Category: Exercise

Categories : Cardiovascular Disease ExerciseTags :

Bursts of Activity could Cut Heart Risk in Women

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An average of four minutes of incidental vigorous physical activity a day could almost halve the risk of major cardiovascular events, such as heart attacks, for middle-aged women who do not engage in structured exercise, according to new research from the University of Sydney, published in the British Journal of Sports Medicine.

“We found that a minimum of 1.5 minutes to an average of 4 minutes of daily vigorous physical activity, completed in short bursts lasting up to 1 minute, were associated with improved cardiovascular health outcomes in middle-aged women who do no structured exercise,” said lead author Professor Emmanuel Stamatakis, Director of the Mackenzie Wearable Hub at the Charles Perkins Centre and the Faculty of Medicine and Health.

High-intensity physical activity that forms part of a daily routine is known as “vigorous intermittent lifestyle physical activity” (VILPA). Physical activity is incidental such as walking to the shops, vs exercise, which is structured, eg going to the gym. Longer sessions of VILPA are linked to significantly lower cardiovascular disease risk.

The researchers say that, given fewer than 20% of middle-aged or older adults engage in regular structured exercise, engaging in VILPA could be a good alternative.

“Making short bursts of vigorous physical activity a lifestyle habit could be a promising option for women who are not keen on structured exercise or are unable to do it for any reason. As a starting point, it could be as simple as incorporating throughout the day a few minutes of activities like stair climbing, carrying shopping, uphill walking, playing tag with a child or pet, or either uphill or power walking,” said Professor Stamatakis.

The study drew on UK Biobank data from 22 368 participants (13 018 women) aged 40–79 who reported they did not engage in regular structured exercise and who wore physical activity trackers for almost 24 hours a day for 7 days.

Cardiovascular health was monitored through hospital and mortality records, tracking major adverse cardiovascular events (MACE), such as heart attack, stroke, and heart failure, until November 2022.

After adjusting for factors such as lifestyle, socioeconomic position, cardiovascular health, co-existing conditions, and ethnicity, the researchers found that the more VILPA women did, the lower their risk of a major cardiovascular event.

Women who averaged 3.4 minutes of VILPA daily were 45 percent less likely to experience a major cardiovascular event. They were also 51% less likely to have a heart attack and 67 percent less likely to develop heart failure than women who did no VILPA.

Even when amounts of daily VILPA were lower than 3.4 minutes they were still linked to lower cardiovascular event risk. A minimum of 1.2 to 1.6 minutes of VILPA per day was associated with a 30 percent lower risk of total major cardiovascular events, a 33 percent lower risk of heart attack, and a 40 percent lower risk of heart failure.

However, men reaped fewer benefits from tiny bursts of VILPA. Those who averaged 5.6 minutes daily were only 16% less likely to experience a major cardiovascular event compared with men who did none. A minimum of 2.3 minutes per day was associated with only an 11% risk reduction.

Professor Stamatakis said more testing was needed to understand how VILPA may improve cardiovascular health.

“To date, it hasn’t been clear whether short bursts of VILPA lower the risk of specific types of cardiovascular events, like heart attack or stroke. We aimed to identify minimum daily thresholds and feasible amounts for testing in community programs and future trials,” he said.

“Importantly, the beneficial associations we observed were in women who committed to short bursts of VILPA almost daily. This highlights the importance of habit formation, which is not always easy. VILPA should not be seen as a quick fix – there are no magic bullets for health. But our results show that even a little bit higher intensity activity can help and might be just the thing to help people develop a regular physical activity – or even exercise – habit,” he said.

For the purposes of this story, physical activity is incidental, eg carrying shopping or briefly power walking, and exercise is structured, eg going to the gym or playing sport.

Source: University of Sydney

Categories : ExerciseTags :

Home and Neighbourhood Environments Impact Sedentary Behaviour in Teens Globally

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The World Health Organization recommends no more than two to three hours per day of sedentary time for youth. However, adolescents worldwide are spending an average of 8 to 10 hours per day engaging in sedentary activities such as watching television, using electronic devices, playing video games and riding in motorised vehicles, according to a 15-country study published in the International Journal of Behavioral Nutrition and Physical Activity.

The most notable finding of the study, led by principal investigator James F. Sallis, PhD, distinguished professor at University of California San Diego, and colleagues from 14 countries, found that simply having a personal social media account was linked with higher total sedentary time in both males and females. Social media was also related to more self-reported screen time.

