Concomitant aerobic- and hypertrophy-related skeletal muscle cell signaling following blood flow-restricted walking
Résumé
Objective
This study is aimed to examine the acute responses to a blood flow restriction (BFR) low-intensity aerobic exercise, compared with a similar exercise without BFR, on several aerobic- and hypertrophy-related proteins expression and hormonal responses.
Methods
On two different occasions, five healthy untrained male subjects were required to perform (i) a BFR low-intensity aerobic exercise consisting of 5 sets of 2-min bouts of walking at an exercise intensity of 63–65% HRmax (equivalent to 40% of VO2max), interspersed by 1-min rest; and (ii) similar exercise bouts without BFR (Ctrl). For each condition, venous blood samples were collected at pre- (baseline), immediately and 2-h post-exercise. Baseline and 3-h post-exercise muscle biopsy samples (vastus lateralis) were also performed for protein expression analysis.
Results
HIF-1α, PGC-1α, and VEGF proteins content were significantly higher (P < 0.05) at 3-h post-exercise in BFR compared with baseline values. In reference to baseline, phosphorylation of Akt also increased significantly (P < 0.05) following BFR, and in a greater extent (P < 0.05) than following Ctrl. IGF-1 concentration significantly increased (P = 0.001) immediately following BFR exercise than baseline values and serum GH showed a significant increase (P = 0.046) compared with Ctrl.
Conclusion
The addition of blood flow restriction during walking exercise initiate a concomitant cell signaling pathways regulating mitochondrial biogenesis, angiogenesis, and skeletal muscle protein expression.
This study is aimed to examine the acute responses to a blood flow restriction (BFR) low-intensity aerobic exercise, compared with a similar exercise without BFR, on several aerobic- and hypertrophy-related proteins expression and hormonal responses.
Methods
On two different occasions, five healthy untrained male subjects were required to perform (i) a BFR low-intensity aerobic exercise consisting of 5 sets of 2-min bouts of walking at an exercise intensity of 63–65% HRmax (equivalent to 40% of VO2max), interspersed by 1-min rest; and (ii) similar exercise bouts without BFR (Ctrl). For each condition, venous blood samples were collected at pre- (baseline), immediately and 2-h post-exercise. Baseline and 3-h post-exercise muscle biopsy samples (vastus lateralis) were also performed for protein expression analysis.
Results
HIF-1α, PGC-1α, and VEGF proteins content were significantly higher (P < 0.05) at 3-h post-exercise in BFR compared with baseline values. In reference to baseline, phosphorylation of Akt also increased significantly (P < 0.05) following BFR, and in a greater extent (P < 0.05) than following Ctrl. IGF-1 concentration significantly increased (P = 0.001) immediately following BFR exercise than baseline values and serum GH showed a significant increase (P = 0.046) compared with Ctrl.
Conclusion
The addition of blood flow restriction during walking exercise initiate a concomitant cell signaling pathways regulating mitochondrial biogenesis, angiogenesis, and skeletal muscle protein expression.