carnegieXchange: School of Sport

Plain lazy or efficiently evolved? The challenge of behaviour change

Most of us have a desire, or intention, to change our behaviour. Being more active, eating fewer biscuits and drinking less beer might be highly compelling for our happiness, or indeed vital for our health.

Published on 07 Mar 2018
Evolution of Man


Motivation for improving health is particularly evident in January; often featuring in New Years’ resolutions. However, for many people this doesn’t materialise.

The intention-behaviour gap is a phenomenon psychologists have examined for years and there are continued efforts to support people turning their intentions into actual behaviours. Even when achieved, changes are rarely maintained, often fostering self-criticism. Negative self-perceptions such as laziness, can compound the problem to create a vicious circle of self-fulfilling prophecy.

Understanding why positive behaviour change is such a challenge is imperative for developing effective solutions. Perhaps negative connotations are not warranted; there’s a good reason why homo sapiens are the dominant species on the planet. We have evolved to satisfy our basic drives whilst taking “the path of least resistance”, i.e. to consume and store maximal energy and to move as little as possible. This enabled our hunter-gatherer ancestors to not simply survive, but thrive.

The hunter-gatherer life required effort. Over 10,000 years, we have engineered effort out of daily life – in the developed world, daily endeavours far surpass solely ensuring survival. We, as individuals and collectively, strive to reduce physical activity whilst exposure to high-fat and high-sugar foods has increased. These foodstuffs were the prize that hunter-gatherers sought, and once found, were probably consumed in as much quantity as possible. Fruits and nuts were precious and neurochemical reward responses evoked on consumption provided reinforcement. Thus, gluttony was encouraged, and gluttonous consumption could have been crucial for survival.

Convenience or con?

Contemporarily, an over-abundance of these previously rare energy sources of fat and sugar are thrust at us at every opportunity. We receive them without moving from our homes and cars, to save ourselves hunting, preparing and cooking it. Consider a smoothie. Annihilate the satiating fibre and the need to chew, and the volume of fruit consumed within a few mouthfuls is staggering compared with the organic version of gathering. Alongside escalators, TV remotes and prolific bus stops, the path of least resistance is paved and unconsciously appealing. Resultantly, striving to achieve healthy behaviours is problematic for our hunter-gatherer brains: environmental changes occur far quicker than evolutionary adaptations.

Our environment tempts us to take the path of least resistance, and its influence is evidenced by the negative correlation between socio-economic status and many health indicators. The number of fast food establishments in an area increases with deprivation, alongside fewer fresh food providers (food deserts) and physical activity opportunities. Further, greater chronic stress elicits increased cortisol release; amplifying the drive for, and reward from, consuming high fat and sugar - comfort eating is not simply an emotional response. Cortisol also causes additional fat storage abdominally.

Individually, we cannot dictate our environment, nor our efficiency at converting energy consumed into body fat (unlike metabolism, which can be manipulated). Phenotype dictates body fat storage: either spendthrift or thrifty. The latter is beneficial during times of hardship and potentially frustrating in modern times.

Rather than feeling disheartened, reflecting on the bigger picture - in which we are mere specks - should assist in the challenge of behaviour change. Knowledge is powerful and reassuring – working with evolution, not against it, illuminates ways in which behaviour change can be achieved and maintained, all without setting foot in a gym or engaging in a diet. Start with small steps, such as parking further away from your destination or taking the stairs instead of the lift.

Dr Stuart Flint

Dr Stuart Flint is a psychologist with a specific interest in the psychosocial effects of obesity; in particular obesity stigmatisation and discrimination, conscious and unconscious attitudes, body image, attitude and behaviour change and factors that influence exercise participation. Stuart previsouly lectured at Leeds Beckett.

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