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The coronavirus entered Milwaukee from a white, affluent suburb. Then it took root in the city’s black community and erupted.

As public health officials watched cases rise in March, too many in the community shrugged off warnings. Rumors and conspiracy theories proliferated on social media, pushing the bogus idea that black people are somehow immune to the disease. And much of the initial focus was on international travel, so those who knew no one returning from Asia or Europe were quick to dismiss the risk.


Then, when the shelter-in-place order came, there was a natural pushback among those who recalled other painful government restrictions — including segregation and mass incarceration — on where black people could walk and gather.

“We’re like, ‘We have to wake people up,’” said Milwaukee Health Commissioner Jeanette Kowalik.

As the disease spread at a higher rate in the black community, it made an even deeper cut. Environmental, economic and political factors have compounded for generations, putting black people at higher risk of chronic conditions that leave lungs weak and immune systems vulnerable: asthma, heart disease, hypertension and diabetes. In Milwaukee, simply being black means your life expectancy is 14 years shorter, on average, than someone white.

As of Friday morning, African Americans made up almost half of Milwaukee County’s 945 cases and 81% of its 27 deaths in a county whose population is 26% black. Milwaukee is one of the few places in the United States that is tracking the racial breakdown of people who have been infected by the novel coronavirus, offering a glimpse at the disproportionate destruction it is inflicting on black communities nationwide.

In Michigan, where the state’s population is 14% black, African Americans made up 35% of cases and 40% of deaths as of Friday morning. Detroit, where a majority of residents are black, has emerged as a hot spot with a high death toll. As has New Orleans. Louisiana has not published case breakdowns by race, but 40% of the state’s deaths have happened in Orleans Parish, where the majority of residents are black.

Illinois and North Carolina are two of the few areas publishing statistics on COVID-19 cases by race, and their data shows a disproportionate number of African Americans were infected.

“It will be unimaginable pretty soon,” said Dr. Celia J. Maxwell, an infectious disease physician and associate dean at Howard University College of Medicine, a school and hospital in Washington dedicated to the education and care of the black community. “And anything that comes around is going to be worse in our patients. Period. Many of our patients have so many problems, but this is kind of like the nail in the coffin.”

The U.S. Centers for Disease Control and Prevention tracks virulent outbreaks and typically releases detailed data that includes information about the age, race and location of the people affected. For the coronavirus pandemic, the CDC has released location and age data, but it has been silent on race. The CDC did not respond to ProPublica’s request for race data related to the coronavirus or answer questions about whether they were collecting it at all.

Experts say that the nation’s unwillingness to publicly track the virus by race could obscure a crucial underlying reality: It’s quite likely that a disproportionate number of those who die of coronavirus will be black.

The reasons for this are the same reasons that African Americans have disproportionately high rates of maternal death, low levels of access to medical care and higher rates of asthma, said Dr. Camara Jones, a family physician, epidemiologist and visiting fellow at Harvard University.

“COVID is just unmasking the deep disinvestment in our communities, the historical injustices and the impact of residential segregation,” said Jones, who spent 13 years at the CDC, focused on identifying, measuring and addressing racial bias within the medical system. “This is the time to name racism as the cause of all of those things. The overrepresentation of people of color in poverty and white people in wealth is not just a happenstance. … It’s because we’re not valued.”

Five congressional Democrats wrote to Health and Human Services Secretary Alex Azar, whose department encompasses the CDC, last week demanding the federal government collect and release the breakdown of coronavirus cases by race and ethnicity.

Without demographic data, the members of Congress wrote, health officials and lawmakers won’t be able to address inequities in health outcomes and testing that may emerge: “We urge you not to delay collecting this vital information, and to take any additional necessary steps to ensure that all Americans have the access they need to COVID-19 testing and treatment.”

Milwaukee, one of the few places already tracking coronavirus cases and deaths by race, provides an early indication of what would surface nationally if the federal government actually did this, or locally if other cities and states took its lead.

Milwaukee, both the city and county, passed resolutions last summer that were seen as important steps in addressing decades of race-based inequality.

