Unveiling the role of exercise in modulating plasma heat shock protein 27 levels: insights for exercise immunology and cardiovascular health.

Cardiovascular disease is one of the leading causes of mortality worldwide, primarily driven by atherosclerosis, a chronic inflammatory condition contributing significantly to fatalities. Various biological determinants affecting cardiovascular health across different age and sex groups have been identified. In this context, recent attention has focused on the potential therapeutic and preventive role of increasing circulating levels of heat shock protein 27 (plasma HSP27) in combating atherosclerosis. Plasma HSP27 is recognized for its protective function in inflammatory atherogenesis, offering promising avenues for intervention and management strategies against this prevalent cardiovascular ailment. Exercise has emerged as a pivotal strategy in preventing and managing cardiovascular disease, with literature indicating an increase in plasma HSP27 levels post-exercise. However, there is limited understanding of the impact of exercise on the release of HSP27 into circulation. Clarifying these aspects is crucial for understanding the role of exercise in modulating plasma HSP27 levels and its potential implications for cardiovascular health across diverse populations. Therefore, this review aims to establish a more comprehensive understanding of the relationship between plasma HSP27 and exercise.

Intramuscular adipose tissue, muscle area, and power as predictors of performance in breast cancer survivors.

PURPOSE: The decline in physical performance, assessed by physical tests such as the timed up and go (TUG) test, is a consequence of reduced physiological reserves at higher levels of a hierarchical process. This occurs due to changes in muscle architecture, including atrophy and fat infiltration into the muscles, which in turn lead to changes in muscle function, resulting in reduced muscle strength and power and, consequently, affecting physical performance. This study investigated predictive factors for physical performance in breast cancer survivor (BCS), focusing on intramuscular adipose tissue (IMAT), quadríceps muscle area (QMA), and muscular power. METHODS: This observational, analytical, and cross-sectional study included 23 women without a history of cancer (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m2) and 56 BCS (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m2). QMA and IMAT were assessed using computed tomography images. Muscular power and physical performance were measured using the 5-repetition sit-to-stand and TUG tests, respectively. RESULTS: IMAT (r = 0.4, P < 0.01) and muscular power (r = - 0.4, P < 0.01) were associated with TUG performance in BCS, whereas QMA (r = - 0.22, P = 0.10) showed no significant association. QMA (r = 0.55, P < 0.01) was associated with muscular power, while no significant association was found between IMAT and muscular power (r = - 0.05, P = 0.73). Age explained 19% (P < 0.01) of TUG performance variability. Adding muscular power increased explanatory power by 12% (P < 0.01), and including IMAT further increased it by 7% (P = 0.02) for TUG performance. Collectively, age, muscular power, and IMAT accounted for 38% of the performance variance in the TUG test (age, B = 0.06, P = 0.043; muscular power, B = - 0.01, P = 0.002; IMAT, B = - 0.05, P = 0.020). CONCLUSIONS: Our findings suggest that IMAT and muscular power predict the physical performance of BCS, while QMA does not have the same predictive capability.

Acute alcohol ingestion decreases the work done above the end-test power during a 3-min all-out cycling exercise.

INTRODUCTION: Alcohol ingestion influences metabolism during a subsequent exercise session, as evidenced by increased blood lactate concentration during fixed-intensity exercise. Therefore, augmented blood concentrations of alcohol may interfere with the anaerobic metabolism during high-intensity, short-duration exercise bout, thereby leading to impaired athletic performance. OBJECTIVE: This study investigated whether the acute ingestion of alcohol as ethanol modulates performance parameters derived from the power-duration relationship in a 3-min all-out cycling test that allows for identifying the power output related to heavy and severe exercise intensities. METHODS: Twenty-four recreationally active cyclists (16 men and 8 women) ingested a beverage containing either 0.4 g ethanol.kg-1 body mass (EtOH) or a placebo (PLA) solution. Thirty minutes following ingestion, they completed a 3-min all-out test to measure power output and determine the end-test power (EP) and the work done above EP (WEP). RESULTS: Alcohol ingestion decreased WEP by 16% (EtOH: 5.6 ± 2.5 kJ vs. PLA: 6.7 ± 2.4 kJ; P = .003) but did not change EP (EtOH: 211 ± 44 W vs. PLA: 212 ± 44 W; P = .671). The alcohol-mediated effect in WEP was not influenced when controlling for participants' sex or accuracy in identifying the beverage ingested. CONCLUSION: Our data indicate that alcohol ingestion impaired the anaerobic work capacity, as evidenced by the reduction in WEP during the 3-min all-out test. Moreover, the ability to exercise at an intensity above the heavy domain may be decreased after ingestion of a moderate alcohol dose.

