The aim of this study was to compare the effect of low-load resistance exercise (LLRE) with continuous and intermittent blood flow restriction (BFR) on the creatine kinase (CK), lactate dehydrogenase (LDH), protein carbonyl (PC), thiobarbituric acid-reactive substance (TBARS) and uric acid (UA) levels in military men. The study included 10 recreationally trained men aged 19 ± 0.82 years who underwent the following experimental protocols in random order on separate days (72-96 h): 4 LLRE sessions at a 20% 1RM (one-repetition maximum [1RM]) with continuous BFR (LLRE + CBFR); 4 LLRE sessions at 20% 1RM with intermittent BFR (LLRE + IBFR) and 4 high-intensity resistance exercise (HIRE) sessions at 80% 1RM. The CK and LDH (markers of muscle damage) levels were measured before exercise (BE), 24 h post-exercise and 48 h post-exercise, and the PC, TBARS and UA (markers of oxidative stress) levels were measured BE and immediately after each exercise session. There was a significant increase in CK in the HIRE 24 post-exercise samples compared with the LLRE + CBFR and LLRE + IBFR (P = 0.035, P = 0.036, respectively), as well as between HIRE 48 post-exercise and LLRE + CBFR (P = 0.049). Additionally, there was a significant increase in CK in the LLRE + CBFR samples BE and immediately after each exercise (Δ = 21.9%) and in the HIRE samples BE and immediately after each exercise, BE and 24 post-exercise, and BE and 48 post-exercise (Δ values of 35%, 177.6%, and 177.6%, respectively). However, there were no significant changes in LDH, PC, TBARS, and UA between the protocols (P > 0.05). Therefore, a physical exercise session with continuous or intermittent BFR did not promote muscle damage; moreover, neither protocol seemed to affect the oxidative stress markers.

This study compared the acute effects of low-intensity resistance exercise (RE) sessions for the upper limb with continuous and intermittent blood flow restriction (BFR) and high-intensity RE with no BFR on lactate, heart rate, double product (DP; heart rate times systolic blood pressure), and perceived exertion (RPE). Ten recreationally trained men (1-5 years strength training; age mean = 19 ± 0.82 years) performed three experimental protocols in random order: (a) low-intensity RE at 20% one-repetition maximum (1RM) with intermittent BFR (LI + IBFR), (b) low-intensity RE at 20% 1RM with continuous BFR (LI + CBFR), and (c) high-intensity RE at 80% 1RM. The three RE protocols increased lactate and DP at the end of the session ( p < .05) and increased heart rate at the end of each exercise ( p < .05). However, greater local and general RPE was observed in the high-intensity protocol compared with LI + IBFR and LI + CBFR in the lat pull-down, triceps curl, and biceps curl exercises ( p < .05). A greater percentage change in DP and lactate was observed for continuous BFR compared with intermittent BFR; however, RPE was lower for intermittent BFR. In conclusion, intermittent BFR appears to be an excellent option for physical training because it did not differ significantly from continuous BFR in any variable and promoted a lower percentage change in DP and RPE.

This study systematically reviewed the available scientific evidence on the changes promoted by low-intensity (LI) resistance training (RT) combined with blood flow restriction (BFR) on blood pressure (BP), heart rate (HR) and rate-pressure product (RPP). Searches were performed in databases (PubMed, Web of Science , Scopus and Google Scholar), for the period from January 1990 to May 2015. The study analysis was conducted through a critical review of contents. Of the 1 112 articles identified, 1 091 were excluded and 21 met the selection criteria, including 16 articles evaluating BP, 19 articles evaluating HR and four articles evaluating RPP. Divergent results were found when comparing the LI protocols with BFR versus LI versus high intensity (HI) on BP, HR and RPP. The evidence shows that the protocols using continuous BFR following a LIRT session apparently raise HR, BP and RPP compared with LI protocols without BFR, although increases significantly in BP seem to exist between the HI protocols when compared to LI protocols. Haemodynamic changes (HR, SBP, DBP, MBP, RPP) promoted by LIRT with BFR do not seem to differ between ages and body segments (upper or lower), although they are apparently affected by the width of the cuff and are higher with continuous BFR. However, these changes are within the normal range, rendering this method safe and feasible for special populations.