Moderators of Resistance Training Effects in Healthy Young Women: A Systematic Review and Meta-analysis.

ABSTRACT: Molinari, T, Radaelli, R, Rech, A, Brusco, CM, Markarian, AM, and Lopez, P. Moderators of resistance training effects in healthy young women: A systematic review and meta-analysis. J Strength Cond Res 38(4): 804-814, 2024-To systematically review and analyze the effects of resistance-based exercise programs and potential moderators of change in body fat percentage, whole-body fat and lean mass, muscle hypertrophy, muscle strength, and muscle power/rapid force in healthy young women (between 18 and 35 years). A systematic search was undertaken in 7 databases from inception to May 2022. Eligible randomized controlled trials examined the effects of resistance-based exercise programs on outcomes of interest in healthy young women. Meta-analysis was undertaken with a 3-level mixed-effects model. Associations between standardized mean difference (SMD) and potential moderators (number of sessions, weekly volume, and intensity) were tested by meta-regression models. Statistical significance was set at an α level of 0.05, whereas an α level of 0.05-0.10 was also considered for potential moderators of resistance training effects. Forty articles ( n = 1,312) were included. Resistance-based exercise programs resulted in a significant improvement of 0.4 SMD (95% confidence intervals [95% CI]: 0.2 to 0.5, p < 0.001) in lean mass/muscle hypertrophy and 1.2 SMD (95% CI: 0.9 to 1.5, p < 0.001) in muscle strength. A higher number of sessions was associated with changes in lean mass/muscle hypertrophy ( ß = 0.01 ± 0.00, p = 0.009), whereas a higher weekly volume approached statistical significance to moderate changes in muscle strength ( ß = 0.01 ± 0.01, p = 0.053). Body fat percentage (-0.4 SMD, 95% CI: -0.6 to -0.1, p = 0.006) and muscle power/rapid force (0.6 SMD, 95% CI: 0.2 to 1.1, p = 0.011) were significantly improved. In conclusion, a higher resistance training volume was associated with greater improvements in lean mass/muscle hypertrophy, muscle strength, and body fat percentage, whereas muscle power/rapid force improvements were observed irrespective of prescription characteristics. These findings may help in designing resistance training programs for muscle hypertrophy, strength and power, and body fat percentage in healthy women.

Effects of Traditional and Vascular Restricted Strength Training Program With Equalized Volume on Isometric and Dynamic Strength, Muscle Thickness, Electromyographic Activity, and Endothelial Function Adaptations in Young Adults.

Ramis, TR, Muller, CHdL, Boeno, FP, Teixeira, BC, Rech, A, Pompermayer, MG, Medeiros, NdS, Oliveira, ÁRd, Pinto, RS, and Ribeiro, JL. Effects of traditional and vascular restricted strength training program with equalized volume on isometric and dynamic strength, muscle thickness, electromyographic activity, and endothelial function adaptations in young adults. J Strength Cond Res 34(3): 689-698, 2020-The purpose of the study was to evaluate and compare the acute and chronic effects of partial vascular occlusion training in young, physically active adults. Neuromuscular, morphological, and endothelial function responses were compared between high-intensity resistance training (HI-RT) and low-intensity resistance training with partial vascular occlusion (LI-BFR), despite the same training volume. The 28 subjects (age, 23.96 ± 2.67 years) were randomly assigned into 2 groups: LI-BFR (n = 15) and HI-RT (n = 13). Both groups performed unilateral exercise of elbow flexion (EF) and knee extension (KE) 3 times per week for 8 weeks. This study was approved by the ethics committee. Flow-mediated dilation showed a significant difference in baseline and post-training in the LI-BFR group (4.44 ± 0.51 vs. 6.35 ± 2.08 mm, respectively). For nitrite/nitrate concentrations only, there was a significant difference when comparing pre- and post-acute exercise in both groups. The torque and rep. Sixty percent 1 repetition maximum had improvements in both groups. There were differences between groups only in isometric delta EF and isokinetic delta KE (EF 3.42 ± 5.09 and 9.61 ± 7.52 N·m; KE 12.78 ± 25.61 and 42.69 ± 35.68 N·m; LI-BFR and HI-RT groups, respectively). There was a significant increase of muscle thickness in both groups. An increase of both isokinetic and isometric electromyography (EMG) of biceps of the HI-RT group was observed. The same was observed for the LI-BFR group regarding isokinetic and isometric EMG of vastus lateralis. Thus, in addition to strength and hypertrophy gains, this study also shows benefits related to vascular function. For practical applications, this study demonstrates a clinical importance of LI-BFR training as an alternative methodology.

