Effect of three different exercise trainings on functional capacity in early stage severe burn patients: A randomized controlled trial.

BACKGROUND: This study investigated the effects of three different exercise protocols on functional capacity in early-stage burn patients. METHODS: A total of 25 patients hospitalized in the Burn Center (wards and intensive care unit) were included in the study. The individuals were divided into three groups by covariate adaptive randomization according to burn percentage and type: 1 - standard treatment, 2 - standard treatment + aerobic exercise training, 3 - standard treatment + combined exercise (aerobic and resistance) determined by metabolic status. Individuals were evaluated weekly for six weeks from the first day of hospitalization using the 6-minute walk test, physiological cost index, and Medical Research Council muscle-strength measurements to assess functional capacity. A portable metabolism tracker device measured the metabolic status of all patients. RESULTS: Aerobic exercises and combined exercise (aerobic and resistance), when added to standard treatment and determined by metabolic status, were more effective in enhancing functional capacity than standard treatment alone (p<0.05). Patients performing the combined exercise (aerobic and resistance) showed faster improvement in functional capacity determined according to metabolic status than those in the other two groups (p<0.05). CONCLUSION: Aerobic exercises, when added to standard treatment and combined with aerobic and resistance exercises based on metabolic status, are more effective at improving functional capacity than standard treatment alone. Further controlled studies are required to explore the potential long-term benefits of this approach.

Online-delivered resistance exercise intervention among racially diverse breast cancer survivors: Feasibility, acceptability, and exploratory outcomes of B-REP.

PURPOSE: The aims are to determine the feasibility of an online-delivered resistance exercise program among racially diverse breast cancer survivors and to conduct an exploratory analysis of the intervention on muscular strength, physical activity levels, health-related quality of life, and self-efficacy. METHODS: A 2-arm randomized controlled trial study design with assessments at pre- and post-intervention was used. Participants (n = 52) were recruited from clinics at the host institution and randomized to either intervention (n = 28) or minimal contact control (MCC) conditions (n = 24). All participants received a 12-week individualized resistance exercise prescription based on their baseline functional strength assessment. Intervention participants exercised one-on-one once per week over Zoom with an exercise trainer. MCC participants received no supervision. Descriptive statistics were used to determine feasibility and acceptability (primary outcomes). Repeated measures ANOVAs were used to examine exploratory outcomes. RESULTS: The intervention demonstrated high rates for feasibility outcomes of enrollment (80.0%) and post-intervention assessment completion (92.9%). Acceptability outcomes were high for session attendance (98.0%) and satisfaction (Mscore = 4.87 out of 5, SD = .18). The intervention group increased upper- (p < .01) and lower- (p < .02) body strength compared to MCC condition. CONCLUSIONS: The intervention was feasible, acceptable, and demonstrated increases in muscular strength. Limitations include a small sample recruited from one cancer center. Future research is needed to determine longitudinal impacts of resistance exercise on survivorship outcomes. Online-delivered resistance exercise shows promising efficacy among racially diverse breast cancer survivors. CLINICALTRIALS: gov registration: NCT04562233 on September 18, 2020.

The effect of low-intensity suspension training with blood flow restriction on GH, IGF-1, and their association with physical fitness in young women.

Blood flow restriction (BFR) has been incorporated in resistance training for over 20 years. We aimed to investigate the impact of low-intensity suspension training with BFR (LIST+BFR) on GH, IGF-1, and their association with physical fitness in young women. Thirty-six active women participated and were randomly assigned to either the high-intensity suspension training (HIST), LIST+BFR, or control (CON) groups. Training groups exercised three sessions weekly for 8 weeks. The CON only engaged in regular physical activity. Fasting serum hormones and physical fitness were assessed 48 h before and after the training intervention. GH and IGF-1 levels significantly higher in the LIST+BFR compared to the HIST and CON. These hormones were significantly higher by HIST, compared to CON. LIST+BFR led to significant enhancements in muscular strength and endurance compared to HIST and CON. Additionally, HIST significantly higher than compared to CON. Sprinting and agility time lower in both suspension training groups rather than the CON. No significant between-groups differences were found in weight. There was a large or moderate correlation between GH and IGF-1 and muscular strength, endurance, sprint, and agility performance. LIST+BFR could more enhanced GH, IGF-1, and muscular strength and endurance in females than HIST.