“We declared racism as a public health issue,” said Kowalik, the city’s health commissioner. “It frames not only how we do our work but how transparent we are about how things are going. It impacts how we manage an outbreak.”

Milwaukee is trying to be purposeful in how it communicates information about the best way to slow the pandemic. It is addressing economic and logistical roadblocks that stand in the way of safety. And it’s being transparent about who is infected, who is dying and how the virus spread in the first place.

Kowalik described watching the virus spread into the city, without enough information, because of limited testing, to be able to take early action to contain it.

At the beginning of March, Wisconsin had one case. State public health officials still considered the risk from the coronavirus “low.” Testing criteria was extremely strict, as it was in many places across the country: You had to have symptoms and have traveled to China, Iran, South Korea or Italy within 14 days or have had contact with someone who had a confirmed case of COVID-19.

So, she said, she waited, wondering: “When are we going to be able to test for this to see if it is in our community?”

About two weeks later, Milwaukee had its first case.

The city’s patient zero had been in contact with a person from a neighboring, predominately white and affluent suburb who had tested positive. Given how much commuting occurs in and out of Milwaukee, with some making a 180-mile round trip to Chicago, Kowalik said she knew it would only be a matter of time before the virus spread into the city.

A day later came the city’s second case, someone who contracted the virus while in Atlanta. Kowalik said she started questioning the rigidness of the testing guidelines. Why didn’t they include domestic travel?

By the fourth case, she said, “we determined community spread. … It happened so quickly.”

Within the span of a week, Milwaukee went from having one case to nearly 40. Most of the sick people were middle-aged, African American men. By week two, the city had over 350 cases. And now, there are more than 945 cases countywide, with the bulk in the city of Milwaukee, where the population is 39% black. People of all ages have contracted the virus and about half are African American.

The county’s online dashboard of coronavirus cases keeps up-to-date information on the racial breakdown of those who have tested positive. As of Thursday morning, 19 people had died of illness related to COVID-19 in Milwaukee County. All but four were black, according to the county medical examiner’s office. Records show that at least 11 of the deceased had diabetes, eight had hypertension and 15 had a mixture of chronic health conditions that included heart and lung disease.

Because of discrimination and generational income inequality, black households in the county earned only 50% as much as white ones in 2018, according to census statistics. Black people are far less likely to own homes than white people in Milwaukee and far more likely to rent, putting black renters at the mercy of landlords who can kick them out if they can’t pay during an economic crisis, at the same time as people are being told to stay home. And when it comes to health insurance, black people are more likely to be uninsured than their white counterparts.

African Americans have gravitated to jobs in sectors viewed as reliable paths to the middle class — health care, transportation, government, food supply — which are now deemed “essential,” rendering them unable to stay home. In places like New York City, the virus’ epicenter, black people are among the only ones still riding the subway.

“And let’s be clear, this is not because people want to live in those conditions,” said Gordon Francis Goodwin, who works for Government Alliance on Race and Equity, a national racial equity organization that worked with Milwaukee on its health and equity framework. “This is a matter of taking a look at how our history kept people from actually being fully included.”

Fred Royal, head of the Milwaukee branch of the NAACP, knows three people who have died from the virus, including 69-year-old Lenard Wells, a former Milwaukee police lieutenant and a mentor to others in the black community. Royal’s 38-year-old cousin died from the virus last week in Atlanta. His body was returned home Tuesday.

Royal is hearing that people aren’t necessarily being hospitalized but are being sent home instead and “told to self-medicate.”

“What is alarming about that,” he said, “is that a number of those individuals were sent home with symptoms and died before the confirmation of their test came back.”

Health Commissioner Kowalik said that there have been delays of up to two weeks in getting results back from some private labs, but nearly all of those who died have done so at hospitals or while in hospice. Still, Kowalik said she understood why some members in the black community distrusted the care they might receive in a hospital.

