Long-term low-dose alcohol intake promotes white adipose tissue browning and reduces obesity

Tuesday, August 23rd, 2022

There are numerous pieces of evidence indicating that moderate alcohol intake has a protective effect on metabolic diseases:

Our previous studies revealed that long-term low-dose alcohol intake resists high-fat diet (HFD) induced obesity. A process in which white adipose tissue can be stimulated and turned into heat-producing brown adipose tissue named white adipose browning is associated with energy expenditure and weight loss. In this study we aimed to investigate whether alcohol causes the browning of white adipose tissue and whether the browning of white adipose tissue is involved in the resistance to the occurrence of obesity caused by long-term low-dose alcohol intake. After eight months of alcohol feeding, the body weight of mice had no significant change, but the fat content and lipid deposition in the liver were reduced. Morphological observations revealed that the browning of white adipose tissue occurred.

[...]

Moderate alcohol drinking mice had faster lipid metabolism and slower lipid anabolism. In addition, we found that long-term low-dose alcohol intake prevented the increase of body weight, triglycerides, inflammation and energy expenditure decrease induced by HFD. Moderate alcohol consumption increased the expression of UCP1 and glucose uptake in the adipose tissue of the HFD group. In conclusion, our results show for the first time that alcohol can trigger the browning of white adipose tissue to counteract obesity.

Sauna bathing demonstrated a substantially supplementary effect on CRF, systolic BP, and total cholesterol levels

Monday, August 15th, 2022

Regular exercise and sauna bathing have each been shown to improve cardiovascular function in clinical populations:

However, experimental data on the cardiovascular adaptations to regular exercise in conjunction with sauna bathing in the general population is lacking. Therefore, we compared the effects of exercise and sauna bathing, to regular exercise using a multi-arm randomized controlled trial. Participants(n = 47) aged 49 ± 9 years with low physical activity levels, and at least one traditional CVD risk factor were randomly assigned (1:1:1) to guideline-based regular exercise and 15-minute post-exercise sauna (EXS), guideline-based regular exercise (EXE), or control (CON), for eight weeks. The primary outcomes were blood pressure (BP) and cardiorespiratory fitness (CRF). Secondary outcomes included fat mass, total cholesterol levels, and arterial stiffness. EXE had a greater change in CRF (+6.2 ml/kg/min; 95% CI, +4.2. to +8.3 ml/kg/min) and fat mass, but no differences in BP when compared to CON. EXS displayed greater change in CRF (+2.7 ml/kg/min; 95% CI, +0.2. to +5.3 ml/kg/min), lower systolic BP (-8.0 mmHg; 95% CI, -14.6 to -1.4 mmHg) and lower total cholesterol levels compared to EXE. Regular exercise improved CRF and body composition in sedentary adults with CVD risk factors. However, when combined with exercise, sauna bathing demonstrated a substantially supplementary effect on CRF, systolic BP, and total cholesterol levels. Sauna bathing is a valuable lifestyle tool that complements exercise for improving CRF, and decreasing systolic BP. Future research should focus on the duration, and frequency of exposure to ascertain the dose-response relationship.

Why that new “science-backed” supplement probably doesn’t work

Sunday, August 14th, 2022

In much the same way that everything in your fridge both causes and prevents cancer, Alex Hutchinson notes, there’s a study out there somewhere proving that everything boosts endurance:

A new preprint (a journal article that hasn’t yet been peer-reviewed, ironically) from researchers at Queensland University of Technology in Australia explores why this seems to be the case, and what can be done about it. David Borg and his colleagues comb through thousands of articles from 18 journals that focus on sport and exercise medicine, and unearth telltale patterns about what gets published—and perhaps more importantly, what doesn’t. To make sense of the studies you see and decide whether the latest hot performance aid is worth experimenting with, you also have to consider the studies you don’t see.

[...]

