Hélcio Kanegusuku

Efeitos do treinamento resistido sobre a pressão arterial de idosos

O processo de envelhecimento reduz drasticamente a massa, a forca e a potencia musculares, diminuindo a capacidade de execucao das atividades da vida diaria. A pratica de exercicios resistidos pode reverter esse quadro, auxiliando na manutencao da massa muscular e melhorando sua forca e resistencia. No entanto, o envelhecimento ocasiona alteracoes cardiovasculares, que podem resultar em aumento nos niveis de pressao arterial de repouso, sendo importante analisar os efeitos do exercicio resistido sobre a pressao arterial de individuos idosos. O objetivo deste estudo e avaliar o conhecimento cientifico existente sobre as respostas da pressao arterial aos exercicios resistidos e seus mecanismos em idosos. Para tanto, realizou-se uma revisao bibliografica baseada nas literaturas portuguesa e inglesa relacionadas ao tema. Com base nos estudos encontrados, o corpus atual, embora escasso e controverso, sugere que, de forma cronica, os exercicios resistidos podem ter efeito hipotensor em individuos idosos. Entretanto, esse efeito ocorre, principalmente, em idosos normotensos e com o treinamento de baixa intensidade. Os mecanismos envolvidos nessa resposta hipotensora ainda precisam ser elucidados. Embora o treinamento resistido esteja sendo recomendado para idosos e haja alguns indicativos de que ele possa ter efeito hipotensor cronico, ainda ha carencia de dados cientificos e muitas controversias sobre o assunto, o que evidencia que este ainda e um campo aberto a investigacao.The aging process drastically reduces muscle mass, strength and power, decreasing the capacity to perform the activities of daily living. The practice of resistance exercises can reverse this picture, helping to maintain the muscular mass and improving muscular strength and resistance. However, the aging process causes cardiovascular alterations, which can result in increased blood pressure levels at rest and it is important to analyze the effects of resistance exercises on the blood pressure of elderly individuals. The objective of this study is to evaluate the current scientific knowledge on the responses of the blood pressure to resistance exercises and their mechanisms in elderly individuals. In order to do that, we carried out a literature review related to the theme, in both Portuguese and English. Based on the studies found, the current corpus, although scarce and controversial, suggests that, chronically, resistance exercises can have a hypotensive effect on elderly individuals. However, this effect occurs mainly in normotensive elderly individuals submitted to low-intensity training. The mechanisms involved in the hypotensive response still need to be clarified. Although the resistance training is recommended for elderly individuals and there is some evidence that it can have a chronic hypotensive effect, there is still lack of scientific data and much debate on the subject, which demonstrates that this field is still open to investigation.

Effects of walking and strength training on resting and exercise cardiovascular responses in patients with intermittent claudication

BACKGROUND Exercise training is recommended as the first-line therapy for intermittent claudication patients. However, the effects of exercise therapy on cardiovascular function of these patients have been poorly studied. The aim of this study is to compare the effects of walking and strength training on cardiovascular responses assessed at rest and during exercise in patients with intermittent claudication. PATIENTS AND METHODS Thirty-four patients with stable symptoms of intermittent claudication were randomized into two groups: strength training (ST) consisting of eight exercises, three sets of 10 repetitions, intensity of 11 - 13 on 15-grade Borg scale, 2-min interval between sets; and walking training (WT) consisting of walking on a treadmill, 15 bouts of 2-min, intensity of 11 - 13 on 15-grade Borg scale, with a 2-min interval between bouts. Before and after 12 weeks, blood pressure, heart rate and rate pressure product were measured at rest and during a progressive treadmill test until maximal claudication pain. RESULTS Fifteen patients in each group completed the training program. After the training programs, resting systolic blood pressure (ST:-6 ± 13 mmHg and WT:-3 ± 18 mmHg, P = .04), heart rate (ST: -6 ± 10 bpm and WT:-2 ± 9 bpm, P = .03), and rate pressure product (ST:-1485 ± 1442 mmHg*bpm and WT:- 605 ± 2145 mmHg*bpm, P = .01) decreased significantly and similarly in both groups. Submaximal systolic blood pressure (ST: -14 ± 23 mmHg and WT:-6 ± 23 mmHg, P = .02), and rate pressure product (ST:-1579 ± 3444 mmHg*bpm and WT: -1264 ± 3005 mmHg*bpm, P = .04) decreased significantly and similarly in both groups. There were no changes in submaximal heart rate after ST and WT. Maximal systolic blood pressure, heart rate, and rate pressure product did not change in either group, although maximal exercise time increased similarly in the ST and WT groups (+31 ± 19 %, and +31 ± 32 %, respectively, P < .01). CONCLUSIONS Strength and walking trainings promoted similar increases in walking capacity and decreases in resting and submaximal exercise cardiovascular load.

