Tag: aerobic exercise

Early Fitness Linked to Healthier Arteries

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People with good physical fitness in their 30s and 50s have more elastic arteries later in life. This is shown in a new study from Karolinska Institutet, published in the journal Scientific Reports. The association remains regardless of cholesterol levels and other risk factors.

Cardiovascular disease is the leading cause of death worldwide. One early sign of increased risk is stiffening of the arteries, which can contribute to heart attack and stroke. In the present study, researchers investigated whether physical fitness earlier in life can predict how elastic the blood vessels are in older age.

The study is based on data from the Swedish longitudinal study SPAF‑1958, led by Maria Westerståhl, senior lecturer at the Department of Laboratory Medicine, where 425 individuals were followed across adulthood. Participants were examined at ages 34, 52, and 63. The researchers assessed fitness using a cycle ergometer test, analysed blood samples to study lipids, and measured arterial stiffness at age 63 using a non-invasive method.

Fitness more important than blood lipids

The results show that individuals with higher fitness at ages 34 and 52 had more elastic arteries at age 63. The association remained even after accounting for factors such as blood pressure, body weight, smoking, and cholesterol levels. However, neither cholesterol nor more advanced measures of so-called “good” HDL cholesterol could predict arterial stiffness.

“Our findings show that good physical fitness early in life is linked to vascular health later in life, independently of traditional risk factors,” says Andrea Tryfonos, postdoctoral researcher at the Department of Laboratory Medicine, Karolinska Institutet.

According to the researchers, the results suggest that regular physical activity may have long-term effects on cardiovascular health that are not captured by blood lipids and other common risk markers alone.

“This highlights the importance of maintaining good fitness from early adulthood to reduce the risk of cardiovascular disease,” says Andrea Tryfonos.

Next step

The researchers are now planning a follow-up of the participants at age 68 to investigate how changes in fitness over time affect vascular health later in life.

The study was conducted in collaboration with the division of clinical physiology and the division of clinical chemistry at the department of laboratory medicine, as well as Karolinska University Hospital in Huddinge. Information on funding and potential conflicts of interest is not available in the provided material.

Source: Karolinska Institutet

Up to 10 Hours of Exercise a Week Needed for Substantial Heart Benefits

Current exercise guidelines are too low, suggest researchers

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Adults should aim to do between 560 and 610 minutes a week of moderate to vigorous physical activity to achieve a substantial reduction in the risk of heart attacks and stroke, suggest the findings of an observational study published online in the British Journal of Sports Medicine.

This is between 3-4 times higher than the current public health recommendation that adults do at least 150 minutes a week of moderate to vigorous physical exercise such as brisk walking, running or cycling.

People who are less fit need to do slightly more exercise than those who are very fit to get the same cardiovascular benefits, the study suggests.

The researchers say that the current one-size fits-all advice on exercise may need to be changed and replaced with personalised targets according to an individual’s fitness level.

Cardiorespiratory fitness varies greatly and is a strong predictor of cardiovascular health. Low cardiorespiratory fitness is strongly associated with an increased risk of heart attacks, strokes and early death, the researchers point out.

A simple way to assess cardiorespiratory fitness is by measuring VO2 max – the maximum rate of oxygen the body consumes and uses during intense exercise. This measures how efficiently the heart, lungs and muscles deliver and use oxygen.

Less fit individuals need to do more exercise to get the same benefits

Researchers from Macao Polytechnic University, China, set out to look at how both exercise levels and cardiorespiratory fitness, as measured by VO2 max, affected the risk of cardiovascular disease.

The study included data from 17 088 people who were taking part in a UK Biobank study between 2013 and 2015. The average age was 57 years and 56% were female and 96% were white.

The study participants wore a device on their wrist for seven consecutive days to record their typical exercise levels and had completed a cycle test to measure their estimated VO2 max.

Data on smoking status, alcohol intake, self-related health and diet, body mass index, resting heart rate and blood pressure were also included in the analysis.

During an average follow up period of 7.8 years, there were 1233 cardiovascular events, including 874 atrial fibrillation, 156 myocardial infarction, 111 heart failure and 92 stroke events.

Those adults who met the 150 minute a week guideline on exercise experienced a modest 8-9% reduction in cardiovascular risk, the study found. This was consistent across all levels of fitness.

In order to achieve substantial protection, classed as a greater than 30% risk reduction, between 560 and 610 minutes of moderate to vigorous exercise a week was needed. However, this level of exercise was only achieved by 12% of people in the study.

The analysis found that those individuals with the lowest fitness needed approximately 30-50 additional minutes per week compared with those with high fitness to achieve equivalent benefits.

For example, to achieve a 20% reduction in the risk of cardiovascular events, 370 minutes of moderate to vigorous exercise was needed for those at the lowest fitness compared to 340 minutes for those at the highest fitness levels.

The researchers say, “This finding highlights the steeper challenge faced by deconditioned populations.”

This is an observational study and as such no firm conclusions can be drawn about cause and effect. The researchers acknowledge that the study group could have been healthier and fitter than the general population. Another limitation was that cardiorespiratory fitness was estimated and sedentary time or less vigorous exercise was not measured.

The researchers say their findings confirm that current guidelines provide a robust universal minimum for cardiovascular protection. But they add that there should be stratified advice to help guide motivated patients to do more to protect their heart health.

“Future guidelines may need to differentiate between the minimal moderate to vigorous exercise volume required for a basic safety margin and the substantially higher volumes necessary for optimal cardiovascular risk reduction,” they conclude.

Source: The BMJ Group

Weightlifting Beats Running for Glycaemic Control, Researchers Find

Study shows that resistance training outperforms endurance exercise in improving insulin sensitivity in obesity and Type 2 diabetes models.

