Your walking distance may be more important than speed to fix chronic back pain
While walking is beneficial for reducing the risk of lingering chronic low back pain, experts say that it is how you walk that really matters.
Walking more is a bigger factor than how fast you walk, Norwegian researchers said on Friday.
'Our findings suggest that daily walking volume is more important than mean walking intensity in reducing the risk of chronic lower back pain,' they wrote in a study published in the journal JAMA Network Open.
The authors also found that walking for more than 100 minutes a day -- or an hour and forty minutes -- was associated with a 23 percent lower risk of chronic low back pain compared with walking fewer than 78 minutes a day. Walking 125 minutes or more daily also lowered the risk by 24 percent.
The study included data from more than 11,000 patients aged 20 years and older, who were a part of the Trøndelag Health Study.
Their health was first assessed during the years from 2017 to 2019. The authors later followed up from 2021 to 2023. Participants did not have chronic low back pain at the start of the study. To measure their walking, they wore accelerometers.
Following just over four years, 1,659 participants reported experiencing chronic low back pain.
They noted that participants with a higher walking volume tended to exercise more often and that the reduction in risk of chronic low back pain leveled off beyond walking for 100 minutes a day.
Still, they urged that these findings could inform policy related to the costly condition going forward.
The findings come after previous research that also identified being active as a way to alleviate chronic low back pain. Back pain affects more than a quarter of Americans. Another study last year found that people with chronic low back pain who walked 30 minutes a day for five days a week went twice as long without a recurrence as those who did not walk, according to UCLA Health. Approximately 70 percent of individuals experience a recurrence of low back pain within 12 months following recovery from an episode, Australian researchers found.
Walking can help to strengthen the muscles that support the spine, and increase circulation and joint mobilization, according to Healthline.
It is the sixth-most costly condition in the U.S. and can be incredibly debilitating, making even standing up or sitting at work a struggle.
'If confirmed by future research, these results could inform public health strategies aimed at preventing chronic low back pain, as well as complementing current guidelines that solely report on physical activity as a secondary prevention tool,' they said.
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The Sun
an hour ago
- The Sun
Do vitamin gummies actually work and should you give them to your kids? We grilled experts and tested them to find out
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Dr Rachel Ward, NHS GP (@drrachelwardGP), adds: 'The best way to get the vitamins we need is through a healthy, balanced diet and this would always be the way I would advise people to stay well. 'However, if you feel this is not possible - if you're excluding certain foods, for example - then supplements can be helpful. 'An exception is vitamin D. We get very little of it in our diets and we produce most of it in our skin when it is exposed to sunlight. 'We know that, especially in winter, many people in the UK become deficient in vitamin D and the NHS recommends that everyone takes supplements during autumn and winter and those at risk take them all year round.' 10 Do vitamin gummies work? 'AS long as the gummies provide the correct dose and the manufacturer routinely tests their levels, they can be just as effective as a vitamin or mineral supplement in powder, spray or liquid form,' Bahee says. 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Times
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- Times
Three easy summer soup recipes
A s the Spanish know, a chilled soup can be the most refreshing of starters or light summer lunches on a hot day. And the easiest too — all the work is done in advance so you literally have only to decant it from the fridge. There's an obvious flaw for the British cook, though: how do we know, if planning a menu more than a day or two in advance, if the sun is going to behave? It's all very well banking on the weather in the Mediterranean, but here we need a plan B up our sleeves. So here is my answer: three delicious soups that are as good hot as they are cold. If you choose to serve them hot, simply reheat them gently but don't let them boil or they will lose their vibrancy. • Read more recipes from our food experts I love the vibrant colour of this soup; it makes me happy