The impact of exercise on growth factors in postmenopausal women: a systematic review and meta-analysis.

BACKGROUND: Aging results in many changes in health status, body composition, muscle strength, and, ultimately, functional capacity. These changes coincide with significant alterations in the endocrine system, such as insulin-like growth factor-1 (IGF-1) and IGF-binding proteins (IGFBPs), and may be associated with many symptoms of aging. The objectives of this study is to investigate the potential influence of different types of exercise, such as resistance training and aerobic training, on IGF-1 and IGFBP-3 levels in postmenopausal women. METHODS: Medline, Scopus, and Google Scholar databases were systematically searched up to November 2023. The Cochrane Collaboration tool was used to assess the risk of bias and the quality of the studies. The random-effects model, weighted mean difference (WMD), and 95% confidence interval (CI) were used to estimate the overall effect. Between-study heterogeneity was assessed using the chi-squared and I2 tests. RESULTS: Seventeen studies were included in the present systematic review and 16 studies were included in the meta-analysis. The pooled results from 16 studies (21 trials) with 1170 participants examining the impact of exercise on IGF-1 concentration showed a significant increase in IGF-1, and the pooled results among six studies (trials) showed a significant decrease in IGFBP-3 concentration (730 participants). In addition, resistance training and aerobic training had a significant effect on increasing IGF-1 concentration post-exercise compared with placebo. CONCLUSION: Based on this meta-analysis, Women who have completed menopause and followed an exercise routine showed changes in IGF-1 and IGFBP-3 levels that can indirectly be associated with risk of chronic age-related conditions.

Muscle activity and hypoalgesia in blood flow restricted versus unrestricted effort-matched resistance exercise in healthy adults.

This study assessed muscle activity (root mean square, RMS, and median frequency, MDF) to evaluate the acute response to blood flow restriction (BFR) resistance exercise (RE) and conventional moderate intensity (MI) RE. We also performed exploratory analyses of differences based on sex and exercise-induced hypoalgesia (EIH). Fourteen asymptomatic individuals performed four sets of unilateral leg press with their dominant leg to volitional fatigue under two exercise conditions: BFR RE and MI RE. Dominant side rectus femoris (RF) and vastus lateralis (VL) muscle activity were measured using surface electromyography (sEMG) through exercise. RMS and MDF were calculated and compared between conditions and timepoints using a linear mixed model. Pressure pain thresholds (PPT) were tested before and immediately after exercise and used to quantify EIH. Participants were then divided into EIH responders and nonresponders, and the differences on RMS and MDF were compared between the two groups using Hedges' g. RMS significantly increased over time (RF: p = 0.0039; VL: p = 0.001) but not between conditions (RF: p = 0.4; VL: p = 0.67). MDF decreased over time (RF: p = 0.042; VL: p < 0.001) but not between conditions (RF: p = 0.74; VL: p = 0.77). Consistently lower muscle activation was found in females compared with males (BRF, RF: g = 0.63; VL, g = 0.5. MI, RF: g = 0.72; VL: g = 1.56), with more heterogeneous findings in MDF changes. For BFR, EIH responders showed greater RMS changes (Δ RMS) (RF: g = 0.90; VL: g = 1.21) but similar MDF changes (Δ MDF) (RF: g = 0.45; VL: g = 0.28) compared to nonresponders. For MI, EIH responders demonstrated greater increase on Δ RMS (g = 0.61) and decrease on Δ MDF (g = 0.68) in RF but similar changes in VL (Δ RMS: g = 0.40; Δ MDF: g = 0.39). These results indicate that when exercising to fatigue, no statistically significant difference was observed between BFR RE and conventional MI RE in Δ RMS and Δ MDF. Lower muscle activity was noticed in females. While exercising to volitional fatigue, muscle activity may contribute to EIH.

Aerobic high-intensity interval training and maximal strength training in patients with unspecific musculoskeletal disorders improve V̇O2peak and maximal strength more than moderate training.

