It is difficult to explain how massage reduces DOMS, because
no authors have yet described the effects of massage on
cellular events or pathophysiologic changes in the muscle or
connective tissue after eccentric exercise. Increasing blood
flow appears to be a major consequence of massage.8,10 Increases
in blood and lymph flow may enhance removal of pain
substrates that start to accumulate in the injured area, reducing
edema. We found smaller increases in upper arm circumference
3 and 4 days postexercise for the massage condition compared
with the control (see Table 2). This may explain why
DOMS was attenuated by massage, if indeed edema is associated
with muscle soreness. Smith et al13 showed that circulating
neutrophil levels were elevated from baseline for several
hours after massage compared with the control condition and
speculated that this was due to a reduced emigration of neutrophils
into tissue spaces. However, no authors have yet
shown that massage can decrease the migration of neutrophils
or other leukocytes (ie, macrophages) to the injured sites. Massage
to sore muscles could increase discharge from other lowthreshold
sensory fibers and block pain sensation temporarily1;
however, the massage in our study was performed before
soreness occurred.