just looking at it. Beetroot is rich in antioxidants and high in nitrates — one of the best vegetables you can eat. Buy it fresh (not precooked) as the taste is so much better. Serves 4 • 400g beetroot, boiled and skin removed • 1 tbsp olive oil• 2 celery stalks, finely chopped • 1 shallot, diced • Sea salt and black pepper • 1 litre vegetable stock • Juice of 1 lemon • 1 tbsp sherry vinegar • 1 tbsp crème fraîche • 50g hazelnuts, roasted and roughly chopped 1. Chop the boiled beetroot into cubes. Place a saucepan over a medium heat and add 1 tablespoon olive oil. Stir in the celery, shallot and beetroot. Season with salt and pepper. Cover and sweat for 10 min. 2. Pour the stock and lemon juice into the saucepan. Stir and cook until all the vegetables are soft. Blend the soup in a food processor until smooth. Stir in the sherry vinegar to taste. 3. Serve hot or cold with a swirl of crème fraîche and a sprinkling of hazelnuts on top. • Clodagh McKenna's healthy recipes for flavoursome midweek meals AARON GRAUBART FOR THE SUNDAY TIMES MAGAZINE. FOOD STYLIST: TONI MUSGRAVE. PROP STYLIST: LUIS PERAL This is my take on a classic gazpacho. If I'm serving it cold, I'll garnish it with extra diced cucumber and spring onion. Hot, I might add a swirl of crème fraîche and chopped tarragon. If you want to make this more substantial, add some crispy croutons and scatter over some grated parmesan. Serves 6 • 1kg very ripe tomatoes, diced• 100g slightly stale crusty white or sourdough bread • 2 red peppers, deseeded and diced• 1 cucumber, diced• 3 garlic cloves, crushed• 2 spring onions, chopped • 2 tbsp sherry vinegar• 200ml extra virgin olive oil• Sea salt and black pepper • 2 tbsp crème fraîche mixed with 1 tbsp fresh tarragon (optional) 1. Put the tomatoes, bread, peppers, cucumber, garlic, spring onions, sherry vinegar and olive oil in a food processor. Season with salt and pepper and blend until smooth. 2. If using, add a swirl of crème fraîche and tarragon. • Clodagh McKenna's asparagus recipes for spring starters and suppers AARON GRAUBART FOR THE SUNDAY TIMES MAGAZINE. FOOD STYLIST: TONI MUSGRAVE. PROP STYLIST: LUIS PERAL Frozen peas are brilliant. I'd always recommend them over peas in the pod, which lose sweetness quickly. A delicious vegetarian alternative to the pancetta is cubes of halloumi roasted and tossed in honey. Serves 6 • 50g butter • 2 onions, peeled and chopped • 2 potatoes, peeled and chopped • 3 garlic cloves, crushed • Sea salt and black pepper • 1 litre hot vegetable stock • 1kg frozen peas • 2 tbsp fresh mint • 100ml double cream • 80g smoked pancetta • Olive oil 1. Put the butter in a saucepan over a medium heat. Once it has melted stir in the onions, potatoes and garlic. Season and stir. Reduce the heat to low and cover with a lid. Give it a stir every couple of minutes and check to make sure that the vegetables aren't sticking to the bottom of the pan. Leave to cook for 5 min. 2. Pour in the hot stock and allow to cook uncovered for about 15 min. Pour in the frozen peas and cook for 3 min. Add the mint and cream and cook for another minute. 3. Blend the soup in a food processor and taste for seasoning. 4. Cook the pancetta in a frying pan with 1 tablespoon of olive oil until crisp, then transfer to a plate lined with kitchen roll to drain off the excess oil. 5. Serve the soup hot or cold, with a sprinkling of the crispy lardons on top. • Clodagh McKenna's easy Med-inspired summer recipes
BBC News
3 hours ago
- BBC News
'There's a huge amount that we don't understand': Why sperm is still so mysterious
How do sperm swim? How do they navigate? What is sperm made of? What does a World War Two codebreaker have to do with it all? The BBC untangles why we know so little about this mysterious cell. With every heartbeat, a man can produce around 1,000 sperm – and during intercourse, more than 50 million of the intrepid swimmers set out to fertilise an egg. Only a few make it to the final destination, before a single sperm wins the race and penetrates the egg. But much about this epic journey – and the microscopic explorers themselves – remains a mystery to science. "How does a sperm swim? How does it find the egg? How does it fertilise the egg?" asks Sarah Martins da Silva, clinical reader of diabetes endocrinology and reproductive biology at the University of Dundee in the UK. Almost 350 years on from the discovery of sperm, many of these questions remain surprisingly open to debate. Using newly developed methods, scientists are now following sperm on their migration – from their genesis in the testes all the way to the fertilisation of the egg in the female body. The results are leading to groundbreaking new discoveries, from how sperm really swim to the surprisingly big changes