In January, a 25-year-old day care teacher named Tashonna Ward died after staff at Froedtert Hospital failed to check her vital signs. Federal officials examined 20 patient records and found seven patients, including Ward, didn’t receive proper care. The report didn’t reveal the race of those whose records it examined at the hospital, which predominantly serves black patients. Froedtert Hospital declined to speak to issues raised in the report, according to a February article from the Milwaukee Journal Sentinel, and it had not submitted any corrective actions to federal officials.

“What black folks are accustomed to in Milwaukee and anywhere in the country, really, is pain not being acknowledged and constant inequities that happen in health care delivery,” Kowalik said.

The health commissioner herself, a black woman who grew up in Milwaukee, said she’s all too familiar with the city’s enduring struggles with segregation and racism. Her mother is black and her father Polish, and she remembers the stories they shared about trying to buy a house as a young interracial couple in Sherman Park, a neighborhood once off-limits to blacks.

“My father couldn’t get a mortgage for the house. He had to go to the bank without my mom,” Kowalik said.

It is the same neighborhood where fury and frustration sparked protests that, at times, roiled into riots in 2016 when a Milwaukee police officer fatally shot Sylville Smith, a 23-year-old black man.

And it is the same neighborhood that has a concentration of poor health outcomes when you overlay a heat map of conditions, be it lead poisoning, infant mortality — and now, she said, COVID-19.

Knowing which communities are most impacted allows public health officials to tailor their messaging to overcome the distrust of black residents.

“We’ve been told so much misinformation over the years about the condition of our community,” Royal, of the NAACP, said. “I believe a lot of people don’t trust what the government says.”

Kowalik has met — virtually — with trusted and influential community leaders to discuss outreach efforts to ensure everyone is on the same page about the importance of staying home and keeping 6 feet away from others if they must go out.

Police and inspectors are responding to complaints received about “noncompliant” businesses forcing staff to come to work or not practicing social distancing in the workplace. Violators could face fines.

“Who are we getting these complaints from?” she asked. “Many people of color.”

Residents have been urged to call 211 if they need help with anything from finding something to eat or a place to stay. And the state has set up two voluntary isolation facilities for people with COVID-19 symptoms whose living situations are untenable, including a Super 8 motel in Milwaukee.

Despite the work being done in Milwaukee, experts like Linda Sprague Martinez, a community health researcher at Boston University’s School of Social Work, worry that the government is not paying close enough attention to race, and as the disease spreads, will do too little to blunt its toll.

“When COVID-19 passes and we see the losses … it will be deeply tied to the story of post-World War II policies that left communities marginalized,” Sprague said. “Its impact is going to be tied to our history and legacy of racial inequities. It’s going to be tied to the fact that we live in two very different worlds.”

Update, April 3, 2020: This story has been updated to reflect that Illinois and North Carolina are breaking coronavirus cases down by race.

This article originally appeared on ProPublica. You can read it here.

  • We paid college students about $5 a night to sleep at least 7 hours – and their grades quickly improved
    Photo credit: iStock via Getty Images Plus – Half of surveyed college students said they go to bed after 1 a.m., on average.
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    We paid college students about $5 a night to sleep at least 7 hours – and their grades quickly improved

    A university experiment tested whether small, immediate rewards could help students follow through on their intentions to get more rest.

    Paying college students about US$5 a night to sleep seven hours got them a quarter more nights of adequate sleep – and better grades.

    That is what we found in a study we published in July 2026.

    We gave more than 1,100 undergraduates at University of Pittsburgh a Fitbit – a wearable activity tracker that looks similar to a watch – and an app that sent bedtime reminders and morning feedback. We randomly chose 468 students and paid them about $5 for every night they slept at least seven hours, over the course of four weeks. We verified how much they slept using the device they wore.

    The students were about 19 years old, on average, and half of them were first-year students. Roughly 72% of them were women. About 55% were white, 28% Asian, 9% Black and 4% Hispanic.

    Our study shows that offering an immediate financial reward can help students meet a seven-hour sleep goal, and that those effects can persist up to a month beyond when the students are paid.

    Not just a student problem

    About one-third of American adults sleep less than seven hours a night, and a similar share say they wish they slept more. Among adolescents and young adults, roughly two-thirds routinely fall short of getting seven hours of sleep a night – the amount of shut-eye that health authorities recommend.