“Although there is great concern about negative effects of social media on youth mental health, this study documents a pathway for social media to harm physical health as well,” said Sallis, who is also a professorial fellow at the Australian Catholic University.

“These findings are concerning, as excessive sedentary behavior has been linked to a range of health problems, including obesity, diabetes and mental health issues.”

Researchers analysed accelerometer data from 3,982 adolescents aged 11 to 19 and survey measures of sedentary behaviour from 6,02 participants in the International Physical Activity and the Environment Network (IPEN) Adolescent Study, which covered 15 geographically and culturally diverse countries across six continents.

The number of electronic devices within a home, how many adolescents had their own social media accounts and neighbourhood walkability were significantly different across countries.

For example, adolescents from India had an average of 1.2 electronic devices in the bedroom and 0.5 personal electronic devices, while the average number of such devices in Denmark was 4.2 and 2.3, respectively. In India and Bangladesh, fewer than 30% of adolescents reported having their own social media account, compared to higher socio-economic status countries where it was over 90%.

Parents reporting on walkability identified Australia as having high access to parks, while Nigerian parents reported no access, and parents in Bangladesh and India reported poor access. Traffic was a concern among parents in Brazil, Malaysia, Bangladesh, India, and Israel, and concerns about crime were high in the first three countries.

Adolescents who reported less recreational screen time lived in walkable neighbourhoods and had better perceptions of safety from traffic and crime than others. Girls who lived in neighbourhoods designed to support physical activity were less likely to be sedentary.

Despite differences in culture, built environments and extent of sedentary time, patterns of association were generally similar across countries, said the study’s lead author Ranjit Mohan Anjana, MD, PhD, of Dr Mohan’s Diabetes Specialties Centre and Madras Diabetes Research Foundation in India.

“Together, parents, policymakers and technology companies can work together to reduce access to screens, limit social media engagement and promote more physical activity, thus helping adolescents develop healthier habits and reduce their risk of chronic diseases,” said Anjana.

The study’s findings have significant implications for public health policy and highlight the need for further research into the causes and consequences of sedentary behaviour among teenagers.

Source: University of California – San Diego

Categories : Ageing ExerciseTags :

Many Could Easily Add Five Years to Their Lifespan

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If everyone was as active as the top 25% of the population, individuals over the age of 40 could add five years to their life, according to a new study led by Griffith University researchers. 

Physical activity has long been known to be good for health, however estimates have varied regarding how much benefit could be gained from a defined amount of activity, both for individuals and for populations. 

This latest study, published in the British Journal of Sports Medicine, used US-based accelerometer data to gain an accurate view of a population’s physical activity levels instead of relying on survey responses as per other studies, and found the benefits were around twice as strong as previous estimates.  

It found the most active quarter of people in the community had a 73% lower risk of death than their least active counterparts. For that least active quartile, a single one-hour walk could potentially return a benefit of around six additional hours of life.  

Lead researcher Professor Lennert Veerman said this cohort had the greatest potential for health gains.  

“If you’re already very active or in that top quartile, an extra hour’s walk may not make much difference as you’ve, in a sense, already ‘maxed out’ your benefit,” he said.   

“If the least active quartile of the population over age 40 were to increase their activity level to that of the most active quartile however, they might live, on average, about 11 years longer.

“This is not an unreasonable prospect, as 25 per cent of the population is already doing it.  It can be any type of exercise but would roughly be the equivalent of just under three hours of walking per day.” 

The research team suggested low levels of physical activity could even rival the negative effects of smoking, with other research finding each cigarette could take 11 minutes from a smoker’s life.  

By extension, a more active lifestyle could also offer protective effects against heart disease, stroke, certain cancers and other chronic illnesses, with the study’s findings highlighting a need for national physical activity guidelines to be revisited using these methods.  

Dr Veerman said physical activity had been vastly underestimated in its capacity to improve health outcomes, suggesting even modest increases in movement could lead to significant life-extension benefits.  

“If there’s something you could do to more than halve your risk of death, physical activity is enormously powerful,” he said.  

“If we could increase investment in promoting physical activity and creating living environments that promote it such as walkable or cyclable neighbourhoods and convenient, affordable public transport systems, we could not only increase longevity but also reduce pressure on our health systems and the environment.”  

Source: Griffith University

Categories : Exercise NeurologyTags :

Workouts – or Disturbed Sleep – Impact Brain Activity Weeks Later

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In a rare, longitudinal study, researchers from Aalto University and the University of Oulu tracked one person’s brain and behavioural activity for five months using brain scans and data from wearable devices and smartphones. The results appear in PLOS Biology.