Improving peak oxygen uptake (V̇O2peak) and maximal strength are key objectives of rehabilitation for patients with unspecific musculoskeletal disorders (MSDs). Although high-intensity training yield superior outcomes for these factors, patients with MSDs may not tolerate high-intensity due to pain and fear. Therefore, we examined the effect and feasibility of incorporating aerobic high-intensity intervals (HIITs) and maximal strength training (MST) in a standard clinical rehabilitation program for patients with unspecific MSDs. 73 patients (45 ± 10 years) with MSDs partaking in a standard, public, and 4-week rehabilitation program were randomized to high-intensity training (HG: 4 × 4 minutes intervals at ∼90% of maximal heart rate; HRmax, and 4 × 4 repetitions leg press at ∼90% of 1 repetition maximum; 1RM, with maximal intended velocity) or keep todays treatment of low-to moderate-intensity training (MG: various cycling, walking, and/or running activities at ∼70%-80% of HRmax and 3 × 8 - 10 repetitions leg press at ∼75% of 1RM without maximal intended velocity). HG improved V̇O2peak (12 ± 7%) and leg press 1RM (43 ± 34%) more than moderate-intensity group (V̇O2peak; 5 ± 6%, 1RM; 19 ± 18%, both p < 0.001). We observed that no adverse events and no between-group differences in dropout rate or self-reported quality of life (both p > 0.05). There were positive correlations between improved V̇O2peak and improved physical (p = 0.024) and emotional (0.016) role functioning. We conclude that both high-intensity interval training and MST are feasible and improve V̇O2peak and maximal strength more than standard low-to moderate-intensity treatment of patients with unspecific MSDs. Our findings suggest that high-intensity training should be implemented as a part of standard clinical care of this patient population.

Using Resistance-Band Tests to Evaluate Trunk Muscle Strength in Chronic Low Back Pain: A Test-Retest Reliability Study.

Exercise is a front-line intervention to increase functional capacity and reduce pain and disability in people with low strength levels or disorders. However, there is a lack of validated field-based tests to check the initial status and, more importantly, to control the process and make tailored adjustments in load, intensity, and recovery. We aimed to determine the test-retest reliability of a submaximal, resistance-band test to evaluate the strength of the trunk stability muscles using a portable force sensor in middle-aged adults (48 ± 13 years) with medically diagnosed chronic low back pain and healthy peers (n = 35). Participants completed two submaximal progressive tests of two resistance-band exercises (unilateral row and Pallof press), consisting of 5 s maintained contraction, progressively increasing the load. The test stopped when deviation from the initial position by compensation movements occurred. Trunk muscle strength (CORE muscles) was monitored in real time using a portable force sensor (strain gauge). Results revealed that both tests were highly reliable (intra-class correlation [ICC] > 0.901) and presented low errors and coefficients of variation (CV) in both groups. In particular, people with low back pain had errors of 14-19 N (CV = 9-12%) in the unilateral row test and 13-19 N (CV = 8-12%) in the Pallof press. No discomfort or pain was reported during or after the tests. These two easy-to-use and technology-based tests result in a reliable and objective screening tool to evaluate the strength and trunk stability in middle-aged adults with chronic low back pain, considering an error of measurement < 20 N. This contribution may have an impact on improving the individualization and control of rehabilitation or physical training in people with lumbar injuries or disorders.

Impacts of Wearable Resistance Placement on Running Efficiency Assessed by Wearable Sensors: A Pilot Study.

Wearable resistance training is widely applied to enhance running performance, but how different placements of wearable resistance across various body parts influence running efficiency remains unclear. This study aimed to explore the impacts of wearable resistance placement on running efficiency by comparing five running conditions: no load, and an additional 10% load of individual body mass on the trunk, forearms, lower legs, and a combination of these areas. Running efficiency was assessed through biomechanical (spatiotemporal, kinematic, and kinetic) variables using acceleration-based wearable sensors placed on the shoes of 15 recreational male runners (20.3 ± 1.23 years) during treadmill running in a randomized order. The main findings indicate distinct effects of different load distributions on specific spatiotemporal variables (contact time, flight time, and flight ratio, p ≤ 0.001) and kinematic variables (footstrike type, p < 0.001). Specifically, adding loads to the lower legs produces effects similar to running with no load: shorter contact time, longer flight time, and a higher flight ratio compared to other load conditions. Moreover, lower leg loads result in a forefoot strike, unlike the midfoot strike seen in other conditions. These findings suggest that lower leg loads enhance running efficiency more than loads on other parts of the body.

