It’s About Movement, Not Calories cont’d 25
Yes, we were born to run, but I argue strongly that
we were not born to run 42 miles a week year in
and year out as we accumulate marathon finisher
medals on the wall. Let’s look at our own evolu-
tion. Our hunter-gatherer ancestors engaged in
extensive low level of aerobic activity every day:
walking, foraging, migrating, hunting and gather-
ing. I guarantee you they didn’t regularly ramp
their heart rates up to 80 percent of max for over
an hour a day like so many of us do now. Even
when the concept of organized or persistence
hunting came along, it was something they did as
occasionally necessary for survival and certainly
not on a daily basis. It would appear that our
hunter-gatherer ancestors relied more on supe-
rior tracking ability (using highly evolved and ex-
ceptionally large brains) and walk/jogging (using
superior fat-burning systems), rather than on ac-
tually running at race pace to chase down their
prey. Evolution has driven our genes to expect a
fair amount low level activity, but only infrequent
high-level endurance work.
The health impact of low level activity is impres-
sive to say the least. Specific studies have found
that it reduces the risk of metabolic syndrome,
breast cancer, and death from cardiovascular dis-
ease. It also appears to reduce the risk of vascular
dementia. But the kicker is this: low level aerobic
activity, research suggests, can decrease overall
systemic inflammation and the risk for the vast
array of degenerative diseases that plague our
modern society. Skeletal muscle fibers, research-
ers have found, act as “an endocrine organ.”
Working the muscle fibers, it appears, stimulates
the production of Interleukin-6, an anti-inflamma-
tory cytokine, which in turn signals and benefits
other organs. Don’t you love this? On the lighter
note, low level aerobic activity also decreases the
incidence of colds.Want more? Turns out there are mental health ben-
efits as well. Moderate exercise has been shown
to improve the mood and well-being of those with
chronic depression. But for all of us, low to moder-
ate level aerobic activity can elevate our mood a
good two to four hours after exercise. (And that’s
just after 20 minutes or so of activity.) We’ve all felt
this one, haven’t we? Letting go of the stress on a
solitary hike or evening walk with a friend?