“We wanted to go beyond isolated events,” says research leader (and study participant) Ana Triana. “Our behaviour and mental states are constantly shaped by our environment and experiences. Yet, we know little about the response of brain functional connectivity to environmental, physiological, and behavioural changes on different timescales, from days to months.”

The study found that the brain does not respond to daily life in immediate, isolated bursts. Instead, brain activity evolves in response to sleep patterns, physical activity, mood, and respiration rate over many days. This suggests that even a workout or a restless night from last week could still affect the brain – and therefore attention, cognition and memory – well into next week.

The research also revealed a strong link between heart rate variability – a measure of the heart’s adaptability – and brain connectivity, particularly during rest. This suggests that impacts on the body’s relaxation response, like stress management techniques, could shape brain wiring even when not actively concentrating on a task. Physical activity was also found to positively influence the way brain regions interact, potentially impacting memory and cognitive flexibility. Even subtle shifts in mood and heart rate left lasting imprints for up to 15 days.

Study goes beyond a snapshot

The research is unusual in that few brain studies involve detailed monitoring over days and weeks. “The use of wearable technology was crucial,” says Triana. “Brain scans are useful tools, but a snapshot of someone lying still for half an hour can only show so much. Our brains do not work in isolation.”

Triana was herself the subject of the research, monitored as she went about her daily life. Her unique role as both lead author and study participant added complexity, but also brought firsthand insights into how best to maintain research integrity over several months of personalised data collection.  Data from the devices and twice-weekly brain scans were complemented by qualitative data from mood surveys. 

The researchers identified two distinct response patterns: a short-term wave lasting under seven days and a long-term wave up to 15 days. The former reflects rapid adaptations, like how focus is impacted by poor sleep, but it recovers quickly. The long wave suggests more gradual, lasting effects, particularly in areas tied to attention and memory. 

Single-subject studies offer opportunities for improving mental health care 

The researchers hope their innovative approach will inspire future studies that combine brain data with everyday life to help personalise mental health treatment. 

“We must bring data from daily life into the lab to see the full picture of how our habits shape the brain, but surveys can be tiring and inaccurate,” says study co-author, neuroscientist and physician Dr Nick Hayward. “Combining concurrent physiology with repeated brain scans in one person is crucial. Our approach gives context to neuroscience and delivers very fine detail to our understanding of the brain.”

The study is also a proof-of-concept for patient research. Tracking brain changes in real time could help detect neurological disorders early, especially mental health conditions where subtle signs might be missed.

“Linking brain activity with physiological and environmental data could revolutionise personalised healthcare, opening doors for earlier interventions and better outcomes,” says Triana.

Source: Aalto University

Categories : Cardiovascular Disease ExerciseTags :

Even Moderate Amounts of Exercise May Reduce Risk for Atrial Fibrillation

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Adding an extra hour every week of physical activity may lower the chance of developing the most common type of irregular heartbeat (arryhthmia) by 11%, a new study shows.

Led by researchers at NYU Langone Health, the investigation focused on atrial fibrillation. While past studies have linked exercise to reduced risk of this type of arrhythmia, nearly all of these analyses have relied on participants’ often inaccurate estimates of their own activity levels, the authors say.

To avert this flaw, the current study team used data recorded from the fitness tracker Fitbit to objectively measure physical activity in more than 6000 men and women across the United States. The results showed that those with higher amounts of weekly physical activity were less likely to develop atrial fibrillation. Notably, the researchers say, even modest amounts of moderate to vigorous exercise, which can range from taking a brisk walk or cleaning the house to swimming laps or jogging, were associated with reduced risk.

Specifically, study participants who averaged between 2.5 and 5 hours per week, the minimum amount recommended by the American Heart Association, showed a 60% lower risk of developing atrial fibrillation. Those who averaged greater than 5 hours had a slightly greater (65%) reduction.

“Our findings make clear that you do not need to start running marathons to help prevent atrial fibrillation and other forms of heart disease,” said preventive cardiologist Sean P. Heffron, MD, the study senior author. “Just keeping moderately active can, over time, add up to major benefits for maintaining a healthy heart,” added Dr Heffron, an assistant professor in the Department of Medicine at NYU Grossman School of Medicine.

