Effects of Progressive and Velocity-Based Autoregulatory Resistance Training on Lower-Limb Movement Ability in Taekwondo Athletes.

BACKGROUND: Both autoregulatory progressive resistance exercise (APRE) and velocity-based resistance training (VBRT) utilize real-time monitoring of athlete physical performance to adjust training loads to provide appropriate training stimuli. However, the monitoring and adjustment approaches differ between both methods. This study aimed to compare the effects of APRE and VBRT on the muscle strength, power, and agility of college taekwondo athletes. HYPOTHESIS: Eight weeks of APRE and VBRT will promote similar results to strength gains in regards maximal strength, but VBRT will be superior to APRE in explosive power and agility. STUDY DESIGN: Clinical trial. LEVEL OF EVIDENCE: Level 3. METHODS: Thirty taekwondo athletes were divided randomly into 2 groups (VBRT/APRE), and all participants completed an 8-week APRE/VBRT intervention. Maximum strength, explosive power, and agility performance were assessed during the squat 1-repetition maximum (1RM), countermovement jump (CMJ), drop jump (DJ), kicking strength test (KST), taekwondo-specific agility test (TSAT), and hexagon test (HT). RESULTS: Highly significant time effects (P < 0.01) were observed for squat 1RM, CMJ, and TSAT in both the APRE and VBRT groups. However, there were no significant group-by-time differences for any of the measured outcomes to intergroup (P > 0.05), but APRE had a small effect size (ES) over VBRT for CMJ (ES = 0.48, η2p = 0.06), TSAT (ES = 0.26, η2p = 0.02), and HT (ES = 0.42, η2p = 0.05). CONCLUSION: An 8-week autoregulatory APRE and VBRT can both effectively improve both the maximal strength, explosive power, and agility performance of taekwondo athletes, with APRE exhibiting potential advantages in improving CMJ, TSAT, and HT. CLINICAL RELEVANCE: These results provide important insights into the selection of suitable resistance training programs by professional coaches, taking into account athlete needs, training efficiency, and safety considerations.

Case report: A creatine kinase-borg scale values-based approach to tailor physical training in a central core myopathy patient.

Background: Patients with central core myopathy (CCM) can be at risk of exercise-induced rhabdomyolysis and myalgia. Despite its possible positive effects, physical training has been long avoided in these patients as no population-specific exercise adaption strategies have been developed. Here we present the case of a 17-year-old male CCM patient who underwent a 3-month training program tailored to a preliminary test aimed at assessing his physical exertion tolerance measured via changes in serum creatine kinase (CK). Methods: The preliminary tolerance test consisted of three 25-minute sessions (one session per week) of physical exercise (aerobic, resistance and mixed) at an intensity quantified as level 6 of the Borg Category Ratio (CR) 0-10 scale. A blood sample to assess CK was conducted 36 h following eachsession. The intervention consisted of a training program (three sessions per week) including both resistance and aerobic exercises concomitant with a personalized nutritional plan. Before and after intervention, a battery of metabolic (indirect calorimetry, bioimpedance) and cardiopulmonary (CPET) tests were performed. Results: After training, improvements of the anaerobic threshold (+6.9%), normalized VO2 max (+15%) and body composition (muscle mass, +1.1 kg; fat mass, -1.1 kg were observed without pain, rhabdomyolysis, and blood CK augmentation compared to pretraining values. Conclusion: Our results highlight that a mixed aerobic/resistance training, properly tailored and supported by a specific nutritional plan, may safely improve the physical fitness and body composition in a CCM patient. Dosing exercise-induced CK serum change following Borg CR-10 intensity assessment, may be useful to correctly tailor physical exercise in these patients.

Sex-related differences in the load-velocity and load-power relationships of the decline bench press exercise.

The purpose of this study was to analyse the load-velocity and load-power relationships of the decline bench press exercise (DBPE) and to compare sex-related differences. Twelve young healthy men and women performed a progressive loading test for the determination of 1RM strength and individual load-velocity and load-power relationship in the DBPE. A very close relationship between mean propulsive velocity (MPV) and %1RM was observed (R2 = 0.94). This relationship improved when plotting data separately by sex (R2 = 0.96-97). Individual load-velocity profiles gave an R2 = 0.99 ± 0.01. The relationship between mean propulsive power (MPP) and %1RM was R2 = 0.23. When separating data by sex, R2 = 0.64-73 were obtained. Individual load-power profiles gave an R2 of 0.93 ± 0.07. Significant sex-related differences were found for MPV, with males having faster velocities than females from 30% to 40% 1RM (p = 0.01) and for MPP, with males having greater MPP (W) than females from 30% to 95% 1RM (p < 0.001). The results of this study show that a strong correlation exists between relative load and MPV/MPP in the DBPE, allowing the possibility of using one to predict the other with great precision, especially when a sex-specific equation is used.