One way to illustrate these results is to plot something called the z-value, which is a statistical measure of the strength of an effect. In theory, if you plot the z-values of thousands of studies, you’d expect to see a perfect bell curve. Most of the results would be clustered around zero, and progressively fewer would have either very strongly positive or very strongly negative effects. Any z-value less than -1.96 or greater than +1.96 corresponds to a statistically significant result with p less than 0.05. A z-value between -1.96 and +1.96 indicates a null result with no statistically significant finding.

In practice, the bell curve won’t be perfect, but you’d still expect a fairly smooth curve. Instead, this is what you see if you plot the z-values from the 1,599 studies analyzed by Borg:

Borg Distribution of Z Values

There’s a giant missing piece in the middle of the bell curve, where all the studies with non-significant results should be. There are probably lots of different reasons for this, both driven by decisions that researchers make and—just as importantly—decisions that journals make about what to publish and what to reject. It’s not an easy problem to solve, because no journal wants to publish (and no reader wants to read) thousands of studies that conclude, over and over, “We’re not yet sure whether this works.”

Participants lost one-fifth of their body weight

Tuesday, June 7th, 2022

In a 72-week trial in participants with obesity, tirzepatide — a novel glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist — provided substantial and sustained reductions in body weight. Participants lost one-fifth of their body weight.

Boxing and jiu-jitsu have always seemed more important than any training in marksmanship

Wednesday, April 20th, 2022

I stumbled across an MSNBC opinion piece arguing that fitness-fascists have been recruiting and radicalizing young men with neo-Nazi and white supremacist extremist ideologies. I rolled my eyes, but I was legitimately surprised by this bit:

In “Mein Kampf,” Hitler fixated on boxing and jujitsu, believing they could help him create an army of millions whose aggressive spirit and impeccably trained bodies, combined with “fanatical love of the fatherland,” would do more for the German nation than any “mediocre” tactical weapons training.

I’m honestly shocked that I did not know this, since I’m interested in both military history and martial arts. Here’s the offending passage (from 1925):

Now if the SA could be neither a military combat organization nor a secret league, the following consequences inevitably resulted

1. Its training must not proceed from military criteria, but from criteria of expediency for the party.

In so far as the members require physical training, the main emphasis must be laid, not on military drilling, but on athletic activity. Boxing and jiu-jitsu have always seemed to me more important than any inferior, because incomplete, training in marksmanship. Give the German nation six million bodies with flawless athletic training, all glowing with fanatical love of their country and inculcated with the highest offensive spirit, and a national state will, in less than two years if necessary, have created an army, at least in so far as a certain basic core is present. This, as things are today, can rest only in the Reichswehr and not in any combat league that has always done things by halves. Physical culture must inoculate the individual with the conviction of his superiority and give him that self-confidence which lies forever and alone in the consciousness of his own strength; in addition, it must give him those athletic skills which serve as a weapon for the defense of the movement.

Naturally, anyone recommending physical fitness or martial arts is basically Hitler. (Same with vegetarians, of course.)

How little of this is enough?

Monday, February 14th, 2022

Swedish speedskater Nils van der Poel dominated the 10,000-meter race Saturday and then released a training guide for anyone who wants to get on his level:

A friend of mine thinks that my success is mostly based on me being a talent. That the training plan that devoured me wouldn’t give anyone else the same results. Perhaps he’s right, perhaps he’s not. I actually think that he is a little right and a little wrong. I like to think that I earned my success. I also wish for the sport to keep developing and for my records to be broken. I will not be the one to break 6.00,00 nor 12.30,00, but maybe someone else will. For those who might want to, I wrote this document. It’s basically a summary of how I trained from May 2019 to February 2022.

[…]

During my last two seasons I regularly skated 240 laps of 30,0 weekly, alone and with lane change. I believe that I am the only skater ever to be able to do that continuously. I was not born this way, I worked for it. From May 2019 up until August 2020 I abstained from competitions on ice and instead aim my powers at developing a strong aerobic base that enabled me to, later on, perform more high intensity work than ever before. The physical ability that enabled my success was a very strong aerobic base.