Benefits of resistance training in physically frail elderly: a systematic review.

AIM: Exercise is one of the most important components in frailty prevention and treatment. Therefore, we systematically reviewed the effect of resistance training (RT) alone or combined with multimodal exercise intervention on muscle hypertrophy, maximal strength, power output, functional performance, and falls incidence in physically frail elderly. METHODS: MEDLINE, Cochrane CENTRAL, PEDro, and SPORTDiscus databases were searched from 2005 to 2017. Studies must have mentioned the effects of RT (i.e., included or not in multimodal training) on at least one of the following parameters: muscle mass, muscle strength, muscle power, functional capacity, and risk of falls in frail elderly. RESULTS: The initial search identified 371 studies and 16 were used for qualitative analysis for describing the effect of strength training performed alone or in a multimodal exercise intervention. We observed that RT alone or in a multimodal training may induce increases of 6.6-37% in maximal strength; 3.4-7.5% in muscle mass, 8.2% in muscle power, 4.7-58.1% in functional capacity and risk of falls, although some studies did not show enhancements. CONCLUSION: Frequency of 1-6 sessions per week, training volume of 1-3 sets of 6-15 repetitions and intensity of 30-70%1-RM promoted significant enhancements on muscle strength, muscle power, and functional outcomes. Therefore, in agreement with previous studies, we suggest that supervised and controlled RT represents an effective intervention in frailty treatment.

Echo intensity independently predicts functionality in sedentary older men.

INTRODUCTION: The aim of this study was to examine the associations between quadriceps muscle functionality features in nonactive older men to determine predictors of functional performance. METHODS: Quadriceps functional parameters, including quadriceps echo intensity (QEI), rate of torque development (RTD), and the 30 s sit-to-stand test (30SS), were assessed in 50 healthy sedentary older men (66 ± 5.4 years). RTD/QEI ratios were also calculated to identify the best predictor of functional performance. RESULTS: 30SS performance was associated with RTD, muscle thickness, RTD-50/QEI, RTD-100/QEI, RTD-50/QEI/WBM, and RTD-100/QEI/WBM. A multiple stepwise linear regression demonstrated that QEI was the best single predictor of functional performance, explaining ∼30% of the 30SS variance. CONCLUSIONS: These results indicate that QEI was the strongest contributor to functionality of nonactive older men, suggesting that QEI may be an alternative tool for screening of muscle impairment that leads to decreased functional performance in this population. Muscle Nerve 55: 9-15, 2017.

Neuromuscular Adaptations to Unilateral vs. Bilateral Strength Training in Women.