Effect of warm-up protocols using lower and higher loads on multiple-set back squat volume-load.

Background: The present study aimed to investigate the effects of post-activation performance enhancement (PAPE) after three warm-up protocols on back squat performance in trained men. Methods: Fourteen resistance-trained men performed conditioning activity (CA) with high-load (HL-CA), low-load (LL-CA), or usual specific warm-up as a control (CON). HL-CA consisted of one set of three repetitions with 90% of one repetition maximum (RM); LL-CA consisted of one set of six repetitions with 45% of 1 RM performed at maximal velocity; CON involved eight repetitions with 45% of 1 RM at controlled velocity. The participant's performance was measured using the total number of repetitions and volume load (reps × load × sets). Results: There were no significant differences between warm-up for the total number of repetitions (p = 0.17) or total volume load (p = 0.15). There was no difference between conditions for the number of repetitions (main condition effect; p = 0.17); however, participants achieved a significantly higher volume load after HL-PAPE than after CON for the first set (p = 0.04). Conclusion: High or low equated-load CA used as warm-up strategies did not potentiate subsequent performance enhancement in multiple-set back squat exercise performed until muscle failure in comparison with usual warm-up.

Effects of five types of exercise on vascular function in postmenopausal women: a network meta-analysis and systematic review of 32 randomized controlled trials.

Background: As women age, especially after menopause, cardiovascular disease (CVD) prevalence rises, posing a significant global health concern. Regular exercise can mitigate CVD risks by improving blood pressure and lipid levels in postmenopausal women. Yet, the optimal exercise modality for enhancing vascular structure and function in this demographic remains uncertain. This study aims to compare five exercise forms to discern the most effective interventions for reducing cardiovascular risk in postmenopausal women. Methods: The study searched PubMed, Web of Science, Cochrane, EBSCO, and Embase databases. It conducted a network meta-analysis (NMA) of randomized controlled trials (RCTs) on five exercise interventions: continuous endurance training (CET), interval training (INT), resistance training (RT), aerobic combined with resistance training (CT), and hybrid-type training (HYB). Outcome measures included carotid artery intima-media thickness (IMT), nitric oxide (NO), augmentation index (AIx), pulse wave velocity (PWV), and flow-mediated dilatation (FMD) of the brachial artery. Eligible studies were assessed for bias using the Cochrane tool. A frequentist random-effects NMA was employed to rank exercise effects, calculating standardized mean differences (SMDs) with 95% confidence intervals (CIs). Results: The analysis of 32 studies (n = 1,427) indicates significant increases in FMD with CET, INT, RT, and HYB in postmenopausal women. Reductions in PWV were significant with CET, INT, RT, CT, and HYB. AIx decreased significantly with INT and HYB. CET, INT, and CT significantly increased NO levels. However, no significant reduction in IMT was observed. SUCRA probabilities show INT as most effective for increasing FMD, CT for reducing PWV, INT for decreasing AIx, CT for lowering IMT, and INT for increasing NO in postmenopausal women. Conclusion: The study demonstrates that CET, INT, RT, and HYB have a significant positive impact on FMD in postmenopausal women. Furthermore, all five forms of exercise significantly enhance PWV in this population. INT and HYB were found to have a significant positive effect on AIx in postmenopausal women, while CET, INT, and CT were found to significantly improve NO levels. For improving vascular function in postmenopausal women, it is recommended to prioritize INT and CT exercise modalities. On the other hand, as CET and RT were not ranked at the top of the Sucra value ranking in this study and were less effective than INT and CT as exercise interventions to improve vascular function in postmenopausal women, it is not recommended that CET and RT be considered the preferred exercise modality.