[…]

Some pro athletes say that, since they are professionals and can train as much as they like, they might as well add some weight training, and some stretching, and some core, and some technical sessions, and some training competitions, and some coordination sessions… All training sessions are performed at the expense of other, more efficient, training sessions, or at the expense of recovery after these sessions. My point isn’t that stretching is useless. If you need to stretch then go ahead and bend over. But do not fool yourself; do not drop hours from the essential sessions in order to perform something that sounds cool or is easy. Yeah, the gym is warm and nice, mirrors everywhere so that you can see your pretty face and attractive muscles. But you’re more likely 50 watts of the required bike threshold to make it below 12.00,00, than you are 50kg in squats from it. I completely cut what I thought were the sub-optimal sessions in order to increase the optimal ones. But, as I’m looking back upon it all, 5 minutes of core and stretching weekly would have been a smart way of staying clear of injury. Those “prehab” sessions I believe should be approached with an attitude of “how little of this is enough?” in order not to get injured nor steal time and effort from the essential sessions. During winter I skated a lot more competition speed laps than any other long distance speed skater, but I did a lot less of any other high intensity training than all the others.

It may indeed be that there is some extremely nuanced sweet spot

Wednesday, January 26th, 2022

Among 14,000 Finnish people who were tracked for 40 years, those who used saunas frequently were way less likely to develop dementia:

Big if true. And that’s an impressively huge study! But let’s start peeling back the layers.

First of all, it wasn’t every sauna enthusiast who reaped the supposed protective effect against dementia; it was specifically those who used a sauna 9-12 times a month. Sauna bathers who hit the wooden bench 5-8 times a month — sorry, no effect. And those who went more than 12 times a month — again, no luck.

That should raise a caution flag in your head. When only a very specific subpopulation in a study experiences a benefit, it may indeed be that there is some extremely nuanced sweet spot. But it is more likely that the researchers collected a lot of data, which in turn allowed them to analyze many different correlations between sauna use and dementia; the more different analyses they can do, the more likely some of those analyses will generate false positives, just by statistical chance. And then, of course, those titillating positive results are the ones that end up at the top of the paper, and in the press release.

The protection against dementia for that 9-12-times-per-month set was big over the first 20 years of the study, and then faded later, so now we’re slicing and dicing data not only by sauna-frequency, but by time. And then there’s temperature. The Finns who saunaed in temperatures hotter than 100°C (212°F) actually had a higher risk of dementia than those who sauna-and-chilled below 80°C (176°F).

So if you want to prevent dementia, hit the sauna precisely 9-12 times a month at below 80°C — and, unfortunately, expect the protective effect to diminish in the future. Whew!

The two inferior techniques largely rely on pushing down against the water

Saturday, October 16th, 2021

Alex Hutchinson reviews a recent study on the physiology of treading water efficiently:

They put 21 volunteers, all experienced water polo players, synchronized swimmers, or competitive swimmers who self-identified as water treading experts, through a series of physiological and cognitive tests while performing four different styles of treading. The verdict: some techniques really are substantially better than others.

The four techniques are as follows:

  1. Running in the water: This one is pretty self-explanatory. Hands and feet are moving up and down in a running-like motion.
  2. Flutter kick: Your hands are sculling back and forth along the surface of the water, while your legs do a flutter kick.
  3. Upright breaststroke: Your hands are still sculling along the surface of the water, but your legs are doing the distinctive frog kick of the breaststroke.
  4. Eggbeater: It’s similar to the upright breaststroke, with the key difference that your legs are kicking one at a time instead of synchronously, producing an eggbeater pattern of alternating circles with each leg.

[...]

There were clear differences in how efficient the different techniques were, with running and flutter kick performing equally poorly, and upright breaststroke and eggbeater performing equally well. This pattern showed up in every outcome measure.

[...]