Postmenopausal women treated for breast cancer with insulin resistance: clinical, analytical, cross-sectional.

This study aims to investigate the potential association between serum levels of cytokines, HSP60, HSP70 and IR (HOMA-IR) in postmenopausal women. We conducted a cross-sectional study involving 381 postmenopausal women, including 94 with a breast cancer diagnosis and 278 without. We analyzed anthropometric and laboratory measurements. Immunoassays were used to measure cytokines (TNF-α, IL-10, and IL-6) as well as heat shock proteins (HSP) 60 and 70 in the serum using the ELISA technique. Women diagnosed with breast cancer showed higher levels of HOMA-IR, IL-6, TNF, and HSP60, and lower levels of IL-10 and HSP70 compared to women without cancer. An association was found between HSP70 and HOMA-IR only in women with breast cancer (ß = 0.22, p = .030; without cancer: ß = 0.04, p = .404), regardless of age, waist circumference, smoking, and physical activity. No associations were observed between cytokines, HSP60, and HOMA-IR in both groups of women. HSP70 is positively associated with IR in women diagnosed with breast cancer.

Resistance Training-Induced Gains in Muscle Strength and Power Mediate the Improvement in Walking Speed in Middle-Aged Women Who Are Breast Cancer Survivors.

ABSTRACT: Santagnello, SB, Martins, FM, de Oliveira Junior, GN, de Sousa, JdeFR, Nomelini, RS, Murta, EFC, and Orsatti, FL. Resistance training-induced gains in muscle strength and power mediate the improvement in walking speed in middle-aged women who are breast cancer survivors. J Strength Cond Res 38(4): 773-782, 2024-(a) Ascertain whether lower muscle mass, strength (1 repetition maximum [1RM]), and power (Pmax) in middle-aged women who are breast cancer survivors (BCS), when compared with women of a similar age never diagnosed with cancer (WNC), are related with lower walking speed (WS). (b) Ascertain whether changes in WS are associated with changes in muscle mass, 1RM, and (or) Pmax after resistance training (RT) in middle-aged BCS. A cross-section study was performed. Twenty WNC and 21 BCS were evaluated for lean mass of legs (LLM), 1RM (knee extension), muscle quality index (MQI = 1RM/LLM), Pmax (maximum muscle power-knee extension), and fast WS (10 and 400-meters). Randomized clinical trial was performed. The BCS were randomly divided into the control group ( n = 9) and the RT group ( n = 11). Breast cancer survivors exhibited lower 1RM (24.2%, p ˂ 0.001), Pmax (30.6%, p ˂ 0.001), MQI (22.2%, p = 0.001), and WS (10-m = 17.0%, p ˂ 0.001 and 400-m = 10.5%, p = 0.002) than WNC. Resistance training increased 1RM (31.6%, p = 0.001), MP (29.0%, p = 0.012), MQI (28.5%, p = 0.008), and WS (10-m = 9.4%, p = 0.009 and 400-m = 6.2%, p = 0.006) in BCS. The changes in WS were positively associated with 1RM (10-m = 68%, p = 0.001 and 400-m = 37%, p = 0.036) and Pmax (10-m = 56%, p = 0.005 and 400-m = 40%, p = 0.027) and MQI (10-m = 63%, p = 0.043 and 400-m = 37%, p = 0.035). Resistance training-induced gains in muscle strength and power mediate the improvement in WS in middle-aged BCS. Resistance training is an effective strategy to improve WS in middle-aged BCS.

Lower-Body Resistance Training Reduces Interleukin-1ß and Transforming Growth Factor-ß1 Levels and Fatigue and Increases Physical Performance in Breast Cancer Survivors.

