The news and herald. (Winnsboro, S.C.) 1877-1900, 1883-06-26
An Onrsnlnn'B Stroke.

80 lar the action of the muscles cS-
sentially concerned in the performance
or the "StrOko" have been considered.
There are muscles concerned in the SUP
Elemental actions, viz: Those concern
Ell i'll the performance of respiration.
Seated at the stern Of an cight-oar one
notices that the frequency of the rcSpir-
atory act is directly proportional to the
quickncss of tho stroke. At an orli-
nary paddle tho reSpirations will be
about twcnty-eight per minute, as com
pared with the normal frequency, ciph-
teen to twenty, observed when the in
dIVldualS are taking ordinary walking
exercise. On quiciening the rcspira,
tlonS increase in frequency, but lose in
depth, and at racing pace often amount
10 thlrty-SlXand thirty-cight per minute.
Inspiration is effected in the act of
"coming forwau," the breath is held
during the stroke and there is IL sudden
expiration between the conclusion and
INC commencement Of fresh effect. The
full extension Of the arms forward of
course aids considerably in the cxpan-
Sion OF the chest; while the abdominal
muscles contract in order to steady the
contents OF that cavity and prevent
Their undue propulsion downward by
the descent of the diaphragm. Expira-
ton is effected chiefly by the rccoil of
these forces, the tension being height
encd by the breath beng held during
the stroke, and also by the action of
the internal intercoStal muscles, whose
action i'll cases of extraordinary rcSpira-
tory effort is about one-fourth moro
powerful than that Of the external in
tercoStalS, the muscles of inspiration.
Expiration, too, .as we have already
stated, is materially aided by bringing
the handle Of the oar to the chest. This.
too, is IL very important part of The
stroke, for the '>iinislln is nearly of
equal Importance as the "catch.1 If
contraction of tho biccpS commences
too soon, thon the stroke is not rowed
out; il deferred too late, the contrac-
ton is too vehement, and tho oar is
brought out with Il jerk. Willie the
oar is being rowcd to the chest the cl-
bows, by tho action Of the pcctOralis
magnus. should be brought well to the
sides. Violent contraction of the ilcx-
ors of the forearm, however, is not dc
slrcablc, having a tendency to bring
Tie oar out of the water with Il jerk. 4
great advantage, moreover, is gained
by bringing the arms sharply and close
~ TO the side at the end of the stroke;
1T aids The respiratory act. Expert
mcnts on the dead body clearly show
that when artificial resp iration is per-
formed according to Sylvestcr's method
more air can be forced out of the chest
when the arms are brought firmly and
closely in contact with the chest walls
than when the cxpcrimcntcr is simply
contcntcd with raising and depressing
them. The stroke is now at an end
and two subsidiary actions have to be
performed before it's rcc0mmcnccmcnt
tho drawing forward tho slide, and
execution of the feather. The former
is almost instantancously performed by
a vigorous and powerful contraction of
the hamstring muscles-musclcs which
before the introduction of the slide
wcre comparatively idle. The slide
therefore has introduced moro work
into the stroke, and, indeed, may also
be considered to be a third action.