Dr. Heffron notes that in the sole earlier study that used activity monitors to investigate atrial fibrillation, researchers provided Fitbit-style monitors to the participants and tracked them for only a week, an approach that may not have accurately captured their normal workout habits. The new investigation, which the authors say is the largest of its kind to date, assessed participants for a full year and included only those who already owned the devices.

A report on the findings will be presented at the annual meeting of the American Heart Association on November 16.

From data collected as part of the All of Us Research Program, the authors of the current study assessed physical activity in the subset (6086 people) who used a Fitbit device and permitted their Fitbit and electronic health records to be linked to their All of Us data. The team tracked activity information for a year as a baseline and then followed up for another five years to identify those who were diagnosed with atrial fibrillation. The researchers also took into account factors known to contribute to the condition, such as age, sex, and a history of high blood pressure.

“These results highlight the value of Fitbits and similar monitors in medical research,” said study lead author Souptik Barua, PhD, an assistant professor in the Department of Medicine at NYU Grossman School of Medicine. “By offering an objective way to measure exercise for years at a time, these tools can provide deeper insight into how different patterns of activity can impact health.”

For example, says Dr Barua, the research team next plans to explore whether working out in the morning or at night may have different effects on heart health.

He cautions that since many Fitbit owners in the study were college-educated White women, the investigation assessed a less-diverse group than that of the overall All of Us population. The program is now providing free devices to participants in underrepresented communities for future investigations.

Dr. Barua also cautions that the study was not designed to tell whether exercise alone directly reduced the risk of atrial fibrillation, nor to detect how that might come about or what other factors, such as income or educational status, might be in play in the reduced risk. However, the association between exercise “doses” and the development of the condition in the study participants was strong.

Source: NYU Langone Health / NYU Grossman School of Medicine

Categories : Cardiovascular Disease ExerciseTags :

An Extra Five Minutes of Exercise a Day could Reduce Blood Pressure

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New research suggests that adding a small amount of daily physical activity, such as uphill walking or stair-climbing, may help to lower blood pressure. The findings were published in Circulation. 

Just five minutes of activity a day was estimated to potentially reduce blood pressure, while replacing sedentary behaviours with 20–27 minutes of exercise per day, including uphill walking, stair-climbing, running and cycling, was also estimated to lead to a clinically meaningful reduction in blood pressure. The study was done by experts from the ProPASS (Prospective Physical Activity, Sitting and Sleep) Consortium, an international academic collaboration led by the University of Sydney and University College London (UCL)

Joint senior author Professor Emmanuel Stamatakis, Director of the ProPASS Consortium said: “High blood pressure is one of the biggest health issues globally, but unlike some major causes of cardiovascular mortality there may be relatively accessible ways to tackle the problem in addition to medication.”

“The finding that doing as little as five extra minutes of exercise per day could be associated with measurably lower blood pressure readings emphasises how powerful short bouts of higher intensity movement could be for blood pressure management.”

The research team analysed health data from 14 761 volunteers in five countries to see how replacing one type of movement behaviour with another across the day is associated with blood pressure.

Each participant used a wearable accelerometer device on their thigh to measure their activity and blood pressure throughout the day and night. 

Daily activity was split into six categories: sleep, sedentary behaviour (such as sitting), slow walking, fast walking, standing, and more vigorous exercise such as running, cycling or stair climbing.

The team modelled statistically what would happen if an individual changed various amounts of one behaviour for another in order to estimate the effect on blood pressure for each scenario and found that replacing sedentary behaviour with 20-27 minutes of exercise per day could potentially reduce cardiovascular disease by up to 28 percent at a population level.

First author Dr Jo Blodgett from UCL said: “Our findings suggest that, for most people, exercise is key to reducing blood pressure, rather than less strenuous forms of movement such as walking.

“The good news is that whatever your physical ability, it doesn’t take long to have a positive effect on blood pressure. What’s unique about our exercise variable is that it includes all exercise-like activities, from running for a bus or a short cycling errand, many of which can be integrated into daily routines.

“For those who don’t do a lot of exercise, walking did still have some positive benefits for blood pressure. But if you want to change your blood pressure, putting more demand on the cardiovascular system through exercise will have the greatest effect.”

Professor Mark Hamer, joint senior author of the study and ProPASS Deputy Director from UCL, said: “Our findings show how powerful research platforms like the ProPASS consortium are for identifying relatively subtle patterns of exercise, sleep, and sedentary behaviour, that have  significant clinical and public health importance.”