Effect of a new resistance training method on the metaboreflex in cardiac rehabilitation patients: a randomized controlled trial.

Patients with cardiac disease exhibit exaggerated sympathoexcitation, pressor, and ventilatory responses to muscle metaboreflex activation (MMA). However, the effects of cardiac rehabilitation (CR) and especially resistance training (RT) modalities on MMA are not well known. This study investigated how CR impacts MMA in such patients, specifically examining the effects of two different resistance training (RT) protocols following 12 weeks of CR. In addition to endurance exercises, 32 patients were randomized into either a 3/7 RT modality (comprising 5 sets of 3-7 repetitions) or a control (CTRL) modality (involving 3 sets of 9 repetitions), with distinct inter-set rest intervals (15 s for 3/7 and 60 s for CTRL). MMA, gauged by blood pressure (BP) and ventilatory (Ve) responses during a handgrip exercise at 40% effort and subsequent post-exercise circulatory occlusion, demonstrated CR's significant impact. Systolic BP, initially at + 28 ± 23% pre-CR, improved to + 11 ± 15% post-CR (P = .011 time effect; P = .131 group effect). Diastolic BP showed a similar trend, from + 27 ± 23% to + 13 ± 15% (P = .099 time effect; P = .087 group effect). Ve, initially at + 60 ± 39%, reduced to + 14 ± 19% post-CR (P < .001 time effect; P = .142 group effect). Critical parameters-maximal oxygen consumption, lean mass, hand grip, and quadriceps strength-exhibited parallel increases in both 3/7 and CTRL groups (P < .05 time effect; P > .3 group effect). Ultimately, CR demonstrated comparable improvements in MMA across both RT modalities, indicating its positive influence on cardiovascular responses and physical performance in individuals with cardiac conditions.

Effectiveness of Resistance Training Program on Body Composition in Adults Following Vegan Diet versus Omnivorous Diet; Developed in Mobile Health Modality.

BACKGROUND: The vegan diet (VEGD) has gained popularity in recent years for ecological and ethical reasons, as well as for its health benefits. In addition to the type of diet, the resistance training program (RTP) plays a fundamental role as one of the main natural anabolic stimuli to increase musculoskeletal mass and reduce fat mass. METHODS: The study was a 16-week non-randomized controlled clinical trial consisting of three RTP sessions per week. The sample included 70 Chilean individuals, aged between 18 and 59 years, who had been following a VEGD or omnivorous diet (OMND) for the past 6 months. Four groups were established: Vegan Diet Resistance Training Program (VEGD-RTP), Vegan Diet Control (VEGD-C), Omnivorous Diet Resistance Training Program (OMND-RTP), and Omnivorous Diet Control (OMND-C). RESULTS: The sample consisted of 47 women and 23 men, with a mean age of 30.1 (±8.6) years. A reduction of 1.20% in the percentage of fat mass (%FM) was observed in the VEGD-RTP group (r = 0.554, p = 0.016), as well as a reduction of 0.70 kg in kilograms of fat mass (KFM) (r = 0.480, p = 0.036). The OMND-RTP group decreased %FM by 0.90% (r = 0.210, p = 0.432) and KFM by 0.50 kg (r = 0.109, p = 0.683). CONCLUSIONS: RTP combined with VEGD or OMND significantly reduced the percentage of fat mass, although its effect was more significant in the VEGD-RTP participants.

Nutritional Management and Physical Activity in the Treatment of Sarcopenic Obesity: A Review of the Literature.

BACKGROUND: The prevalence of sarcopenic obesity among adults aged ≥65 years is increasing worldwide. It is a condition that describes the concomitant presence of sarcopenia and obesity, but it appears to be associated with greater increases in the risks for disability, morbidity, and mortality than the two conditions combined. The current review aims to summarize the available literature data on the effectiveness of lifestyle modification for the management of this high-risk geriatric syndrome. METHODS: We conducted a comprehensive search across multiple databases, including PubMed, Scopus, Web of Science, and Cochrane Library, for publications published from January 1950 to June 2024. RESULTS: The detection of early preventive and therapeutic approaches to combat sarcopenic obesity is essential for healthy aging. There is ample evidence that suggests that poor dietary habits and physical inactivity are the main reasons for the development of sarcopenic obesity and should thus be the main targets for intervention. In the absence of effective pharmacological interventions, the best effect on sarcopenic obesity is achieved by combination with proper dietary intervention and regular physical activity according to the individual's health condition. CONCLUSIONS: Further research is needed to discover the most effective strategy for the prevention and treatment of sarcopenic obesity, as well as potential pharmacological options to improve muscle mass and function in older populations with physical restrictions.

Hybrid Training System Consisting of Synchronized Neuromuscular Electrical Stimulation for Voluntary Exercise Using an Articular Motion Sensor.

