Premium
Microvascular adaptation to short‐term resistance training of calf muscles is enhanced by vascular occlusion
Author(s) -
Brown Margaret D,
Evans Colin E,
Vance Steven M
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.5.a576-b
Subject(s) - isometric exercise , medicine , occlusion , vascular resistance , blood flow , vascular occlusion , cardiology , resistance training , leg press , blood flow restriction , plethysmograph , heel , hemodynamics , anatomy
Resistance training increases muscle strength and endurance but may require high intensity and long duration to enhance capillarity. Vascular occlusion during resistance training augments the strength and endurance gains, and this study investigated whether it also promotes microvascular adaptations. Nine healthy males performed short‐term 4 wk low intensity resistance training of the calf (4 sets of 50 heel raises 3 × per wk) under restricted (non‐dominant thigh cuff inflated to 150 mmHg, R) or unrestricted (dominant leg, UR) blood flow conditions. At baseline and post‐training, blood flow and calf filtration capacity (Kf) were assessed by strain gauge plethysmography, and calf muscle strength and fatigue respectively by maximal voluntary isometric contraction (MVC) and force decline during electrically‐evoked ischemic contractions in both legs. Kf increased by 26 ± 6 % in R leg (mean ± SEM, p<0.05 paired t‐test) and by 19 % in UR leg (NS) while blood flow was unchanged in both. MVC was 25% greater after training in R leg (p<0.05) and unchanged in UR. Fatigue, tested under ischemic conditions to detect metabolic adaptations, did not change after training in either leg. In 3 subjects, Kf was unchanged after 2 wk in R leg. Vascular occlusion thus promoted microcirculatory adaptation to resistance training, possibly through HIF‐1 regulated release of adenosine and VEGF.