Resistance Training Increases Muscle Strength Research Articles

Managing Psoriatic Arthritis With Different Types of Physical Activity: A Literature Review

Up to 30% of people with psoriasis may develop psoriatic arthritis (PsA), a complicated inflammatory disease characterized by skin signs, joint discomfort, and swelling. Although pharmaceutical therapies have been the primary component of traditional PsA care, the advantages of physical activity are becoming more widely acknowledged. This review looks at how exercise can help manage PsA, with particular emphasis on several types of exercise, including resistance training, functional training, aerobic training, and high-intensity interval training (HIIT). Research indicates that resistance training increases muscle strength and functional ability while aerobic exercise lessens tiredness and musculoskeletal pain. Without escalating disease activity, HIIT reduces fatigue and enhances cardiorespiratory fitness. The review also looks at the relationship between physical activity and PsA symptoms including enthesitis and bone marrow edema (BME). Research shows that exercise does not worsen BME, and even if it can cause enthesitis, the advantages of exercise in terms of lowering overall disease activity and enhancing quality of life exceed the dangers. To sum up, customized exercise regimens are crucial for PsA management and have a major positive impact on patient well-being and disease control.

Resistance training to reduce resting blood pressure and increase muscle strength in users and non-users of anti-hypertensive medication: A meta-analysis

ABSTRACT Objective: The aim of this study was to conduct a systematic review with meta-analysis to analyze the effect of resistance training variables prescription on resting systolic (SBP) and diastolic blood pressure (DBP) and muscle strength changes. Methods: The search was conducted in the PubMed, Web of Science, and SPORTDiscus databases until August 2020 for randomized controlled trials with non-exercising control group. Results: In total, 36 studies qualified for inclusion in this meta-analysis. Eleven studies included users of antihypertensive medication, while the remaining 25 studies were conducted with non-users of antihypertensive medication. Resistance training only reduced SBP (−0.56 [−0.77 to −0.35]; P < .001) and DBP (−0.46 [−0.68 to −0.24]; P < .001) in anti-hypertensive medication users, with changes ranging from −6.1 to −2.8 mmHg for SBP and −4.6 to −1.6 mmHg for DBP. Muscle strength increased significantly in both users (0.76 [0.49 to 1.02]; P < .001) and non-users of antihypertensive medication (0.94 [0.71 to 1.16]; P < .001). Resistance training should be performed by users and non-users of antihypertensive medication for 8 to 16 weeks (2 to 3 days a week) and 8 to 12 non-failure repetitions. However, users should train with less load (60–80 vs 70–85% 1RM) and exercise sets (1–3 vs 2–4) than non-users of antihypertensive medication. Conclusion: Resistance training increases muscle strength and reduces resting SBP and DBP in individuals under BP pharmacological therapy, while in individuals who do not use antihypertensive drugs, resistance training only increases strength.

Eccentric, but not concentric blood flow restriction resistance training increases muscle strength in the untrained limb

ObjectivesLittle is known regarding the variables or mechanisms mediating cross-education as a result of resistance training. Therefore, the purpose of the present study was to examine the effects of low-load eccentric-only blood flow restriction (Ecc-BFR) and low-load concentric-only BFR (Con-BFR) on indices of cross-education. DesignThirty-six women were randomly assigned to 4-wks of unilateral resistance training with Ecc-BFR (n = 12), Con-BFR (n = 12) or control (no intervention, n = 12) group. Eccentric peak torque, concentric peak torque, maximal voluntary isometric contraction torque, muscle thickness, and muscle activation were assessed from the contralateral, untrained arm. ResultsMuscle strength (collapsed across mode) increased from 0-wk to 2-wks (4.9%) and 4-wks (13.0%) for Ecc-BFR only. There were increases in muscle activation (collapsed across mode and group) regardless of training modality, but there were no changes in muscle size for any of the conditions. ConclusionsThe findings of the present study indicated that low-load Ecc-BFR increased muscle strength. The increases in muscle strength as a result of Ecc-BFR were not mode-specific. Thus, low-load Ecc-BFR provides a unique alternative to maintain muscle function in an untrained limb that may have application during limb immobilization and rehabilitation practices.

Contralateral Effects by Unilateral Eccentric versus Concentric Resistance Training.