that occur to them when they reach the female body. "Sperm – or spermatozoa – are 'very, very different' from all other cells on Earth," says Martins da Silva. "They don't handle energy in the same way. They don't have the same sort of cellular metabolism and mechanisms that we would expect to find in all other cells." Due to the huge range of functions demanded of spermatozoa, they require more energy than other cells. Plus sperm need to be flexible, to be able to respond to environmental cues and varying energetic demands during ejaculation and the journey along the female tract, right up until fertilisation. Sperm are also the only human cells which can survive outside the body, Martins da Silva adds. "For that reason, they are extraordinarily specialised." However, due to their size these tiny cells are very difficult to study, she says. "There's a lot we know about reproduction – but there's a huge amount that we don't understand." One fundamental question that remained unanswered over almost 350 years of research: what exactly are sperm? "The sperm is incredibly well-packaged," says Adam Watkins, associate professor in reproductive and developmental physiology at Nottingham University in the UK. "We typically thought of the sperm as a bag of DNA on a tail. But as we've started to realise, it's quite a complex cell – there's a lot of [other] genetic information in there." The science of sperm began in 1677, when Dutch microbiologist Antoni van Leeuwenhoek looked through one of his 500 homemade microscopes and saw what he called "semen animals". He concluded, in 1683, that it wasn't the egg that contained the miniature and entire human, as previously believed, but that man comes "from an animalcule in the masculine seed". By 1685, he had decided that each spermatozoon contains an entire miniature person, complete with its own "living soul". Almost 200 years later, in 1869, Johannes Friedrich Miescher, a Swiss physician and biologist, was studying human white blood cells collected from pus left on soiled hospital bandages when he discovered what he called "nuclein" inside the nuclei. The term "nuclein" was later changed to "nucleic acid" and eventually became "deoxyribonucleic acid" – or "DNA". Aiming to further his studies of DNA, Miescher turned to sperm as his source. Salmon sperm, in particular, were "an excellent and more pleasant source of nuclear material" due to their particularly large nuclei. He worked in freezing temperatures, keeping laboratory windows open, in order to avoid deterioration of salmon sperm. In 1874, he identified a basic component of the sperm cell that he called "protamine". It was the first glimpse of the proteins that make up sperm cells. It took another 150 years, however, for scientists to identify the full protein contents of sperm. Since then, our understanding of sperm has moved on leaps and bounds. But much still remains a mystery, says Watkins. As scientists have started to better understand early embryonic development, he adds, they are realising that sperm doesn't just pass the father's chromosomes on, but also epigenetic information, an extra layer of information that affects how and when the genes should be used. "It can really influence how the embryo develops and potentially the lifelong trajectory of the offspring that those sperm generate," says Watkins. Sperm cells begin to form from puberty onwards, made in vessels within the testicles called seminiferous tubules. "If you look inside the testes where the sperm are made, it starts as just a round cell that looks pretty much like anything else," says Watkins. "Then it undergoes this dramatic change where it becomes a sperm head with a tail. No other cell within the body changes its structure, its shape, in such a unique way." It takes sperm about nine weeks to reach maturity within the male body. Unejaculated sperm cells eventually die and are reabsorbed into the body. But the lucky ones are ejaculated – and then the adventure begins. After ejaculation, each of these tiny cells must propel themselves forward (alongside their 50 million competitors) using their tail-like appendages to swim for the egg. And while you may have seen plenty of videos of tadpole-like sperm swimming around, in fact scientists are only just beginning to understand how sperm really swim. It was previously thought that the sperm's tail – or flagellum – moved side to side like that of a tadpole. But in 2023, researchers at the University of Bristol in the UK found that sperm tails follow the same template for pattern formation discovered by mathematician and World War Two codebreaker Alan Turing. In 1952, Turing realised that chemical reactions can create patterns. He proposed that two biological chemicals moving and