The effect of aerobic conditioning on venous pooling in the foot.
Nineteen fit college-age men were studied using foot (mid-arch) mercury-in-silastic strain gauge plethysmography before and after an 8-wk aerobic conditioning (running) program. Foot volume changes were followed through two maneuvers: a 15-s Trendelenburg procedure (passive leg elevation with subsequent relaxation in the dependent position) and a 15-s dynamic dorsi-flexion/plantar flexion exercise and subsequent relaxation. The conditioning regimen consisted of running 40 min, 3 d.wk-1 and resulted in a 10% (P less than 0.01) increase in VO2max. Following this regimen, subjects exhibited an increased blood volume drainage during the Trendelenburg procedure (mean delta VT = 3.3 ml.100 ml-1 pre-training, 3.8 ml.100 ml-1 post-training, P less than 0.05), but no significant change in delta VE (2.7 ml.100 ml-1 for all subjects). Muscle pump efficacy, defined as the ratio between delta VE and delta VT, did not change (64%). These data suggest that increased aerobic power via weight-bearing exercise training results in an increased foot venous pooling, but does not affect relative muscle pump function. This apparent increase in vascular pooling may be a physical response to the hypervolemia induced by endurance training, aiding in maintaining the constancy of vascular pressures.
Kenney
W L
WL
Laboratory for Human Performance Research, Pennsylvania State University, University Park 16802.
Armstrong
C G
CG
D000293:Adolescent; D000328:Adult; D001810:Blood Volume; D005528:Foot / Q000098:blood supply*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D010806:Physical Education and Training; D010991:Plethysmography; D012420:Running; D014680:Veins / Q000502:physiology