Low intensity resistance exercise training with blood flow restriction: insight into cardiovascular function, and skeletal muscle hypertrophy in humans

Abstract

Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strength and mass may be contraindicated for some at risk populations, such as diseased populations and the elderly. Therefore, an alternative exercise modality is required. Recently, blood flow restriction (BFR) with low intensity resistance exercise (LIRE) has been used for such special populations to improve their function and exercise capacity. Although BFR+LIRE has been intensively studied for a decade, a comprehensive review detailing the effects of BFR+LIRE on both skeletal muscle and vascular function is not available. Therefore, the purpose of this review is to discuss previous studies documenting the effects of BFR+LIRE on hormonal and transcriptional factors in muscle hypertrophy and vascular function, including changes in hemodynamics, and endothelial function.

Keywords: Blood flow restriction; Low intensity resistance exercise; Muscular hypertrophy; Vascular function.

Fig. 1. The impacts of BFR+LIRE on skeletal muscle and vasculature. Schematic of the impacts of BFR+LIRE on skeletal muscle (hormonal, and transcriptional factors) and vasculature (Endothelial, autonomic, hemodynamic function). GH, growth hormone; IGFs, insulin like growth factors; mTOR, mRNA in mammalan target of rapamycin; S6K1, ribosomal s6 kinase 1; PI3K, phosphoinositide 3- kinase; Akt, protein kinase B; VEGF, hemvascular endothelial growth factor; FMD, flow mediated dilation; ET-1, endothelin 1; (↑), increase; (↓), decrease; (-), no change; (?), inconsistent data.