Source: University of Sydney

Categories : Exercise GastrointestinalTags :

Study Suggests that High-intensity Exercise Suppresses Appetite – Especially in Women

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A vigorous workout does more to suppress hunger levels in healthy adults than does moderate exercise, and females may be especially susceptible to this response, according to a small study published in the Journal of the Endocrine Society.

The study examines the effects of exercise intensity on ghrelin levels and appetite between men and women. Ghrelin is known as the “hunger hormone” and is associated with perceptions of hunger.

“We found that high intensity exercise suppressed ghrelin levels more than moderate intensity exercise,” said lead author Kara Anderson, PhD, of the University of Virginia. “In addition, we found that individuals felt ‘less hungry’ after high intensity exercise compared to moderate intensity exercise.”

Ghrelin circulates in acylated (AG) and deacylated (DAG) forms, which are known to affect appetite. Data on the impact of exercise intensity on AG and DAG levels, and their effects on appetite, is sparse and primarily limited to males, the study noted.

To address this shortfall, the study examined eight males and six females. Participants fasted overnight and then completed exercises of varying intensity levels, determined by measurements of blood lactate, followed by self-reported measurements of appetite.

Females had higher levels of total ghrelin at baseline compared with males, the study noted. But only females demonstrated “significantly reduced AG” following the intense exercise, according to the findings.

“We found that moderate intensity either did not change ghrelin levels or led to a net increase,” the study noted. These findings suggest that exercise above the lactate threshold “may be necessary to elicit a suppression in ghrelin.”

Researchers also acknowledged that more work is needed to determine the extent to which the effects of exercise differ by sex. Ghrelin has been shown to have wide-ranging biological effects in areas including energy balance, appetite, glucose homeostasis, immune function, sleep, and memory.

“Exercise should be thought of as a ‘drug,’ where the ‘dose’ should be customised based on an individual’s personal goals,” Anderson said. “Our research suggests that high-intensity exercise may be important for appetite suppression, which can be particularly useful as part of a weight loss program.”

Source: The Endocrine Society

Categories : Exercise PaediatricsTags :

Outdoor Play Helps Protect Toddlers against Later Childhood Obesity

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New research published in Acta Paediatrica suggests that children who engage in outdoor play during their preschool years have a lower risk of developing obesity later in childhood.

The study included children born in Japan during two weeks in January and July 2001. Of 53 575 children born, 42 812 had data on outdoor play habits at age 2.5 years. In a survey, parents were asked, “Where do your children usually play (excluding home residences and daycare centres attended)?” Available options for answers included “in my garden or on the grounds of my apartment complex,” “in parks,” “in natural areas such as fields, forests, and beaches,” “on the street,” “in shrines and temples,” “in playgrounds in department stores and supermarkets,” “other,” and “don’t play anywhere but inside my home.” If one or more of the first five items were chosen, a child was considered to have exposure to outdoor play—this was the case for 91% of the children.

In follow-up surveys when the children were seven years old, 31 743 of 42 812 (74%) children had height and weight data, with 10% classified as overweight or obese.

Compared with children without exposure to outdoor play, children with outdoor play habits had 15% lower odds of being overweight or obese, after adjusting for other influencing factors.

“We suggest that parents and caregivers encourage outdoor play habits in their children at an early age, as this may help prevent obesity later in life,” said corresponding author Takahiro Tsuge, MPH, of Kurashiki Medical Center.

Source: Wiley

Categories : Cancer ExerciseTags :

Aerobic Exercise may Help Prevent the Brain Fog from Chemotherapy

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Clinical trial reveals improved self-reported cognitive function in women with breast cancer who started an exercise program when initiating chemotherapy.

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Many women who receive chemotherapy experience a decreased ability to remember, concentrate, and/or think – commonly referred to as “chemo-brain” or “brain fog” – both short- and long-term. In a recent clinical trial of women initiating chemotherapy for breast cancer, those who simultaneously started an aerobic exercise program self-reported greater improvements in cognitive function and quality of life compared with those receiving standard care. The findings are published by Wiley online in CANCER, a peer-reviewed journal of the American Cancer Society.

The study, called the Aerobic exercise and CogniTIVe functioning in women with breAsT cancEr (ACTIVATE) trial, included 57 Canadian women in Ottawa and Vancouver who were diagnosed with stage I–III breast cancer and beginning chemotherapy. All women participated in 12–24 weeks of aerobic exercise: 28 started this exercise when initiating chemotherapy and 29 started after chemotherapy completion. Cognitive function assessments were conducted before chemotherapy initiation and after chemotherapy completion (therefore, before the latter group started the exercise program).

