An Epitaph by Degrees: Physical Activity into Older Age

Illustration credit: Grace Sim (

On a quest to get her Ph.D., Karen Hancock aims to learn how to motivate older adults to exercise more.

Serpentimes readers won’t need convincing of the plethora of benefits from leading a physically active life – we already know that there is plenty of high-quality evidence that the more exercise of different kinds that we do (with appropriate recovery), the greater the chances of living longer, with better-preserved mental powers and physical independence. I know of a few Serpies who work hard to encourage their parents to be as physically active as possible, not only to delay and shorten dependence in old age, but also for the many wellbeing benefits and opportunities for socialising that exercise brings, especially when practised outdoors. Parents, however, do not always welcome advice from their children.

Even beyond our atypically athletic echo-chamber, there are few in the wider population who don’t know that a varied diet of physical activity improves health and wellbeing, even for people with serious medical conditions like heart disease, diabetes or cancer. “Exercise is medicine”, doctors proclaim. According to Public Health England (PHE), in 2015/16, 61% of adults in England met the recommended minimum level of physical activity, i.e. the 150 minutes a week of moderate-to-vigorous physical activity that the four Chief Medical Officers of the UK say is needed by adults of all ages for ‘good health’. But 26% of the population was classed as ‘inactive’ because they don’t reach 30 minutes per week. If those figures paint the picture of a more active population than you would have guessed, you are almost certainly correct. PHE’s data come from self-reports, which are much more optimistic than objective, accelerometer-measured levels. Moreover, even on a self-reported measure, only 31% of men and 23% of women met both the aerobic and the other, less well-known ingredient of the Chief Medical Officers’ exercise prescription: at least twice-weekly strength and balance training to reduce the risk of falls and slow age-related sarcopenia – muscle-wasting at a rate of around 5-10% per decade that begins around age 50.

And yet despite the weight of evidence about benefits, the pervasive advice to exercise more, and the reduced time commitments from work and family that advancing age often affords, rates of physical activity decline markedly from about age 50, both in duration and average intensity (see chart below). Lack of time is the most-often cited barrier to exercise by working-age adults; health issues are the top-cited barrier by older and retired adults. Motivations to exercise also change over the life-course, with a desire to improve how one looks being important to younger people, and health-improvement more of a motivator for older people. Successive governments have tried to encourage the population to become more active, but have failed to move the dial appreciably. People do not seem to be responding to medical advice. Are people irrational, given that even a small increase in physical activity by the inactive brings considerable health gains if sustained? And the health gains increase – albeit at a diminishing marginal rate per hour of exercise – to at least five times the recommended minimum levels according to a number of studies. Too much time spent sitting is far more dangerous to health than large amounts of physical activity. So why don’t more people – especially older people who generally have more free time, and are more motivated to improve their health – devote more of it to health-improving physical activity?

In the study of physical activity and exercise, a common finding is that people are full of good intentions but often fail to carry them out – known as the ‘intention-behaviour gap’. The title of a widely-cited article in the top economics journal (the American Economic Review) “Paying Not to Go to the Gym” neatly sums up that problem. People procrastinate and make excuses. Exercise can seem less appealing than staying on the sofa when the planned exercise time approaches. Who amongst us has not known the pre-training feeling of not being up for a session, of tricking ourselves into starting a session by saying to ourselves ‘I’ll just run one mile/one repetition and then see how I feel’, but almost never stopping after one, and never regretting it afterwards? That remembered sense of achievement, and the compulsion that a well-established habit brings, are what help to propel us over the doorstep on those dark mornings in winter. Similar mental processes can be taught to exercise novices – such as breaking a seemingly-daunting task down into smaller and more feasible chunks and encouraging people to remember how good they feel after trying something new, so they can access that memory more easily in the future. As a coach for more than two decades, and a competitive runner for more than five, the power of thinking and self-talk in spurring us on to achieve more than we might have believed has always fascinated me.

