Many of us put our feet up over Christmas, but just two weeks of “taking it easy” could damage our health.
Scientists from the University of Liverpool asked 47 volunteers, 21 of which were elderly, to walk around 1,500 steps a day for a fortnight.
Compared to their usual minimum of 10,000 steps, this reduced activity caused the participants to gain a significant amount of weight, particularly around their waist.
Two weeks of “lazying around” also reduced their bone density and caused fat to accumulate in their muscles, weakening them.
“The severe impact of short-term inactivity on our health is hugely important to communicate to people,” study author Juliette Norman said.
“If the gym is hard to get to, people should be encouraged to just meet 10,000 steps as even this can guard against reductions in muscle and bone health, as well as maintaining healthy levels of body fat.”
A brisk 10 minute walk every day can help build stamina, burn calories and boost heart health, according to the NHS.
Studies that look at inactivity tend to be extreme, like bedrest, which is not relevant for most healthy people, the scientists claim.
To uncover the effects of cutting back on exercise for a short while, the volunteers were asked to severely reduce their step count on four days a week.
While just 1,500 steps a day may sound extreme, this could apply to people who are ill, unable to get out due to extreme weather “or even just over the festive period”, the scientists claim.
Results reveal the loss to bone mass and muscle strength - and gain in fat - was the same between all the participants.
The elderly volunteers, however, had less muscle and more fat to start with, and are therefore expected to be worse affected.
The full findings were presented at The Physiological Society’s Future Physiology conference in Aberdeen.
The outcomes are concerning given the ageing population, the scientists said.
In 2016, nearly one in five (18%) members of the UK population were 65 and over, while 2.4% were 85 or over, according to the Office for National Statistics.
In the US, the number of Americans aged 65 or over is expected to nearly double from 52 million in 2018 to 95 million by 2060, Population Reference Bureau data shows.
The elderly participants were also worse off when it came to their cardiorespiratory fitness (CRF) and mitochondrial function.
CRF refers to the efficiency of which oxygen is supplied to muscles during sustained intense exercise.
Influenced by heart and lung health, those with a low CRF may be more at risk of disease at a younger age, the scientists said.
Mitochondria are the “energy powerhouses” of cells, driving muscle and metabolic health.
Declines in CRF and mitochondrial function may be what triggers loss of muscle function, reduced bone mass and gains in fat.
“This highlights the importance of maintaining levels of physical activity throughout the lifespan,” the scientists wrote.