The effects of five weeks of climbing training, on and off the wall, on climbing specific strength, performance, and training experience in female climbers-A randomized controlled trial.

Recent research has elucidated the effects of strength training on climbing performance. Although local muscular endurance training of the upper-limbs and finger flexors is frequently suggested, there is currently insufficient evidence to support its impact on climbing performance and climbing-specific strength. Furthermore, there is no evidence on climbers' experiences related to training and the likelihood of consistent engagement. In addition, the effects of more climbing-specific strength training on walls with built in lights and adjustable angles have yet to be examined. The low percentage of studies involving female subjects, additionally, demonstrates a significant gap in understanding the specific effects of strength training on women in the context of climbing. The aim of this study was thus to assess the effects of five-week on-, and off-the-wall climbing training on climbing performance, climbing-specific strength, and training experience. Thirty-one female lower-grade to advanced climbers were randomly assigned to either a control group, an off-the-wall training or an on-the-wall training group. Apart from the training regimen, all groups followed their usual climbing and bouldering routine. Subjects trained at least twice a week. Bouldering performance, and maximum strength and muscular endurance of the finger flexors and upper-limbs were assessed before and after the intervention. Furthermore, rate of perceived exertion and discomfort, exercise enjoyment, and exercise pleasure were assessed during the first and last training session, as well as after two and a half weeks of training. Intrinsic training motivation was assessed after the last training session. The results showed trends towards positive effects of off-the-wall training on climbing-specific strength, and on-the-wall training on climbing technique. Furthermore, our finding revealed high exercise enjoyment and intrinsic training motivation for both on- and off-the-wall training. Hence, lower-grade to advanced female climbers should rely on personal training preferences.

Regulation of exercise on heart rate variability in perimenopausal and postmenopausal women. / 运动对围绝经期和绝经后妇女心率变异性的调节.

Heart rate variability (HRV) is a non-invasive quantitative measure of cardiac autonomic nervous activity. Due to the increase of age and the decrease of estrogen level in perimenopausal and postmenopausal women, the cardiac autonomic nervous function is abnormal, increasing the risk of cardiovascular disease. Proper exercise can increase estrogen levels, improve cardiovascular health, regulate cardiac autonomic nervous activity, and reduce the risk of cardiovascular disease. Low-moderate intensity aerobic exercise, resistance exercise, aerobic combined resistance exercise and mind-body exercise have positive effects on HRV in perimenopausal and postmenopausal women. Therefore, summarizing the effects of different exercise modes on HRV in perimenopausal and postmenopausal women, as well as the mechanism of exercise training improvement on HRV, so as to adopt better exercise strategies to improve HRV of perimenopausal and postmenopausal women, and thus reduce the risk of cardiovascular diseases and improve the health level and quality of life of perimenopausal and postmenopausal women.

Levels of circulating angiotensin-converting enzyme 2 are affected by acute exercise and correlate with markers of physical fitness in male athletes.

While under physiological conditions angiotensin-converting enzyme 2 (ACE2) is an antagonist of vasoconstrictive agents in the renin-angiotensin-aldosterone system (RAAS), in the context of SARS coronavirus 2 (SARS-CoV-2) ACE2 serves as the gateway into cells. Furthermore, RAAS has previously been shown to be influenced by exercise training and is suggested to be involved in skeletal muscle mass maintenance. Given this connection, the investigation of circulating ACE2 plasma protein concentration before and following acute and chronic endurance and resistance exercise could increase the understanding of the implications of the exposure of athletes to SARS-CoV-2. Therefore, this study investigated levels of circulating ACE2 in lifelong high-level trained endurance and resistance athletes and control subjects in response to either acute endurance or resistance exercise. Results show no baseline differences in absolute ACE2 concentration between groups, but a strong negative correlation with levels of fitness and positive correlation with BMI in control subjects. Furthermore, acute endurance exercise significantly increased ACE2 levels across all groups, but only in the strength group in response to resistance exercise. This indicates that circulating ACE2 plasma levels are influenced by levels of fitness and health, and that acute endurance exercise has a stronger effect on plasma ACE2 levels than resistance exercise.

