Low-intensity Resistance Exercise Research Articles

The Effect of Combining Blood Flow Restriction with the Nordic Hamstring Exercise on Hamstring Strength: Randomized Controlled Trial.

(1) Background: It is a matter of curiosity what effect the blood flow restriction (BFR) method, which is usually combined with low-intensity resistance exercises, will have when used with high-intensity eccentric exercises. (2) Methods: The present study examined the effects of combining BFR with nordic hamstring exercises (NHEs) on hamstring muscle strength, bilateral deficit (BLD), and training volume. Thirty young female volleyball players, who trained three times a week, participated voluntarily in the study. These players were stratified into three groups, each comprising ten individuals: a control group (CG), an NHE group, and an NHE + BFR group. Hamstring muscle strength and BLD values were determined using an H-BORD device, while training volume was measured in terms of sets and repetitions. (3) Results: Statistical analysis revealed that there were no statistically significant differences in non-dominant and dominant leg peak torque parameters in the exercise groups (F = 2.65; p = 0.097; ηp2 = 0.17; F = 1.15; p = 0.0334; ηp2 = 0.084), while the total training volume was lower in the NHE + BFR group. (4) Conclusions: As a result, it was seen that adding the BFR method to NHE did not provide additional gains. However, due to the low training volume of BFR + NHE, it may be recommended to apply BFR together with NHE to athlete groups.

8주 간의 혈류제한 요법과 저-강도 저항운동이 골연골 재생술을 받은 중년여성의 슬관절 신전 근력, 균형, 기능 및 관절염 지수에 미치는 효과

8주 간의 혈류제한 요법과 저-강도 저항운동이 골연골 재생술을 받은 중년여성의 슬관절 신전 근력, 균형, 기능 및 관절염 지수에 미치는 효과

Physiological and clinical effects of low-intensity blood-flow restricted resistance exercise compared to standard rehabilitation in adults with knee osteoarthritis–Protocol for a randomized controlled trial

Introduction Osteoarthritis (OA) is a common disease with high socioeconomical costs. In Denmark, standard rehabilitation (SR) consists of a combination of patient education and supervised physical exercise involving a standardized neuromuscular training program. As an evidence-based alternative, high–load (>70% 1RM) resistance training (HIRT) has shown positive rehabilitation effects in knee-OA but may not be tolerated in all patients (~25%) due to knee joint pain. However, low-load resistance training (20–40% 1RM) with concurrent partial blood-flow restriction (BFR) appears to produce effects similar to HIRT yet involving reduced joint pain during and after exercise. The aim is to examine the effect of low-load BFR training compared to SR on pain, thigh muscle mass and muscle function in adults with knee-OA. We hypothesize that 12 weeks of BFR will lead to superior improvements in pain, muscle mass and mechanical muscle function compared to SR. Methods and analysis 90 participants diagnosed with radiographic knee-OA will be randomized to either BFR or SR twice a week for 12 weeks. BFR will consist of two selected lower limb strength exercises performed with an inflated pneumatic occlusion cuff. Intervention procedures in SR consist of a full 8 weeks GLA:D course followed by 4 weeks of team group training. Primary outcome variable is the change in KOOS-Pain subscale from baseline to 12 weeks. Secondary outcome variables are changes in pain sensitivity, functional performance, muscle mass and mechanical muscle function. Intention-to-treat and per-protocol analyses will be conducted. One-way analysis of variance will be performed to evaluate between-group changes. Pre-to-post intervention comparisons will be analyzed using a mixed linear model. Regression analysis will be performed to evaluate potential associations between selected outcome variables.

