Blood pressure responsiveness to resistance training in the hypertensive older adult: a randomized controlled study.

Different lifestyle changes have been employed to improve clinical hypertension. However, there is scarce evidence on the blood pressure responsiveness to resistance training (RT) in hypertensive older adults. Consequently, little is known about some participants clinically reducing blood pressure and others not. Thus, we investigate the effects and responsiveness of RT on blood pressure in hypertensive older adults. We secondarily evaluated the biochemical risk factors for cardiovascular disease and functional performance. Older participants with hypertension were randomly assigned into RT (n = 27) and control group (n = 25). Blood pressure, functional performance (timed up and go, handgrip strength, biceps curl and sit-to-stand), fasting glucose, and lipid profiles were evaluated preintervention and postintervention. The statistic was performed in a single-blind manner, the statistician did not know who was the control and RT. RT was effective in reducing systolic blood pressure (SBP) (pre 135.7 ±â€…14.7; post 124.7 ±â€…11.0; P  < 0.001) and the responses to RT stimuli varied noticeably between hypertensive older adults after 12 weeks. For example, 13 and 1 responders displayed a minimal clinical important difference for SBP attenuation (10.9 mmHg) in the RT and control groups, respectively. RT improved the functional performance of older people with hypertension, while no differences were found in biochemical parameters (triglycerides, HDL, LDL, fasting glucose) after 12 weeks. In conclusion, responses to RT stimuli varied noticeably between hypertensive individuals and RT was effective in reducing SBP.

Reliability and Validity of a Portable Traction Dynamometer in Knee-Strength Extension Tests: An Isometric Strength Assessment in Recreationally Active Men.

BACKGROUND: the study determined the validity and reliability of measurements obtained using the portable traction dynamometer (PTD) (E-Lastic, E-Sports Solutions, Brazil) and the reproducibility between evaluators (precision) in the evaluation of the isometric muscle strength of the knee extensors of healthy male adults, compared to measurements obtained with the "gold standard" computerized dynamometer (CD) (Biodex System 3, Nova York, NY, USA). METHODS: we evaluated sixteen recreationally active men (29.50 ± 7.26 years). The test-retest reliability of both equipment to determine quadriceps strength, agreement analysis, and the minimal important difference were verified. RESULTS: excellent test-retest interrater reliability was observed for absolute and relative measurements, with a low absolute error for both sets of equipment and excellent validity of the PTD against the CD, as verified by linear regression and Pearson's correlation coefficient. CONCLUSIONS: PTD is a valid and reliable instrument for assessing the isometric strength of knee extensors, with results similar to the isometric CD "gold standard".

Initial Muscle Quality Affects Individual Responsiveness of Interleukin-6 and Creatine Kinase following Acute Eccentric Exercise in Sedentary Obese Older Women.

This study aimed to evaluate the time course and responsiveness of plasma interleukin-6 (IL-6) and creatine kinase (CK) levels following acute eccentric resistance exercise in sedentary obese older women with a different muscle quality index (MQI). Eighty-eight participants (69.4 ± 6.06 years) completed an acute eccentric resistance exercise (7 sets of 10 repetitions at 110% of 10-repetition maximum with 3 min rest interval). Participants were divided into two groups: high or low MQI according to 50th percentile cut-off. The responsiveness was based on minimal clinical important difference. There were no differences between groups and time on IL-6 and CK levels (p > 0.05). However, the high MQI group displayed a lower proportion of low responders (1 for laboratory and 2 for field-based vs. 5 and 4) and a higher proportion of high responders for IL-6 (7 for laboratory and 6 for field-based vs. 4 and 5) compared to low MQI group. In addition, the high MQI group showed a higher proportion of high responders for CK (11 for laboratory and 9 for field-based vs. 6 and 6) compared to low MQI. A prior MQI screening can provide feedback to understand the magnitude response. Individual responsiveness should be taken into consideration for maximizing eccentric exercise prescription.

An overview of the level of dietary support in the gut microbiota at different stages of life: A systematic review.

