Kevin J. Caldwell1, Steven J. Prior2, Meghan Kampmann1, Limin Zhao1, Sue McEvoy1, Brajesh K. Lal1
1University of Maryland School of Medicine, Baltimore, MD; 2Baltimore Veterans Affairs Geriatric Research, Education and Clinical Center, Baltimore, MD.
OBJECTIVES: Early postoperative ambulation prevents deep vein thrombosis (DVT) by enhancing lower extremity (LE) venous flow. Postoperative patients may require prolonged bed-rest. We tested if upper body exercise (UBE) increased LE venous flow, as a potential means for preventing DVT.
METHODS: Fifteen healthy volunteers (20-40 yrs) performed 4 low-intensity (5watts, 75 rpm) UBE protocols on an ergometer (single 30-sec and 3-min UBE bouts; and 3 repetitions of 30-sec and 3-min bouts with 1 min rest between bouts). External iliac vein volume flow was measured by ultrasound before and after UBE.
RESULTS: A single 30-sec bout of UBE increased LE volume flow by 39%; the increase was maintained up to 10 mins. post-exercise (p≤0.05). A single 3-min bout of UBE increased flow by 23% (p=0.05); flow was elevated (19%) for 5 mins (p=0.07). With 3 repetitions of the 30-sec UBE bouts, flow increased 57% after 1 bout and remained ≥34% higher after the remaining bouts for a total of >8.5 min of increased venous flow (p<0.05, figure). With repeated 3-min UBE, flow increased 32% after 1 bout, and remained ≥21% higher after the remaining bouts for an additional 5 mins (p<0.05).
CONCLUSIONS: We report a novel finding that UBE increases LE venous blood flow. The effect is consistent and durable. Three 30-sec bouts of low-intensity UBE was the most effective; eliciting a net increase of ~4.5L of LE venous flow over >8.5 minutes. UBE may be an alternative for prophylaxis of DVT in patients with restricted ambulation.
AUTHOR DISCLOSURES: K. J. Caldwell, Nothing to disclose; M. Kampmann, Nothing to disclose; B. K. Lal, Nothing to disclose; S. McEvoy, Nothing to disclose; S. J. Prior, Nothing to disclose; L. Zhao, Nothing to disclose.
Venous volume flow in the lower extremity after upper body exercise (3 bouts of 30-seconds ergometry).
Posted April 2012