reacting with each other could be used to explain some of nature's most intriguing biological pattern formations – including those found in fingerprints, feathers, leaves and ripples in sand – an idea known as his "reaction-diffusion" theory. Using 3D microscopy, the Bristol researchers discovered that a sperm's tail – or flagellum – undulates, generating waves that travel along the tail to drive it forward. This is significant as understanding how sperm move can help scientists to understand male fertility. So, now the sperm are on the move. They travel through the cervix, into the womb and up the oviducts – tubes that eggs travel down to reach the womb, known as the fallopian tubes in human females – in search of the egg. But here we hit another gap in knowledge, because scientists don't fully understand how sperm actually find their way to the egg. Spermatozoa which are healthy and take the right route are rare. Many take a wrong turn in the maze that is the female body – and never even make it near the goal line. For the ones that do find their way to the fallopian tubes, scientists think that they may be guided by chemical signals emitted by the egg. One recent theory is that sperm may use taste receptors to "taste" their way to the egg. Once the sperm find the egg, the challenge is not over. The egg is surrounded by a triplicate coat of armour: the corona radiata, an array of cells; the zona pellucida, a jelly-like cushion made of protein; and finally the egg plasma membrane. The sperm cells have to fight their way through all the layers, using chemicals contained in their acrosome, a cap-like structure on the head of a sperm cell containing enzymes that digest the egg cell coating. However, what prompts the release of these enzymes remains a mystery. Next the sperm use a spike on their "head" to try and break their way in to the egg, thrashing their tails to force themselves forwards. Finally, if one sperm makes contact with the egg membrane, it is engulfed and can complete fertilisation. Human cells are diploid. This means they contain two complete sets of chromosomes, one from each parent. If more than one sperm were to fuse with the egg, a condition called polyspermy would arise. Nondiploid cells – ones with the incorrect number of chromosomes – would develop, a condition lethal to a growing embryo. To prevent this from happening, once a sperm cell has made contact with it, the egg quickly employs two mechanisms. First, its plasma membrane rapidly depolarises – meaning it creates an electrical barrier that further sperm cannot cross. However, this only lasts a short time before returning to normal. This is where the cortical reaction comes in. A sudden release of calcium causes the zona pellucida – the egg's "extracellular coat" – to become hardened, creating an impenetrable barrier. So, of millions of sperm that set out on the journey, only one – at most – gets to do its job. The sperm's epic journey culminates in its fusion with the egg. Today, researchers are still attempting to uncover the identity and role of cell surface proteins that could be responsible for sperm-egg recognition, binding and fusion. In recent years, several proteins have been identified – albeit in mice and fish – as being crucial for this process, but many of the molecules involved remain unknown. So, for now, how the sperm and egg recognise each other, and how they fuse are yet more mysteries that remain unsolved. One way researchers are hoping to shed light on sperm is by studying species other than our own, says Scott Pitnick, a professor of biology at Syracuse University in New York. Human sperm cells are microscopic, so we can't see them with the naked eye. But some fruit fly species produce sperm cells 20 times their own body length. That would be like a man producing sperm the length of a 40m (130ft) python. Pitnick engineers the heads of fruit fly sperm so that they glow. This means he can watch them as they travel through dissected female fly reproductive tracts, revealing new details about fertilisation at the molecular level. "Why do males in some species make a few giant sperm?" asks Pitnick. "The answer, it turns out, is because females have evolved reproductive tracts that favour them." That's "not really much of an answer", he adds, because it's just the redirects the question: why have females evolved this way? "We still don't understand that at all." But it does teach us that sperm as they exist in the male body is only half the story, says Pitnick. "There's a massive sex bias historically in science. There's been this obscenely biased male focus on male traits. But it turns out that what's driving the system is female evolution – and males are just trying to keep up." Sperm, Pitnick