Neuromuscular electrical stimulation (NMES) is widely used for improving muscle strength, preventing muscle atrophy, and decreasing pain. Recently, NMES has become a substitute for exercise therapy for metabolism improvement and functional capacity improvement. However, NMES has several disadvantages. First, slow-twitch muscle contractions are insufficient because the recruitment pattern of NMES does not obey Henneman's size principle. Second, when using surface electrodes, it is difficult to contract deep skeletal muscles at the application site. Third, electrical stimulation causes discomfort. Therefore, we devised a simultaneous combination of NMES and voluntary muscle contractions to overcome the weak points of NMES. A hybrid training system (HTS) that resists the motion of a volitionally contracting agonist muscle with force generated by its electrically stimulated antagonist was developed as a technique to combine the application of NMES and volitional contractions. This motion sensor makes it possible to simultaneously combine voluntary movements with NMES. Our HTS synchronizes with voluntary movements, enhancing safety and reducing discomfort. This HTS enhances the exercise effect of even simple exercise. So far, our HTS has been reported to be effective for muscle strength enhancement, prevention of muscle atrophy, improvement of physical function, pain relief, enhancement of physical fitness, and improvement of metabolic function. HTS are expected to be useful methods in environments where sufficient exercise load is not available or for individuals with low exercise tolerance.

Sex-Specific Variations in Glycated Hemoglobin Responses to Structured Exercise in Type 2 Diabetes: Healthcare Implications of Walking and Strength Training on Glycemic Control.

Type 2 diabetes mellitus (T2DM) affects one in ten individuals in the United States, with rates expected to rise significantly. This novel study aimed to evaluate the impact of a structured exercise program on glycated hemoglobin (HbA1c) levels among males and females with T2DM, and to compare the effects of different volumes of combined aerobic and resistance exercise. A total of 67 adult participants with T2DM were randomly assigned to two groups: Group 1 (exercise classes and walking sessions) and Group 2 (exercise classes only). After 10 weeks, 39 participants completed the intervention and 34 had complete HbA1c records. Results indicated a significant improvement in HbA1c levels overall, with males exhibiting a greater decrease compared to females. Minimal baseline differences were observed between the walking and non-walking groups and improvements in HbA1c were noted in both groups with no significant differences. These findings suggested potential sex-specific differences in response to structured exercise programs. The study highlighted the importance of tailored exercise interventions in healthcare while managing T2DM. Further research is necessary to optimize exercise prescriptions and evaluate long-term benefits, but the current evidence supports structured exercise as a valuable component of comprehensive diabetes care. This research underscores the need for personalized approaches in exercise regimens, contributing to the growing body of knowledge on sex-specific responses to T2DM interventions.

The methodology of resistance training is crucial for improving short-medium distance front crawl performance in competitive swimmers: a systematic review and meta-analysis.

Background: Resistance training is often a part of the routine training regimen for competitive swimmers. However, due to the variety of resistance training methodology, the results can be inconsistent and sometimes unsatisfactory. Clear recommendations are still lacking at present. Aims: 1) Quantify the impact of resistance training on swimmers' upper limb maximum strength, front crawl performance and key technical parameters; 2) Find out the key technical parameters for improving front crawl performance-stroke rate or length; 3) Through subgroup analysis determine the best methodology of resistance training to enhance the front crawl. Methods: Systematic search in the PubMed, Embase, and Web of Science databases. Meta-analyses using the inverse-variance are performed to compare swimmers' upper limb maximum strength, front crawl performance and key technical parameters in resistance training and habitual aquatic training. A subgroup analysis was performed to examine whether the results were affected by the methodology of resistance training. Results: Thirteen studies (267 competitive swimmers) met the inclusion criteria. The results of meta-analysis showed that resistance training significantly improved upper limbs maximum muscle strength, and 25, 50, 100, and 200 m front crawl performance in competitive swimmers. And improvements in swimming performance may simply resulted from resistance training increasing stroke rate rather than stroke length. In addition, the results of subgroup analysis showed that only concurrent resistance training (CRT) and power training (PT) ultimately improved swimming performance by increasing the maximum muscle strength of the upper limbs. Conclusion: Resistance training significantly enhances competitive swimmers' upper limb strength and front crawl performance across various distances. The improvement in performance is likely attributed to an increased stroke rate rather than stroke length. In addition, CRT and PT are particularly effective, indicating the importance of selecting the appropriate methodology of resistance training for optimal swimming performance enhancement. Systematic review registration: https://doi.org/10.17605/OSF.IO/3JEGW.

The Effects of Slow Breathing during Inter-Set Recovery on Power Performance in the Barbell Back Squat.