Exercise Training Recommendations for Adults With and Without Chronic Disease to Improve Endothelial Health

The endothelium is the innermost layer of the blood vessels and is responsible for the production of chemicals that are used to regulate arterial diameter in response to changes in blood flow. Dysfunction of the endothelium is a key precursor for cardiovascular disease. However, exercise training may mitigate this dysfunction and promote endothelial health. Therefore, this infographic illustrates findings from an umbrella review (review of reviews; 10.1007/s40279-023-01837-w) that investigated the impact of any exercise training intervention (intervention) on adults with or without chronic disease (population), with, or without a comparator group (comparison), on endothelial function (outcome) using evidence from 27 reviews, including 19 meta-analyses (5464 unique participants). Overall, the included reviews provided evidence that the type of training to optimally improve endothelial function may vary based on disease condition. Specifically, the evidence suggests that healthy adults benefitted most from high intensity aerobic training and/or more frequent low-moderate resistance training. In addition, adults with type 2 diabetes benefitted most from low-intensity resistance or low-moderate aerobic exercise training, whereas those with cardiovascular conditions (i.e., heart transplant patients, peripheral artery disease, heart failure, hypertension, and cerebrovascular disease) should consider engaging in higher-intensity aerobic training to improve endothelial function, although may still need to consult a healthcare provider. Exercise training also improves endothelial function in other chronic conditions including cancer and autoimmune rheumatic disease, but the evidence is insufficient to provide specific guidelines. Although insufficient data exists to determine specific intervention characteristics (i.e., frequency, intensity, type, time), this information provides a high level of evidence to support exercise training, including aerobic, resistance, and combined training as effective strategies to improve endothelial-dependent vasodilatory function in adults. These findings should help guide the design of specific exercise programs or recommendations.

Muscle Mass and Muscle Strength Following 6 Weeks of Blood Flow Restriction Combined with Low-Intensity Strength Training in Overweight Adolescents

Background and Study purpose. Blood flow restriction training is a new training technique that involves low-intensity exercise and can generate physiological changes equivalent to high-intensity exercise. The aim of this study is to assess the impact of blood flow restriction in conjunction with low-intensity resistance exercise on muscle mass and muscle strength among overweight adolescents, in comparison to conventional resistance exercise. Materials and methods. The study involved two randomized groups: an experimental group, which performed 40% of one repetition maximum (1RM) resistance exercise combined with 60% of arterial occlusion pressure (AOP), and a traditional resistance exercise group, which performed 70% of 1RM resistance exercise. All participants underwent pre-test and post-test evaluations for body composition, 1RM, and muscle circumference. The training program lasted for six weeks and consisted of upper and lower body training, including exercises such as leg press, leg curl, arm curl, and arm extension. Results. The group that underwent low-load blood flow restriction (LLBFR) training showed a notable increase in muscle mass (p<0.049) as well as arm and leg circumference (p<0.047 and p<0.046, respectively) compared to before the training program, similar to the results of high-intensity resistance exercise. Conclusions. Combining blood flow restriction with low-intensity resistance training is a potentially effective approach to increase muscle size and strength, especially in overweight adolescents. Moreover, this type of training can decrease the amount of exercise load, making it a feasible option for individuals who may not tolerate high loads due to certain medical conditions or other limitations.

Effect of 12-Week Resistance Training with Blood Flow Restriction on Arterial Stiffness in Octogenarian People with Low Gait Speed: A Randomized Controlled Trial

Aim: Aging is associated with loss of muscle mass and strength. Low-Intensity Resistance Exercise with Moderate Blood-Flow Restriction (LIRE-BFR) improves these outcomes, but the long-term effect on arterial stiffness and safety in elderly people with low gait speed is unknown. Methods: This is a parallel, randomized controlled clinical study with 12 older adults (3 men; 9 women; 84.0 [76.0; 87.5] years old) who completed a 12-week training of traditional resistance exercise (TRE; n=6) or LIRE-BFR (n=6). All participants were evaluated at baseline and after 12 weeks by carotid-femoral aortic Pulse Wave Velocity (PWV). Results: After 12 weeks of interventions, PWV decreased in TRE group (-2.9 [-8.1; 2.4] m/s) and increased slightly in LIRE-BFR group (1.1 [-3.2; 5.3] m/s) but no differences were observed between the groups (p=0.21 for group; Hedge’s g: 0.52). Mean blood pressure was similar between TRE (86.2 [81.8; 90.9] to 85.8 [76.5; 96.3] mmHg) and LIRE-BFR (92.4 [82.1; 103.9] to 85.5 [79.2; 92.4] mmHg, p=0.462 for interaction). Gait speed increased significantly after 12 weeks in both groups (p<0.001 for time) with no differences between them (p=0.693 for groups). Conclusions: Compared to TRE, LIRE-BFR increased PWV slightly, while gait speed increased similarly in both training modalities. Larger clinical trials including elderly people with low gait speed are needed to determine the clinical impact of these findings.