BACKGROUND & AIMS: The gut microbiome is an essential factor for the health of the host. Several factors may alter the gut's microbiota composition, including genetic factors, lifestyle, aging, and dietary intervention. This process can be an essential element in the prevention and treatment of diseases associated with microbiome dysfunction through appropriate dietary interventions. Based on this context, a systematic review was carried out in order to assess the effect of dietary intervention on the profile of the gut microbiota throughout different stages of life. METHODS: The systematic review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA), with the eligibility criteria following the principle of PICOS. The literature search was carried out in 2019 throughout PubMed/MEDLINE, Scopus, and Science Direct. Thus, 1237 studies were selected, and 40 articles were included by criteria. RESULTS: According to the level of evidence of Centre for Evidence-Based Medicine (OCEBM), 21 studies reached the level of evidence B1, 15 articles were classified with B2, and four articles with B3. No dietary intervention was applied at all stages of life, nor with similar proportions of intervention. No dietary intervention was applied at all stages of life, nor with similar proportions of intervention. On the other hand, dietary interventions alter the intestinal microbiota in different pathological realities. CONCLUSIONS: Different dietary interventions change the microbiome composition at all stages of life in healthy and pathological individuals. However, more clinical studies are needed to identify the specifics of each stage in response to interventions.

Advancements and critical steps for statistical analyses in blood pressure response to resistance training in hypertensive older women: a methodological approach.

BACKGROUND: Repeated measures analysis of covariance and three-way analysis of variance with repeated measures are common statistical methods. For a valid interpretation of blood pressure (BP) response to exercise, a variety of additional statistical methods must be implemented. Four additional statistical methods are presented: technical error of measurement (SEM), smallest real difference (SRD), magnitude-based inference and mixed effect modeling technique (MEM). The aim of this perspective article is to demonstrate how to apply already known statistical analyses regarding BP responsiveness in order to improve interpretation and achieve higher reliability for future studies in exercise science. METHODS: A total of 27 hypertensive older women (aged 68.37 ± 5.55 years) participated in the present study. A whole-body resistance training (RT) program was performed on two nonconsecutive days per week for 10 weeks. BP was monitored during the 10-week RT intervention and after 15 weeks of detraining. First, individuals were classified as high and low responders, then statistical methods to analyze data included the use of SEM, SRD, magnitude-based inference and MEM. RESULTS: When magnitude-based inference was used to classify responsiveness, most participants displayed a trivial response. Decrements in SBP between 1 and 10 mmHg were not clinically meaningful but fell within the measurement error of the SBP measurements. Baseline SBP and time of training predicted post-SBP response. CONCLUSION: Changes over time and declines in SBP might not be a SRD and fell in the SEM. Moreover, SBP responsiveness was the result of inappropriate control of covariates such as period of training.

Effect of high-velocity and traditional resistance exercise on serum antioxidants and inflammation biomarkers in older women: A randomized crossover trial.

INTRODUCTION: Contrary to the production of oxidant and inflammation biomarkers, antioxidant enzymes decrease with age and the adaptive response to oxidative stress is reduced. The effects of the different resistance exercise protocols to attenuate these conditions are largely unexplored. OBJECTIVE: We compared the acute effects of traditional resistance exercise (TRE) and high velocity RE (HVRE) on inflammatory biomarkers and antioxidant activity in elderly women. METHODS: Fourteen elderly women (67 ± 7 years) were randomly assigned to TRE or HVRE. Blood samples were collected to measure inflammatory markers and antioxidant enzymes at three time-points (pre-exercise, post-exercise, 30 min post-exercise). RESULTS: TRE and HVRE induced acute reductions over time on tumor necrosis factor-alpha, interleukin-6 (IL-6), soluble receptor of IL-6 (sIL-6R), as well in catalase, glutathione and superoxide dismutase antioxidant levels without differences between groups. In addition, TRE and HVRE groups displayed acute increments in interleukin-10 (IL-10) and IL-10/IL-6 ratio over time, while the HVRE protocol displayed higher IL-10 values post-exercise and 30 min post-exercise time points as compared with TRE. Based on magnitude based inference, subjects from the HVRE group demonstrated superior responsiveness for IL-6 and IL-10 as compared with the TRE group. All participants from the HVRE group displayed a minimal clinical important difference on IL-10 levels as compared to only two persons from the TRE group. CONCLUSION: Both RE protocols were capable of positive changes in inflammatory and antioxidant status in elderly subjects, but HVRE demonstrated a superior response on IL-10. The HVRE may be incorporated to exercise recommendation in this population.