    One prominent sleep researcher has called sleep deprivation the most prevalent high-risk behavior.

    Short sleep is linked to obesity, diabetes, high blood pressure, heart disease, stroke and early death.

    Irregular sleep predicts mortality risk even more than sleep duration does. Sleep loss shows up in decision-making, even when it comes to issues like whether people vote.

    Students are running on empty

    Before we changed anything, the average student in our study slept 6.6 hours a night.

    Half were going to bed after 1 a.m. on average – a quarter after 2 a.m.

    Students got the recommended seven hours of sleep on a typical weeknight on only 43% of their nights, and more than 85% fell short at least once a week.

    They also did not know how much sleep they were getting. Two-thirds told us they usually slept seven hours – the trackers showed only about one-third of students slept that much on even three nights out of five.

    And 94% said their ideal night of sleep was longer than the one they were getting.

    What the money bought

    The 468 students we offered nightly payments reached seven hours of sleep on 26% more nights than 380 students who were not offered the money. That is a large shift for a group in which fewer than half were hitting the mark to begin with.

    Students receiving the monetary incentive slept 19 more minutes per school night, roughly the difference between closing the laptop at 11:40 p.m. or at midnight.

    Among students receiving the payment incentive, their GPA rose by about 0.08 points that semester – roughly a quarter of the gap between students who arrived with above-average and below-average high school grades.

    Once the payments stopped after four weeks, students who had received the money were still sleeping about eight minutes longer per night for the remaining three to four weeks of the study. The effect was smaller than during our study, but our findings suggest that some of the change in sleep habits persisted for up to a month after the end of the incentive.

    The effects of the intervention on sleep and GPA were largest among first-term freshmen, whose routines are not yet necessarily fixed.

    Rewards work – if they come right away

    Timing mattered too: Delivering the payment as a lump sum at the end of the semester, rather than every morning, produced only about two-thirds of the effect on sleep.

    The effects of the intervention on GPA faded over a couple of academic terms. Grades remained higher in the following semester, but two semesters later we could no longer detect an effect.

    Bedtime reminders and morning feedback on their own – with no money attached – had little effect. Students who received them slept only marginally more. The problem was not motivation: Nearly all said they wanted more sleep than they were getting. The challenge was following through on that intention night after night.

    Investing in sleep

    Our results show that universities should look at how the environment they create fosters or discourages good sleep habits.

    Late evening deadlines to submit assignments and early classes can both make it harder for students to get enough sleep. Changing some of these features costs little compared with many academic support programs, and it may be worth testing alongside other interventions aimed directly at students.

    Reminders and feedback might also work better if they change over time, rather than becoming familiar and easy to tune out.

    Very few universities or students treat sleep as part of an investment in education, or ask whether the schedules and incentives schools create make adequate sleep harder. Our results suggest they should.

    This article originally appeared on The Conversation. You can read it here.

  • Could you survive The Oregon Trail? An emergency medicine doctor offers tips on how to not die in the great outdoors
    You might not die of dysentery on the trail these days, but there is still plenty of danger outdoors. Different_Brian/iStock via Getty Images Plus
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    Could you survive The Oregon Trail? An emergency medicine doctor offers tips on how to not die in the great outdoors

    The old computer game’s hazards still hold lessons for modern hikers, even with smartphones, better medicine and sturdier equipment.

    If you grew up in the United States in the 1980s or ’90s, chances are you remember The Oregon Trail. For many like me, it was our first computer game and our first introduction to wilderness survival. We hunted buffalo, forded rivers, broke wagon wheels and, of course, learned about dysentery years before Google even existed, all while hoping our group would make it to Oregon City alive.

    Lately, the game has found a second life. Nostalgic social media posts, memes and updated versions of the game have introduced The Oregon Trail to a new generation while reminding millennials just how unforgiving that grainy computer screen journey could be.