Effect of Blood Flow Restriction in Low-Intensity Resistance Training of the Quadriceps Femoris Muscle on Joint Position Sense and Threshold to Detect Passive Motion in Patients with Knee Osteoarthritis

Backgrounds: The functional ability of knee OA (KOA) patients is mainly affected by muscle weakness and poor proprioception function. Quadriceps femoris strengthening exercises can improve proprioceptive function in patients with KOA, whereas low-intensity resistance exercises with Blood Flow Restriction have been shown to produce hypertrophy and increase muscle strength equivalent to high-intensity resistance exercises. However, prescriptions for exercise with BFR are still very diverse, and only a few studies show the effects of BFR training on proprioceptive function in patients with KOA. This study aims to determine the impact of BFR in LI-RT of the quadriceps femoris muscle on joint position sense and threshold to detect passive motion in patients with KOA. Methods: This randomized control trial study designed a clinical experiment with a before and after test. The research enrolled 28 people with KOA grades 2 and 3. The JPS and TTDPM, which reflect proprioceptive function, were measured before and after 6 weeks of exercise. This study's statistical analysis utilized the Monte Carlo test, independent t-test, and paired t-test. The effect size was noticed using Cohen's-d calculation to investigate the statistical influence of alterations further. The significance level was less than 0.05. Results: The mean age of the control group was 61.43 ± 5.70 years old, and the treatment group was 57.71 ± 5.25 years old. There were significant improvements in JPS and TTDPM results before and after training in each group (p < 0,05). There was no significant difference in JPS and TTDPM results between the two groups on the post-test on delta values (p> 0,05). Conclusions: The addition of BFR in LI-RT for 6 weeks did not affect JPS and TTDPM in patients with KOA.

Identification of Early Mobilization Interventions in Cardiovascular Disease Patients in Hospital

This study aims to categorize various early mobilization therapies in heart disease patients. The research method used is a systematic review by searching for articles using the Science Direct, PubMed, and Google Scholar databases. Key phrases included "early mobilization," "exercise training," and "cardiovascular disease and heart failure." The results showed that the interventions had 6MWT, CPET, progressive mobilization I, muscle breathing/inhalation training on day I, leg and limb exercises on the second and third days, ambulation, limb exercises, sitting, and walking. Around the bed, low-intensity resistance exercises in bed, and standing and tiptoe exercises on the floor beside the bed. Patients with acute heart failure often receive 20 to 40 minutes of therapy daily, including bedside exercises and a 50-step walk. In conclusion, there are still differences in time, scope, and implementation of early mobilization initiatives. However, mobilization therapy can be given to cardiac patients of all ages and is safe and practical. They help reduce re-hospitalization risk and improve a patient's VO2 and quality of life (QOL).
  
 Keywords: Heart Failure, Exercise, Early Mobilization, Exercise, Cardiovascular Disease

Effects of different modes and intensities of exercise on longevity proteins in middle-aged mouse skeletal muscle.