Normally VO2 measurements are adjusted for weight, since heavier people burn more energy — but in this case, wet weight was used to also account for differences in buoyancy.

[...]

The two inferior techniques largely rely on pushing down against the water to move the body upward. This has two problems: water is too thin to provide much support, and even when the pushing works you get a lot of wasted up-and-down motion. The two better strokes, in contrast, involve lateral movements of the arms and legs: your cupped hand acts like an airplane wing or sailboat sail, generating lift forces perpendicular to the plane of motion. This is more efficient than pushing on the water, and produces less wasted vertical bobbing.

There’s one key difference between upright breaststroke and the eggbeater: in the former, your legs are kicking outward at the same time, while in the latter they’re alternating. This means that breaststroke produces some of that undesired up (when you kick) and down (between kicks) motion — and that effect is exacerbated if you stop sculling with your hands. In the eggbeater, there’s always one leg moving, so you get a smoother, more continuous lift that can keep you up even without your hands. The study didn’t test anything that required using your arms — but if you want to throw a water polo ball, strike a fancy pose during your synchro routine, or signal frantically to a passing ship that you need rescue, eggbeater looks like a much better bet.

The future elites actually practiced less on average in their eventual sport than the near-elites through most of childhood

Friday, August 13th, 2021

If you look at the average number of hours of deliberate practice between elite and near-elite athletes, David Epstein explains (in The Sports Gene), packing in practice is clearly important, but you need to look at the entire picture:

The future elites actually practiced less on average in their eventual sport than the near-elites through most of childhood. Only in the mid-teen years did they focus in on a single sport and begin racking up practice hours in earnest.

Age vs. Practice Hours per Week

It could be that some eventual elites were simply more gifted and didn’t have to focus in as early.

Or, given the circa-puberty timing of the crossover in the above chart, the future near-elites may simply have been early developers who ceased to stand out when peers caught up physically, and subsequently the near-elites started throwing in the metaphorical towel.

Another possible explanation for this pattern is that early specialization actually hinders development in some sports.

[...]

[NBA MVP Steve] Nash followed a pattern that shows up repeatedly in studies of the childhoods of elite athletes: he had a “sampling period” through about age twelve, where he tried a variety of sports, found the one that best suited him — physically and psychologically — and then focused in during his mid-teen years and got down to business.

[...]

A Swedish study of sub-elite and elite tennis players — five of whom were ranked top fifteen in the world — found that the eventual sub-elites dropped all sports other than tennis by age eleven, whereas the eventual elites continued playing multiple sports until age fourteen. Only at fifteen did the future elites begin to practice more than the future sub-elites.

[...]

A study of the childhoods of musicians shows a similar pattern. In a paper titled “Biological Precursors of Musical Excellence,” psychologists John A. Sloboda and Michael J. A. Howe found that teenagers in a competitive music school who were deemed of “exceptional ability” had, prior to gaining entry to the school, sampled instruments and practiced less and had fewer lessons than students who were deemed of “average ability.” The average students accumulated 1,382 hours of play and practice on their first instrument prior to entering the school, compared to 615 hours for the exceptional students, who only focused on one instrument and ramped up their practice activities later. The average players, the psychologists wrote, “spent more total time on instrumental activity, but devoted the vast majority of their effort to the first chosen instrument.” That is, they stuck rigidly to a single path rather than embracing the sampling period during which athletes and musicians alike apparently often find the route that best fits their inimitable bodies and minds.

This led Epstein to write his next book, Range, which I also recommend — and which I’ve mentioned here before a few times.

They could twist their bodies into positions that you and I can’t

Thursday, August 5th, 2021

Collagen is sometimes referred to as the body’s glue, David Epstein explains (in The Sports Gene), holding connective tissues in proper form:

Biologists at South Africa’s University of Cape Town have been leading the way in identifying genes that predispose exercisers to injuring tendons and ligaments. The researchers focused on genes like COL1A1 and COL5A1 that code for the proteins that make up collagen fibrils, the basic building blocks of tendons, ligaments, and skin.