Strength and power training did not modify cardiovascular responses to aerobic exercise in elderly subjects

Resistance training increases muscle strength in older adults, decreasing the effort necessary for executing physical tasks, and reducing cardiovascular load during exercise. This hypothesis has been confirmed during strength-based activities, but not during aerobic-based activities. This study determined whether different resistance training regimens, strength training (ST, constant movement velocity) or power training (PT, concentric phase performed as fast as possible) can blunt the increase in cardiovascular load during an aerobic stimulus. Older adults (63.9 ± 0.7 years) were randomly allocated to: control (N = 11), ST (N = 13, twice a week, 70-90% 1-RM) and PT (N = 15, twice a week, 30-50% 1-RM) groups. Before and after 16 weeks, oxygen uptake (VO(2)), systolic blood pressure (SBP), heart rate (HR), and rate pressure product (RPP) were measured during a maximal treadmill test. Resting SBP and RPP were similarly reduced in all groups (combined data = -5.7 ± 1.2 and -5.0 ± 1.7%, respectively, P < 0.05). Maximal SBP, HR and RPP did not change. The increase in measured VO(2), HR and RPP for the increment in estimated VO(2) (absolute load) decreased similarly in all groups (combined data = -9.1 ± 2.6, -14.1 ± 3.9, -14.2 ± 3.0%, respectively, P < 0.05), while the increments in the cardiovascular variables for the increase in measured VO(2) did not change. In elderly subjects, ST and PT did not blunt submaximal or maximal HR, SBP and RPP increases during the maximal exercise test, showing that they did not reduce cardiovascular stress during aerobic tasks.

Cardiac Work Remains High after Strength Exercise in Elderly

Moderate- to high-intensity strength training is recommended for healthy adults. In young subjects, a single session of strength training decreases blood pressure, while heart rate and cardiac work remain elevated afterwards. However, these effects have not been clearly demonstrated in elderly subjects. To investigate this issue, 16 elderly subjects each underwent a Control and an Exercise (3 sets, 8 RM, 9 exercises) session conducted in random order. Haemodynamic variables and heart rate variability were measured before and after the interventions. Systolic blood pressure did not change after the exercise session but did increase after the control session (+8.1±1.6 mm Hg, P≤0.05). Diastolic blood pressure, as well as systemic vascular resistance increased similarly after both sessions. Cardiac output and stroke volume decreased, while heart rate, rate-pressure product and the low- to high-frequency ratio of heart rate variability increased only after the exercise session ( - 0.5±0.1 L/min, - 9.3±2.0 ml,+3.8±1.6 bpm, +579.3±164.1 mmHg.bpm and +0.71±0.34, P≤0.05). Ambulatory blood pressure was similar after both sessions, while heart rate and rate pressure product remained higher after the exercise session for up to 4.5 h. After a single session of strength training, cardiac sympathetic modulation and heart rate remain elevated in elderly subjects, keeping cardiac work elevated for a long period of time.

Resistance Training with Instability for Patients with Parkinson’s Disease

PURPOSE This randomized controlled trial compared the effects of resistance training (RT) and RT with instability (RTI) on the timed up and go test (TUG), on-medication Unified Parkinsons Disease Rating Scale part III motor subscale score (UPDRS-III), Montreal Cognitive Assessment (MoCA) score, Parkinsons Disease Questionnaire (PDQ-39) score, and muscle strength in the leg press exercise (one-repetition maximum) of patients with Parkinsons disease (PD). METHODS Thirty-nine patients with moderate to severe PD were randomly assigned to a nonexercising control group (C), RT group, and RTI group. The RT and RTI groups performed progressive RT twice a week for 12 wk. However, only the RTI group used high motor complexity exercises (i.e., progressive RT with unstable devices), for example, half squat exercise on the BOSU® device. The primary outcome was mobility (TUG). The secondary outcomes were on-medication motor signs (UPDRS-III), cognitive impairment (MoCA), quality of life (PDQ-39), and muscle strength (one-repetition maximum). RESULTS There were no differences between RTI and RT groups for any of the outcomes at posttraining (P > 0.05). However, there were differences between RTI and C groups in the TUG, MoCA, and muscle strength values at posttraining (P < 0.05). Only the RTI group improved the TUG (-1.9 s), UPDRS-III score (-4.5 score), MoCA score (6.0 score), and PDQ-39 score (-5.2 score) from pre- to posttraining (P < 0.001). Muscle strength improved for both training groups (P < 0.001). No adverse events were reported during the trial. CONCLUSIONS Both training protocols improved muscle strength, but only RTI improved the mobility, motor signs, cognitive impairment, and quality of life, likely because of the usage of high motor complexity exercises. Thus, RTI may be recommended as an innovative adjunct therapeutic intervention for patients with PD.