Differential training benefits and motor unit remodeling in wrist force precision tasks following high and low load blood flow restriction exercises under volume-matched conditions.

BACKGROUND: Blood flow restriction (BFR) resistance training has demonstrated efficacy in promoting strength gains beneficial for rehabilitation. Yet, the distinct functional advantages of BFR strength training using high-load and low-load protocols remain unclear. This study explored the behavioral and neurophysiological mechanisms that explain the differing effects after volume-matched high-load and low-load BFR training. METHODS: Twenty-eight healthy participants were randomly assigned to the high-load blood flow restriction (BFR-HL, n = 14) and low-load blood flow restriction (BFR-LL, n = 14) groups. They underwent 3 weeks of BFR training for isometric wrist extension at intensities of 25% or 75% of maximal voluntary contraction (MVC) with matched training volume. Pre- and post-tests included MVC and trapezoidal force-tracking tests (0-75%-0% MVC) with multi-channel surface electromyography (EMG) from the extensor digitorum. RESULTS: The BFR-HL group exhibited a greater strength gain than that of the BFR-LL group after training (BFR_HL: 26.96 ± 16.33% vs. BFR_LL: 11.16 ± 15.34%)(p = 0.020). However, only the BFR-LL group showed improvement in force steadiness for tracking performance in the post-test (p = 0.004), indicated by a smaller normalized change in force fluctuations compared to the BFR-HL group (p = 0.048). After training, the BFR-HL group activated motor units (MUs) with higher recruitment thresholds (p < 0.001) and longer inter-spike intervals (p = 0.002), contrary to the BFR-LL group, who activated MUs with lower recruitment thresholds (p < 0.001) and shorter inter-spike intervals (p < 0.001) during force-tracking. The discharge variability (p < 0.003) and common drive index (p < 0.002) of MUs were consistently reduced with training for the two groups. CONCLUSIONS: BFR-HL training led to greater strength gains, while BFR-LL training better improved force precision control due to activation of MUs with lower recruitment thresholds and higher discharge rates.

Effects of acupuncture combined with trunk strengthening training on balance and gait abilities in stroke hemiplegic patients.

This study aimed to observe the effects of acupuncture combined with trunk strengthening training on balance and gait abilities in stroke hemiplegic patients. Sixty stroke hemiplegic patients were selected and randomly divided into a treatment group and a control group, with 30 patients in each group. The control group received conventional rehabilitation training and trunk strengthening exercises, while the treatment group received acupuncture in addition to the same interventions. Before and after 8 weeks of treatment, patients were assessed using the Holden Functional Ambulation Categories and Berg Balance Scale, and measurements were taken for step length, step width, and gait speed. Prior to treatment, there were no significant differences in Holden scores, Berg scores, step length, step width, or gait speed between the 2 groups (P > .05). After 8 weeks of treatment, significant improvements were observed in the aforementioned parameters in both groups (P < .05), with the acupuncture group showing significantly greater improvement compared to the control group (P < .05). Acupuncture combined with trunk strengthening training can significantly improve balance and gait impairments in stroke hemiplegic patients.

Slow-velocity eccentric-only resistance training improves symptoms of type 2 diabetic mellitus patients by regulating plasma MMP-2 and -9.