[...]

People with a certain mutation in the COL1A1 gene have brittle bone disease and suffer fractures easily. A particular mutation in the COL5A1 gene causes Ehlers-Danlos syndrome, which confers hyperflexibility. “Those people in the old days of the circus who used to fold themselves into a box, I bet you in most cases they had Ehlers-Danlos syndrome,” says Malcolm Collins, one of the Cape Town biologists and a leader in the study of collagen genes. “They could twist their bodies into positions that you and I can’t because they’ve got very abnormal collagen fibrils.”

Ehlers-Danlos syndrome is rare, but Collins and colleagues have demonstrated that much more common variations in collagen genes influence both flexibility and an individual’s risk of injuries to the connective tissues, like Achilles tendon rupture. Using that research, the company Gknowmix offers collagen gene tests that doctors can order for patients.

Boxers with an ApoE4 copy scored worse on tests of brain impairment

Sunday, August 1st, 2021

The apolipoprotein E gene comes in a number of common variants, and a single copy of the Apo4 variant is associated with a threefold increased risk of Alzheimer’s, David Epstein explains (in The Sports Gene), but it also extends beyond Alzheimer’s to how well the brain recovers from any injury:

A 1997 study determined that boxers with an ApoE4 copy scored worse on tests of brain impairment than boxers with similar length careers who did not have an ApoE4 copy. Three boxers in the study had severe brain function impairment, and all three had an ApoE4 gene variant. In 2000, a study of fifty-three active pro football players concluded that three factors caused certain players to score lower than their peers on tests of brain function: 1) age, 2) having been hit in the head often, and 3) having an ApoE4 variant.

[...]

What went entirely unmentioned in media coverage, though, was that five of nine brain-damaged boxers and football players who had genetic data included in the report had an ApoE4 variant. That’s 56 percent, between double and triple the proportion in the general population.

Hyperactivity and impulsivity may have had advantages in the ancestral state of man in nature

Wednesday, July 28th, 2021

In The Sports Gene David Epstein reports on a “controversial” hypothesis about ADHD — or “hyperactivity”:

A set of scientists have proposed the controversial idea that hyperactivity and impulsivity may have had advantages in the ancestral state of man in nature, leading to the preservation of genes that increase ADHD risk. Interestingly, the 7R variant of the DRD4 gene is more common in populations that have migrated long distances, as well as those that are nomadic, compared with settled populations.

In 2008, a team of anthropologists genetically tested Ariaal tribesmen in northern Kenya, some of whom are nomadic and some recently settled. In the nomadic group — and only in the nomadic group — those with the 7R version of the DRD4 gene were less likely to be undernourished.

Access to a health club had a comparatively puny influence

Saturday, July 24th, 2021

All sixteen human studies conducted as of the writing of The Sports Gene had found a large contribution of heredity to the amount of voluntary physical activity that people undertake, David Epstein reports:

A 2006 Swedish study of 13,000 pairs of fraternal and identical twins — fraternal twins share half their genes on average, while identical twins essentially share them all — reported that the physical activity levels of identical twins were twice as likely to be similar as those of fraternal twins.

[...]

But another, smaller study of twin pairs that used accelerometers to measure physical activity directly found the same difference between fraternal and identical twin pairs.

The largest study, of 37,051 twin pairs from six European countries and Australia, concluded that about half to three quarters of the variation in the amount of exercise people undertook was attributable to their genetic inheritance, while unique environmental factors, like access to a health club, had a comparatively puny influence.

It is entirely clear that the dopamine system responds to physical activity. This is one reason that exercise can be used as part of treatment for depression and as a method to slow the progression of Parkinson’s disease, an illness that involves the destruction of brain cells that make dopamine. And there is evidence that the reverse is true as well, that physical activity levels respond to the dopamine system.

Normal mice run three to four miles each night

Tuesday, July 20th, 2021

Scientists who bred rodents for their desire to run have proven that work ethic is genetically influenced, David Epstein explains (in The Sports Gene):

Normal mice run three to four miles each night.