ABSTRACT: Martins, FM, Santagnello, SB, de Oliveira Junior, GN, de Sousa, JdFR, Michelin, MA, Nomelini, RS, Murta, EFC, and Orsatti, FL. Lower-body resistance training reduces interleukin-1ß and transforming growth factor-ß1 levels and fatigue and increases physical performance in breast cancer survivors. J Strength Cond Res 37(2): 439-451, 2023-This article ascertains whether resistance training (RT) improves inflammatory markers, fatigue (sensations and fatigability), and physical performance in breast cancer survivors (BCS) and investigates whether the changes in the inflammatory markers, fatigue, and physical performance are associated with each other. Volunteers were randomly divided into 2 groups: control group (n = 11) and RT group (n = 11). Resistance training (3 sets of 8-12 repetitions with 80% 1 repetition maximum (1RM) on 4 exercises-leg extension, leg curl, 45° leg press, and calf raise) was performed 3 times a week for 12 weeks. Self-reported fatigue (SRF), fatigability (critical torque [CT] and W prime [W']), muscle strength, and circulating inflammatory markers were assessed using the Brief Fatigue Inventory, iDXA, 1RM test, protocol of 60 maximal voluntary isometric contractions, and enzyme-linked immunosorbent assay, respectively. Resistance training reduced interleukin (IL)-1ß, transforming growth factor (TGF)-ß1, and SRF score and increased muscle strength, 6-minute walk test (6MWT), CT, and W'. In the RT group, the changes in SRF were positively associated with the changes in IL-1ß. The changes in muscle strength were associated with the changes in CT and W', and the changes in the 6MWT were associated with the changes in CT, W', muscle strength, and SRF. Resistance training improved fatigue and physical performance and reduced IL-1ß, and TGF-ß1 in BCS. Although improvement in fatigability seems to be dependent on the increase in muscle strength, improvement in the sensation of fatigue seems to be dependent on the reduction in IL-1ß after RT. Increase in physical performance seems to be dependent on improvement in muscle strength and fatigue.

Interleukin-15 are associated with insulin resistance in postmenopausal women with metabolic syndrome.

OBJECTIVE: To determine if higher levels of circulating interleukin (IL)-15 are positively associated with improvement in insulin resistance in postmenopausal women (PW) with metabolic syndrome (MS). METHODS: According to the median value of IL-15 at baseline, PW older than or equal to 45 years were divided into two groups: higher (n = 43) and lower (n = 42) IL-15. There was a 9-month follow-up period with clinical assessments at baseline and at 9 months (criteria of metabolic syndrome, body fat, and insulin resistance). Insulin resistance (IR) was calculated according to the Homeostasis Model Assessment-estimated insulin resistance (HOMA-IR). For IL-1ß, IL-6, IL-10, IL-13, IL-33, IL-15, and TNF-α was determined using immunoassay Magnetic Bead Panel. RESULTS: There was an interaction between the time and group only for insulin (p = .008) and HOMA-IR (p = .024). After adjusting for confounding variables (clinical and ILs), the HOMA-IR (p = .006) and insulin (p = .003) were lower in the higher-IL-15 group [HOMA-IR: 2.2 (95% CI: 1.9-2.5) and insulin: 9.1 µIU/mL (95% CI: 7.9-10.3)] when compared to the lower-IL-15 group [HOMA-IR: 3.1 (95% CI: 2.6-3.6) and insulin: 12.9 (95% CI: 11.1-14.9)] after 9 months of follow-up. CONCLUSION: Higher levels of circulating IL-15 are positively associated with improvements in IR in PW with MS.

Higher levels of circulating interleukin (IL)-15 are positively associated with improvement in insulin resistance (IR) in postmenopausal women (PW) with metabolic syndrome (MS).This relationship is independent of levels of other cytokines (IL-1ß, IL-6, IL-10, IL-13, IL-33, and TNF-α).The levels of circulating IL-15 may be used as a prognostic biomarker for IR in PW with MS.The study opens the door for future studies on IL-15's role in treating IR among PW with MS.

Resistance Training Volume Enhances Muscle Hypertrophy, but Not Strength in Postmenopausal Women: A Randomized Controlled Trial.