Unilateral resistance training increases muscle strength of the contralateral homologous muscle by the cross-education effect. Muscle damage induced by second eccentric exercise bout is attenuated, even when it is performed by the contralateral limb. The present study compared the effects of unilateral eccentric training (ET) and concentric training (CT) of the elbow flexors (EF) on maximal voluntary isometric contraction (MVC) strength and muscle damage of the contralateral untrained EF. Young men were placed into ET, CT, ipsilateral repeated bout (IL-RB), and contralateral repeated bout (CL-RB) groups (n = 12 per group). The ET and CT groups performed unilateral EF training consisting of five sets of six eccentric and concentric contractions, respectively, once a week for 5 wk by increasing the intensity from 10% to 100% of MVC, followed by 30 maximal eccentric contractions (30MaxEC) of the opposite EF 1 wk later. The IL-RB group performed two bouts of 30MaxEC separated by 2 wk using the nondominant arm, and CL-RB group performed two bouts of 30MaxEC with a different arm for each bout in 1-wk apart. The MVC increased (P < 0.05) greater for the trained (19% ± 8%) and untrained (11% ± 5%) arms in ET when compared with those in CT (10% ± 6%, 5% ± 2%). The magnitude of changes in muscle damage markers was reduced by 71% ± 19% after the second than the first bout for IL-RB group, and by 48% ± 21% for CL-RB group. Eccentric training and CT attenuated the magnitude by 58% ± 25% and 13% ± 13%, respectively, and the protective effect of ET was greater (P < 0.05) than CL-RB, but smaller (P < 0.05) than IL-RB. These results showed that cross-education effect was stronger for ET than CT, and progressive ET produced greater contralateral muscle damage protective effect than a single eccentric exercise bout.

Resistance Training Increases Muscle Strength and Muscle Size in Patients With Liver Cirrhosis

Cirrhosis is often complicated by reduced muscle mass and strength, which limits the ability to perform daily activities and affects quality of life. Resistance training can increase muscle strength and mass in elderly and chronically ill patients. We performed a randomized controlled trial to investigate whether resistance training increases muscle strength and size in patients with compensated cirrhosis. We performed a prospective study of 39 patients with cirrhosis (Child-Pugh class A or B) seen at an outpatient clinic in Denmark from January 2015 through March 2017. Participants protein intake and activity levels were registered daily. Participants were randomly assigned (1:1) to a group that performed 36 1-hour sessions of physical exercise (supervised progressive resistance training for 1 hour, 3 times weekly for 12 weeks) or a control group (no change in daily activity level). Maximal muscle strength was measured as the peak torque in isokinetic knee extension and muscle size was measured as the cross-sectional area of the quadriceps muscle, assessed by magnetic resonance imaging of the thigh. The exercise group increased their muscle strength by 13% (from a mean 119 Nm to 134 Nm)-an 11 Nm greater gain in mean strength than that of the control group (P = .05). The exercise group increased their quadriceps cross-sectional area by 10% (from a mean 58.5 cm2 to 64.6 cm2)-a 4.4 cm2 greater gain than that of the control group (P < .01). The exercise group had significant increases in whole-body lean mass and body cell mass, and significant increases in 6-minute walking distance and the mental component summary of the short form-36 questionnaire. Adverse events were minor and equal between groups. In a randomized trial of patients with compensated cirrhosis, we found that 12 weeks of supervised progressive resistance training increased muscle strength and size and had beneficial effects on general performance measures, compared with patients who did not change their daily activity routine (control subjects). ClinicalTrials.gov no: NCT02343653.

Perceptual effects and efficacy of intermittent or continuous blood flow restriction resistance training

Blood flow restriction (BFR) exercise may be an alternative form of resistance training; however, a side of effect of BFR resistance exercise is acute muscle pain. Typically, BFR exercise studies restrict blood flow with a cuff continuously during the exercise bout, including rest periods. However, others have used intermittent BFR where the cuff is inflated only during sets. We performed two studies to compare intermittent and continuous BFR exercise. In study one, eleven subjects randomly proceeded through three treatments of unilateral leg extensions to failure: (i) continuous BFR, (ii) intermittent BFR and (iii) control (exercise without BFR). Pain measurements were taken immediately after each set. In study two, subjects (n = 32) underwent a 5-week resistance training programme after random assignment to one of the three conditions. Lean mass and strength were assessed at baseline and after training. Continuous BFR resulted in significantly greater pain than intermittent BFR or control. Both BFR conditions resulted in significantly fewer repetitions to failure than control. This suggests that an acute bout of intermittent BFR exercise may produce as much muscle fatigue as an acute bout of continuous BFR exercise, but with less pain. With training, maximal knee extension (P = 0·033) and maximum knee flexion (P = 0·007) strength increased among all groups. There were no significant differences between groups in strength or lean mass. These results suggest that short-term low-load resistance training increases muscle strength to a similar extent as low-load resistance training without BFR.

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.

