Can running protect you from the effects of ageing?
Death and taxes are said to be the only things that are certain in life. But it’s hard to disagree with Dr Hirofumi Tanaka, director of the Cardiovascular Ageing Research Laboratory at the University of Texas at Austin, when he says ‘ageing is an inevitable consequence of living.’ As the years pass, the candles on our birthday cake irrefutably take up more of the surface area.
‘Ageing is associated with many declines in body structures and systems, from a loss of bone mineral density to sarcopenia (a drop in muscle mass and strength) and a reduced aerobic capacity,’ says Dr Justus Ortega, professor of kinesiology at Humboldt State University.
A glance at the timeline over which most age-related declines occur, and you’d be forgiven for thinking that anyone pushing 30 is already heading down the slippery slope to old age. For example, a study in the Journal of Applied Physiology reports a 3-6 per cent drop in aerobic capacity per cent per decade, with this decline accelerating after the age of 45. Bone density peaks by the tender age of 30 and then begins to fall, while muscle mass plummets by a staggering 10 per cent per decade, beginning from 30-40 years of age (with concomitant decreases in strength and power). Lung capacity starts to fall in the mid-30s. And according to research from the University of Virginia, some aspects of cognitive function (namely a drop in abstract reasoning, brain speed and puzzle-solving test scores) decline from the tender age of 27. Oh, and flexibility and balance also deteriorate.
It’s a bleak picture, but thankfully, it isn’t the whole story. Recent UK studies published in the journals Aging Cell and Journal of Physiology looked at cyclists aged 55-79 who’d been active most of their lives. The cyclists were compared to sedentary age-matched peers and healthy but inactive young people – and it turned out that their cycling habit had enabled them to sidestep many of the factors commonly associated with ageing. Their thigh muscles did not show a marked deterioration in strength, the quality of their muscle fibres was well maintained and their metabolic health was good. They even had more ‘youthful’ immune systems, with as many T cells (cells produced by the thymus, which form part of the immune system) as the younger subjects in the study.
This is just one example of an ever-burgeoning body of research that shows many of the physical declines once attributed to ageing are actually the result of a sedentary lifestyle. ‘It could be said that it’s not so much that exercise slows down the ageing process as that not exercising accelerates it,’ says Ortega. And that, my running friends, puts us happily behind the curve.
The problem in the past, says Tanaka, is that researchers studying ageing were comparing young healthy adults with older, unhealthy sedentary adults – essentially, with those who were considered ‘normal’. Unsurprising, when the most recent UK Active Lives survey shows that that while 69 per cent of people aged 16-34 achieve the recommended 150 minutes of moderate physical activity per week, the figure drops to 66 per cent in the 35-54-year-old age group and 60 per cent in the over 55s.
‘It was only when we started studying older, physically active adults, such as Masters runners, that we found that many of the age-related defects were either absent or attenuated,’ Tanaka says.
His research revealed that while average aerobic capacity (known also as VO2 max, and considered an independent risk factor for cardiovascular disease) among sedentary women aged 50-59 was 26.2ml/kg/min, in female runners the same age it was 42.72ml/kg/min. The runners had also evaded the weight gain so typical of ageing – weighing 11kg less, on average, than their inactive peers.
Slowing the clock with exercise
‘Exercise can change the trajectory of ageing,’ says Dr Lyndon Joseph, Exercise Physiologist and Program Officer in the Division of Geriatrics and Clinical Gerontology at the National Institute on Aging, part of the US National Institutes of Health. ‘The physiologic systems take longer to decline, and the point at which declines – and the diseases associated with ageing – begin, is pushed back. Yes, you lose muscle strength and mass, but not as fast as someone who is sedentary. Yes, you lose functional capacity, but it was higher in the first place, so you still end up better off.’
That helps to explain why runners are 25-40 per cent less likely to die prematurely than non-runners and why their typical lifespan is three years longer. It also explains why at 75 years of age, the late great Ed Whitlock could knock off a 19.07 5K and 3.04.54 marathon while most of his contemporaries were struggling to get up from their armchairs.