ABSTRACT: Nascimento de Oliveira Júnior, G, de Freitas Rodrigues de Sousa, J, Augusto da Silva Carneiro, M, Martins, FM, Santagnello, SB, Campos Souza, MV, and Orsatti, FL. Resistance training volume enhances muscle hypertrophy, but not strength in postmenopausal women: a randomized controlled trial. J Strength Cond Res 36(5): 1216-1221, 2022-Among several possible resistance training (RT) variables to be manipulated, the training volume has been considered as a critical variable to maximize RT-induced hypertrophy. Many of the studies that compared one set of RT with 3 sets have failed to show a difference in muscle hypertrophy in older adults. However, it is not clear whether further increases in RT volume (i.e., 6 sets) would result in even greater RT-related hypertrophy than 3 sets in older adults. This study aimed to investigate whether higher-volume RT (HV-RT) maximizes gains in lean body mass and muscle strength (MS) when compared with lower-volume RT (LV-RT) in postmenopausal women (PW). Fifty-eight PW were randomized into 1 of the 3 groups: control group (CT, no exercise), HV-RT (6 sets per exercise), and LV-RT (3 sets per exercise). Volunteers took part in a supervised training program (leg press 45°, leg extension, leg curl and standing calf raises) and were assessed for leg lean mass (LLM; dual X-ray absorptiometry) and lower limb MS (leg press and leg extension; 1 repetition maximum [1RM]) before and after 12 weeks of RT. Both HV-RT and LV-RT groups increased (p < 0.05) LLM and MS when compared with the CT group. Higher increases in LLM gains were observed for the HV-RT group when compared with the LV-RT group (6.1 and 2.3%, p < 0.001). Both HV-RT and LV-RT groups similarly increased 1RM in the leg press and leg extension. Thus, there seems to be a dose-response relationship between RT volume and muscle hypertrophy, but not for MS gains in PW.

Improvements in muscle strength, power, and size and self-reported fatigue as mediators of the effect of resistance exercise on physical performance breast cancer survivor women: a randomized controlled trial.

PURPOSE: To gain more knowledge about the mechanism (i.e., mediators) of resistance exercise (RE)-induced improvements in physical performance (PP), we seek to investigate whether improvements in muscle strength (MS), muscle power (MP), and lean body mass (LBM) and (or) self-reported fatigue (SRF) are mediators of the effect of RE on PP in breast cancer survivor women (BCSW). METHODS: The volunteers were randomly divided into two groups: control group (CT; n = 9) and resistance exercise (RE; n = 11). The RE protocol consisted of three sets in each exercise (leg extension, leg curl, 45° leg press, and calf raise), between 8 and 12 repetitions per set, with an estimated load of 80% of one-repetition maximum (1RM), and three times a week on non-consecutive days for 12 weeks. The CT group performed only stretching exercises twice a week. SRF, maximal muscle power (Pmax), MP, LBM, and PP were assessed using the Brief Fatigue Inventory Questionnaire; 1RM test; isoinertial dynamometer; DXA; and walking speed, sit-to-stand (STS), and timed up and go (TUG) test, respectively. RESULTS: Following 12 weeks, the RE group reduced SRF and increased MP, Pmax, LBM, and performance in all tests (walking speed, STS, and TUG) when compared with the CT group. There were significant associations of the changes in LBM, MS, Pmax, and SRF with changes in physical performance tests only in the RE group. CONCLUSION: Our findings suggest that improvements in LBM, MS, MP, and self-reported fatigue mediate the effect of resistance exercise on physical performance in BCSW.

Lower-Load is More Effective Than Higher-Load Resistance Training in Increasing Muscle Mass in Young Women.

Franco, CMdC, Carneiro, MAdS, Alves, LTH, Júnior, GNdO, de Sousa, JdFR, and Orsatti, FL. Lower-load is more effective than higher-load resistance training in increasing muscle mass in young women. J Strength Cond Res 33(7S): S152-S158, 2019-This study was designed to investigate the impact of load (higher vs. lower) performed until or close to volitional fatigue on muscle strength (MS) and fat and bone-free lean mass (FBFM) in young women. To do this, 32 women performed resistance training (RT) in 1 of 2 conditions: lower-load RT (LL; n = 14, age = 24.3 ± 4.8 years and body mass index [BMI] = 23.3 ± 2.8 kg·m) and higher-load RT (HL; n = 18, age = 23.0 ± 3.3 years and BMI = 22.4 ± 3.3 kg·m). Leg FBFM (DXA) and MS (1 repetition maximum-unilateral leg extension [LE]) were evaluated before and after 9 weeks (the first week was used for familiarization) of RT. Both groups performed 3 unilateral exercises (LE, leg curl, and leg press), 3 sets per exercise, 60-90 seconds of rest between sets, 2 days per week. In the LL group, the loads used in the exercises were the loads necessary to perform 30-35 repetitions in the first set. For the HL group, the loads used were the loads necessary to perform 8-10 repetitions in the first set. The LL group showed higher RT volume than the HL. Both groups showed leg muscle mass gains (p < 0.05). However, the LL group was better [p = 0.032 and effect size (eta = 0.14 [large]) than the HL group in leg FBFM gains (LL = 0.3 kg [IC 95%: 0.4 kg; 0.2 kg] and HL = 0.1 kg [IC 95%: 0.2 kg; 0.0 kg]). Both groups showed MS gains, without any difference between them (LL = 3.4 kg [IC 95%: 4.4 kg; 2.5 kg] and HL = 4.2 kg [IC 95%: 5.1 kg; 3.3 kg]; p = 0.239). Thus, lower-load RT is more effective than higher-load RT in increasing FBFM, but not MS in novice young women.