Potential Implications of Blood Flow Restriction Exercise on Vascular Health: A Brief Review.

Blood flow restriction (BFR) exercise (a.k.a. occlusion training) has emerged as a viable surrogate to traditional heavy-load strength rehabilitation training for a broad range of clinical populations including elderly subjects and rehabilitating athletes. A particular benefit of BFR exercise is the lower stress upon the joints as compared to traditional heavy resistance training, with similar gains in muscle strength and size. The application of an inflatable cuff to the proximal portion of the limbs increases the pressure required for venous return, leading to changes in venous compliance and wall tension. However, it is not known if long-term benefits of BFR exercise on muscle strength and size outweigh potential short and long-term complications on vascular health. BFR exercise could lead to clinical deterioration of the vasculature along with sympathetic overactivity and decreased vascular function associated with retrograde shear stress. This raises a fundamental question: Given the concern that excessive restriction could cause injury to endothelial cells and might cause detrimental effects on endothelial function, even in healthy individuals, should we critically re-evaluate the safety of this method for the general population? From this perspective, the purpose of this manuscript is to review the effects of BFR exercise on vascular function, and to provide relevant insights for training practice as well as future directions for research.

Relation Between Relative Handgrip Strength, Chronological Age and Physiological Age with Lower Functional Capacity in Older Women.

PURPOSE: Relative handgrip strength (RHGS), Aged Based on Exercise Stress Testing (A-BEST), and chronological age were evaluated as predictors of impaired mobility in older women. METHODS: Participants included 88 older women (mean age 68.13±6.02 years) referred for exercise stress testing. Estimated physiological age was computed based on exercise capacity, chronotropic reserve index, heart rate recovery, and medication that could affect heart rate. RHGS was measured using a validated handgrip hydraulic dynamometer and mobility was evaluated by timed up and go test (TUG-test). A hierarchical multiple regression predicted TUG-test performance from A-BEST, chronological age and RHGS. RESULTS: After adjustment for diabetes, RHGS was the only variable to add significantly to the prediction model (p=0.001). An increase in RHGS of 1 kg/body mass index was associated with a decrease in TUG-test of 0.7 seconds. CONCLUSION: Relative handgrip strength test was a better predictor of impaired mobility when compared with chronological and physiological age in older women. Moreover, RHGS represents an inexpensive, simple, portable, noninvasive measurement for a clinician when compared with an exercise stress testing.

Is Perceived Exertion a Useful Indicator of the Metabolic and Cardiovascular Responses to a Metabolic Conditioning Session of Functional Fitness?

The purpose of this study was to assess whether the self-regulation of training intensity based on rating of perceived exertion (RPE) is a reliable method to control the intensity during metabolic conditioning sessions of functional fitness. In addition, the relationship between RPE and the changes in heart rate, number of repetitions, and lactate responses was also analyzed. Eight male participants (age 28.1 ± 5.4 years; body mass 77.2 ± 4.4 kg; VO2 max: 52.6 ± 4.6 mL·(kg·min)-1 completed two sessions (five to seven days apart), in a randomized order, under different conditions, as follows: (1) all-out (ALL), or (2) self-regulation of intensity based on an RPE of six (hard) on the Borg CR-10 scale (RPE6). The rating of perceived exertion, lactate (LAC), and heart rate (HR) response were measured before, during, and immediately after the sessions. The RPE and LAC during the all-out sessions were higher (p < 0.0005) than the RPE6 session for all of the analyzed time points during the session. There was no difference in the HR area under the curve for the all-out and RPE6 sessions. The average number of repetitions performed was lower (p ≤ 0.009) for the RPE6 session (190.5 ± 12.5 repetitions) when compared to the all-out session (214.4 ± 18.6 repetitions). There was a significant correlation between the RPE and LAC (p = 0.005; r = 0.66; large) and number of repetitions during the session (p = 0.026; r = 0.55; large). No correlation was observed between the RPE and HR (p = 0.147; r = 0.380). These results indicate that the self-regulation of intensity of effort based on the RPE may be a useful tool to control the exercise intensity during a metabolic conditioning session of functional fitness.

