Modification of vascular function after handgrip exercise training in 73- to 90-yr-old men.
OBJECTIVE
To examine the influence of a unilateral exercise training protocol on brachial artery reactivity (BAR) in 12 men (aged 81 +/- 5 yr).


METHODS
Brachial artery diameters and blood flow parameters were assessed, in both arms, using high-resolution ultrasonography, before and after 5 min of forearm occlusion, before and at the end of each week of a 4-wk training program. Training consisted of a unilateral handgrip training protocol (nondominant arm) at 60% of maximal voluntary handgrip strength, performed for 4 wk, 4 d x wk(-1), 20 min per session, and a cadence of one contraction per 4 s.


RESULTS
After training, handgrip strength increased 6.2% (baseline = 32.4 +/- 7.0 kg vs week 4 = 34.4 +/- 6.7 kg) in the trained arm only but failed to reach statistical significance (P = 0.10). No statistical changes were observed for blood pressure or resting HR. In contrast, BAR increased 45% (Pre = 2.9% vs Post = 4.1%, P = 0.05) in the trained arm only. Improvements in BAR were observed after the second week of training, without significant changes in the main vasodilatory trigger, defined as the relevant shear stimulus after forearm occlusion (P > 0.05).


CONCLUSIONS
These data indicate that a localized short-term exercise program results in significant improvements in vascular function in the trained arm of elderly men compared with the control arm. Furthermore, the findings indicate a statistically significant increase in BAR at the end of the second week of training, despite a similar trigger for dilation versus before training.
Dobrosielski
Devon A
DA
Wake Forest University, Winston-Salem, NC, USA.
Greenway
Frank L
FL
Welsh
David A
DA
Jazwinski
S Michal
SM
Welsch
Michael A
MA
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy; D018737:Hand Strength / Q000502:physiology*; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D053581:Muscle Strength Dynamometer; D010101:Oxygen Consumption; D010809:Physical Fitness / Q000502:physiology*; D015397:Program Evaluation; D012039:Regional Blood Flow; D013223:Statistics as Topic; D013997:Time Factors; D014463:Ultrasonography; D014664:Vasodilation