Flex_USA_JulyAugust_2017_2

LIFT
LAB TO GYM
BY BRYAN HAYCOCK PH.DC
LIGHTEN
UP, DUDE!
WHY GOING TOO HEAVY COULD
BE BAD FOR A BIGGER CHEST
HYPOTHESIS
The bench press is
one of the most popular
gym exercises. As a
compound exercise, it
brings multiple muscle
groups—including the
delts and triceps—into
play as prime movers
and stabilizers that
must work together
to balance, direct
movement, and generate
force. It’s easy to think
that the activity of the
primary muscle groups
involved would simply
increase as the load
increases. However,
recent research calls
this into question.
RESEARCH
A study published in the
Journal of Strength &
Conditioning Research
examined the impact
that increasing loads
has on the activation
and contributions of the
chest, front delt, triceps,
and lats during the
bench press. Subjects
performed consecutive
sets of a single repetition
of a bench press with
an increasing load
(about 70, 80, 90, and
100% of their 1RM) while
electromyography (EMG)
readings were taken
from the aforementioned
muscle groups.
FINDINGS
To the researcher’s
surprise, the chest,
which is normally the
prime mover, changes
to a “supportive” prime
mover when the load
reaches maximum. In
other words, as the
weight increases from
80 to 90 to 100% of
the subject’s 1RM, the
chest’s contribution
gives way to the front
delts and triceps,
which essentially take
over as primer movers.
CONCLUSION
As the weight used
during bench press
increases from about
70 to 100% 1RM, the
shoulders and triceps
become the prime
movers of the exercise.
APPLICATION
The activation of the
chest peaked before
reaching 100% 1RM.
This tells us that the
most efficient way to
train the chest is not
with maximum loads.
To put the focus on
building the chest,
75 to 85% 1RM is
best. The authors of
the study also confirm
that to protect the
shoulders from injury
while maintaining the
effectiveness of the
exercise, the bar should
be brought down to the
nipple line, and the hand
placement should be
within 1.5 times the
biacromial width, or the
width from the far end
of the right collarbone to
the far end of the left.
PAVEL YTHJALL
72 FLEX | JULY/AUG ’17