Strength and Muscular Adaptations After 6 Weeks of Rest-Pause vs. Traditional Multiple-Sets Resistance Training in Trained Subjects.

Prestes, J, Tibana, RA, de Araujo Sousa, E, da Cunha Nascimento, D, de Oliveira Rocha, P, Camarço, NF, Frade de Sousa, NM, and Willardson, JM. Strength and muscular adaptations after 6 weeks of rest-pause vs. traditional multiple-sets resistance training in trained subjects. J Strength Cond Res 33(7S): S113-S121, 2019-The purpose of this study was to compare the longitudinal effects of 6 weeks of rest-pause vs. traditional multiple-set resistance training (RT) on muscle strength, hypertrophy, localized muscular endurance, and body composition in trained subjects. Eighteen trained subjects (mean ± SD; age = 30.2 ± 6.6 years; weight = 74.8 ± 17.2 kg; height = 171.4 ± 10.3 cm) were randomly assigned to either a traditional multiple-set group (n = 9; 7 men and 2 women; 3 sets of 6 repetitions with 80% of 1-repetition maximum (1RM) and 2-minute rest intervals between sets) or a rest-pause group (n = 9; 7 men and 2 women). The results showed no significant differences (p > 0.05) between groups in 1RM strength (rest-pause: 16 ± 11% for bench press, 25 ± 17% for leg press and 16 ± 10% for biceps curl vs. traditional multiple-set: 10 ± 21% for BP, 30 ± 20% for LP and 21 ± 20% for BC). In localized muscular endurance, the rest-pause group displayed significantly greater (p < 0.05) repetitions, only for the LP exercise (rest pause: 27 ± 8% vs. traditional multiple-set: 8 ± 2%). In muscle hypertrophy, the rest-pause group displayed significantly greater (p < 0.05) thickness, only for the thigh (rest-pause: 11 ± 14% vs. traditional multiple-set: 1 ± 7%). In conclusion, RT performed with the rest-pause method resulted in similar gains in muscle strength as traditional multiple-set training. However, the rest-pause method resulted in greater gains in localized muscular endurance and hypertrophy for the thigh musculature.

Effects of Resistance Training Volume on MMPs in Circulation, Muscle and Adipose Tissue.

The aim of this study was to investigate the effects of different resistance training (RT) volumes on MMP activity in skeletal muscle, visceral adipose tissue and circulation. 21 Wistar rats were randomly divided into 3 groups (n=7 per group): sedentary control (SC); RT with 4 ladder climbs (RT-4; 50, 75, 90 and 100% of their maximal carrying capacity) and RT with 8 ladder climbs (RT-8 with 2 sets for each load). The 8-week RT consisted of climbing a 1.1-m vertical ladder with weights secured to the animals' tails. MMP-2 and -9 activity were analyzed by zymography. RT-8 displayed higher active MMP-2 activity as compared with SC and RT-4 in skeletal muscle (p<0.05). There was no significant difference between groups for pro and intermediate-MMP-2 activity in visceral adipose tissue, while RT-8 presented lower active MMP-2 activity as compared with SC (p<0.05). Plasma pro and active MMP-2 and MMP-9 activity was lower in RT-8 as compared with RT-4 (p<0.05). These results suggest that higher volume RT up-regulates MMP-2 activity in skeletal muscle, while down-regulating MMP-2 in visceral adipose tissue. Moreover, it induces a decrease of MMP-2, 9 activity in circulation. Different tissue and circulatory MMP responses to RT may result in specific remodeling.

