Impact of eight weeks of repeated ischaemic preconditioning on brachial artery and cutaneous microcirculatory function in healthy males

Background: Ischaemic preconditioning has well-established cardiac and vascular protective effects. Short interventions (one week) of daily ischaemic preconditioning episodes improve conduit and microcirculatory function. This study examined whether a longer (eight wee1ks) and less frequent (three per week) protocol of repeated ischaemic preconditioning improves vascular function. 

Methods: Eighteen males were randomly allocated to either ischaemic preconditioning (22.4±2.3 years, 23.7±3.1 kg/m²) or a control intervention (26.0±4.8 years, 26.4±1.9 kg/m²). Brachial artery endothelial-dependent (FMD), forearm cutaneous microvascular function and cardiorespiratory fitness were assessed at zero, two and eight weeks. 

Results: A greater improvement in FMD was evident following ischaemic preconditioning training compared with control at weeks 2 (2.24% (0.40, 4.08); p=0.02) and 8 (1.11% (0.13, 2.10); p=0.03). Repeated ischaemic preconditioning did not change cutaneous microcirculatory function or fitness. 

Conclusions: These data indicate that a feasible and practical protocol of regular ischaemic preconditioning episodes improves endothelial function in healthy individuals within two weeks, and these effects persist following repeated ischaemic preconditioning for eight weeks.