Acute resistance exercise reduces increased gene expression in muscle atrophy of ovariectomised arthritic rats.

OBJECTIVE: We studied the effect of resistance exercise (RE) on mRNA levels of atrogin-1, MuRF-1, and myostatin in the gastrocnemius muscle of arthritic rats after loss of ovarian function (LOF). MATERIAL AND METHODS: Thirty female Wistar rats (nine weeks old, 195.3 ±17.4 grams) were randomly allocated into five groups: control group (CT-Sham; n = 6); group with rheumatoid arthritis (RA; n = 6); group with rheumatoid arthritis subjected to RE (RAEX; n = 6); ovariectomy group with rheumatoid arthritis (RAOV; n = 6); and an ovariectomy group with rheumatoid arthritis subjected to RE (RAOVEX; n = 6). After 15 days of intra-articular injections with Met-BSA the animals were subjected to RE and six hours after workout were euthanised. RESULTS: The rheumatoid arthritis provoked reduction in the cross-sectional area (CSA) of muscle fibres, but the CSA was lower in the RAOV when compared to the RA groups. Skeletal muscle atrogin-1 mRNA level was increased in arthritic rats (RA and RAOV), but the atrogin-1 level was higher in RAOV group when compared to other arthritic groups. The Muscle MuRF-1 mRNA level was also increased in the RAOV group. The increased atrogin-1 and MuRF-1 mRNA levels were lower in the RAOVEX group than in the RAOV group. The myostatin mRNA level was similar in all groups, except for the RAOVEX group, in which it was lower than the other groups. CONCLUSIONS: LOF results in increased loss of skeletal muscle-related ubiquitin ligases (atrogin-1 and MuRF-1). However, the RE reduces the atrogin-1, MuRF-1, and myostatin mRNA levels in muscle of arthritic rats affected by LOF.

Low-load resistance training promotes muscular adaptation regardless of vascular occlusion, load, or volume.

PURPOSE: This study investigates the impact of two different intensities and different volumes of low-load resistance training (LLRT) with and without blood flow restriction on the adaptation of muscle strength and size. METHODS: The sample was divided into five groups: one set of 20 % of one repetition maximum (1RM), three sets of 20 % of 1RM, one set of 50 % of 1RM, three sets of 50 % of 1RM, or control. LLRT was performed with (OC) or without (NOC) vascular occlusion, which was selected randomly for each subject. The maximal muscle strength (leg extension; 1RM) and the cross-sectional area (quadriceps; CSA) were assessed at baseline and after 8 weeks of LLRT. RESULTS: 1RM performance was increased in both groups after 8 weeks of training: OC (1 × 50 % = 20.6 %; 3 × 50 % = 20.9 %; 1 × 20 % = 26.6 %; 3 × 20 % = 21.6 %) and NOC (1 × 50 % = 18.6 %; 3 × 50 % = 26.8 %; 1 × 20 % = 18.5 %; 3 × 20 % = 21.6 %; 3 × 20 % = 24.7 %) compared with the control group (-1.7 %). Additionally, the CSA was increased in both groups: OC (1 × 50 % = 2.4 %; 3 × 50 % = 3.8 %; 1 × 20 % = 4.6 %; 3 × 20 % = 4.8 %) and NOC (1 × 50 % = 2.4 %; 3 × 50 % = 1.5 %; 1 × 20 % = 4.3 %; 3 × 20 % = 3.8 %) compared with the control group (-0.7 %). There were no significant differences between the OC and NOC groups. CONCLUSION: We conclude that 8 weeks of LLRT until failure in novice young lifters, regardless of occlusion, load or volume, produces similar magnitudes of muscular hypertrophy and strength.

Influence of sex on cytokines, heat shock protein and oxidative stress markers in response to an acute total body resistance exercise protocol.

