If you, like most adults, are a desk-dweller throughout the week, it is unfortunate that
you are limited to such a place of work. However, what is not unfortunate is that you do not
need to sit stagnant for the entirety of any given day. Fidget in your chair constantly. Squirm
around. Change how your body is positioned. It will do a lot more for you than you’d think.
After all, it is a form of Physical Activity.
Physical activity is loosely defined but it can be as simple as any movement produced by
skeletal muscles, which results in energy expenditure. It is not just the intense workout, long
job, or yoga session that counts towards Physical Activity, and thus energy expenditure. In fact,
hardly any of the energy we humans expend in a given day is from intentional, purposeful
exercise. The majority of the Physical Activity we participate in on a daily basis is non-exercise.
Things like walking to and from the bus stop, taking the stairs, standing, talking, and the list
To put it all into simple terms, every movement we produce which is drive by muscular
contraction, results in energy expenditure. This is not a new discovery by any means, but it is
something that can help us break up Physical Activity into two categories: Exercise Activity
Thermogenesis (EAT), and Non-Exercise Activity Thermogenesis (NEAT). It may sound confusing,
but we actually expend far more energy per day through NEAT than we do through EAT. If you
are working out or training, chances are you are not spending more than two hours in a day
with it. However, with NEAT, any movements or activities of basic daily living you do for the
entire rest of the day apart from training, is expending energy. So it is easy to see the ratio of
time spent in each Physical Activity category each day, and how important the implications of
NEAT may actually be in regulating energy balance in humans.
Regardless of how crazy it sounds, there is a huge field of research with a focus on
understanding just how much one’s total daily energy expenditure is impacted by non-exercise
movements performed throughout the day – like fidgeting and squirming at your
desk/workstation. To avoid delving too far into the science behind how participating in NEAT
can directly impact one’s total daily energy expenditure, and chronic energy balance, just think
about the organ of the human body which initiates and controls movement, Skeletal muscle of
course. As I said earlier, anything movement you make during any activity results in energy
expenditure because of muscular contraction. Why does muscular contraction, even just while
fidgeting at a desk, count towards this expenditure? Your muscles do not work for free. There is
a cost to perform repeated contractions throughout the day, and the currency is in the form of
what is called ATP. Think of ATP as the money needed to buy movement, through muscular
contractions. There are several other molecules and proteins within skeletal muscle which can
regulate how efficient or inefficient your energy expenditure is, by using ATP (by spending
money). One of these proteins of particular importance, is called SERCA. SERCA uses ATP in
order to move Calcium into a closed space of the cell called the Sarcoplasmic Reticulum, during
muscle relaxation. That’s right, it doesn’t just cost money (ATP) to contract, but also to relax.
So, the more you contract AND relax your muscle throughout the day, the more ATP you are
spending, and therefore the more energy you are expending.
To bring this all back to EAT vs NEAT, regardless of the modality or intensity of Physical Activity,
you are still expending energy with any kind of Physical Activity. And because NEAT is
participated in for a much larger portion of the day, researching and understanding how
proteins such as SERCA can regulate energy expenditure is a hot topic, with important
implications in the maintenance of energy balance (energy intake vs energy expenditure).
Fidget, squirm, switch positions, stand up, sit back down. Your body is undergoing energy
expending (ATP spending) processes more than you might think while at the office work