Botton, CE, Radaelli, R, Wilhelm, EN, Rech, A, Brown, LE, and Pinto, RS. Neuromuscular adaptations to unilateral vs. bilateral strength training in women. J Strength Cond Res 30(7): 1924-1932, 2016-Considering the bilateral deficit, the sum of forces produced by each limb in a unilateral condition is generally greater than that produced by them in a bilateral condition. Therefore, it can be speculated that performing unilateral strength exercises may allow greater training workloads and subsequently greater neuromuscular adaptations when compared with bilateral training. Hence, the purpose of this study was to compare neuromuscular adaptations with unilateral vs. bilateral training in the knee extensor muscles. Forty-three recreationally active young women were allocated to a control, unilateral (UG) or bilateral (BG) training group, which performed 2 times strength training sessions a week for 12 weeks. Knee extension one repetition maximum (1RM), maximal isometric strength, muscle electrical activity, and muscle thickness were obtained before and after the study period. Muscle strength was measured in unilateral (right + left) and bilateral tests. Both UG and BG increased similarly their unilateral 1RM (33.3 ± 14.3% vs. 24.6 ± 11.9%, respectively), bilateral 1RM (20.3 ± 6.8% vs. 28.5 ± 12.3%, respectively), and isometric strength (14.7 ± 11.3% vs. 13.1 ± 12.5%, respectively). The UG demonstrated greater unilateral isometric strength increase than the BG (21.4 ± 10.5% vs. 10.3 ± 11.1%, respectively) and only the UG increased muscle electrical activity. Muscle thickness increased similarly for both training groups. Neither group exhibited pretesting 1RM bilateral deficit values, but at post-testing, UG showed a significant bilateral deficit (-6.5 ± 7.8%) whereas BG showed a significant bilateral facilitation (5.9 ± 9.0%). Thus, performing unilateral or bilateral exercises was not a decisive factor for improving morphological adaptations and bilateral muscle strength in untrained women. Unilateral training, however, potentiate unilateral specific strength gains.

The effects of strength, aerobic, and concurrent exercise on skeletal muscle damage in rats.

INTRODUCTION: In this study we examined oxidative stress and skeletal muscle damage resulting from acute strength, aerobic, or concurrent exercise in rats. METHODS: The animals were divided into control (C), strength (SE), aerobic (AE), and combined (CE) exercise groups. They were euthanized at 3 different time-points (6, 24, and 48 h) after acute exercise. RESULTS: SE exercise rats had increased dichlorofluorescein oxidation at 6 h post-exercise and decreased superoxide dismutase activity at all time-points. Glutathione peroxidase activity and sulfhydryl levels were increased in the AE group at 48 h post-exercise. Serum lactate dehydrogenase activity was increased in the SE and CE groups at 24 h and in the AE group at 48 h. Echo intensity was elevated at 24 h for all groups. CONCLUSIONS: Forty-eight hours was sufficient for complete recovery from oxidative stress and muscle damage in the SE and CE groups, but not in the AE group.

Does High-Velocity Resistance Exercise Elicit Greater Physical Function Benefits Than Traditional Resistance Exercise in Older Adults? A Systematic Review and Network Meta-Analysis of 79 Trials.

BACKGROUND: A systematic review and network meta-analysis was undertaken to examine the effectiveness of different modes of resistance exercise velocity in fast walking speed, timed-up and go, 5-times sit-to-stand, 30-second sit-to-stand, and 6-minute walking tests in older adults. METHODS: CINAHL, Embase, LILACS, PubMed, Scielo, SPORTDiscus, and Web of Science databases were searched up to February 2022. Eligible randomized trials examined the effects of supervised high-velocity or traditional resistance exercise in older adults (ie, ≥60 years). The primary outcome for this review was physical function measured by fast walking speed, timed-up and go, 5-times sit-to-stand, 30-second sit-to-stand, and 6-minute walking tests, while maximal muscle power and muscle strength were secondary. A random-effects network meta-analysis was undertaken to examine the effects of different resistance exercise interventions. RESULTS: Eighty articles describing 79 trials (n = 3 575) were included. High-velocity resistance exercise was the most effective for improving fast walking speed (standardized mean difference [SMD] -0.44, 95% confidence interval [CI]: 0.00 to 0.87), timed-up and go (SMD -0.76, 95% CI: -1.05 to -0.47), and 5-times sit-to-stand (SMD -0.74, 95% CI: -1.20 to -0.27), while traditional resistance exercise was the most effective for 30-second sit-to-stand (SMD 1.01, 95% CI: 0.68 to 1.34) and 6-minute walking (SMD 0.68, 95% CI: 0.34 to 1.03). CONCLUSION: Our study provides evidence that resistance exercise velocity effects are specific in older adults, as evidenced by physical function test dependence. We suggest that prescriptions based on the velocity of contraction should be individualized to address the specific functional needs of participants.