    As a physician who specializes in emergency and wilderness medicine, I started thinking about how much of what the game taught me about surviving in the wilderness still applies today. After all, modern hikers and campers have access to tools the pioneers could never have imagined.

    Surprisingly, I’d argue that more lessons from The Oregon Trail hold up than you might think.

    Clean water is crucial

    The Oregon Trail game made dysentery famous for an entire generation. Fortunately, advances in sanitation, hand hygiene and antibiotics have made large outbreaks like those that wagon trains and military camps experienced much less common, at least in the United States.

    That doesn’t mean gastrointestinal illnesses have disappeared. Traveler’s diarrhea and cholera are still an important cause of illness around the world. Untreated water, poor hand hygiene and contaminated food can still derail any trip.

    Simple habits such as purifying drinking water, washing hands before meals and after using the bathroom, and practicing good camp hygiene remain some of the easiest ways to stay healthy outdoors.

    Steaming pot of water on small portable stove on top of a plank of wood in a forest
    Boiling is the most reliable way to purify your water. Veronika Lunina/iStock via Getty Images

    Water purification is important with wilderness travel in the United States and in many areas of the world. There are many easy and cost-effective ways to purify water, such as boiling, filtration and treating with chemical disinfectants. Each method has its benefits and downsides.

    Boiling is often the most accessible method. While it can kill bacteria, viruses and parasites, it will not remove water contaminants such as heavy metals, including lead and arsenic, or industrial contamination such as pesticides. Consider boiling your water for at least one to three minutes, depending on your altitude, to purify it. Water filtration is an easy option for backpackers but is less effective at removing viruses.

    If you’re unable to boil your water, another way to ensure water safety is to filter it, then use another method to disinfect it.

    Respect all waterways

    You may no longer have to ford the river with oxen, but rivers, lakes and other bodies of water present unique hazards that outdoor adventure enthusiasts can overlook.

    Moving water can be more dangerous than people realize. Even the best swimmers can drown in rip currents.

    Cross bodies of water only when absolutely necessary. Avoid any water crossings after recent rainfall, as the water level often rises and the current can be faster and stronger. Submerged objects – rocks, fallen trees and other debris – as well as changing weather, flash flooding and strong currents can make crossing more dangerous.

    If possible, use a Coast Guard-approved life jacket when you’re crossing water or on a boat.

    Be ready to go the distance

    It’s not just a broken wagon axle that can send a trip sideways. One thing The Oregon Trail captured well is how distance changes everything. A sprained ankle in a city usually means an inconvenient trip home or to the doctor, but a sprained ankle 5 miles from the trailhead may mean that someone will need to carry you. The same is true for other common wilderness concerns, such as dehydration, heat illness, infections or even blisters.

    Preparation is about packing a first aid kit and thinking ahead. Ask yourself what you would do if your hike took twice as long as expected or if you unexpectedly had to spend the night outside. Research your route and carry more food and water than you think you’ll need. Check the weather and be prepared for it to change, with extra clothing and options for rain.

    Group of hikers walking through forest, away from camera
    It’s dangerous to go alone. FG Trade/E+ via Getty Images

    No one tackled the Oregon Trail alone because it meant you would not survive. There is a lesson here in solo travel and solo mountaineering.

    Traveling alone means that a minor injury such as a sprained ankle could mean crawling to the trailhead to call for help or waiting until you are identified as missing. If you cannot find someone to travel with you, provide an itinerary and travel location to a trusted person. Make sure they know when you should be returning and plan to check in. If you do not return as expected, they can call for help.

    Respect the wildlife

    Large animals still pose a threat across the country. While there may be fewer bison than previously seen on the Oregon Trail, animals in nature deserve respect.

    No selfie is worth being attacked by a brown bear. If you see a dangerous wild animal, avoid approaching and immediately leave the area.

    Venomous snakes are present throughout much of the United States and continue to cause significant injury and death around the world. If someone is bitten, please don’t try to cut the wound or suck out the venom. Instead, keep the person calm, minimize unnecessary movement, and focus on getting them to professional medical care. Antivenom is available in many major hospitals in the United States.