The ways in which exercise helps defy aspects of ageing are many and varied. One of the theories as to why physical activity helps ameliorate some of the effects of ageing relates to its impact on the very fabric of our being – our DNA.
DNA is found in every single cell in the body, tightly packed within the cell nucleus in two long strands. Each strand has a ‘cap’ called a telomere on either end, which helps to protect it. But as we age, telomeres shorten and over time, can become too short to protect the DNA. Then the DNA dies, causing the cell to degenerate (known as ‘senescence’).
Research has suggested links between telomere length and various chronic conditions associated with ageing, including cardiovascular disease, type 2 diabetes and some neurological conditions and cancers.
‘We know that, in general, people with shorter telomeres die sooner and are more likely to develop chronic diseases,’ says Dr Larry Tucker, professor of exercise sciences at Brigham Young University. But studies suggest that physical activity helps to preserve telomere length. Tucker’s research, involving over 5000 adults, found that while telomere lengths did shorten year after year with age, the most highly active subjects – those who did the equivalent of 30-40 minutes of running a day five days a week – had notably longer telomere lengths than the sedentary people. The difference was equivalent to a biological age advantage of nine years.
‘Moderate exercise was still valuable and had some benefit, but it was really those high levels of physical activity that made the difference,’ says Tucker. A twins study at King’s College, London, found that among identical twins with the exact same DNA, it was the most active of each pair who had the longest telomeres, showing that this is something we have the power to change through our lifestyle choices.
Ageing is typically associated with a hardening and narrowing of the central arteries, which carry oxygenated blood from the heart to the working muscles. This ‘arterial stiffness’ is considered an independent risk factor for cardiovascular and other diseases – not to mention having a negative impact on our capacity for exercise.
‘When the arteries stiffen, your heart has to work harder to push blood out, which gradually enlarges it,’ explains Tanaka. ‘In addition, hardened arteries are not able to buffer the pulsatile stress that comes from the heart every time it beats, allowing it to be transmitted to vital organs (the brain, kidneys and eyes, for example), causing damage.’
But guess what? ‘Regular running can keep the arteries young,’ says Tanaka. His research found that in Masters endurance athletes, the age-associated stiffening of arteries was either absent or significantly less prevalent. ‘Regular aerobic exercise seems to prevent the constriction of the smooth muscle cells that line the arterial wall, making it stiffer and harder,’ he explains. ‘It also reduces sympathetic nervous system activation (the ‘fight or flight’ response) which constricts blood vessels and raises arterial pressure.’ It’s possible that long-term aerobic exercise has a favourable effect on the structure of the arteries, too – increasing elastin content and inhibiting collagen activity.
But the cardiovascular system isn’t just concerned with how much oxygen the heart can transport – it’s also about how efficiently that oxygen can be used to produce energy. This is determined by the mitochondria, the mini energy factories that reside in every single cell in the body, where energy is produced by coupling oxygen with a substance called ATP. As we get older, the mitochondria become less efficient at generating energy – so the overall ‘oxidative capacity’ (measured in microlitres of oxygen consumed per gram of muscle per hour) of our muscles drops.
‘As we age, the inner membrane of the mitochondria degrades as a result of oxidative damage, which means less coupling goes on,’ explains Ortega. Also, the prevalence of enzymes (chemicals that aid the coupling process) declines.
But in runners, these changes don’t seem to happen. ‘Our studies have found that older runners’ muscles are as efficient at generating energy as younger people’s – and a lot more efficient than their age counterparts,’ says Ortega. ‘This mitochondrial efficiency is one of the reasons why running economy does not seem to decline in concert with age.’
It’s worth stressing that walkers in Ortega’s study did not maintain mitochondrial efficiency. ‘It is only vigorous exercise – where you can only get out 2-3 words in conversation – that provides the necessary stimulus for mitochondrial change,’ he says.