OBJECTIVE: This study investigated the intervention effect of slow-velocity eccentric-only resistance training on type 2 diabetic mellitus (T2DM) patients based on the role of matrix metalloproteinase-2 and -9 (MMP-2 and -9) in regulating extracellular matrix homeostasis. METHODS: 50 T2DM patients were randomly divided into the slow-velocity eccentric-only resistance training group (E) and control group (C). The E group performed eccentric-only resistance training 3 times a week, every other day for 10 weeks, while the C group did not. Blood samples were collected before and after training, and subjects were tested for changes in clinical parameters, insulin resistance indices [fasting insulin, homeostatic model assessment insulin resistance (HOMA-IR)], MMP-2 and -9, and hydroxyproline, and muscle strength (12-RM), respectively. RESULTS: After 10 weeks of training, the E group showed significant decreases in fasting glucose (P < .05), insulin (P < .05), insulin resistance indices (P < .05), hemoglobin A1c (HbA1c) (P < .01), triglycerides (P = .06) and MMP-2 (P < .05), while total cholesterol (P < .05), MMP-9 (P < .05), hydroxyproline (P < .01), Creatine Kinase (CK) (P < .05), and muscle strength (P < .001) significantly increased. There were no significant changes in the count of neutrophil, lymphocyte and platelet, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), high-density lipoprotein cholesterol (HDL-c), and low-density lipoprotein cholesterol (LDL-c). Compared with the C group, the E group showed a trend of a significant decrease in triglyceride (P < .05), lymphocyte count (P < .05), fasting glucose (P = .07), and plasma MMP-2 (P < .05), while MMP-9 (P < .05), hydroxyproline (P < .001), and muscle strength (P < .01) significantly increased. However, no significant changes were observed in insulin and insulin resistance indices, HbA1c, total cholesterol, HDL-c, LDL-c, CK, and other inflammatory indicators. CONCLUSIONS: Slow-velocity eccentric-only resistance training was beneficial for T2DM, but the potential role of MMP-2 and -9 in regulating extracellular matrix homeostasis is very different in T2DM patients.

Effects of Exercise Type on Muscle Strength and Body Composition in Men and Women: A Systematic Review and Meta-Analysis.

Background and Objectives: There are typical differences in body composition and distribution of muscle fiber types between women and men. However, research investigating the effects of exercise based on sex differences is limited, and studies examining sex differences in physiological adaptations according to exercise type are scarce. We aimed to compare the effects of exercise types on muscle strength and body composition in men and women through a meta-analysis. Materials and Methods: A systematic literature search was conducted using the PubMed/Medline, Web of Science, CINAHL, and EBSCO databases. Keywords included "endurance training", "resistance training", "concurrent training", "muscle strength", "body composition", "sex characteristics", and "men and women". The standardized mean difference (SMD) was presented separately for men and women based on the pre- and post-intervention values for each exercise type. Results: Concurrent training showed the greatest effect on the increase in leg press muscle strength in men, and resistance training showed the greatest effect in women. Concurrent training showed the greatest effect size in both men and women in increasing bench press muscle strength. Resistance training and concurrent training showed a small effect size on lean mass reduction in both men and women. Endurance training and concurrent training significantly reduced fat mass in men. However, no significant changes in fat mass were observed in any exercise type among women. Conclusions: Concurrent training is the most efficient type of exercise for men, as it is effective in increasing upper- and lower-body muscle strength, increasing lean mass, and reducing fat mass. Resistance training is most effective in increasing muscle strength in females, whereas endurance training is most effective in reducing fat mass. However, it is difficult to corroborate these results because of the lack of study samples included in the analysis and the differences in exercise methods, participant age, and exercise duration.

Effects of heavy-load strength training during (neo-)adjuvant chemotherapy on muscle strength, muscle fiber size, myonuclei, and satellite cells in women with breast cancer.

To investigate the effects of heavy-load strength training during (neo-)adjuvant chemotherapy in women with breast cancer on muscle strength, body composition, muscle fiber size, satellite cells, and myonuclei. Women with stage I-III breast cancer were randomly assigned to a strength training group (ST, n = 23) performing supervised heavy-load strength training twice a week during chemotherapy, or a usual care control group (CON, n = 17). Muscle strength and body composition were measured and biopsies from m. vastus lateralis collected before the first cycle of chemotherapy (T0) and after chemotherapy and training (T1). Muscle strength increased significantly more in ST than in CON in chest-press (ST: +10 ± 8%, p < .001, CON: -3 ± 5%, p = .023) and leg-press (ST: +11 ± 8%, p < .001, CON: +3 ± 6%, p = .137). Both groups reduced fat-free mass (ST: -4.9 ± 4.0%, p < .001, CON: -5.2 ± 4.9%, p = .004), and increased fat mass (ST: +15.3 ± 16.5%, p < .001, CON: +16.3 ± 19.8%, p = .015) with no significant differences between groups. No significant changes from T0 to T1 and no significant differences between groups were observed in muscle fiber size. For myonuclei per fiber a non-statistically significant increase in CON and a non-statistically significant decrease in ST in type I fibers tended (p = .053) to be different between groups. Satellite cells tended to decrease in ST (type I: -14 ± 36%, p = .097, type II: -9 ± 55%, p = .084), with no changes in CON and no differences between groups. Strength training during chemotherapy improved muscle strength but did not significantly affect body composition, muscle fiber size, numbers of satellite cells, and myonuclei compared to usual care.