    Even smaller and more docile animals such as deer and squirrels should not be fed. It is dangerous for an animal to get used to receiving food from humans. Additionally, animals carry diseases, such as rabies and leptospirosis, that can be fatal to people.

    Don’t attempt to get close to any animals, no matter how calm or asleep the animal appears to be.

    Technology is a backup, not a plan

    One of the biggest differences between today’s outdoor adventures and those of the Oregon Trail is the ability to communicate.

    Cellphones, GPS apps and emergency beacons have made it possible to call for help from places that were once completely isolated. However, while those devices are incredibly valuable, they shouldn’t encourage you to take bigger risks, as help may be far away, slow to arrive, and injuries in the wilderness can be fatal.

    Travelers can use a smartphone with GPS capacity to avoid getting lost, but downloading any needed maps for offline use can help prevent lack of service from derailing your trip.

    Additionally, an unlocked smartphone that isn’t restricted to one carrier is a great way to store and communicate critical data, such as travel plans and copies of your medical history.

    Person leaning over map spread over a rock beside a bike, plains stretching into the background
    Having an offline map is critical when going somewhere remote. Grant Ordelheide/Aurora Photos/Cavan via Getty Images

    Every environment has its own hazards

    The Oregon Trail travelers worried about river crossings, disease and harsh weather. Today’s hikers face different challenges depending on where they are.

    Desert hikers may struggle with extreme heat and dehydration. Mountain travelers face rapidly changing weather, lightning and high altitude. And coastal explorers can face problems such as riptides, waves, cliffs and unexpected rocky surfaces.

    Altitude illness is often unpredictable and can sneak up on you. Most people experience acute mountain sickness within 24 hours of ascent, developing symptoms such as headache, fatigue, nausea or problems with sleep. Any confusion, difficulty walking, shortness of breath or coughing up significant phlegm should prompt an immediate descent.

    There are commonly used prescription medications to help prevent and treat altitude illness. The mountain will always be waiting for your next attempt.

    Some lessons survive every software update

    Part of what made The Oregon Trail game memorable is that every decision mattered. Success often depended less on luck than on planning ahead, and that lesson still applies.

    When people ask me what one emergency medicine skill everyone should know before heading outdoors, my answer is usually preparation. Thoughtful planning prevents far more emergencies than any single piece of equipment.

    For people who spend a lot of time outdoors, I also recommend taking a wilderness first aid course. These courses teach practical skills to provide medical care in a wilderness environment.

    Nature is no less powerful or unforgiving than it was on the Oregon Trail, and treating it with respect is essential. Combining advances in modern medicine with thoughtful preparation helps stack the odds in your favor so that, just as every Oregon Trail player hoped, everyone in the party makes it to the end.

    This article originally appeared on The Conversation. You can read it here.
  • Your cells keep a record of every workout you’ve ever done – and those gains persist even after a break from exercise
    Photo credit: Williams+Hirakawa/The Image Bank via Getty Images – Your body retains the benefits of exercise even when you need to hit pause.
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    Your cells keep a record of every workout you’ve ever done – and those gains persist even after a break from exercise

    New research suggests muscle and liver cells retain a memory of exercise, offering hope when injury or life interrupts a workout routine.

    Have you ever taken months off training – maybe due to an injury, a new baby or crushing work deadlines – and come back convinced you were starting from zero?

    Research from our team has some good news: At the cellular level, you probably weren’t.

    We found that muscle and liver cells store memories from every training session in ways that may help improve endurance, control blood sugar levels and even slow weight regain after inactivity.

    Use it or lose it? Maybe not

    For most of the past century, long before fad diets and fancy workout trends took off, exercise was considered one of the most effective lifestyle changes to lower the risk of heart disease, Type 2 diabetes, several cancers and early death for people of all ages. But people typically understood exercise as something whose beneficial effects fade away over time: You use it or lose it.

    When you stop training, your maximum oxygen uptake, muscle gains and insulin sensitivity drift back to where they started, often within weeks. Physical activity guidelines are built on this fact, which is why they emphasize consistency above all else.