Exercise intensity is also key when it comes to bone health. According to Wolff’s Law, bone responds to load by remodelling itself to become stronger and denser. This process is kept in tight control by cells called osteoclasts, which break bone tissue down and osteoblasts, which form new bone tissue. The amount of load-bearing activity we expose our bones to in younger years plays a major role in the peak bone mass we achieve. For example, research shows that young runners have greater bone mineral density in their thigh bones than non-runners and that running – a high-intensity load-bearing activity – stimulates bone strengthening in the shin bones more than does cycling (non-weight-bearing) or walking (low intensity).
But after around 30 years of age, we begin to lose bone density as the balance shifts towards bone resorption, causing a decline in bone density and strength. This is a gradual process, although in women, it speeds up considerably around the time of the menopause because until that point, oestrogen exerts a protective effect on bone tissue. ‘It is more of a challenge to see the positive effects of exercise on bone in older people because the skeletal response to loading declines as we age,’ says Dr Jinhu Xiong, from the centre for musculoskeletal disease research at the University of Arkansas for Medical Sciences.
So can being active prevent this loss? The evidence is a mixed bag. A Cochrane review of the available evidence found that, on average, post-menopausal women who exercised had 0.85 per cent less bone loss at the spine than those who didn’t exercise, and 1.03 per cent less at the hip.
French researchers looking specifically at the effect of running on bone concluded that it had only a modest effect while a 2018 study in the Archives of Osteoporosis looking at bone mineral density in Masters sprinters and endurance runners versus age-matched controls found hip bone density in sprinters was 14 per cent higher while among endurance runners, it was barely different from non-active people. Spine bone density was also higher in the sprinters compared to the other two groups.
‘The key point is that bone has to be loaded, and the load has to be above a certain threshold to have an anabolic effect,’ says Xiong. ‘High-intensity sprinting seems to be more effective than long-distance running, because it puts a lot more load on bone.’
It’s a sound reason to include sprinting in your regular training regime, says Professor Jamie McPhee, one of the 2018 study authors whose research at Manchester Metropolitan University focuses on the maintenance of athletic performance with ageing. ‘Firstly, the overall muscular forces are high and secondly, the forces are applied through muscles onto bones at a very high rate of force development. This combination of high force and rapid contraction provides a great stimulus to bones. Actions like jumping and hopping are beneficial for the same reason.’
But bear in mind that the sprinting won’t help your upper body bone health. ‘Only the skeletal sites that directly experience loading will benefit,’ says Xiong. That’s why resistance training that loads a whole range of different joints becomes increasingly important as we age.
Keeping your brain in shape
It’s not just the body where age wreaks its effects. As we get older, our brains shrink. The number of connections – called synapses – between brain cells drops. The formation of new neurons (the building blocks your nervous system uses to send signals to every part of your body) tails off and the secretion of chemical messengers drops. All these factors impact on aspects of cognitive function, from memory and learning to problem-solving and concentration.
But… (getting déjà vu yet?) in regular exercisers, these changes are slower, or don’t happen at all.
‘From longitudinal studies, it does appear that exercise through middle and older age reduces cognitive decline and may limit or attenuate age-related atrophy in brain structures,’ says Professor David Raichlen from the Department of Biological Sciences at the
University of Southern California. ‘We don’t fully understand the mechanisms behind why exercise helps the brain. Increased blood flow is one good possibility, and there is mounting evidence that exercise-induced neurogenesis in the hippocampus is likely another strong candidate.’
The effect of aerobic exercise on neurogenesis (the production of new neurons) in the hippocampus (the part of the brain associated with learning and memory) was first observed in rodents by researchers at the Salk Institute over 20 years ago. Having established that mice with access to a running wheel showed increased neurogenesis, the researchers then tested running mice versus non-running mice in a maze and found that two to four months of running improved the rodents’ learning. This suggested that exercise could also enhance neuroplasticity – the ability of the brain to form new connections and pathways.
In humans, a high level of aerobic fitness has been found to be protective against a shrinking hippocampus with ageing. In fact, a year-long exercise intervention in older adults (average age, 67) conducted at the University of Pittsburgh increased hippocampal volume by two per cent, effectively turning the clock back 1-2 years. Conversely, reduced blood flow to the brain, as a result of stiffened arteries has been associated with cognitive degeneration and vascular dementia.