Short-term resistance training with blood flow restriction enhances microvascular filtration capacity of human calf muscles

Resistance training increases muscle strength and endurance but may require high intensity and long duration to enhance capillarity. Vascular occlusion during low-load resistance training augments the strength and endurance gains compared with low-load resistance training alone, but in this study we investigated whether it also promotes microvascular filtration capacity, an index of capillarity. Nine healthy males performed short-term low-intensity resistance training of the calf muscles (four sets of 50 heel raises, three times a week for 4 weeks) under restricted (thigh cuff inflated to 150 mmHg on the non-dominant leg) or unrestricted (dominant leg without thigh cuff) blood flow conditions. Before and after resistance training, calf filtration capacity and resting blood flow were assessed by strain gauge plethysmography, and calf muscle strength and fatigue were assessed respectively by maximal voluntary contraction and force decline during electrically evoked ischaemic contractions in both legs. Calf filtration capacity increased by 26% in the restricted leg but did not increase significantly in the unrestricted leg. Calf muscle strength was 18% greater in the restricted leg but unchanged in the unrestricted leg. Calf muscle fatigue and resting blood flow did not change in either leg. Resistance training promoted microvascular filtration capacity, an effect that was somewhat enhanced by blood flow restriction, and could be due to increased capillarization.

Concentric resistance training increases muscle strength without affecting microcirculation

Purpose While the evidence is conclusive regarding the positive effects of endurance training, there is still some controversy regarding the effects of resistance training on muscular capillarity. Thus, the purpose was to assess whether resistance strength training influences resting skeletal muscle microcirculation in vivo. Materials and methods Thirty-nine middle-aged subjects (15 female, 24 male; mean age, 54 ± 9 years) were trained twice a week on an isokinetic system (altogether 16 sessions lasting 50 min, intensity 75% of maximum isokinetic and isometric force of knee flexors and extensors). To evaluate success of training, cross-sectional area (CSA) of the quadriceps femoris muscle and its isokinetic and isometric force were quantified. Muscular capillarization was measured in biopsies of the vastus lateralis muscle. In vivo, muscular energy and lipid metabolites were quantified by magnetic resonance spectroscopy and parameters of muscular microcirculation, such as local blood volume, blood flow and velocity, by contrast-enhanced ultrasound analyzing replenishment kinetics. Results The significant ( P < 0.001) increase in CSA (60 ± 16 before vs. 64 ± 15 cm 2 after training) and in absolute muscle strength (isometric, 146 ± 44 vs. 174 ± 50 Nm; isokinetic, 151 ± 53 vs. 174 ± 62 Nm) demonstrated successful training. Neither capillary density ex vivo (351 ± 75 vs. 326 ± 62) nor ultrasonographic parameters of resting muscle perfusion were significantly different (blood flow, 1.2 ± 1.2 vs. 1.1 ± 1.1 ml/min/100 g; blood flow velocity, 0.49 ± 0.44 vs. 0.52 ± 0.74 mm s −1). Also, the intensities of high-energy phosphates phosphocreatine and β-adenosintriphosphate were not different after training within the skeletal muscle at rest (β-ATP/phosphocreatine, 0.29 ± 0.06 vs. 0.28 ± 0.04). Conclusion The significant increase in muscle size and strength in response to concentric isokinetic and isometric resistance training occurs without an increase in the in vivo microcirculation of the skeletal muscles at rest.

The potential benefits of creatine and conjugated linoleic acid as adjuncts to resistance training in older adults

Human aging is associated with a significant reduction in muscle mass (sarcopenia) resulting in muscle weakness and functional limitations in the elderly. Sarcopenia has been associated with mitochondrial dysfunction and the accumulation of mtDNA deletions. Resistance training increases muscle strength and size and can increase mitochondrial capacity and decrease oxidative stress in older adults. Creatine monohydrate (CrM) and conjugated linoleic acid (CLA) have biological effects that could enhance some of the beneficial effects of resistance training in older adults (i.e., up arrow fat-free mass, down arrow total body fat). We have completed two resistance-training studies with CrM alone and CrM+CLA supplementation in older adults to evaluate the independent effects of exercise and dietary supplements, as well as their interactive effects. Our studies, and several others, have found that CrM enhanced the resistance exercise mediated gains in fat-free mass and strength. More recently, we found that the addition of CLA also lead to a significant reduction of body fat after six months of resistance training in older adults. Older adults have fewer wild-type mtDNA copies and higher amounts of mtDNA deletions as compared with younger adults in mature skeletal muscle; however, these deletions are not seen in the satellite cell-derived myoblast cultures. These findings, and the fact that mtDNA deletions are lower and wild-type mtDNA copy number is higher after resistance training in older adults, suggests that activation of satellite cells secondary to resistance exercise-induced muscle damage can dilute or "shift" the proportion of mtDNA genotype towards that of a younger adult. Recent evidence suggests that CrM supplementation in combination with strength training can enhance satellite cell activation and total myonuclei number per muscle fiber in young men. Future studies are required to determine whether the mitochondrial adaptations to resistance exercise in older adults are further enhanced with CrM supplementation and whether this is due to increased recruitment of satellite cells. It will also be important to determine whether these changes are maintained over a longer time period.