    Consistency, however, is a luxury that roughly 3 in 4 American adults aren’t able to enjoy. People can experience injuries, illness, pregnancy or jobs that limit their time for or ability to exercise. If adaptation really resets, every time you step into the gym would be as if you’ve never been there before. But that scenario doesn’t match what coaches and returning athletes typically describe: In practice, people who have trained before can get fit again faster than those who haven’t undergone similar training.

    In recent years, however, scientists have started challenging the concept of “use it or lose it.” New research hints that your cells might keep a record of your training history so all of your gains are not completely lost.

    More than muscle

    We are exercise physiologists who study how cells remember exercise. Our lab and others have shown that the body is able to store a form of exercise memory across different organs.

    To study how this exercise memory works, our team of researchers use an ON-OFF-ON exercise training protocol in mice, which involves an initial four- to eight-week training period, followed by detraining – a period of no exercise – and a second training bout. This method allows us to examine how cells form a memory of exercise, maintain a record of exercise through detraining, and recall memories of prior training when exposed again to exercise.

    Using this strategy, our team found that skeletal muscle memory accelerates muscle growth. Compared to mice with no training history, mice who retrained grew bigger muscles, and the individual muscle fibers inside those muscles grew too. Larger muscle fibers meant that the working cells were themselves getting bigger, rather than the surrounding tissue.

    Looking more closely at these muscle cells, we found that retrained muscle is better at matching energy production to demand – meaning, the muscles were better at drawing from energy stores when it’s needed most – and this ability persists without further exercise. This memory held even when the mice ate a high-fat diet, suggesting that prior training can still offer benefits even when diet is working against those gains.

    Muscle isn’t the only body part that learns from exercise. Working muscle needs fuel, and the liver supplies it during and after training sessions.

    My colleagues and I found that liver cells also store exercise memory and uses it to feed muscle more efficiently. In both mice and people who trained, stopped, then trained again, their livers released higher levels of a family of enzymes called carboxylesterases. These enzymes chop up lipids circulating in the blood, delivering fat in a form that muscle can take up and burn as it grows.

    A record that outlives you

    Recorded cellular memories of exercise may even be passed down to future generations.

    In mice, we found that three to four weeks of maternal and paternal endurance exercise can have a lasting effect on their offspring. Compared to offspring born to sedentary parents, parental exercise granted protection against poor blood sugar levels and excess weight gain for an entire year after birth.

    Researchers have hypothesized numerous ways that prenatal exercise may affect offspring. For example, maternal exercise might allow offspring to spend more time developing in the womb or lead parents to producer higher quality milk.

    But there remains much to be discovered on how parents influence the health of their children and whether their lifestyle could provide a fitness advantage across generations.

    Every cell remembers

    Biology has traditionally granted memory to a short list of cells. Neurons store memory in the connections between them. Immune cells store memory so they can recognize pathogens faster and more strongly the next time they encounter them.

    Researchers previously considered all other cells to be memoryless; a cell responds to a signal, then returns to baseline without keeping a record of that interaction. But that assumption is now coming apart.

    Skin stem cells can keep a record of inflammation, allowing them to heal a new wound faster months later. Human fat cells keep a record of obesity that persists even after substantial weight loss, which may account for why you gain weight faster when switching back to a high-calorie diet – the so-called yo-yo effect.

    We propose that every cell in the body remembers exercise, regardless of how little or how much someone trains. The question is how long these records are stored and whether researchers could prolong or expand each cell’s storage capacity. Better understanding of how cells learn and remember exercise, where they store memories and how those memories are preserved could help improve exercise guidelines for those who cannot exercise for prolonged or consistent periods of time.

    To be clear, none of these findings are evidence for skipping the gym; nothing in our data suggests the effects of past training can substitute for present training. But there is hope that the work you put into getting in shape isn’t completely lost over time.

    Somewhere, deep in your cells, there is a record waiting to be replayed the next time you lace up your running shoes, pick up a pair of dumbbells or want to fulfill a New Year’s resolution.

    This article originally appeared on The Conversation. You can read it here.

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