Postural control during the back squat at different load intensities in powerlifters and weightlifters.

BACKGROUND: The movement of the barbell has been detected as success factor for the snatch and the clean and jerk events. As the barbell's movement has been shown to be related to the athlete's body movement, we hypothesized that the latter could be a success factor also for the back squat (BS) event. Hence, this study aimed to investigate postural control during the execution of the BS at different load intensities in powerlifters and weightlifters. METHODS: Seventeen powerlifters and weightlifters were enrolled and the one-repetition maximum (1-RM) of the BS of each participant was measured. Afterwards, the assessment of postural control during the execution of the BS at different load intensities (i.e. 60%, 70%, 80%, 90%, 100%) of the 1-RM of each participant was carried out through a posturographic platform to measure the displacement of the centre of pressure (CoP). The following parameters were considered: sway path length (SPL), sway ellipse surface (SES), length/surface (LFS ratio), sway mean speed (SMS), CoP coordinates along X and Y planes. RESULTS: We found a significant increase in SPL and LFS ratio, and a significant decrease in SMS as the load intensity increased. In detail, we detected a significant difference in: (a) SPL between the BS at 60% and 80%, 60% and 90%, 60% and 100%; between the BS at 70% and 90%, 70% and 100%; between the BS at 80% and 100%; and between the BS at 90% and 100%; (b) SMS between the BS at 60% and 80%, 60% and 90%; (c) LFS ratio between the BS at 60% and 90%, 60% and 100%. CONCLUSIONS: These results suggest that powerlifters and weightlifters adopt different postural control strategies depending on the load intensity when performing the BS. Our findings showed that higher effort could affect postural control during the BS. Thus, postural control could be considered a success factor for the BS.

Caffeine Abstinence in Habituated Users: Cardiovascular Responses to Exercise With Blood Flow Restriction.

CONTEXT: Blood flow restriction resistance exercise studies often require caffeine abstinence to avoid cardiovascular effects that could change the blood flow restriction stimulus. However, effects may be attenuated for habituated users. OBJECTIVE: To compare cardiovascular responses to blood flow restriction resistance exercise when habituated users consume or abstain from caffeine. DESIGN: Thirty participants completed a 3-visit within-subject study beginning with familiarization and caffeine intake questionnaire. METHODS: Visits 2 and 3 consisted of blood flow restriction resistance exercise (3 sets bicep curls to failure, 30% 1-repetition max, 40% arterial occlusion pressure [AOP]), following participants' normal caffeine consumption (CAFF) or abstaining (ABS). AOP, systolic (SBP) and diastolic (DBP) blood pressure, and heart rate were measured preexercise and postexercise. Prevalues and preexercise to postexercise change scores for SBP, DBP, AOP (all millimeters of mercury), heart rate (in beats per minute), and repetitions were compared between conditions. Results are represented as mean (SD). RESULTS: Preexercise AOP was similar for CAFF (137.8 [14.4]) and ABS (137.1 [14.9], BF10 = 0.2), although pre-SBP was higher for CAFF (115.4 [9.8]) than ABS (112.3 [9.4], BF10 = 1.9). Pre-DBP was similar between conditions. The exercise-induced change in AOP was greater for CAFF (18.4 [11.2]) than ABS (13.2 [14.9]), though evidence was anecdotal (BF10 = 0.7). Exercise-induced changes in SBP, DBP, and heart rate were similar between conditions (all BF10 ≤ 0.40). More repetitions were completed for CAFF (63 [26]) than ABS (57 [17], BF10 = 2.1). CONCLUSIONS: The findings of this study suggest that for habituated users, maintaining daily caffeine habits will not have substantial effects on common cardiovascular variables relevant to blood flow restriction.