‘We know that exercise slows cognitive decline,’ says Joseph. ‘Mental acuity is sharper and executive function is better in regular exercisers. However, we don’t really know why. Blood flow to the brain is definitely a factor but we are still exploring what the circulating molecules in the blood are from exercise that exert such a positive effect.’
The University of Pittsburgh researchers found that increased hippocampal volume was associated with greater serum levels of a molecule called brain-derived neurotrophic factor (BDNF), which is believed to play a role in both neurogenesis and neuroplasticity.
But an intriguing new study points to another potential candidate. It’s a protein, called GPLD-1, which is produced mostly in the liver. Dr Saul Villeda and colleagues at the University of California discovered that levels of this protein were higher after a month of aerobic exercise – both in mice and in older adults. They also discovered that by chemically increasing their levels of GPLD-1, mice performed better in cognitive tests, regardless of whether they’d actually done exercise or not. ‘This is a remarkable example of liver-to-brain communication that, to the best of our knowledge, no one knew existed,’ says Villeda. ‘Our study suggests that exercise can counter age-related decline in regenerative capacity and cognition in the aged brain. Through this protein, the liver is responding to physical activity and telling the old brain to get young.’
Raichlen’s research offers a different perspective – one that suggests that the very process of running may be safeguarding your brain. ‘From an evolutionary perspective, links between physical activity and the brain are likely associated with the cognitive demands of foraging,’ he explains. ‘These demands include both motor control as well as spatial memory and executive functions (such as planning, attentional switching and decision-making). So, in a sense, physical activity – including running – is a cognitively demanding task.’ By scanning the brains of experienced endurance athletes with healthy non-runners, Raichlen found differences in functional brain connectivity. ‘These findings suggest that high-intensity aerobic activity requiring sustained, repetitive locomotor and navigational skills may stress cognitive domains in ways that may lead to favourable altered brain connectivity,’ he says.
Aside from cognitive attributes like memory and reasoning, a high level of physical fitness has also been associated with greater mental resilience – the ability to cope with new situations and environments.
That might be why research suggests that women who exercise regularly adjust to the physical and psychological changes associated with menopause – a landmark in female ageing – more successfully. A study from the University of Granada in Spain found that exercise helped ease severe physical and mental symptoms of menopause, while symptoms among a non-exercising control group got worse. Other research (from Liverpool John Moores University) found that four months of exercise reduced the number of hot flushes by 62 per cent, as well as dialling down the intensity of those that the women did still experience.
Older and wiser, not wider
One of the most-hated aspects of menopause (indeed, of ageing altogether) is weight gain. The average adult, male or female, gains 0.5-1kg per year from middle age onwards but once again, exercise can help you buck the trend. Tanaka’s study, mentioned earlier, found that the average weight difference between female runners aged 20-29 and age 60+ was 2kg. Compare that to the trajectory among sedentary women: an average weight increase between the same ages of 9kg.
Weight gain, of course, can result from simply eating more and moving less. But even if diet stays the same, the body is primed to gain weight as we age because of a drop in muscle mass and metabolic rate.
Studies report decreases in muscle mass of 3-10 per cent per decade from the age of 30. Since muscle is more metabolically active than fat, a drop in muscle mass has a knock-on effect on metabolic rate. And the lower the metabolic rate, the fewer calories burned on a daily basis, leading to likely weight gain.
But as a runner, you’re already combating this unhappy sequence of events. ‘Metabolic rate does decrease with age, but the decay is slower among exercisers,’ says Dr Scott Trappe, director of the human performance laboratory at Ball State University. In one study, sedentary women experienced a 10 per cent decline in resting metabolic rate post-menopause compared to pre-menopause. But in endurance-trained women, this decline was not seen – and levels of body weight and body fat were lower. A study published in 2019 (on middle-aged men, this time) yielded similar findings – physical activity correlated with better preservation of lean body mass, less body fat and a higher resting metabolic rate.