Physical exercise represents one of the most effective approaches to anti-aging. The goal of this study was to verify the effects of different modes and intensities of exercise on longevity proteins in the skeletal muscle in midlife. Middle-aged mice were trained in aerobic or resistance exercise for 8 weeks, and the changes in sirtuin 1 (SIRT1), adenosine monophosphate-activated kinase (AMPK), and mammalian target of rapamycin (mTOR) pathways in the skeletal muscle were evaluated by western blotting. Long-term exercise had no effects on skeletal muscle SIRT1 abundance, whereas high-intensity aerobic exercise increased AMPK phosphorylation and peroxisome proliferator-activated receptor-γcoactivator-1α (PGC-1α). Low-intensity resistance exercise facilitated Akt/mTOR/p70 ribosomal protein kinase S6 (p70S6K) signaling but did not induce muscle hypertrophy. Conversely, high-intensity resistance exercise stimulated muscle hypertrophy without phosphorylation of mTOR signaling-related proteins. These results suggest the importance of setting exercise modes and intensities for anti-aging in midlife.

Age and low intensity resistance exercise on exosome-like vesicle and skeletal muscle microRNA profiles.

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A home-based low-intensity resistance exercise programme with supervision for secondary sarcopenia in a patient with established rheumatoid arthritis: A case report.

Patients with established rheumatoid arthritis (RA) are at risk of developing secondary sarcopenia. Both pharmacological and exercise interventions are essential for treatment. However, for such patients, exercise loads may lead to the progression of joint destruction and worsening of pain. The purpose of this report was to assess the feasibility of a home-based, low-intensity resistance exercise programme. The case was a 70-year-old female patient with sarcopenia secondary to RA. She was diagnosed with RA at 57 years of age and began medication, maintaining remission of disease activity. However, she did not exercise habitually and was relatively inactive in her daily life. Furthermore, she had kinesiophobia associated with her RA-related symptoms. We suggested implementing a home-based low-intensity resistance exercise programme >3 months, with the goal of exercising the lower extremities daily. The patient was asked to self-monitor using an exercise diary and attend monthly outpatient visits for repeat counselling and feedback. As a result, she was able to perform the exercise programme safely with high compliance, improving her kinesiophobia as well as physical inactivity, although her skeletal muscle mass did not change. Regular exercise and increased physical activity may help prevent the onset of sarcopenia. These results demonstrate the feasibility of implementing our exercise programme and support its potential for preventing the progression of sarcopenia. While questions remain in terms of treating sarcopenia, we believe that our findings will lead to the establishment of an exercise programme for patients with sarcopenia secondary to established rheumatoid arthritis.

Acute cardiovascular responses to unilateral bicep curls with blood flow restriction

Background/ObjectivesA consensus on the acute cardiovascular responses to low intensity (LI) resistance exercise (RE) combined with blood flow restriction (BFR) has not yet been reached. This study was designed to compare acute cardiovascular responses to a single bout of LIRE, high intensity (HI) RE, and LIRE with BFR in physically active young males. MethodsParticipants completed 3 RE sessions in random order, where each session consists of 4 sets of unilateral dumbbell bicep curls. Cardiovascular hemodynamics were measured at baseline and right after each set of RE. ResultsAortic augmentation index (AIx) was significantly higher after set 2,3,4 of RE in LI + BFR session compared to LI session (P < 0.05). Brachial systolic blood pressure (SBP), heart rate (HR), brachial rate pressure product (RPP), and central RPP responses did not differ between LI and LI + BFR sessions (P > 0.05). HI session had a higher central SBP, brachial RPP, central RPP, and aortic AIx compared to LI session after each set of RE (P < 0.05), but not brachial SBP (P > 0.05). ConclusionsTaken together, this study showed that LIRE combined with BFR acutely augmented aortic stiffness, as also observed in HI session, but myocardial oxygen consumption was only higher in HI session when compared to LI session. Thus, although BFR did not exaggerate cardiovascular responses nor cause extra myocardial oxygen consumption, it should be prescribed with caution when control of acute aortic stiffening is necessary during RE.

Low-Intensity Resistance Exercise Based on Myofascial Chains Alters the Lower-Limb Tension and Improves Health Status in Female Individuals With Knee Osteoarthritis.