Ω3-Polyunsaturated fatty acids prevent lipoperoxidation, modulate antioxidant enzymes, and reduce lipid content but do not alter glycogen metabolism in the livers of diabetic rats fed on a high fat thermolyzed diet.

Ω3-Polyunsaturated fatty acids (Ω3-PUFAs) are known to act as hypolipidaemics, but the literature is unclear about the effects that Ω3-PUFAs have on oxidative stress in obese and diabetic patients. In this study, our aim was to investigate the effects of Ω3-PUFAs on oxidative stress, including antioxidant enzyme activity and hepatic lipid and glycogen metabolism in the livers of diabetic and non-diabetic rats fed on a high fat thermolyzed diet. Rats were divided into six groups: (1) the control group (C), (2) the control diabetic group (D), (3) the high fat thermolyzed diet group (HFTD), which were fed a diet that was enriched in fat that was heated for 60 min at 180°C, (4) the high fat thermolyzed diet diabetic group (D + HFTD), (5) the high fat thermolyzed diet + Ω3 polyunsaturated fatty acid group (HFTD + Ω3), and (6) the high fat thermolyzed diet + Ω3 polyunsaturated fatty acid diabetic group (D + HFTD + Ω3). The most important finding of this study was that Ω3-PUFAs are able to reduce triglycerides, non-esterified fatty acid, lipoperoxidation levels, advanced glycation end products, SOD/CAT enzymatic ratio, and CAT immunocontent and increase SOD2 levels in the livers of diabetic rats fed with a HFTD. However, Ω3-PUFAs did not alter the observed levels of protein damage, blood glucose, or glycogen metabolism in the liver. These findings suggest that Ω3-PUFAs may represent an important auxiliary adjuvant in combating some diseases like diabetes mellitus, insulin resistance, and non-alcoholic fatty liver disease.

Resistance training effectiveness on body composition and body weight outcomes in individuals with overweight and obesity across the lifespan: A systematic review and meta-analysis.

To systematically review and analyze the effects of resistance-based exercise programs on body composition, regional adiposity, and body weight in individuals with overweight/obesity across the lifespan. Using PRISMA guidelines, randomized controlled trials were searched in nine electronic databases up to December 2020. Meta-analyses were performed using random-effects model. One-hundred sixteen articles describing 114 trials (n = 4184 participants) were included. Interventions involving resistance training and caloric restriction were the most effective for reducing body fat percentage (ES = -3.8%, 95% CI: -4.7 to -2.9%, p < 0.001) and whole-body fat mass (ES = -5.3 kg, 95% CI: -7.2 to -3.5 kg, p < 0.001) compared with groups without intervention. Significant results were also observed following combined resistance and aerobic exercise (ES = -2.3% and -1.4 kg, p < 0.001) and resistance training alone (ES = -1.6% and -1.0 kg, p < 0.001) compared with no training controls. Resistance training alone was the most effective for increasing lean mass compared with no training controls (ES = 0.8 kg, 95% CI: 0.6 to 1.0 kg, p < 0.001), whereas lean mass was maintained following interventions involving resistance training and caloric restriction (ES = ~ - 0.3 kg, p = 0.550-0.727). Results were consistently observed across age and sex groups (p = 0.001-0.011). Reductions in regional adiposity and body weight measures were also observed following combined resistance and aerobic exercise and programs including caloric restriction (p < 0.001). In conclusion, this study provides evidence that resistance-based exercise programs are effective and should be considered within any multicomponent therapy program when caloric restriction is utilized in individuals with overweight or obesity.

Moderators of Resistance Training Effects in Overweight and Obese Adults: A Systematic Review and Meta-analysis.