BACKGROUND/OBJECTIVE: This study evaluated the influence of sex on changes in cytokines, heat shock proteins (HSPs), and oxidative stress in response to a single bout of total body resistance exercise. METHODS: Sixteen healthy volunteers (8 men and 8 women), active and recreationally trained in resistance exercise, were subjected to a single bout of total body resistance exercise (3 × 8-10 repetition maximum, 10 exercises, rests periods of 90-120 seconds). Serum creatine kinase (CK), interleukin (IL)-6, IL-10, tumor necrosis factor-α, HSP60, HSP70, thiobarbituric acid reactive substance, and reduced glutathione were assessed at pre-protocol, and 1 hour, 4 hours, and 24 hours post-protocol. RESULTS: Both men and women had a similar increase in CK (p < 0.05) activity at 24 hours post-exercise. Significant sex differences were observed for IL-6. In the men, an increase from baseline was noted at 1 hour for IL-6. In women, an increase from baseline was noted at 4 hours only for IL-6. There was a significant correlation between peak IL-6 blood level and CK level at 24 hours only in the women. No significant changes were observed in IL-10, tumor necrosis factor-α, HSP60, HSP70, thiobarbituric acid reactive substance, and reduced glutathione. CONCLUSION: Acute total body resistance exercise altered circulating levels of IL-6 and sex differences existed in the temporal pattern and magnitude of this response.

Propulsive forces and muscle activation during gait: comparisons between premenopausal and postmenopausal midlife women.

OBJECTIVE: The aim of this study was to investigate whether there is a reduction in propulsive force during gait in postmenopausal women compared with premenopausal women. METHODS: Forty-four women (21 premenopausal and 23 postmenopausal women) aged 40 to 55 years were selected. The ability to reach peak propulsive forces was assessed during the step execution test. The test was performed at the usual speed on 2 nonconsecutive days, with two attempts per day, using a force platform. Four temporal parameters were defined and calculated: initiation phase, preparation phase, swing phase, and total time. Peak force (anteroposterior and vertical) and time to reach peak force were obtained in both preparation and swing phases. The rate of force development was defined as peak force divided by time to reach peak force. RESULTS: The postmenopausal women group presented a longer time in the preparation phase (540.6 ± 77 ms vs 482.5 ± 93 ms, P = 0.024) and consequently a longer total time in the step execution test (1,191 ± 106.4 ms vs 1,129 ± 114.3 ms, P = 0.045). There were differences between the groups for the rate of force development in the anteroposterior (postmenopausal women, 142.5 ± 38.1 N/s vs premenopausal women, 174.7 ± 70.5 N/s; P = 0.022) and vertical directions in the preparation phase (postmenopausal women, 102.7 ± 62.3 N/s vs premenopausal women, 145.3 ± 71 N/s; P = 0.012). No significant differences ( P > 0.05) were found in force, time to peak force, and rate of force development during the swing phase. In addition, there were no observed differences in surface electromyography of the medial and lateral gastrocnemius muscles during the preparation phase and swing phase of the step execution test between the two groups. CONCLUSIONS: Postmenopausal women exhibited lower ability to generate propulsive force rapidly (rates of force development) in both the anteroposterior and vertical directions during the preparation phase of gait compared with premenopausal women. This indicates that postmenopausal women experience a reduction in propulsive force during gait.

Retinol-binding protein 4 is a potential biomarker of changes in lean mass in postmenopausal women.

Identifying biomarkers can help in the early detection of muscle loss and drive the development of new therapies. Research suggests a potential link between retinol-binding protein 4 (RBP4) and muscle mass, particularly in postmenopausal women. This study aimed to examine the association between baseline RBP4 levels and changes in appendicular lean mass (ALM), an indicator of muscle mass, in postmenopausal women. A 12-month follow-up period (n = 153) included baseline and 12-month ALM assessments using DXA. ALM was normalized to squared height (ALMI). Baseline evaluations encompassed insulin resistance via HOMA-IR and immunoassay magnetic bead panel measurements of RPB4, IL-6, TNF-α, and IL-10. Postmenopausal women were categorized into higher (n = 77) and lower (n = 76) RPB4 groups based on baseline RPB4 values. Their changes in ALMI were compared using Mann-Whitney tests. General linear model was employed to evaluate the predictive power of baseline RBP4 for ALMI changes, adjusting for confounding variables: age, physical activity, smoking status, body fat, HOMA-IR, inflammatory markers (TNF-α and IL-6), and anti-inflammatory factor (IL-10). The higher RBP4 group exhibited a more pronounced reduction in ALMI compared to the lower RBP4 group (Higher RBP4 = -0.39 kg/m2, 95% CI: -0.48 to -0.31 kg/m2vs. Lower RBP4 = -0.24 kg/m2, 95% CI: -0.32 to -0.15 kg/m2, P = 0.011). After adjusting for confounding factors, the association between baseline RBP4 changes and ALMI remained (b = -0.008, SE = 0.002, P < 0.001), indicating higher baseline RBP4 values linked to greater ALMI reduction. Our findings support RBP4 as a potential biomarker for changes in muscle mass in postmenopausal women.