Low-intensity resistance exercise therapy (LIRET) based on myofascial chains, applied to both affected and nonlocal joints, is an effective method for knee osteoarthritis (OA) rehabilitation. This study applied LIRET in a comparison of prevalues and postvalues of lower-limb tension in female patients with knee OA and asymptomatic participants. Twenty-four female participants with knee OA and 20 asymptomatic women took part in a 3-month long application of LIRET. Participants' ankle passive torque and ankle range of motion in the sagittal plane were assessed with an isokinetic dynamometer. The collected values were used to estimate the sagittal-plane lower-limb tension. Compared with the asymptomatic group, participants with knee OA presented decreased maximum ankle dorsiflexion (P < .001), decreased ankle plantar flexion range (P = .023), ankle resting position more inclined to dorsiflexion (P = .017), increased ankle dorsiflexion stiffness (P = .005), and lower ankle plantar flexion stiffness (P = .034). After exercise intervention, the knee OA group self-reported less knee pain (P < .001), improved physical function (P < .001), increased maximum dorsiflexion (P = .021), and increased plantar flexion range (P < .001). While plantar flexion stiffness increased (P = .037), dorsiflexion stiffness decreased (P = .015) and ankle resting position moved toward dorsiflexion (P = .002). Results suggest possible decreased anterior leg tension and possible increased posterior leg tension in patients with knee OA. The results supported that knee OA patients present imbalanced myofascial tension of lower limbs. LIRET based on myofascial chains appears to decrease pain, and stiffness, and improve physical function of patients with knee OA and change their lower-limb tension.

Effects of prescribed low-intensity resistance exercise on prehypertension and other related factors in individuals living within Homa Bay Township, Western Kenya

Effects of prescribed low-intensity resistance exercise on prehypertension and other related factors in individuals living within Homa Bay Township, Western Kenya

ACUTE EFFECT OF BLOOD FLOW RESTRICTED RESISTANCE EXERCISE ON IRISIN AND SEX HORMONES

Purpose: The relationship between exercise and irisin and sex hormone release is unclear and is of interest to current research. This study aimed to investigate the acute effect of blood flow restricted (BFR) resistance exercise on irisin and sex hormones.&#x0D; Material and Methods: The study included healthy males over 18 years of age. Participants' physical activity levels were determined using International Physical Activity Questionnaire (IPAQ). Participants underwent body composition analysis and isotonic muscle strength measurement and were randomly divided into 3 groups: low-intensity (20% of 1-RM) resistance exercise with BFR, high-intensity (70% of 1-RM) resistance exercise without BFR, and a control group. Blood samples were obtained 15 minutes post-exercise to assess acute irisin, testosterone, and estrogen responses.&#x0D; Results: The study included 17 healthy males. The average age was 26.1±2.9 years, mean physical activity was 1259.2±1003.1 MET/week, and mean 1-RM max (as measured with isotonic muscle strength test) was 41.1±7.5 kg. The descriptive characteristics of the three groups were statistically similar (p&gt;0.05). The acute post-intervention irisin and sex hormone levels were not statistically different between the groups (p&gt;0.05).&#x0D; Conclusion: Acute changes in irisin and sex hormone levels were not statistically different for low-intensity BFR and high-intensity non-BFR exercise.