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Running may help burn calories, but when it comes to preventing diabetes and obesity, pumping iron might have the edge, according to preclinical findings from Virginia Tech scientists at the Fralin Biomedical Research Institute at VTC.

The research, published in the Journal of Sport and Health Science, compared the effects of endurance and resistance exercise in mice fed a high-fat diet, a widely used model of obesity, hyperglycaemia, and Type 2 diabetes.

A team led by exercise medicine researcher Zhen Yan found that while both running and weightlifting helped the body clear excess sugar from the blood, resistance training was more effective in reducing subcutaneous and visceral fat, improving glucose tolerance, and lowering insulin resistance – key factors in preventing and managing diabetes.

“We all want to live a long, healthy life,” said Prof Yan, director of the Center for Exercise Medicine Research. “We all know the benefits of regular exercise. There is plenty of evidence in humans that both endurance exercise, such as running, and resistance exercise, such as weightlifting, are effective in promoting insulin sensitivity.” 

But while both support metabolic function, a rigorous side-by-side comparison was lacking. Is one type of exercise better than the other? 

What they did

To conduct the first direct, controlled comparison, members of the research team built something that had not previously existed: a mouse model of weightlifting.

In this model, mice lived in specially designed cages where food was accessed through a hinged, weighted lid. To eat, the mice had to lift the lid while wearing a small shoulder collar, causing a squat-like movement that engaged the muscle contractions people use during resistance exercise. The load was gradually increased over several days, mimicking progressive strength training.

For the endurance group, mice were given open access to a running wheel, an established model of aerobic exercise. Control groups included sedentary mice on either a normal or high-fat diet.

Over eight weeks, the researchers monitored weight gain, body composition, and fat distribution. They tested exercise capacity with treadmill runs, assessed heart and muscle function, and measured how well the mice regulated blood sugar. They also analyzed skeletal muscle tissue to study insulin signaling at the molecular level.

Using their novel model of resistance exercise, team members were able to directly compare how the two training styles affect obesity, blood glucose, and insulin sensitivity in a way that closely mirrors human exercise.

“Our data showed that both running and weightlifting reduce fat in the abdomen and under the skin and improve blood glucose maintenance with better insulin signaling in skeletal muscle,” Yan said. “Importantly, weightlifting outperforms running in these health benefits.”

Why this matters

Diabetes and obesity are major public health challenges, fuelled by sedentary lifestyles and high-fat diets. The findings underscore decades of clinical trials showing that endurance, resistance, and high-intensity interval training all reduce HbA1c while also lowering body mass index, blood pressure, and improving quality of life.

The new Virginia Tech study, which also involves collaborators from the University of Virginia, helps fill a critical gap by directly comparing voluntary running and weightlifting in a controlled, preclinical model of diet-induced obesity.

“The findings also bring good news for people who, for any number of reasons, cannot engage in endurance-type exercise,” Yan said. “Weight training has equal, if not better, anti-diabetes benefits.”

The researchers also saw changes in skeletal muscle signaling pathways that could inform new drug therapies for Type 2 diabetes.

Interestingly, the benefits of resistance training were not explained by changes in muscle mass or exercise performance, suggesting unique metabolic mechanisms at play.

Yan said the study underscores the idea that, while popular drug interventions like GLP-1 agonists can help with diabetes management and weight loss, they do not replace the unique, accessible, and comprehensive benefits of a well-balanced exercise programme. 

“The take-home message is that you should do both endurance and resistance exercise, if possible, to get the most health benefit,” said Yan, who is also a professor in the Department of Human Nutrition, Foods, and Exercise in the College of Agriculture and Life Sciences at Virginia Tech. 

Source: Virginia Tech

Gender Equality Universally Linked to Physical Capacity

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Fitness amongst young adults varies widely from one country to another, and is strongly associated with both socioeconomic development and gender equality, a new study from Karolinska Institutet published in the Journal of Sport and Health Science reports. The results indicate that levels of development and gender equality in a society can affect differences in physical capacity and therefore public health in general.

Cardiorespiratory fitness (CRF) is an important factor of health and life-expectancy. For this present study, researchers systematically reviewed data from 95 studies in 24 countries involving a total of over 119 000 adult participants.  

CRF is measured by what is known as the VO2peak, which is the highest oxygen uptake a body achieves during physical exertion.  

The group, which included researchers from KI and Shanghai University of Sport, studied correlations between CRF, the Human Development Index (HDI) and the Gender Inequality Index (GII).  

HDI is a measure of societal parameters like education, income and life-expectancy, while GII reflects differences between women and men in terms of health, education and labour. 

Clear correlation in women 

The results show that people in countries with a higher HDI were, on average, fitter, a correlation that was particularly salient amongst women, where young women in countries with a medium HDI had a higher VO2peak than women in countries with a low HDI (31.2 versus 28.5mL/kg/min). However, a further HDI increase from medium to high gave only small improvements. 

“Our results suggest that societal structures impact greatly on people’s access to exercise and thus their fitness levels,” says the study’s lead author Nicolas Pillon, researcher at the Department of Physiology and Pharmacology, KI. 

The study also shows that higher gender equality (a lower GII) correlates with a higher level of fitness in both women and men. Again, the difference was the most notable amongst young women, who in countries with high gender equality had on average a 6.5mL/kg/min higher VO2peak than their peers in countries with low gender equality. 

“Our results underpin the importance of societal interventions and guidelines that reduce social and gender-related hindrances to physical exercise but point out that more research is needed from countries with a lower HDI, and on the obstacles facing different ethnic and socioeconomic communities,” says Barbara Ainsworth, researcher at Shanghai University of Sport and head of the study. 

Source: Karolinska Institutet

Aerobic Exercise may Help Prevent the Brain Fog from Chemotherapy

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