M. Yamamoto et al., Static exercise-induced increase in blood pressure in individuals with cervical spinal cord injury, ARCH PHYS M, 80(3), 1999, pp. 288-293
Objective: To compare the presser response to static exercise in subjects w
ith cervical spinal cord injury (SCI) at the C6 to C8 level with that in ab
le-bodied control subjects. In these SCI subjects, the descending supraspin
al sympathetic neurons and afferent pathways from the contracting muscles t
o peripheral vessels via the medullary cardiovascular center are damaged.
Design: Mean arterial blood pressure, heart rate, and plasma concentrations
of norepinephrine, epinephrine, renin activity, vasopressin, aldosterone,
and human atrial natriuretic peptide were measured during a 2-minute period
of sustained contraction of elbow flexor group muscle in 7 SCI subjects an
d 7 age-marched able-bodied control subjects.
Results: Static exercise resulted in a significant increase in mean blood p
ressure (p < .05) in both SCI subjects (preexercise, 74.7 +/- 2.2 mmHg; sta
tic exercise, 81.9 +/- 4.1 mmHg) and control subjects (pre-exercise, 101.0
+/- 4.2 mmHg; static exercise, 117.0 +/- 4.9 mmHg). In SCI subjects, there
was no change in heart rate during exercise, whereas in control subjects he
art rate increased during exercise (p < .05) (pre-exercise, 68.7 +/- 3.8 be
ats/min; static exercise, 76.0 +/- 3.1 beats/min). There were no significan
t changes in the hormone levels in the SCI subjects throughout the experime
nt.
Conclusion: The significant increase in mean blood pressure observed in the
present study indicates the presence of peripheral control from muscle rec
eptors and evoked presser response during static exercise in SCI subjects.
(C) 1999 by the American Congress of Rehabilitation Medicine and the Americ
an Academy of Physical Medicine and Rehabilitation.