저강도 저항운동이 근감소증과 근감소성 비만인 고령여성의 Fullerton 상급균형능력과 균형자신감 검사에 미치는 영향

The purpose of this study was to investigate any changes in fullerton advanced balance(FAB) and balance efficacy scale(BES) in exercise intervention according to low-intensity resistance exercise for 16 weeks.BRThe subjects of the study were women aged 75 older living in Jin-gu, Busan, who were selected for sarcopenia and sarcopenic obesiry by diagnosis of sarcopenia (ASM/height, kg/h²; 5.38 or less) and sarcopenia obesity (ASM/weight, % ; 25.6% or less, % fat, % ; 30% or less). The participants were randomly assigned into 4 groups; sarcopenia resistance exercise group (S-RG; n=10, 75.7±3.0 yrs), sarcopenia control group (S-G; n=12, 77.2±2.8 yrs), sarcopenia obesity resistance exercise group (n=11, 76.5±3.3 yrs), sarcopenia obesity control group(n=12, 76.1±2.9 yrs).BRFor the statistical analysis, such as t-test, and Two-Way Repeated measures ANOVA was calculated using SPSS Version 27.0. As a result of this study, the interaction effect with the interaction effect was shown in the FAB and BES test.BRBased on the research results, the low intensity resistance exercise program using dumbbells seems to play an important role as an exercise program in improving balance ability and physical activity for elderly women with sarcopenia and sarcopenia obesity in community centers, elderly welfare facilities, and homes.

형태와 빈도에 따른 저강도 운동이 근감소증 비만 고령여성의 신체조성 변화에 관한 연구

The purpose of this study is to investigate any changes in body composition, such as muscle mass, %fat, and bone density, in exercise intervention according to the frequency of low-intensity aerobic exercise and resistance exercise for 16 weeks.BRThe subjects of the study were women aged over 75 yrs older living in Jin-gu, Busan, who were selected for sarcopenia by diagnosis of sarcopenia (ASM/weight, % ; 25.6% or less) and obesity (% fat, % ; 30% or over), Through drawing lots, a total of 104 people participated in the experiment, 29 people were eliminated from the pre-test measurement. And 29 people were excluded from the exercise intervention. The participants were randomly assigned into 5 groups; low intensity aerobic exercise 3 times per week group (n=10, 75.6±3.5 yrs), low intensity aerobic exercise 5 times per week group (n=8, 74.2±3.9 yrs), low intensity resistance exercise 3 times per week group (n=10, 75.4±3.7 yrs), low intensity resistance exercise 5 times per week group(n=8, 75.6±4.1 yrs) and a control group (n=10, 77.7±3.8 years).BRFor the statistical analysis, such as One-Way ANOVA, t-test, and Two-Way Repeated measures ANOVA was calculated using SPSS Version 22.0. To verify mean differences between the 5 groups, two-way repeated measures ANOVA was used.BRAs a result of the study, the interaction effect of the group and time period of %fat was shown (p＜.05), As a result of post-verification, A5-G and R5-G were higher than CG. In the change in the main effect of the time period within the group, there was a significant decrease in A5-G (p＜.001) and R5-G (p＜.01). And in the change in LBM, there were no interaction effects and main effects. And the interaction effect was not shown in the change in Total BMD, but a significant decrease was shown in R3-G (p＜.01) and CG (p＜.05) in the change in the main effect.BRBased on the research results, The interaction effect of aerobic exercise and resistance exercise 5 times a week was shown in the body fat rate change according to the low intensity form and frequency of exercise for 16 weeks in elderly women with muscle fat and bone density. However, through this study, there is a significant decrease in bone density in older women in the control group and aerobic exercise and resistance exercise group conducted three times a week, so it seems to play a role in suppressing fat and bone density due to aging.

Cardiometabolic Disease Risk in Normal Weight Obesity and Exercise Interventions for Proactive Prevention