PURPOSE: This study aimed to analyze whether the effects of resistance exercise on whole-body fat and lean mass are moderated by exercise dosage (i.e., duration, volume, and intensity), age, body mass index, baseline values, assessment methods, and prescription of aerobic exercise and caloric restriction in overweight/obese adults. METHODS: A systematic search was undertaken in 11 databases from inception to December 2020, with an updated search undertaken in April 2022. Eligible randomized controlled trials examined the effects of resistance-based exercise programs on whole-body fat mass and lean mass in adults who were overweight or obese. Meta-analysis was undertaken with a random-effects model. Associations between mean differences and potential moderators were tested by meta-regression models. RESULTS: Sixty-seven articles describing 65 trials ( n = 2537) were included. Resistance-based exercise programs resulted in a significant change of -1.6 kg (95% confidence interval [CI] = -1.9 to -1.3 kg, P < 0.001) in whole-body fat mass and +0.8 kg (95% CI = 0.6 to 0.9 kg, P < 0.001) in lean mass. Male participants experienced greater effects than females ( P < 0.001), whereas those presenting with higher levels of fat mass at baseline experienced greater reductions in this outcome ( P = 0.084). For lean mass, younger adults experienced greater improvements compared with older participants ( P = 0.009), whereas programs comprising resistance exercise and caloric restriction resulted in significant reductions in lean mass ( P = 0.035). Resistance exercise dosage or prescription of aerobic exercise was not associated with change in these outcomes. CONCLUSIONS: Resistance-based programs improve body composition regardless of the resistance exercise dosage or aerobic component prescribed in adults who are overweight or obese. In addition, subgroups based on demographic characteristics, baseline levels, and presence of caloric restriction may present with more favorable responses in body composition.

The effects of periodized concurrent and aerobic training on oxidative stress parameters, endothelial function and immune response in sedentary male individuals of middle age.

The vascular endothelium plays a key role in arterial wall homeostasis by preventing atherosclerotic plaque formation. A primary causal factor of endothelial dysfunction is the reactive oxygen species. Aerobic exercise is ascribed as an important adjuvant therapy in endothelium-dependent cardiovascular disease. However, little is known about the effects of concurrent (aerobic + strength) training on that. For a comparison of the effects of aerobic and concurrent physical training on endothelial function, oxidative stress parameters and the immunoinflammatory activity of monocytes/macrophages, 20 adult male volunteers of middle age were divided into a concurrent training (CT) programme group and an aerobic training group. The glutathione disulphide to glutathione ratio (GSSG/GSH) and plasma lipoperoxide (LPO) levels, as well as flow-mediated dilation (FMD), monocyte/macrophage functional activity (zymosan phagocytosis), body lipid profiles, aerobic capacity (maximal oxygen uptake) and strength parameters (one-repetition maximum test), were measured before and after the exercise training programmes. The CT exhibited reduced acute effects of exercise on the GSSG/GSH ratio, plasma LPO levels and zymosan phagocytosis. The CT also displayed improved lipid profiles, glycaemic control, maximal oxygen uptake and one-repetition maximum test values. In both the aerobic training and the CT, training improved the acute responses to exercise, as inferred from a decrease in the GSSG/GSH ratios. The aerobic sessions did not alter basal levels of plasma LPO or macrophage phagocytic activity but improved FMD values as well as lipid profiles and glycaemic control. In summary, both training programmes improve systemic redox status and antioxidant defences. However, the aerobic training was more efficient in improving FMD in the individuals studied.

Effects of an 8-week resistance training intervention on plantar flexor muscle quality and functional capacity in older women: A randomised controlled trial.

