s psychology–even more complicated! And it’s society all wrapped together.
Welcome to a very special edition of the SciRunner podcast featuring our first guest Tessa Fisher. Probably the world’s only queer, trans astrobiologist, the Arizona State University PhD student and avid runner helps Katie and Nigel explore the science and sociology behind gender and running. It’s a long one. So long that we’re actually splitting it into two episodes! Stay tuned for part 2 where we discuss running and transition.
What did we find?
On average, men run faster than women, and the difference seems to be more due to testosterone levels than different body characteristics (e.g. body fat). Sex lies on a spectrum, and the world’s experts on the topic report 20+ ways that someone can be somewhere between male and female. You can have XY chromosomes, have high testosterone levels, but be so insensitive to the effects that your external anatomy is completely female. This makes it hard to define gender categories in runners. In addition, the effects of endogenous (self-produced) testosterone on female running performance aren’t well understood, and don’t seem to have much of an effect.
Science discussed:
Position statement about sex and gender by the American Physiological Society
Male runners are about 14% faster than female runners
Body fat only explains about third of the difference in speed difference between men and women
Male greyhounds only run about 0.7% faster than female greyhounds
Overview of testosterone effects on running performance
Review of gender and running–hematocrit and testosterone.
Review of how sex is a spectrum
Article talking about how there is no single biological criterion for sex
Testosterone levels in female athletes vs. non-athletes
Height and Y chromosomes in female athletes
Olympic policies have led to medically unnecessary treatment of high testosterone in women
The history of gender testing in the Olympics & the IAAF concluding testosterone wasn’t important
Historical intersex conditions and women runners
The post Episode 5: Gender and Sex – Part 1 appeared first on SciRunner.
]]>No shirt, no shoes, no service…. But you might just be able to win an Olympic marathon. Minimalism burst onto the running scene with the publication of Born to Run in 2009, claiming that running barefoot was more natural and would lead to fewer injuries. Since then, the scientific community has been working at catching up, testing to see which claims hold up to scrutiny and which don’t.
It takes the scientific community some time to do their work, so we decided to look at how people’s interest in barefoot running preceded the scientific community’s ability to study it.
So we gauged people’s interest by looking at Google search trends for the phrase “barefoot running”, and found it peaked in 2010. Publications on Web of Science (which only indexes scientific papers) peak in 2014. I kind of suspect if you did a similar analysis for “Atkins diet” you’d probably find something similar. It takes the scientific community time to catch up to all the claims made in the popular press.
So what have scientists found? Well so far it looks like running in minimalist shoes or barefoot doesn’t guarantee you’ll switch to a forefoot landing gait, and while you might get fewer hip or knee injuries, you’ll increase your rate of foot and ankle injuries.
So pick your poison!
Literature cited:
Position statement on barefoot running by the American Podiatric Association
Running shoe technology has progressed for 30 years, but injury rates have not
Stress fractures when you switch to minimalist shoes too fast
Foot bone marrow edema after switching to minimalist shoes
Harvard cross country runners who heelstrike have greater injury risk
Impact forces are greater in Nike Frees (minimalist) than Nike Pegasus (traditional)
Switching shoes doesn’t necessarily mean you’ll switch gait
Western Kenyans who grow up barefoot are more likely to forefoot strike
Plenty of Tarahuamara people heelstrike
There are other Kenyan people and Tanzanian people who grow up barefoot and also heelstrike
People often don’t know how their foot strikes
Minimalist shoes increase rate of injury in a 10 km training program
Barefoot runners have fewer injuries, but run less than traditional shoe wearers
Review of injury risk in barefoot running
The post Episode 4: Minimalism appeared first on SciRunner.
]]>First it starts with a 5K. Next thing you know your child has moved onto a 10K, then a half marathon, then even a full marathon. Spending hours every week feeding this disgusting habit. And by disgusting I mean nipple chafing and foot blisters.
Why do people run? In our last episode we talked about the health benefits of running, which I’m pretty certain a lot of people probably run for that reason, maybe even exclusively, or at least get started for health reasons — but MAYBE lots of people also run because… well… they get high.
What do we conclude?
It seems pretty clear that you can get high from running. Now, whether this is relatively mild changes in pain perception, or slightly elevated mood following running, or getting outright blitzed mid-run seems to vary between runners, but it’s good to know at least the mild form is repeatable! We still don’t really know the mechanisms–there might be endorphins, but that’s a hard thing to be sure of. Endocannabinoids seem like a pretty likely candidate too, but the case is far from settled! The best evidence we have suggests that a 30 minute run at 70-80% of your maximum heart rate (not too fast!) seems to make most runners feel good.
Smoking pot recreationally before running doesn’t seem to have the negative effects you might think it does–since it’s a bronchodilator. But since it also increases heart rate, it doesn’t seem like it would be helpful to smoke up pre race (maybe just for a training run). Whether or not pot is a performance enhancing drug is still being sorted out, but there’s no blaring sign that you *shouldn’t* occasionally smoke up before running if it’s legal in your jurisdiction. Just take ‘er easy.
