Gabriel Rodrigues Neto

Hypotensive effects of resistance exercises with blood flow restriction.

Abstract Neto, GR, Sousa, MSC, Costa, PB, Salles, BF, Novaes, GS, and Novaes, JS. Hypotensive effects of resistance exercises with blood flow restriction. J Strength Cond Res 29(4): 1064–1070, 2015—The effects of low-intensity resistance exercise (RE) combined with blood flow restriction (BFR) on blood pressure (BP) are an important factor to be considered because of the acute responses imposed by training. The aim of this study was to compare the hypotensive effect of RE performed with and without BFR in normotensive young subjects. After 1 repetition maximum (1RM) tests, 24 men (21.79 ± 3.21 years; 1.72 ± 0.06 m; 69.49 ± 9.80 kg) performed the following 4 experimental protocols in a randomized order: (a) high-intensity RE at 80% of 1RM (HI), (b) low-intensity RE at 20% of 1RM (LI), (c) low-intensity RE at 20% of 1RM combined with partial BFR (LI + BFR), and (d) control. Analysis of systolic blood pressure (SBP) and diastolic blood pressure (DBP) was conducted over a 60-minute period. The 3 RE protocols resulted in hypotensive SBP (HI = −3.8%, LI = −3.3%, LI + BFR = −5.5%) responses during the 60 minutes (p ⩽ 0.05). The LI + BFR protocol promoted hypotensive (−11.5%) responses in DBP during the 60 minutes (p ⩽ 0.05), and both the HI and LI + BFR protocols resulted in mean blood pressure (MBP) hypotension between 30 (−7.0%, −7.7%) and 60 minutes (−3.6%, −8.8%), respectively. In conclusion, postexercise hypotension may occur after all 3 exercise protocols with greater reductions in SBP after HI and LI + BFR, in DBP after LI + BFR, and in MBP after HI and LI + BFR protocols.

Acute resistance exercise with blood flow restriction effects on heart rate, double product, oxygen saturation and perceived exertion

The aim of this study was to compare the acute effect of resistance exercise (RE) with and without blood flow restriction (BFR) on heart rate (HR), double product (DP), oxygen saturation (SpO2) and rating of perceived exertion (RPE). Twenty‐four men (21·79 ± 3·21 years) performed three experimental protocols in a random order (crossover): (i) high‐intensity RE at 80% of 1RM (HI), (ii) low‐intensity RE at 20% of 1RM (LI) and (iii) low‐intensity RE at 20% of 1RM combined with partial blood flow restriction (LI+BFR). HR, blood pressure, SpO2 and RPE were assessed. The data were analysed using repeated measures analysis of variance and the Wilcoxon test for RPE. The results indicated that all protocols significantly increased HR, both immediately postexercise and during the subsequent 60 min (P<0·05), and postexercise DP (P<0·05), but there were no differences between protocols. The protocols of LI and LI+BFR reduced postexercise SpO2 (P = 0·033, P = 0·007), and the LI+BFR protocol presented a perception of greater exertion in the lower limbs compared with HI (P = 0·022). We conclude that RE performed at low intensity combined with BFR seems to reduce the SpO2 after exercise and increase HR and DP while maintaining a perception of greater exertion on the lower limbs.

Acute Effects of Different Stretching Techniques on the Number of Repetitions in A Single Lower Body Resistance Training Session

Abstract This study aimed to investigate the acute effects of passive static and ballistic stretching on maximal repetition performance during a resistance training session (RTS). Nine male subjects underwent three experimental conditions: ballistic stretching (BS); passive static stretching (PSS); and a specific warm-up (SW). The RTS was composed of three sets of 12RM for the following exercises: leg press 45 (LP), leg extension (LE), leg curl (LC), and plantar flexors (PF). Performance of six sessions was assessed 48 hours apart. The first visit consisted of a familiarization session including stretching methods and exercises used in the RTS. On the second and third visit, a strength test and retest were performed. During the fourth to the sixth visit, the volunteers randomly performed the following protocols: BS+RTS; PSS+RTS; or SW+RTS. For the sum of the RM number of each three-set exercise, significant differences were found between PSS vs. SW for the LP (p = 0.001); LE (p = 0.005); MF (p = 0.001); and PF (p = 0.038). For the comparison between the methods of stretching PSS vs. BS, significant differences were found only for the FP (p = 0.019). When analyzing the method of stretching BS vs. SW, significant differences were found for the LP (p = 0.014) and MF (p = 0.002). For the total sum of the RM number of three sets of the four exercises that composed the RTS, significant differences were observed (p < 0.05) in the following comparisons: PPS vs. SW (p = 0.001), PPS vs. BS (p = 0.008), and BS vs. SW (p = 0.002). Accordingly, the methods of passive static and ballistic stretching should not be recommended before a RTS.

Hypotensive effects and performance responses between different resistance training intensities and exercise orders in apparently health women.