The present study examined 8 weeks of resistance training and its effects on muscle quality measures, plantar flexor muscle strength, muscle thickness and functional capacity in older women. Moreover, we tested if changes in muscle quality were associated with functional capacity. Twenty-four older women (66.3 ± 5.8 years; 69.0 ± 3.0 kg; 25.3 ± 1.4 kg·m-2) were recruited to the study. After completion of the baseline assessment, participants were randomly assigned to either the resistance training (RET, n = 12) or an active control group (CTR, n = 12). Muscle quality was evaluated through muscle echo intensity (MQEI) and specific tension (MQST). Muscle thickness, unilateral plantar flexor muscle strength and functional tests were evaluated at baseline and after the training period. After 8 weeks, both MQEI and MQST did not respond to the intervention. Furthermore, significant changes in stair climb performance (P < 0.05) were not associated with plantar flexor-derived muscle quality (P > 0.05). Finally, significant gains in muscle hypertrophy were observed in the RET group (P < 0.01), while muscle strength failed to change significantly (P > 0.05). In conclusion, a resistance training program provided significant benefits in the stair climb test, unrelated to plantar flexor-derived muscle quality measures as previously demonstrated in quadriceps femoris.

Effects of short-term resistance training on endothelial function and inflammation markers in elderly patients with type 2 diabetes: A randomized controlled trial.

PURPOSE: To evaluate the effects of 12-weeks of strength training on endothelial function and inflammatory markers in elderly individuals with T2DM. METHODS: Forty-four elderly patients with T2DM were screened for participation. After completion of the baseline assessment, participants were randomly assigned to either the resistance training group (RT) or an active control group (AC). Inflammatory (TNF-α, IL-6, IL-1ß, IL-10 and CRP) and blood lipid profiles, glycated hemoglobin, basal artery diameter and flow mediated dilation were evaluated before and after the intervention. Comparisons between groups were obtained from the generalized estimation equation and all tests were two-tailed and the alpha level for significance set at 0.05. RESULTS: TNF-α and IL-1ß were decreased in both groups, while no interactions were found for flow mediated dilation and basal artery diameter. No significant differences were found for blood lipid profile and glycated hemoglobin for both groups after the intervention period. CONCLUSIONS: No significant changes were found between the RT and AC groups, regarding inflammatory profile and endothelial function, which does not prove the superiority of this intervention model in the studied period.

Muscle quality and functionality in older women improve similarly with muscle power training using one or three sets.

The present study compared the effects of 12 weeks of muscle power training performing one or three sets on muscle quality assessed by echo intensity (MQEI) and index (MQindex), muscle power-related outcomes, and functional capacity in older women. Participants were randomly assigned into two groups: 1SET (n = 13) and 3SET (n = 13). Lower limb muscle power and vertical jump height were measured during a countermovement jump, maximal rate of torque development (MRTD), and root mean square (RMS) of electromyography signals and rate of rise (RER) of quadriceps maximal electromyography activation during unilateral knee extension at 0-50 and 0-200 ms, MQEI, MQindex (absolute muscle power/MQEI, and MRTD/MQEI) and functionally in both groups using timed-up-and-go were evaluated before and after training. There were significant and similar (p < 0.05) increases in muscle power, vertical jump height, MQEI, MQindex, and functionally (p ≤ 0.0001) in both groups. In contrast, MRTD increased only in 1SET (p ≤ 0.001), and the RMS0-200 and RER0-50 increased for 3SET only (p ≤ 0.05), with no difference between groups (p > 0.05). In conclusion, similar neuromuscular adaptations and improvements in the functional performance occurred in both groups.

Effects of resistance training on neuromuscular parameters in elderly with type 2 diabetes mellitus: A randomized clinical trial.

This study is a randomized controlled clinical trial that verified the resistance training efficacy on neuromuscular parameters, with muscle quality as primary outcome. Forty-four elderly with diabetes type 2 (69.7 ±â€¯6.9 years; 26 men) were randomly allocated to a 12-weeks resistance training group (RTG, 3 times a week), or an active control group with stretching classes (CG, once a week). Primary and secondary outcomes were assessed at baseline and after 12 weeks, as follow: quadriceps muscle thickness and rectus femoris muscle quality, maximal knee extension strength, rapid strength, functional performance, visceral adipose tissue, glycemic control, lipid profile and quality of life. Generalized estimating equations were used to analyses based on intention-to-treat and per-protocol approaches, which showed the same results. Among all outcomes measured there were improvements in the knee extension strength (P < 0.001) and quadriceps muscle thickness (P < 0.001) for RTG. The muscle quality did not improve for both groups (P = 0.98). For the secondary outcomes there were no improvements for functional performance, rapid strength, glycemic control, quality of life, visceral adipose tissue and lipid profile in both groups, with exception of triglyceride level reduction for RTG (P = 0.04).The resistance training program is an efficacious strategy for improve the neuromuscular health in elderly with T2DM, considering increases in lower limb strength and muscle mass, but the same was not found for muscle quality, rapid strength, functional performance and quality of life. Furthermore, the training program did not induce significant reduction in glycated hemoglobin values of patients who already had suitable glycemic control.

