More time spent standing rather than sitting could
improve your blood sugar, fats in the blood and
cholesterol levels, according to a new study
published in the European Heart Journal. The study
also shows that replacing time spent sitting with
time walking could have additional benefits for your
waistline and body mass index (BMI).
Researchers in Australia gave activity monitors to
782 men and women, aged 36-80 years, who were taking
part in the Australian Diabetes, Obesity and
Lifestyle Study. The monitors were capable of
determining, very accurately, how long each
participant spent sleeping, sitting or lying down,
standing and stepping (which includes walking and
running). After providing blood samples and
measurements of their blood pressure, height, weight
and waist circumference, participants each wore an
activity monitor on their thigh for 24 hours a day
over a seven-day period.
The researchers then used a statistical technique
called isotemporal analysis to estimate the
potential impact on health of reallocating time from
sitting to standing or stepping.
Dr Genevieve Healy, senior research fellow at the
School of Public Health, The University of
Queensland, Australia, who led the study, said: ”We
found that time spent standing rather than sitting
was significantly associated with lower levels of
blood sugar and blood fats.
Replacing sitting time with stepping was also
associated with a significant reduction in waistline
and BMI.
While the study cannot show that less time spent
sitting causes the improvements in these markers of
health, the associations it reveals are consistent
with what is known already about the benefits of a
non-sedentary lifestyle. More work is needed to
understand cause and effect.”
An extra two hours per day spent standing rather
than sitting was associated with approximately 2%
lower average fasting blood sugar levels and 11%
lower average triglycerides (fats in the blood).
Extra standing time was also associated with 0.06
mmol/L higher average levels of the “good” type of
cholesterol, HDL, and a 6% lower average total/HDL
cholesterol ratio, which indicates an improvement in
the total amount of HDL cholesterol in relation to
“bad” LDL cholesterol.
Replacing two hours a day of sitting time with
stepping was associated with an approximately 11%
lower average BMI and a 7.5cm smaller average waist
circumference.
In addition, average blood sugar levels fell by
approximately 11% and average triglycerides by 14%
for every two hours spent walking rather than
sitting, while HDL cholesterol was 0.10 mmol/L
higher.
There was no significant effect on BMI or waistline
of replacing sitting time with standing.
“However, it is important to say that not all
sitting is bad; but if people can incorporate
alternatives to sitting wherever possible, it may
benefit their heart and metabolic health. Our
message is to ‘Stand Up, Sit Less, Move More’.”
She said the study had also produced evidence of how
common standing is during the waking day.
“Standing takes up nearly a third of waking hours,
and among this group of participants who could
choose when they sat, stood or walked, the standing
had health benefits. Notably, we did not measure
upper body movement, so someone could be standing up
doing the dishes, which involves some extra physical
activity.”
While the benefits to health of walking have been
well established, until now the potential benefits
(or harms) of replacing sitting with standing have
been less well understood.
The study is one of the first to look at the
estimated associations between replacing time in one
activity with another and its effect on markers of
health, such as blood pressure, blood sugar and
cholesterol levels, BMI and waist circumference.
The researchers say more, larger studies are needed
to confirm their findings and they hope to follow up
the study participants for longer, as well as
studying participants from a wider age range.
In an accompanying editorial, Professor Francisco
Lopez-Jimenez (MD, MSc) of the Mayo Clinic and Mayo
College of Medicine (Minnesota, USA) writes that the
study “provides an important addition to the wealth
of scientific evidence highlighting the importance
of avoiding sedentary behaviour”. He writes that
“the fight against sedentary behaviour cannot be won
based only on the promotion of regular exercise” and
that while exercise should continue to be
recommended, it is important to promote
non-sedentary behaviour in everyday life. “A person
walking while at work for two hours, standing for
another four hours, and performing some daily chores
at home for another hour will burn more calories
than jogging or running for 60 minutes.”
He also points out that sedentary behaviour and
environments that promote it are “seen as a sign of
progress and economic power”. For instance, poorer
people are more likely to bike or walk than drive a
car, and standing tickets to watch a football match
or an opera will be cheaper than seated tickets.
He concludes: “The unintended consequences of modern
life promoting sedentary behaviours can be reversed.
Health care providers, policy makers and people in
general need to stand up for this. Literally.”
For more information
“Replacing sitting by standing or stepping:
associations with cardio-metabolic risk biomarkers”,
by Genevieve N. Healy et al.
European Heart Journal.
doi:10.1093/eurheartj/ehv308
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