PURPOSE: Normal weight obesity (NWO) is characterized by a normal body mass index but a high body fat mass percentage and low skeletal muscle mass, thereby increasing the risk of cardiometabolic dysfunction and morbidity. However, the effects of exercise intervention in reducing the risk of cardiometabolic disease in NWO have not been fully elucidated. Therefore, this review aimed to summarize the potential cardiometabolic disease risk and to provide implications of exercise interventions for the proactive prevention of cardiometabolic disease risk in NWO.METHODS: We searched and summarized the literature on the cardiometabolic risk factors in NWO. In addition, we summarized literature investigating the effects of exercise intervention on the cardiometabolic risk factors in NWO. We performed the literature search using PubMed, Web of Science, and Google Scholar databases.RESULTS: NWO was associated with increased visceral fat, ectopic fat, oxidative stress, inflammatory cytokines, insulin resistance, dyslipidemia, and subclinical atherosclerosis compared with normal weight lean. NWO requires exercise interventions that induce alterations in body composition, such as decreased body fat percentage and increased muscle mass. Resistance exercise (RE) and high-intensity interval exercise (HIIE) can improve lipid components and alter body composition in NWO. In addition, low-intensity blood flow restriction resistance exercise (BFR-RE) may enhance muscular strength and anaerobic power in NWO.CONCLUSIONS: The cardiometabolic disease risk is increased in NWO. We suggest that exercise interventions (RE, HIIE, and BFR-RE) may effectively prevent cardiometabolic disease risk and alter body composition in NWO. As this has potential implications for exercise interventions in NWO, further investigations are needed to find the optimal exercise for proactive prevention of cardiometabolic risk in NWO.

Effects of Quercetin Glycoside Supplementation Combined With Low-Intensity Resistance Training on Muscle Quantity and Stiffness: A Randomized, Controlled Trial.

ObjectiveAging of skeletal muscle is characterized not only by a decrease of muscle quantity but also by changes in muscle quality, such as an increase in muscle stiffness. The present study aimed to investigate the effects of supplementation with quercetin glycosides (QGs), well-known polyphenolic flavonoids, combined with resistance exercise on muscle quantity and stiffness.Materials and MethodsA randomized, controlled trial was conducted in community-dwelling, Japanese people aged 50–74 years who were randomly allocated to exercise with placebo or 200 or 500 mg of QG supplementation. All participants performed low-intensity resistance training mainly targeting thigh muscles with 40% of 1-repetition maximum, 3 days per week for 24 weeks. Muscle cross-sectional area (CSA), lean mass, and vastus lateralis (VL) muscle stiffness were measured before and after the 24-week intervention.ResultsForty-eight subjects completed the 24-week intervention. There were no significant group × time interactions in thigh CSA for primary outcome, as well as lean mass. VL muscle stiffness in the stretched position was significantly lower in both the 200 mg and 500 mg QG groups than in the placebo group after the 24-week intervention (p < 0.05). No significant correlation was observed between changes of VL muscle CSA and stiffness during the 24-week intervention.ConclusionQuercetin glycoside supplementation combined with low-intensity resistance exercise improved passive muscle stiffness independently of muscle quantity.Clinical Trial Registration[www.umin.ac.jp/ctr/], identifier [UMIN000037633].

Neuromuscular Impact of Acute Hypertrophic Resistance Loading With and Without Blood-Flow Restriction

Exploring acute neuromuscular fatigue induced by different modalities of resistance exercise would help understand the adaptation subsequent to specific training programs. Therefore, we investigated the acute impact of high-intensity and low-intensity blood flow-restricted resistance exercise on the development of explosive torque throughout the torque-time curve. Seventeen healthy, young participants were included in a randomized, counterbalanced within-subjects design study, in which participants underwent two experimental conditions, separated by a 1-wk period. Low-intensity blood-flow restricted exercise and high-intensity resistance exercise were performed using dynamic elbow flexion at 20 and 75% of 1 repetition maximum, respectively. Maximal voluntary contraction (MVC) and the sequential rate of torque development (absolute and relative) were measured before and after exercise. Both protocols elicited a similar decrement in MVC (~ 25%) and in the peak rate of torque development after exercise (~ 45%). The absolute rate of torque development (0-50 and 50-100 ms) was also reduced (p<0.05) similarly between conditions. After normalizing torque values to MVC, this was only sustained for the rate of torque development 0-50ms (p<0.05). We found that both exercise protocols induced similar acute attenuation of the absolute rate of torque development up to the first 100 ms of MVC. We also demonstrated that the reduction in the rate of torque development between 50-100ms (in both protocols) was largely explained by an acute deficit in muscle strength post-exercise. Conversely, the impact of each protocol on the first 50ms of muscle torque did not depend on lower levels of muscle strength after exercise.