Higher muscle power training volume is not determinant for the magnitude of neuromuscular improvements in elderly women.

The aim of this study was to compare the effects of 12 weeks of muscle power training using one- and three-sets on neuromuscular adaptations in elderly women. Twenty six healthy elderly women were randomly assigned into two groups: one-set (n = 13) and three-sets (n = 13). Maximal dynamic and isometric strength, rapid force assessed as absolute and normalized rate of force development (RTD) and contractile impulse during unilateral leg knee extension at 0-50 and 0-200 ms, overall quadriceps muscle thickness, muscle power during a countermovement jump (CMJ), and functional performance using time-up-and-go and the timed stair climb tests were evaluated before and after training. After 12 weeks, one-set and three-sets groups exhibited significant (p ≤ 0.05) and comparable increases in dynamic and isometric strength, absolute RTD and contractile impulse at 0-50 and at 0-200 ms and in the performance of both functional tests. No significant differences between groups were evident for any measured parameters (p > 0.05). Furthermore, the normalized RTD did not increase for any group (p > 0.05). Over 12 weeks, the muscle power training performing one- or three-sets induced alike improvements in muscle function, mass and functionally. These evidences suggest that a low training volume is able to induce significant improvements in age-related neuromuscular changes.

Heat-induced extracellular HSP72 release is blunted in elderly diabetic people compared with healthy middle-aged and older adults, but it is partially restored by resistance training.

Recent evidence suggests that the anti-inflammatory heat shock response (HSR) is reduced in aging and diabetes. In this study we compared HSR between healthy middle-aged adults, healthy elderly and type 2 diabetic (T2DM) elderly, and tested whether resistance training (RT) could improve the HSR in T2DM group. Thirty sedentary participants volunteered for this study. HSR (assessed as the capacity to export HSP72 during heat stress) was measured in the blood and compared between the groups. HSR was similar between healthy middle-aged and healthy elderly volunteers, but diminished in elderly T2DM (p < 0.001). Hence, T2DM subjects (n = 12) were submitted to a 12-week RT program, because exercise is a physiological HSR inducer. HSR, cytokines, metabolic parameters and visceral adipose tissue (VAT) were measured before and after the RT. Remarkably, VAT was negatively correlated with HSR (r = - 0.49, p < 0.01) while RT improved the HSR and reduced inflammation [TNF-α: from 51.5 ±â€¯9 to 40.7 ±â€¯4 pg/mL and TNF-α/IL-10 ratio: from 1.55 ±â€¯0.3 to 1.16 ±â€¯0.2 (p < 0.001)], without affecting other parameters. All together, these findings confirm the hypothesis that the anti-inflammatory HSR is depressed in elderly diabetic people, but can be partially restored by RT.

Sulforaphane ameliorates the insulin responsiveness and the lipid profile but does not alter the antioxidant response in diabetic rats.