In my professional life I am an economist, with a long career working in public policy. The standard neoclassical economic theory we are taught as undergraduates assumes people are rational and weigh up costs and benefits carefully when making decisions, including the decision to invest in one’s health and fitness by exercising. A neoclassical economics approach would reason that if people are under-exercising it’s because of personal preferences, or perhaps some failure to be aware of all the relevant information about costs and benefits. Policy solutions in this world populated by homo economicus could include providing more and more accessible, information about exercise opportunities and benefits, and perhaps subsidising access for those of limited means.  But such solutions have not moved many, as already noted.  The behavioural variant of economic theory – which includes more realistic psychological insights about how people actually behave – provides a more promising basis for understanding the seemingly-irrational decision to shorten one’s life by staying on the sofa. Behavioural economists see people as ‘boundedly rational’, i.e. they use short-cuts and heuristics when making decisions in order to economise on cognitive effort. Being influenced by social norms, habits, or persuasive, rather than informative, advertising is essentially taking a cognitive short-cut to making a decision.  The main insight from behavioural economics is that human decisions are often context-dependent: changing the messenger, the frame of reference – e.g. presenting a decision as a gain rather than a loss – or changing the default option, all alter the decision context without changing anything objective about the balance of costs and benefits. And in testing, even small contextual changes like these have been shown to influence people’s choices. This means that behavioural economics is ultimately empirical – its findings come from experiments to affect decisions, rather than from reasoning about what homo economicus would do. All of which means there is plenty of empirical research to be done about how to help people make better choices.

Serpie Tash Sheel’s Mum has now completed 100 Park Runs after being encouraged to exercise by her daughter. Photo credit: Tash Sheel

In the same year Thatcher was elected PM, I embarked on a DPhil at Oxford on the topic of valuing non-market transactions in the National Accounts. For various valid reasons at that time, I DNF’d after one year. Although the counterfactual is unknowable, the lack of the ‘Dr’ title did not seem to impair my subsequent professional career. And yet, that DNF has always felt like an unscratched itch. So, when I retired from my Chief Economist civil service post in 2013 and said goodbye to long working hours, I began to formulate a bucket list of unfulfilled ambitions by thinking about what I would want my epitaph to be. Like Spike Milligan, I am also a hypochondriac – although far less amusing.  He had already used my favourite epitaph: “I told you I was ill”, so I cast around for something different. By 2015, I realised that I didn’t want to die without “Doctor” on my tombstone. But I needed to find a new research topic. My main learning point from my youthful DNF was that my research would need to be on a subject that would grip me for 6 years at least – the minimum number to complete a doctorate part-time. After about six months of cogitating, I hit on the idea of combining my life-long interest in sport and coaching with my professional interest in behavioural economics to try and make an impact on the important public policy issue of under-exercising.  I was also starting to realise from personal experience that ageing challenges one’s sense of physical capability, increases fears of hurting oneself and presents many temptations to retreat into an unchallenging, safe comfort zone, encouraged by well-meaning younger friends and relations. So, I decided to research how behavioural economics could help older people overcome their thinking barriers to exercise, as I knew there were many evidence gaps, it was an important issue, and would sustain my interest for a long time. I formally began work in April 2016 and was mightily relieved when, after much hard work, I passed my probation mini-viva in January 2018, which enables me to upgrade to PhD student status.

So at this point, I have formulated my hypotheses and topic more precisely and made a plan for my research. My main hypothesis is that the framing of public health messages about recommended minimum levels of physical activity – the 150 minutes a week prescription – is too off-putting to those currently on less than 30 minutes a week, and accords neither public value nor additional external motivation to do more. Prescribing a single absolute amount of physical activity might be medically sound, but by my reasoning does not help to motivate people. Surely, given that any increase in physical activity – however small – is beneficial and presumably more achievable, an incrementally-framed public message could result in greater behaviour change, especially among cautious older people. If I am right, changing the framing of the public health message would be relatively cheap to do, and even a small increase in physical activity would make it a cost-effective policy change. I am encouraged first by the existence of a decent-sized literature on the effects of message-framing and anchoring on physical activity and other healthy behaviour choices. My second confidence boost came from discovering last year – with a little translation help from Japanese Serpie Noriko Sugiyama – that the Japanese government introduced just such an incremental framing for their public messages on physical activity in 2013. They reasoned – but without much empirical evidence to substantiate their argument – that encouraging people to ‘add 10 minutes more’ to their current level of physical activity would have wider appeal than the 150 minutes (or 5 x 30 minutes in some countries) used in many countries round the world. They are the first government to try such an approach.