Muscling in on ageing
While our running habit will help us maintain a healthier body composition as we age than our couch potato friends, it isn’t all good news when it comes to our muscles.
‘After the age of 30-40, total muscle mass declines by approximately one per cent per year,’ says Professor McPhee. ‘At 70, your muscles are likely to be around 30 per cent smaller than they were in your 30s.’ McPhee found that muscle mass was 30-44 per cent lower in the quads and 10-15 per cent lower in the tibialis anterior when comparing their older – healthy but inactive – subjects to younger people. Loss of muscle mass is greater in the legs than in the upper body.
There are two contributing causes of this decline. Firstly atrophy – that is, shrinkage – of individual muscle fibres. ‘A major cause of atrophy is disuse,’ says McPhee. ‘As people get older, they tend to become less active in day-to-day life and use their muscles less – so the fibres get smaller. But atrophy isn’t the whole story. We also lose muscle fibres.’ McPhee’s research has found 18-20 per cent fewer fibres in the thigh muscles of older adults compared to 20-somethings.
The reduction in muscle fibre numbers has been attributed to a loss of motor units (a motor unit is a nerve cell and the muscle fibres it enervates) with age, which has the effect of reducing the signals sent through the nervous system instructing muscles to contract. The more motor units, the more precise the instruction is for a muscle to contract,’ says McPhee. ‘As the connections between nerve cells and muscle fibres slowly erode, it eventually leads to loss of some of the affected fibres, because they no longer receive any instructions to contract.’
McPhee made a comparison of the number of motor units (a motor unit is made up of a motor nerve and the muscle fibres it stimulates to contract) in the muscles of older people and younger people and found far fewer in the older group. ‘There is a dramatic decrease in the number of nerves that send signals to the muscles,’ he says. ‘We don’t yet know why these motor nerves decline in older age.’
Declining muscle mass (and remember, smaller muscles are weaker muscles) is also related to how ‘old’ muscle responds to a training stimulus. ‘The anabolic response – the response that triggers growth – is blunted as we age,’ says McPhee. This is partly due to a drop in the levels of anabolic hormones in circulation, such as testosterone – but the muscle tissues themselves also become less responsive to these hormones. One reason for this seems to be fat infiltration of muscle tissue. ‘This interferes with the normal cellular response – for example, reducing responsiveness to insulin, raising the risk of type II diabetes.’
If you’re waiting for the bit where I tell you that runners are completely immune to these losses, brace yourself for some disappointment. In McPhee’s research, older endurance runners showed a similar and substantial loss in both muscle mass and motor units as healthy non-active older adults. Only sprinters – as well as older adults who regularly did strength training – preserved their muscle strength and size to levels comparable to non-athletic people much younger. That’s why McPhee recommends that distance runners include regular strength training and sprint work.
‘It is difficult to claim that running preserves muscle mass in the same way as resistance training does,’ agrees Dr Trappe. ‘However, as far as muscle metabolic health is concerned, it has far-reaching benefits – more capillaries in the muscles, better blood flow, more mitochondria and enzymes.’
The positive influence goes way beyond the muscles themselves, too, thanks to the release of substances called myokines, which have been found to have beneficial effects on a wide range of organs and systems, from body fat and the immune system to bone, the liver and the brain. ‘A myokine called IL-6 is released in response to exercise that communicates with the liver, regulating energy metabolism and stimulating glucose production,’ says Dr Trappe. Another myokine, irisin, appears to play a role in regulating body fat by increasing post-exercise oxygen consumption (the afterburn) and by inhibiting the formation of fatty tissue.
Regular aerobic exercise also increases levels of a glucose transporter called GLUT4, which helps to regulate blood glucose levels and improve insulin sensitivity, thereby reducing the risk of type II diabetes. ‘Think of GLUT4 as the “doorways” into the muscle, through which glucose can get in,’ says Trappe. ‘When we have more doorways, we can get more glucose in, which means less is circulating in the blood.’
You are probably getting the picture by now that while running is undoubtedly helping us age better, there are other actions we can take to round out our regimes.