To compare the hypotensive effect and performance responses between different resistance training intensities and different exercise orders in apparently healthy women, thirteen apparently healthy women performed four resistance training sessions in randomized order. One group performed the resistance training exercises with 60% of 1RM (SeqA60%): leg press (LG), chest press (CP), leg extension (LE), lat pull down (PD), leg curl (LC) and biceps curl (BC). Another group performed the resistance training exercises with 80% of 1RM (SeqA80%) with the same exercise order. Two other groups performed the resistance training exercises with 60% (SeqB60%) and 80% of 1RM (SeqB80%), however, in another sequence of exercises: CP, PD, BC or LG, LE, LC. The blood pressure was measured before, and at every 15 min until 60 min postexercise. The different intensities and different exercise orders resulted in a significant hypotensive effect in systolic and diastolic blood pressures that remained until 15 min. In addition, significant reductions in systolic blood pressure were observed at 30 min for SeqA in both intensities and for SeqB with intensities of 80% of 1RM. However, there was no significant difference between intensities and different prescription orders (P>0·05). Although the current study showed significant decreases in systolic and diastolic blood pressures after different resistance training sessions, the manipulation of intensity and exercise sequence, such as those used in the present study, was not able to generate significant changes in the duration and magnitude of hypotensive effect.

Effects of High-Intensity Blood Flow Restriction Exercise on Muscle Fatigue

Abstract Strength training combined with blood flow restriction (BFR) have been used to improve the levels of muscle adaptation. The aim of this paper was to investigate the acute effect of high intensity squats with and without blood flow restriction on muscular fatigue levels. Twelve athletes (aged 25.95 ± 0.84 years) were randomized into two groups: without Blood Flow Restriction (NFR, n = 6) and With Blood Flow Restriction (WFR, n = 6) that performed a series of free weight squats with 80% 1-RM until concentric failure. The strength of the quadriceps extensors was assessed in a maximum voluntary isometric contraction integrated to signals from the surface electromyogram. The average frequency showed significant reductions in the WFR group for the vastus lateralis and vastus medialis muscles, and intergroup only for the vastus medialis. In conclusion, a set of squats at high intensity with BFR could compromise muscle strength immediately after exercise, however, differences were not significant between groups.

Effects of resistance training with blood flow restriction on haemodynamics: a systematic review

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.

Effect of strength training with blood flow restriction on muscle power and submaximal strength in eumenorrheic women.

Blood flow restriction (BFR) training stimulates muscle size and strength by increasing muscle activation, accumulation of metabolites and muscle swelling. This method has been used in different populations, but no studies have evaluated the effects of training on muscle power and submaximal strength (SS) in accounted for the menstrual cycle. The aim of this study was to analyse the effect of strength training (ST) with BFR on the muscle power and SS of upper and lower limbs in eumenorrheic women. Forty untrained women (18–40 years) were divided randomly and proportionally into four groups: (i) high‐intensity ST at 80% of 1RM (HI), (ii) low‐intensity ST at 20% of 1RM combined with partial blood flow restriction (LI + BFR), (iii) low‐intensity ST at 20% of 1RM (LI) and d) control group (CG). Each training group performed eight training sessions. Tests with a medicine ball (MB), horizontal jump (HJ), vertical jump (VJ), biceps curls (BC) and knee extension (KE) were performed during the 1st day follicular phase (FP), 14th day (ovulatory phase) and 26–28th days (luteal phase) of the menstrual cycle. There was no significant difference among groups in terms of the MB, HJ, VJ or BC results at any time point (P>0·05). SS in the KE exercise was significantly greater in the LI + BFR group compared to the CG group (P = 0·014) during the LP. Therefore, ST with BFR does not appear to improve the power of upper and lower limbs and may be an alternative to improve the SS of lower limbs of eumenorrheic women.

Does a resistance exercise session with continuous or intermittent blood flow restriction promote muscle damage and increase oxidative stress

ABSTRACT 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.

The Effect of a Long-Term, Community-Based Exercise Program on Bone Mineral Density in Postmenopausal Women with Pre-Diabetes and Type 2 Diabetes

Abstract The aim of this study was to evaluate the impact of a community-based exercise program on bone mineral density and body composition in postmenopausal women with pre-diabetes and type 2 diabetes. Twenty postmenopausal women (aged 61.3 ± 6.0 years) with pre-diabetes and type 2 diabetes were randomly assigned to a community-based exercise program group (n=10) or a control group (n=10). The community-based exercise program was multicomponent, three days per week for 32 weeks, and included walking, resistance and aquatic exercises. Body composition and bone mineral density were measured pre and post-training by dual X-ray absorptiometry. In the exercise group significant increases were found in the ward’s triangle bone mineral density (+7.8%, p=0.043), and in fat-free mass (+2.4%, p=0.018). The findings suggest that regular multicomponent training is effective in preventing osteoporosis and sarcopenia among postmenopausal women with pre-diabetes and type 2 diabetes.

The effects of water-based exercise in combination with blood flow restriction on strength and functional capacity in post-menopausal women

Water-based exercise and low-intensity exercise in combination with blood flow restriction (BFR) are two methods that have independently been shown to improve muscle strength in those of advancing age. The objective of this study was to assess the long-term effect of water-based exercise in combination with BFR on maximum dynamic strength and functional capacity in post-menopausal women. Twenty-eight women underwent an 8-week water-based exercise program. The participants were randomly allocated to one of the three groups: (a) water exercise only, (b) water exercise + BFR, or (c) a non-exercise control group. Functional capacity (chair stand test, timed up and go test, gait speed, and dynamic balance) and strength testing were tested before and after the 8-week aquatic exercise program. The main findings were as follows: (1) water-based exercise in combination with BFR significantly increased the lower limb maximum strength which was not observed with water-based exercise alone and (2) water-based exercise, regardless of the application of BFR, increased functional performance measured by the timed up and go test over a control group. Although we used a healthy population in the current study, these findings may have important implications for those who may be contraindicated to using traditional resistance exercise. Future research should explore this promising modality in these clinical populations.