says, are the most diverse and rapidly evolving cell type on Earth. Why sperm have undergone such dramatic evolution is a mystery that has stumped biologists for more than a century. "It turns out the female reproductive tract is this incredibly, rapidly evolving environment," says Pitnick, "and we don't know much about what sperm do inside the female. That is the big, hidden world. I think the female reproductive tract is the greatest unexplored frontier for sexual selection, theory and speciation [the process by which new species are formed]." The fruit fly's long-tailed sperm, suggests Pitnick, could be considered an ornament – much like a deer's antlers or a peacock's tail. Ornaments are a "sort of a weapon in evolution", explains Pitnick. More than just a defence from predators, ornaments like antlers and horns often have two roles to play. "A lot of these weapons are about sex, and usually male-male competition. The [fruit fly's] long sperm flagellum really meets the definitional criteria of an ornament. We think the female tract has traits that bias fertilisation in favour of some sperm phenotypes over others." We know a lot about pre-mating sexual selection, Pitnick says. "Say, it's prairie chickens dancing out on a grassland, or a bird of paradise displaying in a rainforest. It's motion, it's colour, it's smells?" Processing this sensory input, explains Pitnick, leads to decision making – whether the pair mate or not. But, Pitnick says, the sexual selection that goes on inside the female after mating – and how this drives the evolution of sperm – largely remains a mystery. "We still understand very little about the genetics of ornaments and preferences," he says. To fully understand sperm, we need to think about how the entire lifecycle of the sperm – and the female body, explains Pitnick, plays a huge role in the sperm's development. "Sperm are not mature when they finish developing in the testes, they're not done developing." Complex – and critical – interactions occur between the sperm and the female reproductive tract, he says. "We're now spending a lot of time studying what we call post-ejaculatory modifications to sperm across the whole animal kingdom." Even as scientists are unravelling the many and varied processes a sperm goes through in order to achieve fertilisation, other research is leading to real concern about the current state of human sperm. Men produce close to a trillion sperm during one lifetime, so it might be hard to imagine that sperm are in trouble. But research suggests sperm counts – the number of sperm in a sample of semen – are tumbling globally and the decline appears to be accelerating. More like this:• How pollution is causing a male fertility crisis• Pre-eclampsia: The deadly mystery scientists can't solve• Fewer than half of IVF cycles are successful. These scientists are trying to change that According to a 2023 report published by the World Health Organisation (WHO), around one in six adults worldwide experience infertility – and male infertility contributes to roughly half of all cases. (It's also worth noting that many people around the world are not having as many children as they want for other reasons too, such as the prohibitive cost of parenthood, as a recent United Nation population Fund report highlighted). Pollution, smoking, alcohol, poor diet, lack of exercise and stress are all thought to impact male infertility. Yet for the majority of men with fertility problems, the cause remains unexplained. (Read more about the decline in sperm quality around the world). "With all those moving parts, there are so many things that could go wrong," says Hannah Morgan, a post-doctoral research associate in maternal and fetal health at the University of Manchester, UK. "It could be a mechanism: it doesn't swim very well, so it can't get to the egg. Or it could be something more intricate within the head of the sperm, or other regions of the sperm. It's so specialised in so many different ways, that lots of little things can go wrong." One way to see if a man may be infertile is to look inside the sperm, says Morgan. "How does the DNA look? How is it packaged? How fragmented is it? To break open the sperm, there's a whole range of stuff you could look at. But what is a good or bad measurement? We don't actually know." Perhaps by unravelling the mystery of sperm and how they function, Morgan says, we might begin to understand male infertility too. -- For trusted insights into better health and wellbeing rooted in science, sign up to the Health Fix newsletter, while The Essential List delivers a handpicked selection of features and insights. For more science, technology, environment and health stories from the BBC, follow us on Facebook, X and Instagram.