But even if we religiously include all these elements, we need to accept the fact that we will get slower as we get older. While Whitlock’s 19.07 5K at 75 would leave many of us relative young’uns in his wake, he was capable of running 17.23 at 67 years of age, eight years earlier – and a decade later, at 85, his best performance was 24.03.99.
‘We do see a decline as we age, even in runners who continue to clock up five miles a day, five days a week into their 70s,’ confirms Joseph.
One age-related parameter that no amount of running appears to effect is maximum heart rate. Sedentary adults and active runners experience similar rates of declines in maximal heart rate as they get older, with a drop of approximately one beat per year. We also continue to see declines in aerobic capacity, which is often described as the ‘gold standard’ measurement of fitness. ‘In the past, people promoted the idea that if you exercise regularly, you can attenuate this decline,’ says Tanaka. ‘But in fact, endurance-trained adults (like runners) demonstrate greater rates of decline in VO2max with age.’
Before you kick off your running shoes in disgust, read on. ‘We think this is due to the law of initial baseline,’ Tanaka continues. ‘That is, runners have a very high VO2max to begin with, so they have much more ‘space’ for it to reduce as they get older. If we take baseline into account, the rate of decline is similar in sedentary and endurance-trained adults. But it’s important not to get too caught up with this idea of a decline. The key thing to remember is that runners and other regular exercisers have a greater VO2max at any given age, so they enjoy much better functional capacity throughout their lifespan.’
He points to a study on octogenarians, that found the VO2 max of Masters endurance athletes (38 mL/kg/min) was almost twice as high as that of their sedentary counterparts (21 mL/kg/min).
While VO2 max plays a key role in age-related performance declines, it’s not the sole culprit.
‘In my opinion, VO2 max is one of only several factors, including changes in tissue properties, neuromuscular changes, physiological changes and even sensory changes, such as vision, proprioception and vestibular function,’ says Ortega.
Ortega’s hunch on vestibular function is supported by a study published in the Journal of Aging and Physical Activity, which discovered that balance among runners was barely better than among non-exercisers. ‘Masters runners were able to balance on one leg with eyes closed for an average of 8 seconds, compared to 5 seconds in non-exercisers and 27 seconds in young healthy people,’ says McPhee, who was on the research team. ‘Running does not seem to stave off the deterioration in balance associated with ageing.’
There are also clear changes to stride pattern with age. ‘The most distinctive differences are that older runners run with a higher cadence and lower step-length compared to younger runners,’ says Dr Jessica Leitch, founder and CEO at gait analysis specialists Run 3D (run3D.co.uk). ‘This hold true at both self-selected and controlled speeds.’ A study from Wake Forest University (2015) found that stride length was around 20 per cent lower per decade after comparing runners between 20 and 60 years of age.
As stride length decreases, explains Leitch, so too do the vertical ground reaction force and the peak propulsive force (the force that acts to drive you forwards as you push-off the ground), yielding a weaker push-off and slower running speed. Other gait changes associated with ageing in runners include reduced knee flexion and, when running faster, greater hip adduction and more pelvic drop.
A major contributing factor to a decline in stride length, speed and propulsive force is dwindling strength in the plantar flexors – the muscles, including the calves, that you use to rise up on to your toes. ‘Ankle power during running can drop by almost 50 per cent between the ages of 20 and 80,’ says Leitch. ‘Older runners seeking to maintain stride length would benefit from including strengthening of the ankle plantar-flexor muscles in their programmes.’
There’s also a deterioration in flexibility – one study found a decline in hip flexion of 6-7 degrees per decade – and the loss of range of motion was not different between regular exercisers and non -exercisers. Other research comparing active people with non-active people found that flexibility did decline in both groups over a 5-year period, but the losses were more modest among the active folk.
Changes in the structure and composition of tendons may also play a role in a smaller, less powerful stride in older runners. And in injury risk. ‘Older runners are more susceptible to hamstring, calf, and Achilles tendon injuries, whereas younger runners are more prone to lower leg and knee injuries such as medial tibial stress syndrome (also known as shin splints) and iliotibial band syndrome (ITBS),’ says Leitch. ‘Older runners are also more susceptible to multiple running injuries per year.’