Studies mentioned in this episode:
Getting the runner’s high is pretty common
Old definition of the runner’s high as a “transcendental” experience
New definition of runner’s high
The runner’s high as a placebo response
People who think the runner’s high is a myth
Blood plasma levels of endorphins increase after exercise
PET study showing possible endorphins in the brain
Naloxone doesn’t block the mood effects of therunner’s high
Naloxone does seem to block some of the pain relieving effects
Review suggests the endorphin hypothesis has little evidence
A review of the endocannabinoid system
First evidence of endocannabinoid release in runners
Review of exercise and the endocannabinoid system
Optimal running dose for endocannabinoid release
Running in adolescence reduces cannabinoid receptors in rats
Knocking out cannabinoid receptors decreases wheel running in mice
Blocking cannabinoid receptors decreases running in mice
Exercise addition and endocannabinoids
Judgement impairment following cannabis use
Cannabis use doesn’t always decrease reaction time
Old Canadian studies on pot use and cycling
Cannabis decreases grip strength
Review of cardiovascular effects of cannabis
Cannabis use increases heart rate
Potential use of cannabis as an anti inflammatory drug
Review of effects of cannabis on exercise performance
Cannabis smoking doesn’t decrease lung function
Cannabis smoking doesn’t seem to have negative lung effects
The post Episode 3: Wanna Get High? appeared first on SciRunner.
]]>Headline, Ottawa Citizen:“RUNNING COULD KILL YOU!”. Men’s Fitness: “HARDER, STRONGER, FASTER RUNNING CAN KILL YOU” Are you scared? ARE YOU SCARED?
Every six months or so, headlines proclaiming the doom of people who like to run seem to pop up like little schadenfreude sundaes. People love to tell runners that all their hard work is likely causing more harm than good, and after the deaths of celebrities like Jim Fixx, Micah True, and even poor old Pheidippides (he of Marathon fame), it is a little scary to contemplate. But how good is the science behind this idea? Are you really likely to die mid-run?
TL:DR version?
Exercise, any exercise at all, is generally good for you. It will increase your lifespan, reduce your risk of diabetes, reduce excess weight, and more. Most people don’t get near enough. Do some people die during marathons? Yes, but it’s unclear whether marathons actually elevate your risk of early death–those people had underlying structural abnormalities or atherosclerosis already. And the clinical significance of any kind of heart damage marker following extreme exercise is unclear–long distance athletes live longer than sedentary or even moderately active people, so it doesn’t appear that these markers mean anything in this population.
Recommendations:
Studies mentioned in the episode:
Pheidippides probably didn’t die
The rate of cardiac arrest in marathons is 1/184,000 participants
Atherosclerotic heart disease tends to be the cause of death during marathons
Marathons prevent deaths from traffic accidents
Cardiovascular disease is the leading cause of death worldwide
Even small amounts of running massively decrease your risk of death from heart disease
Among runners, those who run more need fewer diabetes and cholesterol-lowering drugs
Similarly, more intense running reduces diabetes and cholesterol drug use
Student athletes have fewer heart attacks than the general population
Most people are less active than they think they are
Copenhagen heart health study about risks of strenuous jogging
Running helps prevent diabetes, high blood pressure, and cardiovascular disease
Marathon runners have higher rates of markers of heart damage
Recreational Boston Marathon runners have elevated markers of heart damage following the race
Ironmans do not cause increases in heart damage markers
Recreational Berlin Marathon runners have elevated markers, but no indication of actual heart damage
Elevated heart damage markers following exercise likely are not meaningful
Cardiac arrhythmias are reduced following marathons
Alex Hutchinson attacks the “running too much” myth
Cover photo by mebrett is licensed under CC BY 2.0
The post Episode 2: Running Will Kill You! appeared first on SciRunner.
]]>So after many many unfortunate events that involved a lab flood, a pair of stolen and destroyed glasses, and more rain than any person should have to stand, we’re happy to present our first podcast! Alcohol and running–how they mix, should they mix, and what terrible things might happen in the event of their mixing.
As we produce each podcast, we’ll make sure we link up all the studies we cite in the podcast, so here they are in order of mention.
Did you know you can win an Olympic Marathon while eating a combination of brandy and strychnine? Or that the world mile record while drinking beer is only just a minute slower? Turns out good drinkers can be good runners.
TL:DR version?
It’s not entirely clear what impact alcohol has on athletic performance. It certainly isn’t a great idea to get drunk before running, but moderate alcohol consumption on a general basis will likely not do any harm. You’ll also probably be able to run just fine while moderately hungover, but like any other time you run, gauge how you’re feeling and make sure you’re well hydrated. As for that post-run beer? Keep it to one or two and you won’t be undoing your good work, but it’s probably not a great idea to have more than that (and that’s probably good advice in general!).
Running increases rat ethanol preference
Runners drink more than non-runners
Exercise on any given day increases the chances of consuming alcohol
Drinking before a run is a bad idea
Hangovers don’t decrease running performance the next morning
VERY hungover mice have a harder time running
A small amount of drinking after a run doesn’t cause problems in muscle repair
A larger amount of alcohol can decrease recovery of peak performance
A small amount of alcohol doesn’t change glycogen replenishment, as long as you eat enough
Drinking a small amount of beer after a run doesn’t worsen dehydration
Enjoy all the sciencey goodness!
Cover photo by digboston is licensed under CC BY 2.0
The post Episode 1: Alcohol & Running appeared first on SciRunner.
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