Effects of resistance training on blood pressure in the elderly

O processo de envelhecimento reduz drasticamente a massa, a forca e a potencia musculares, diminuindo a capacidade de execucao das atividades da vida diaria. A pratica de exercicios resistidos pode reverter esse quadro, auxiliando na manutencao da massa muscular e melhorando sua forca e resistencia. No entanto, o envelhecimento ocasiona alteracoes cardiovasculares, que podem resultar em aumento nos niveis de pressao arterial de repouso, sendo importante analisar os efeitos do exercicio resistido sobre a pressao arterial de individuos idosos. O objetivo deste estudo e avaliar o conhecimento cientifico existente sobre as respostas da pressao arterial aos exercicios resistidos e seus mecanismos em idosos. Para tanto, realizou-se uma revisao bibliografica baseada nas literaturas portuguesa e inglesa relacionadas ao tema. Com base nos estudos encontrados, o corpus atual, embora escasso e controverso, sugere que, de forma cronica, os exercicios resistidos podem ter efeito hipotensor em individuos idosos. Entretanto, esse efeito ocorre, principalmente, em idosos normotensos e com o treinamento de baixa intensidade. Os mecanismos envolvidos nessa resposta hipotensora ainda precisam ser elucidados. Embora o treinamento resistido esteja sendo recomendado para idosos e haja alguns indicativos de que ele possa ter efeito hipotensor cronico, ainda ha carencia de dados cientificos e muitas controversias sobre o assunto, o que evidencia que este ainda e um campo aberto a investigacao.The aging process drastically reduces muscle mass, strength and power, decreasing the capacity to perform the activities of daily living. The practice of resistance exercises can reverse this picture, helping to maintain the muscular mass and improving muscular strength and resistance. However, the aging process causes cardiovascular alterations, which can result in increased blood pressure levels at rest and it is important to analyze the effects of resistance exercises on the blood pressure of elderly individuals. The objective of this study is to evaluate the current scientific knowledge on the responses of the blood pressure to resistance exercises and their mechanisms in elderly individuals. In order to do that, we carried out a literature review related to the theme, in both Portuguese and English. Based on the studies found, the current corpus, although scarce and controversial, suggests that, chronically, resistance exercises can have a hypotensive effect on elderly individuals. However, this effect occurs mainly in normotensive elderly individuals submitted to low-intensity training. The mechanisms involved in the hypotensive response still need to be clarified. Although the resistance training is recommended for elderly individuals and there is some evidence that it can have a chronic hypotensive effect, there is still lack of scientific data and much debate on the subject, which demonstrates that this field is still open to investigation.

High-Intensity Progressive Resistance Training Increases Strength With No Change in Cardiovascular Function and Autonomic Neural Regulation in Older Adults.

The effects of high-intensity progressive resistance training (HIPRT) on cardiovascular function and autonomic neural regulation in older adults are unclear. To investigate this issue, 25 older adults were randomly divided into two groups: control (CON, N = 13, 63 ± 4 years; no training) and HIPRT (N = 12, 64 ± 4 years; 2 sessions/week, 7 exercises, 2–4 sets, 10–4 RM). Before and after four months, maximal strength, quadriceps cross-sectional area (QCSA), clinic and ambulatory blood pressures (BP), systemic hemodynamics, and cardiovascular autonomic modulation were measured. Maximal strength and QCSA increased in the HIPRT group and did not change in the CON group. Clinic and ambulatory BP, cardiac output, systemic vascular resistance, stroke volume, heart rate, and cardiac sympathovagal balance did not change in the HIPRT group or the CON group. In conclusion, HIPRT was effective at increasing muscle mass and strength without promoting changes in cardiovascular function or autonomic neural regulation.

Effects of Progressive Resistance Training on Cardiovascular Autonomic Regulation in Patients With Parkinson Disease: A Randomized Controlled Trial

