Low‐load Resistance Exercise with Blood Flow Restriction Changes Hypoxia‐Induced Genes Expression

Abstract

PURPOSETo investigate the effects of low‐load exercise with blood flow restriction on expression of genes related to hypoxia.METHODSTwenty‐four male (mean ± SD: age 21.3 ± 1.9 years, height 1.74 ± 0.8 m, body mass 73 ± 1.8 kg) were divided into three groups: low‐load exercise (LL, n=9), low‐load exercise with blood flow restriction (LL‐BFR, n=8), and high‐load exercise (HL, n=7). For LL‐BFR group a pneumatic cuff was placed on the proximal portion of the thigh and inflated at 80% of the resting arterial occlusion pressure. All subjects performed bilateral knee extension, 2x/week, during 8 weeks. LL and LL‐BFR groups performed 3–4 sets of 15 reps at 20% 1RM whereas HL performed 3–4 sets of 8–10 reps at 80% 1RM with 60s rest interval between sets. Regulated in development and DNA damage response 1 (REDD1), hypoxia‐inducible factor‐1‐alpha (HIF‐1‐alpha), vascular endothelial growth factor (VEGF), and neuronal nitric oxide synthase (nNOS) mRNA gene expression were assessed before and after training. Mixed model for repeated measures was performed for each dependent variable, and statistical significance was set at p≤ 0.05.RESULTSREDD1 expression decreased in all groups from pre‐ to post‐training (p<.0001), and significantly lower REDD1 expression was found in both LL‐BFR and HL groups when compared with LL group at post‐training (p<0.05) [Figure 1A). HIF‐1α mRNA expression increased in all groups from pre‐ to post‐training (p<.0001), and significantly greater values were observed in LL‐BFR and HL groups when compared with LL group at post‐training (p<.0001) [Figure 1B]. VEGF mRNA expression increased in both LL‐BFR and HL groups from pre‐ to post‐training (p<.0001); however, only LL‐BFR showed greater expression than LL group at post‐training (p=0.001) [Figure 1C). nNOS mRNA expression increased in all groups from preto post‐training (p<.0001), and greater expression values were observed in LL‐BFR when compared with both LL and HL groups at post‐training (p<.0001) [Figure 1D].CONCLUSIONLow‐load resistance exercise with blood flow restriction induced changes in selected genes expression related to hypoxia following training. These results may contribute with the skeletal muscle hypertrophy responses and increased muscular angiogenesis after training period.Support or Funding InformationThis study was not supported by any fundingThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.