Women who participated in the aerobic exercise program during chemotherapy self-reported better cognitive functioning and felt their mental abilities improved compared with those who received standard care without exercise. Neuropsychological testing – a performance-based method used to measure a range of mental functions – revealed similar cognitive performance in the two groups after chemotherapy completion, however.

“Our findings strengthen the case for making exercise assessment, recommendation, and referral a routine part of cancer care; this may help empower women living with and beyond cancer to actively manage both their physical and mental health during and after treatment,” said lead author Jennifer Brunet, PhD, of the University of Ottawa.

Dr Brunet noted that many women undergoing chemotherapy for breast cancer remain insufficiently active, and there are limited exercise programs tailored to their needs. “To address this, we advocate for collaboration across various sectors – academic, healthcare, fitness, and community – to develop exercise programs specifically designed for women with breast cancer,” she said. “These programs should be easy to adopt and implement widely, helping to make the benefits of exercise more accessible to all women facing the challenges of cancer treatment and recovery.”

Source: Wiley

Categories : Exercise Skeletal SystemTags :

The Arms and Torso of Human Males Evolved to Throw a Punch

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In the animal kingdom, males develop specialised weapons such as deer antlers for competition when winning a fight is critical. Humans do too, according to new research from the University of Utah. Males’ upper bodies are built for more powerful punches than females’, says the study, published in the Journal of Experimental Biology, suggesting that fighting may have long been a part of our evolutionary history.

“In mammals in general,” says professor David Carrier of the School of Biological Sciences, “the difference between males and females is often greatest in the structures that are used as weapons.”

Assembling evidence

For years, Carrier has been exploring the hypothesis that generations of interpersonal male-male aggression long in the past have shaped structures in human bodies to specialise for success in fighting. Past work has shown that the proportions of the hand aren’t just for manual dexterity- they also protect the hand when it’s formed into a fist. Other studies looked at the strength of the bones of the face (as a likely target of a punch) and how our heels, planted on the ground, can confer additional upper body power.

“One of the predictions that comes out of those,” Carrier says, “is if we are specialised for punching, you might expect males to be particularly strong in the muscles that are associated with throwing a punch.”

Jeremy Morris, then a doctoral student and now an assistant professor at Wofford College, designed an experiment with Carrier, doctoral student Jenna Link and associate professor James C. Martin to explore the sexual dimorphism, or physical differences between men and women, of punching strength. It’s already known that males’ upper bodies, on average, have 75% more muscle mass and 90% more strength than females’. But it’s not known why.

“The general approach to understanding why sexual dimorphism evolves,” Morris says, “is to measure the actual differences in the muscles or the skeletons of males and females of a given species, and then look at the behaviours that might be driving those differences.”

Cranking through a punch

To avoid potential hand injury from a using punching bag, the researchers instead rigged up a hand crank that would mimic the motions of a punch. They also measured participants’ strength in pulling a line forward over their head, akin to the motion of throwing a spear. This tested an alternative hypothesis that males’ upper body strength may have developed for the purpose of throwing or spear hunting.

Twenty men and 19 women participated. “We had them fill out an activity questionnaire,” Morris says, “and they had to score in the ‘active’ range. So, we weren’t getting couch potatoes, we were getting people that were very fit and active.”

But even with roughly uniform levels of fitness, the males’ average power during a punching motion was 162% greater than females’, with the least-powerful man still stronger than the most powerful woman. Such a distinction between genders, Carrier says, develops with time and with purpose.

“It evolves slowly,” he says, “and this is a dramatic example of sexual dimorphism that’s consistent with males becoming more specialised for fighting, and males fighting in a particular way, which is throwing punches.”

They didn’t find the same magnitude of difference in overhead pulling strength, lending additional weight to the conclusion that males’ upper body strength is specialised for punching rather than throwing weapons.

Breaking a legacy of violence

It’s an uncomfortable thought to consider that men may be designed for fighting. That doesn’t mean, however, that men today are destined to live their ancestor’s violent lives.

“Human nature is also characterized by avoiding violence and finding ways to be cooperative and work together, to have empathy, to care for each other, right?” Carrier says. “There are two sides to who we are as a species. If our goal is to minimise all forms of violence in the future, then understanding our tendencies and what our nature really is, is going to help.”

Source: University of Utah