[...]

Garland took a group of average mice and separated them into two subgroups: those that chose to run less than average each night, and those that chose to run more than average. Garland then bred “high runners” with other high runners, and “low runners” with other low runners. After just one generation of breeding, the progeny of the high runners were, of their own accord, running even farther on average than their parents. By the sixteenth generation of breeding, the high runners were voluntarily cranking out seven miles each night.

[...]

When mice are bred for endurance capacity — not voluntary running, but when they are forced to run as long as they physically can — successive generations have more symmetrical bones, lower body fat, and larger hearts.

In his voluntary-runner breeding program, Garland saw body changes, “but at the same time,” he says, “clearly the brains are very different.” Like their hearts, the brains of the high runners were larger than those of average mice. “Presumably,” Garland says, “the centers of the brain that deal with motivation and reward have gotten larger.”

[...]

Whatever Ritalin does in the brains of normal mice is already occurring in the brains of the high-running mice.

Where are the runners from Nepal?

Friday, July 16th, 2021

Kenya’s long-distance runners live at altitude, David Epstein notes (in The Sports Gene), but some people ask, “If it’s just the altitude, where are the runners from Nepal?”:

The “Nepali runners” question, though, is actually irrelevant to the Kenyan and Ethiopian running phenomena, and not only because the Himalayan climate does not foster a narrow body type. One clear point of science is that the genetic means by which people in different altitudinous regions of the world have adapted to life at low oxygen are completely distinct. In each of the planet’s three major civilizations that have resided at high altitude for thousands of years, the same problem of survival is met with different biological solutions.

[...]

By the late nineteenth century, scientists figured they understood altitude adaptation. They had studied native Bolivians, living in the Andes at higher than thirteen thousand feet. At that altitude, there are only around 60 percent as many oxygen molecules in each breath of air as at sea level. In order to compensate for the scarce oxygen, Andeans have profuse portions of red blood cells and, within them, oxygen-carrying hemoglobin.

[...]

Andeans have so much hemoglobin that their blood can become viscous and unable to circulate well, and some Andeans develop chronic mountain sickness.

Nineteenth-century scientists also saw that Europeans who traveled from sea level to altitude responded the same way, by producing more hemoglobin.

[...]

Cynthia Beall, an anthropology professor at Case Western Reserve University in Cleveland, started visiting to study Tibetans and Nepalese Sherpas who can live as high as eighteen thousand feet. To her surprise, Beall found that Tibetans had normal, sea-level hemoglobin values, and low oxygen saturation, lower than people at sea level.

[...]

Most Tibetans have a special version of a gene, EPAS1, that acts as a gauge, sensing the available oxygen and regulating the production of red blood cells so that the blood does not become dangerously thick. But it also means Tibetans don’t have the increase in oxygen-carrying hemoglobin that Andeans do.

[...]

Eventually, Beall determined that Tibetans survive by having extremely high levels of nitric oxide in their blood. Nitric oxide cues blood vessels in the lungs to relax and widen for blood flow. “The Tibetans have 240 times as much nitric oxide in the blood as we do,” Beall says. “That’s more than in people at sea level who have sepsis,” a life-threatening medical condition. So Tibetans adapted by having very high blood flow in their lungs, and they also breathe deeper and faster than native lowlanders, as if they’re in a constant state of hyperventilation.

[...]

In 1995, Beall and a team moved on to the remaining population in the world that has lived at high altitude for thousands of years: Ethiopians, and specifically the Amhara ethnic group living at 11,600 feet along the Rift Valley. Yet again, she found an altitude biology unique in the world. The Amhara people had normal, sea-level allotments of hemoglobin and normal, sea-level oxygen saturation.

[...]

But Beall has preliminary data on Amhara Ethiopians that shows they move oxygen unusually rapidly from the tiny air sacs in their lungs into their blood.