Impact of vitamin D supplementation on modulating heat-shock proteins in postmenopausal women: a randomized, double-blind, placebo-controlled study.

OBJECTIVE: The aim of this study was to examine the effect of vitamin D (VitD) supplementation on serum heat-shock proteins (HSP) in postmenopausal women (PW). METHODS: In this double-blind, placebo-controlled trial, 160 PW aged 45 to 65 years with amenorrhea 12 months or more were randomized into two groups: 80 PW in VitD group (oral supplementation with 1,000 IU VitD 3 /d) or 80 PW in placebo group. The PW were assessed at baseline and after 10 months of intervention. Plasma concentrations of 25-hydroxyVitD (25[OH]D) were measured by high-performance liquid chromatography. HSP27/pS78/pS82, HSP27/total, HSP60, HSP70/72, and HSP90α levels were assessed in serum using a multiplexed bead immunoassay. RESULTS: HSP27 (pS78/pS82 [ P < 0.035] and total [ P < 0.001]) levels increased in the supplemented group when compared with the control group. There was no effect of VitD supplementation on HSP60, HSP70/72, and HSP90α levels. CONCLUSIONS: Vitamin D supplementation increases serum HSP27 level in PW.

Heterogeneity in resistance training-induced muscle strength responses is associated with training frequency and insulin resistance in postmenopausal women.

BACKGROUND: In older adults, muscle strength (MS), a key component of sarcopenia, is essential to maintaining independence and physical capacity. The rate of MS decline typically accelerates during the menopausal transition. Although MS has been shown to increase with resistance training (RT), the response to training is quite heterogeneous. Thus, if contributing factors to RT non-responsiveness to MS gains are identified, it may be possible to develop more effective and personalized ways to improve MS or identify individuals who may benefit from RT interventions. This study assessed potential factors that may contribute to MS response heterogeneity in postmenopausal women: training frequency, serum FSH and estrogen levels, adiposity, inflammation marker, and insulin resistance. METHODS: One hundred and thirteen individuals participated in a 16-week program of supervised RT (3 sets, 8-12 repetitions, and 2-3 times/week). A control group (CTL, n = 63 - no performed the RT) was used as the comparator arm. Body composition (skinfold) and blood samples (metabolic and inflammatory indicators and hormones) were measured at baseline. Knee extensor strength (1RM) was measured at baseline, 8 weeks, and 16 weeks. RESULTS: Only the RT group increased 1RM after 8 weeks (RT = 14 ± 12% vs. CTL = 6 ± 15%). Both groups increased 1RM after 16 weeks, with the RT group showing a greater increase than the CTL group (RT = 31 ± 23% vs CTL = 13 ± 25%). After 8 weeks of RT, 41 (36% of total) individuals were considered non-responders (based on control group responses) and 27 (24% of total) individuals after 16 weeks. At week 8, lower RT frequency (2 times/week vs. 3 times/week) was associated with higher odds of being non-responder (3 times, P = 0.048). At week 16, lower RT frequency (13 times, P = 0.009) and higher HOMA-IR (for every unit increase, odds increase by 40%, P = 0.022) were associated with higher odds of being non-responder. Higher QUICKI was associated with lower odds of being non-responder (for every unit increase, odds decrease by 16%, P = 0.039). Moreover, higher RT frequency (17 times, P = 0.028) and higher QUICKI (for every unit increase, odds increase by 41%, P = 0.017) were associated with higher odds of becoming a responder at week 16, being a non-responder at week 8. CONCLUSION: Heterogeneity in RT-induced MS responses is associated with training frequency and insulin resistance in postmenopausal women.

Resistance training-induced improvement in exercise tolerance is not dependent on muscle mass gain in post-menopausal women.