She recommends all older runners include a well-designed exercise programme in their training schedules. ‘Research suggests that running alone is insufficient to stop the decline in muscle strength or to prevent running-related injuries as we age,’ she says.
Slacking off?
There’s also an ‘elephant in the room’ reason as to why we might get slower as we age. Whether it’s consciously or subconsciously, we may simply not be training as hard. Think about it. You’re busier. You sit more, drive more, work more and often have to prioritise other things over training as you get older. And, says Tanaka, you may be influenced by the fact that others your age are doing less.
In addition, as VO2 max declines, you may find exercise more demanding than you used to, which could affect how much you do. Particularly intense sessions or long runs may take it out of you more than they used to and require longer to recover from. That was found to be the case in research looking at recovery from a 55km trail race. Compared to younger athletes, older runners (average age 46) recovered more slowly in all four parameters measured.
But there’s another altogether more fascinating possible cause. Dr Douglas Seals researches the biological and lifestyle factors that influence cardiovascular ageing at the University of Colorado at Boulder. ‘In rodent studies,’ he says, ‘a marked reduction in voluntary running distance has been observed through adult life, with old animals running less than 10 per cent of their young adult counterparts.’ In other words, older mice and rats simply don’t jump on the wheel as much. ‘This suggests that there is an intrinsic physiological process that occurs with ageing, that reduces the fundamental drive to be physically active,’ says Seals. ‘If so, that intrinsic process might reflect a “wisdom of the body” – a mechanism to preserve and defend homeostasis by reducing acute exercise-induced muscle damage or protecting cellular energy stores. Nobody knows for sure, but such observations provide evidence against the age-related decline in training being due only to sociological influences.’
Backing for this idea comes from studies on Masters athletes, where motivation and peer group support remain high, yet exercise intensity and volume still decline with age. Tanaka found that there was a significant but modest decline in average running mileage, frequency, and speed with advancing age in female endurance runners (all of whom had been running approximately ten years or more). Training intensity went down by about three per cent per decade.
According to World Masters Athletics, runners typically slow by seven per cent per decade between their 4th to 6th decades, with declines becoming steeper after that. ‘One way of avoiding the disconsolation of comparing your performances to your ‘younger’ self is to embrace age grading,’ says Dr Trappe.
There’s just one group of people who may find that their running performance follows an upward trajectory even as they age. Late starters. Joseph says you can still reap the benefits even if you only came to running later in life. ‘We have had 60-70-year olds in our studies seeing improvements in VO2 max, gait pattern and muscle function – not as dramatic as improvements in the young, but still significant.’
In a recent British study, untrained but otherwise healthy people aged up to 69 who took up running for six months saw improvements in aortic stiffness and central blood pressure (the pressure within the aorta) equivalent to knocking four years off their ‘vascular’ age – and it was the older, slower runners who reaped the greatest benefits.
Thirty years earlier, a landmark study in 1990 put nursing home residents, aged 90 and over, onto a resistance training programme for eight weeks. Muscle strength increased by an astonishing 174 per cent on average, with improvements in muscle size and function too – two participants no longer needed to use walking aids. While this might not sound like it has a lot to do with running, it does show that the body’s capacity to adapt to exercise has no deadline.
It’s still not entirely clear how – and how much – exercise protects us. But we do know that for any given age, those who are active are better off in terms of fitness and health than those who are not. ‘If exercise was a pill, doctors would be prescribing it all the time,’ says Joseph. While we can’t stop those candles from accumulating on our birthday cakes, we’ll sure as hell have the puff to blow them out for many years to come.
Alternative heart rate formula
- Dr Tanaka and Dr Seals were involved in a study that came up with an alternative method of determining maximum heart rate for Masters runners, which is more appropriate for their higher fitness and activity levels, compared to non-active people.
- Multiply your age by 0.7 and subtract that number from 208
- Eg. You are 50 years old.
50 x 0.7 = 35 208-35 = 173bpm (compared to 220-50= 170bpm)
Runners World, April 2021