Diabetes is one of the most prevalent chronic non-communicable diseases and is characterized by hyperglycemia and increased oxidative stress. These two alterations are also responsible for the main diabetic complications: cardiovascular disease, retinopathy, nephropathy and peripheral neuropathy. Diabetes progression is governed by pancreatic ß-cell failure, and recent studies showed that sulforaphane (SFN) might be able to prevent this change, preserving insulin production. Consequently, our goal was to test the effects of SFN on metabolic parameters related to diabetic complications and antioxidant defenses (superoxide dismutase, catalase and sulfhydryl groups) in the pancreas, liver and kidney of non-diabetic and diabetic rats. Male Wistar rats were treated with water or 0.5 mg kg(-1) SFN i.p. for 21 days after diabetes induction. In diabetic animals treated with SFN, the serum levels of total cholesterol, non-HDL cholesterol and triacylglycerols were similar to those of non-diabetic animals, and the insulin responsiveness was higher than that of the diabetic animals that did not receive the compound. No effect of SFN on the superoxide dismutase and catalase activity or sulfhydryl groups was observed in the pancreas, liver or kidney of the treated animals. We conclude that SFN ameliorates some features of clinical diabetic complications particularly the lipid profile and insulin responsiveness, but it does not modulate the antioxidant response induced by superoxide dismutase, catalase and sulfhydryl groups in the evaluated organs.

Effect of exercise intensity on postprandial lipemia, markers of oxidative stress, and endothelial function after a high-fat meal.

The aim of this study was to compare the effects of 2 different exercise intensities on postprandial lipemia, oxidative stress markers, and endothelial function after a high-fat meal (HFM). Eleven young men completed 2-day trials in 3 conditions: rest, moderate-intensity exercise (MI-Exercise) and heavy-intensity exercise (HI-Exercise). Subjects performed an exercise bout or no exercise (Rest) on the evening of day 1. On the morning of day 2, an HFM was provided. Blood was sampled at fasting (0 h) and every hour from 1 to 5 h during the postprandial period for triacylglycerol (TAG), thiobarbituric acid reactive substance (TBARS), and nitrite/nitrate (NOx) concentrations. Flow-mediated dilatation (FMD) was also analyzed. TAG concentrations were reduced in exercise conditions compared with Rest during the postprandial period (P < 0.004). TAG incremental area under the curve (iAUC) was smaller after HI-Exercise compared with Rest (P = 0.012). TBARS concentrations were reduced in MI-Exercise compared with Rest (P < 0.041). FMD was higher in exercise conditions than Rest at 0 h (P < 0.02) and NOx concentrations were enhanced in MI-Exercise compared with Rest at 0 h (P < 0.01). These results suggest that acute exercise can reduce lipemia after an HFM. However, HI-Exercise showed to be more effective in reducing iAUC TAG, which might suggest higher protection against postprandial TAG enhancement. Conversely, MI-Exercise can be beneficial to attenuate the susceptibility of oxidative damage induced by an HFM and to increase endothelial function in the fasted state compared with Rest.

Cerebral Ketone Body Oxidation Is Facilitated by a High Fat Diet Enriched with Advanced Glycation End Products in Normal and Diabetic Rats.

Diabetes mellitus (DM) causes important modifications in the availability and use of different energy substrates in various organs and tissues. Similarly, dietary manipulations such as high fat diets also affect systemic energy metabolism. However, how the brain adapts to these situations remains unclear. To investigate these issues, control and alloxan-induced type I diabetic rats were fed either a standard or a high fat diet enriched with advanced glycation end products (AGEs) (HAGE diet). The HAGE diet increased their levels of blood ketone bodies, and this effect was exacerbated by DM induction. To determine the effects of diet and/or DM induction on key cerebral bioenergetic parameters, both ketone bodies (ß-hydroxybutyric acid) and lactate oxidation were measured. In parallel, the expression of Monocarboxylate Transporter 1 (MCT1) and 2 (MCT2) isoforms in hippocampal and cortical slices from rats submitted to these diets was assessed. Ketone body oxidation increased while lactate oxidation decreased in hippocampal and cortical slices in both control and diabetic rats fed a HAGE diet. In parallel, the expression of both MCT1 and MCT2 increased only in the cerebral cortex in diabetic rats fed a HAGE diet. These results suggest a shift in the preferential cerebral energy substrate utilization in favor of ketone bodies in animals fed a HAGE diet, an effect that, in DM animals, is accompanied by the enhanced expression of the related transporters.