Elevated glycated hemoglobin levels impair blood pressure in children and adolescents with type 1 diabetes mellitus.

BACKGROUND: Deregulation of glycemic and glycated hemoglobin (HbA1) levels accelerate the progression of cardiovascular complications in type 1 diabetes mellitus (T1DM). The aim of this study was to investigate the association between HbA1 and changes in blood pressure of children and adolescents with T1DM. METHODS: A total of 60 children and adolescents were recruited and allocated into two groups (prehypertension and control group). Blood pressure and HbA1 were measured by the oscillometric method and high-performance liquid chromatography, respectively. RESULTS: The prehypertensive group had (P < 0.05) higher disease duration, body weight, Z score for body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP) and a higher HbA1 when compared with the control children and adolescents. Multiple regression to predict alterations in DBP from HbA1 adjusted for age, disease duration, and body mass index demonstrated a positive relationship with DBP (P < 0.05). A 1 % increase in HbA1 was associated with 1.73 mmHg increase in DBP. CONCLUSIONS: High levels of HbA1 may be associated with increased blood pressure in T1DM. A tight control of HbA1 levels may provide long-term cardiovascular protection in children and adolescents with T1DM.

Understanding the individual responsiveness to resistance training periodization.

This study was designed to compare the effects of linear periodization (LP) and undulating periodization (UP) on functional capacity, neuromuscular function, body composition, and cytokines in elderly sedentary women. We also aimed to identify the presence of high responders (HR), medium responders (MR), and low responders (LR) for irisin, interleukin-1 beta (IL-1ß), toll-like receptor-4 (TLR-4), and brain-derived neurotrophic factor (BDNF) to resistance training (RT). Forty-nine elderly women were assigned to a control group, LP, and UP scheme. Functional capacity, body composition, maximal strength, irisin, TLR-4, BDNF, and IL-1ß were evaluated. Both periodization models were effective in improving 45° leg press 1RM, chair-stand, arm curl, and time-up and go tests, with no significant differences in body composition and cytokines. Furthermore, HR, MR, and LR were identified for irisin, IL-1ß, TLR-4, and BDNF, with differences between groups and moments. This study provides evidence that both periodization models were effective in improving functional capacity and neuromuscular function, with no effect on body composition and cytokines (probably as a consequence of the different responsiveness). Furthermore, for the first time, HR, MR, and LR were identified for irisin, IL1-ß, TLR-4, and BDNF in response to RT.

Classification of pro-inflammatory status for interleukin-6 affects relative muscle strength in obese elderly women.

BACKGROUND: Obesity, defined by an excess amount of body fat or a percent body fat higher than 30 % for women is a complex chronic disorder with multifactorial etiology and is accompanied by chronic low-grade inflammation, which results in elevated pro-inflammatory cytokines. AIMS: The aim of this study was to compare muscle strength between high and low pro-inflammatory status in obese elderly women and to verify the relationship of IL-6 with muscle strength and fat-free mass. METHODS: Eighty-nine elderly women (age 69.47 ± 6.07 years; body mass 64.70 ± 12.04 kg; height 1.52 ± 0.06 m; body mass index 27.78 ± 4.75 kg/m(2)) were divided into two groups: high and low inflammatory status for IL-6. Lower limb muscle strength was tested using bilateral leg extension with the ten repetitions maximum test, IL-6 was measured by ELISA and body composition by dual-energy X-ray absorptiometry. RESULTS: Women classified from the high pro-inflammatory status presented lower relative muscle strength (P = 0.056) when compared with the low inflammatory status group, with no differences for absolute muscle strength (P = 0.18). There was a significant negative correlation of IL-6 with relative muscle strength (P = 0.03, R = -0.22) and a considerable trend toward significance (P = 0.06, R = -0.19) and negative association with fat-free mass (P = 0.84, R = -0.02). CONCLUSIONS: This study provides insights that a high pro-inflammatory status in sedentary obese elderly women might impair muscle strength and negatively affect fat-free mass. Thus, elderly women classified with high pro-inflammatory status for IL-6 should receive further health care attention to prevent this deleterious condition.