OBJECTIVE To evaluate the effects of a progressive resistance training (RT) on cardiac autonomic modulation and on cardiovascular responses to autonomic stress tests in patients with Parkinson disease (PD). DESIGN Randomized clinical trial. SETTING The Brazil Parkinson Association. PARTICIPANTS Patients (N=30) with PD (modified Hoehn & Yahr stages 2-3) were randomly divided into 2 groups: a progressive RT group (PD training [PDT] group) and a control group (PD control [PDC] group). In addition, a group of paired healthy control (HC) subjects without PD was evaluated. INTERVENTIONS The PDT group performed 5 resistance exercises, 2 to 4 sets, 12 to 6 repetitions maximum per set. Individuals in the PDC group maintained their usual lifestyle. MAIN OUTCOME MEASURES The PDT and PDC groups were evaluated before and after 12 weeks. The HC group was evaluated once. Autonomic function was assessed by spectral analysis of heart rate variability and cardiovascular responses to autonomic stress tests (deep breathing, Valsalva maneuver, orthostatic stress). RESULTS Compared with baseline, the normalized low-frequency component of heart rate variability decreased significantly after 12 weeks in the PDT group only (PDT: 61±17 normalized units [nu] vs 47±20nu; PDC: 60±14nu vs 63±10nu; interaction P<.05). A similar result was observed for systolic blood pressure fall during orthostatic stress that also was reduced only in the PDT group (PDT: -14±11mmHg vs -6±10mmHg; PDC: -12±10mmHg vs -11±10mmHg; interaction P<.05). In addition, after 12 weeks, these parameters in the PDT group achieved values similar to those in the HC group. CONCLUSIONS In patients with PD, progressive RT improved cardiovascular autonomic dysfunction.

Instability Resistance Training Improves Neuromuscular Outcome in Parkinson's Disease

Purpose This study compared the effects of resistance training (RT) and RT with instability (RTI) on neuromuscular and total training volume (TTV) outcomes obtained as part of the Instability Resistance Training Trial in Parkinsons disease. It also used a linear multiple regression (forward stepwise method) to identify the contribution of neuromuscular outcomes to previously published improvements in the timed-up-and-go test and the Unified Parkinsons Disease Rating Scale, motor subscale score. Methods Thirty-nine patients with moderate to severe Parkinsons disease were randomly assigned to three groups: control (C), RT, and RTI. RT and RTI groups performed resistance exercises twice a week for 12 wk, and only the RTI group used unstable devices to perform resistance exercises. The following neuromuscular outcomes were assessed: quadriceps muscle cross-sectional area, root mean square and mean spike frequency of electromyographic signal, peak torque, rate of torque development, and half relaxation time of the knee extensors and plantarflexors during maximum ballistic voluntary isometric contractions. TTV was calculated for lower limb exercises. Results From pre- to posttraining, RTI improved all of the neuromuscular outcomes (P < 0.05) except half relaxation time of the knee extensors (P = 0.068), despite the lower TTV than RT (P < 0.05). RTI was more effective than RT in increasing the root mean square values of vastus medialis, mean spike frequency of gastrocnemius medialis, and rate of torque development of plantarflexors (P < 0.05). Stepwise regression identified the changes in mean spike frequency of gastrocnemius medialis as the best predictor of improvements in timed-up-and-go test (R2 = 0.58, P = 0.002) and on-medication Unified Parkinsons Disease Rating Scale, motor subscale scores (R2 = 0.40, P = 0.020). Conclusion RTI optimizes neuromuscular adaptations, which partially explains mobility and motor sign improvements in patients with Parkinsons disease.

Resistance training with instability is more effective than resistance training in improving spinal inhibitory mechanisms in Parkinson's disease

This study assessed 1) the effects of 12 wk of resistance training (RT) and resistance training with instability (RTI) on presynaptic inhibition (PSI) and disynaptic reciprocal inhibition (DRI) of patients with Parkinsons disease (PD); 2) the effectiveness of RT and RTI in moving PSI and DRI values of patients toward values of age-matched healthy controls (HC; Z-score analysis); and 3) associations between PSI and DRI changes and clinical outcomes changes previously published. Thirteen patients in RT group, 13 in RTI group, and 11 in a nonexercising control group completed the trial. While RT and RTI groups performed resistance exercises twice a week for 12 wk, only the RTI group used unstable devices. The soleus H reflex was used to evaluate resting PSI and DRI before and after the experimental protocol. The HC (n = 31) was assessed at pretest only. There were significant group × time interactions for PSI (P < 0.0001) and DRI (P < 0.0001). RTI was more effective than RT in increasing the levels of PSI (P = 0.0154) and DRI (P < 0.0001) at posttraining and in moving PSI [confidence interval (CI) 0.1-0.5] and DRI (CI 0.6-1.1) levels to those observed in HC. There was association between DRI and quality of life changes (r = -0.69, P = 0.008) and a strong trend toward association between PSI and postural instability changes (r = 0.60, P = 0.051) after RTI. RTI increased PSI and DRI levels more than RT, reaching the average values of the HC. Thus RTI may cause plastic changes in PSI and DRI pathways that are associated with some PD clinical outcomes. NEW & NOTEWORTHY Patients with Parkinsons disease (PD) have motor dysfunction. Spinal inhibitory mechanisms are important for modulating both supraspinal motor commands and sensory feedback at the spinal level. Resistance training with instability was more effective than resistance training in increasing the levels of presynaptic inhibition and disynaptic reciprocal inhibition of lower limb at rest of the patients with PD, reaching the average values of the healthy controls.