Karen Hancock and Margaret Sills (both over 60) completed the Cingle du Mont-Ventoux in July 2017.

So: what are my research methods? In line with current practice for economics PhDs, I am doing three pieces of work. The first is a policy analysis that critically evaluates the evidence for the implicit assumption that the 150 minutes a week message will increase physical activity and compares it with the evidence for the Japanese-style incremental framing. Second, I am developing econometric models of the physical activity of older people in more granular detail than much of the existing literature. That is to say, much of the existing econometric literature – influenced possibly by the current framing and priorities of public policy – tries to explain binary states like exercising/not exercising or meeting/not meeting the 150 minutes a week. I want to understand what predicts a wide range of levels and intensities of physical activity among over-50s. After all, there are quite a few Serpie veterans who manage to do enough to participate in marathons, ultramarathons and ‘Ironman’ events, and to do very well in them. But as far as Public Health England is concerned, only the first 150 minutes a week of moderate (i.e. brisk walking pace effort) or 75 minutes of vigorous exercise (walking uphill effort or more) count towards the health and fitness of the nation.  In other words, I want to understand the whole distribution of physical activity in the older population. The third element of my research is an intervention. I plan to test the impacts of incremental and current message framing on a group of older people to see which motivates greater increases in physical activity. For this, I am very grateful to have secured the blessing of our own ‘Iron Gran’ – Eddie Brocklesby – to work with members of her excellent ‘Silverfit’ charity that encourages older people to get fit and combat social isolation at the same time. The precise details of the intervention, and all the steps in gaining ethical approval, are still in the planning stage and will require further discussion with Eddie and Silverfit. Although participants in Silverfit are already motivated to exercise and results cannot necessarily be extrapolated to the sofa-bound, it would still add to what is already known about motivating people to exercise more and could provide an initial test of the idea of incremental-framing for setting exercise goals that could then be tested on other populations of older people.

So, it’s a lot of work, over a long period of time, much of it done alone, with many setbacks and challenges along the way. In that respect, it’s rather like training for a marathon – it involves long-term planning, problem-solving, learning from trial and error, leveraging your relationship capital when you can, compromising and adapting, and sustaining motivation when the prospect of success seems low. And building in appropriate recovery periods of course. But the point of this endeavour is not only the destination, it’s – to use an over-worked business cliché – the learning journey. For my journey, I have four supervisors to guide me, each with something different to add. Three – including my professorial lead supervisor – are economists; one is a sports psychologist. Between them, they have challenged everything I have written and done to try to help me think, write and research more like an academic, and less like the civil servant I was for 21 years of my life. They discourage complacency and encourage the necessary rigour to meet academic standards. And even when the criticism feels deeply uncomfortable, I keep coming back to my motivations for doing this: to achieve something of public value I can be proud of, refresh rusty skills and learn new ones, help older people feel better about their ability to exercise, and finally to die, after a very long and active life, with “Doctor” on my tombstone.

Karen Hancock started running competitively in Lowestoft in 1966 and began coaching in Edinburgh in 1996. After moving to London in 2001, Karen became a Serpie in 2003 and set up the Greenwich Hills session in 2004, 6 months before the first parkrun. As a result, she has only completed 35 parkruns. She now battles entropy and competes against her counterfactual, bone-idle self.

Grace Sim did the illustration for this article. Go and have a look round her website (link below).