Menopause transition may impair muscle function, decreasing exercise tolerance. The torque-duration relationship (hyperbolic curve) forms a practical framework within which exercise tolerance may be explored. In this regard, resistance training (RT) increases the curvature constant of this relationship (W'). Muscle hypertrophy and strength gains have been suggested as possible mediators of RT-induced improvement in W', however, it is unclear what the main mediator is. Higher-volume RT (HV-RT), beyond that recommended by RT-guidelines (i.e. three sets per exercise), may promote greater hypertrophy, but not higher strength gains. Hence, this study aimed to investigate whether greater hypertrophy in HV-RT maximises W' gain when compared to LVRT in postmenopausal women (PW). Fifty-eight PW were randomised to the control group (CTRL), HV-RT (six sets per exercise) or LV-RT (three sets per exercise). They underwent a 12-week RT program and were assessed for W', thigh lean body mass (TLBM) and maximal isometric voluntary contraction (MIVC). The TLBM gain was higher (P < 0.001) in the HV-RT (9.4%) than LV-RT (3.7%). However, both HV-RT and LV-RT similarly increased MIVC (9.7% vs. 16.5%, P = 0.063) and W' (26.4% vs. 34.6% P = 0.163). Additionally, the changes in W' were associated with the changes in TLBM (31%, P = 0.003) and MIVC (52%, P= <0.001). However, when the changes in TLBM and MIVC were inserted into the predictive model, only the MIVC (33%, P = 0.002) was a predictor of W'. Thus, although HV-RT promoted greater hypertrophy than LV-RT, HV-RT does not seem to maximise W' in PW.

Different cutoff points to diagnose low muscle mass and prediction of osteoporosis in postmenopausal women.

OBJECTIVE: This study aimed to verify which of the different cutoff points of low muscle mass (LMM) based on appendicular lean mass (ALM) is associated with osteoporosis in postmenopausal women (PMW). METHODS: Cross-sectional study. PMW (n = 355) were classified for the presence of osteoporosis (score <-2.5 standard deviations) at the femoral neck and lumbar spine and LMM (three cutoff points: ALM < 15 kg; ALM/height2 [ALM index] <5.67 kg/m2 and ratio between ALM and body mass index [ALMBMI] <0.512). RESULTS: After adjustments for confounding factors, binary logistic regression showed that ALM and ALM index were associated with osteoporosis at the lumbar spine (odds ratio [OR] = 5.3 [95% CI: 2.3-12.5] and OR = 2.5 [95% CI: 1.0-6.2], respectively) and only ALM was associated with osteoporosis at the femoral neck (OR = 16.1 [95% CI: 4.1-62.5]). When women were classified as having osteoporosis in at least one site, only ALM was associated with osteoporosis (OR = 7.7 [95% CI: 3.3-15.6]). There was no association between ALMBMI and osteoporosis. The predictive value of ALM for osteoporosis decreased after BMI or height were included as a covariate in the model. CONCLUSION: Absolute ALM (<15 kg) seems to be the most suitable for predicting osteoporosis based on LMM in PMW.

Association between anthropometric indicators of body fat and metabolic risk markers in post-menopausal women.

OBJECTIVE: to evaluate anthropometric indicators of body fat and their association with metabolic risk markers in postmenopausal women. METHODS: A cross-sectional study with 80 Brazilian women (40-70 years) was carried out. Body mass index (BMI = weight/height(2)), waist circumference (WC) and waist-to-hip ratio (WHR) were obtained for anthropometric evaluation. Trunk fat mass (TFM) was measured by dual-energy X-ray absorptiometry. The following metabolic variables were evaluated: total cholesterol (TC), HDL, LDL, triglycerides (TG), as well as glycemia and insulin to determine insulin resistance (HOMA-IR). RESULTS: Overweight and obesity were observed in 81% of the women. Values of WC >88 cm were observed in 68.5% of the women. On average, TC, LDL and TG levels were above normal levels in 60, 50 and 42.5% of the women, respectively; and HDL was normal in 82.5%. IR was observed in 37.5% of the women. Positive correlations were found between anthropometric indicators and TFM (P < 0.05). WC was most correlated with TFM (r = 0.92), followed by BMI (r = 0.88) and by WHR (r = 0.48; P < 0.05). All anthropometric indicators and TFM showed significant negative correlations with HDL and significant positive correlations with HOMA-IR (P < 0.05). Only WHR was significantly associated with dysglycemia (R(2) = 12%), hypertriglyceridemia (R(2) = 17%) and decreased HDL (R(2) = 27%). WC was significantly associated with HOMA-IR (R(2) = 34%). CONCLUSION: WC and WHR are anthropometric measures that showed strong correlation with TFM and with metabolic risk markers in postmenopausal women.