Slow breathing (SB) reduces sympathetic nervous system activity, the heart rate (HR), and blood pressure (BP) and increases parasympathetic nervous system activity, HR variability, and oxygen saturation which may lead to quicker recovery between bouts of exercise. Therefore, the purpose of this study was to examine whether a SB technique using the 4-7-8 method between sets of barbell back squats (SQs) would attenuate drops in power and bar velocity. In a randomized, crossover design, 18 healthy resistance-trained college-aged males (age: 20.7 ± 1.4 years, body height: 178.6 ± 6.4 cm, body mass: 82.2 ± 15.0 kg, 4.5 ± 2.4 years of experience) performed 5 sets of 3 repetitions of SQs with normal breathing (CON) or SB during the 3-min recovery between sets. Peak and average power and bar velocity were assessed using a linear positioning transducer. HR recovery (RHR), systolic BP recovery (RBP), the rating of perceived exertion (RPE) and the rating of perceived recovery score (RS) were assessed after each set. There were no significant differences between conditions for peak and average power and bar velocity, RBP, RPE, and RS (p > 0.211). SB led to a greater RHR after set 2 (SB: 51.0 ± 14.9 bpm vs. CON: 44.5 ± 11.5 bpm, p = 0.025) and 3 (SB: 48.3 ± 13.5 bpm vs. CON: 37.7 ± 11.7 bpm, p = 0.006) compared to the CON condition. SB was well tolerated, did not hinder nor improve training performance and improved RHR after the middle sets of SQs. Further investigations are warranted to examine the effects of other SB techniques and to determine SB's effects on different training stimuli as well as its effects over an entire workout and post-workout recovery metrics.

Identification of Peripheral Fatigue through Exercise-Induced Changes in Muscle Contractility.

The aim of this study was to assess whether tensiomyography is a tool sensitive enough to detect peripheral fatigue. Twenty-six strength-trained men were split into two groups: 1) a fatigued group (FG), who performed a full-squat (SQ) standardized warm-up plus 3 x 8 SQs with 75% 1RM with a 5-min rest interval, and 2) a non-fatigued group (NFG), who only did the SQ standardized warm-up. The countermovement jump (CMJ), maximal isometric force (MIF) in the SQ at 90º knee flexion, and TMG in vastus medialis (VM) and vastus lateralis (VL) muscles were assessed pre- and post-protocols. Data were analyzed through mixed ANOVA, logistic regression analysis, and receiver-operating curves. There were significant group x time interactions (p < 0.01) for CMJ height, MIF, maximal radial displacement (Dm), and radial displacement velocity (Vrd90) since the FG acutely decreased in these variables, while no significant changes were observed for the NFG. The logistic regression showed a significant model for detecting fatigue, whether it used the CMJ or MIF, with only the relative change in VL-Vrd90 as a fatigue predictor. The determination of the area under the curve showed that Dm and Vrd90 had good to excellent discriminative ability. Dm and Vrd90 are sensitive to detect fatigue in VL and VM muscles in resistance training contexts.

Safety and Effects of a Four-Week Preoperative Low-Load Resistance Training With Blood Flow Restriction on Pre- and Postoperative Quadriceps Strength in Patients Undergoing Total Knee Arthroplasty: A Single-Blind Randomized Controlled Trial.

Background/Objectives Enhancing preoperative quadriceps strength and mitigating quadriceps strength loss due to total knee arthroplasty (TKA) is crucial for post-TKA recovery. This study compared the safety and effect of a four-week preoperative regimen of low-load resistance training with blood flow restriction (LLRT-BFR) with those of low-intensity resistance training with slow movement and tonic force generation (LST) on the pre- and postoperative quadriceps strength in patients undergoing TKA. Methods In this randomized controlled trial, 22 patients were assigned to either the LLRT-BFR (n=11) or LST (n=11) group. Primary outcomes included changes in quadriceps strength before and after the intervention and surgery. To assess safety, we monitored D-dimer and high-sensitivity C-reactive protein levels pre- and post-intervention. Statistical analysis involved independent samples t-tests and Mann-Whitney U tests for group comparisons of quadriceps strength changes. Additionally, a two-way repeated-measures analysis of variance was used to assess safety parameters. Results No significant differences were observed between the BFR and LST groups in terms of the rate of increase in quadriceps strength pre- and post-intervention (BFR: median 12.1%, interquartile range -0.8% to 19.5%; LST: median 6.2%, interquartile range 2.7% to 14.7%; p>0.99) or in the rate of reduction in quadriceps strength pre- and post-surgery (BFR: mean -72.4%, standard deviation ±11.2%; LST: mean -75.3%, standard deviation ±12.2%; p=0.57). Safety assessments showed no significant main effects of time, group, or interaction on the safety parameters (all p>0.05). Conclusions LLRT-BFR and LST demonstrated comparable effects on quadriceps strength before and after intervention and surgery in patients undergoing TKA. The lack of significant changes in the safety parameters supports the safety profile of both interventions, indicating their suitability for preoperative conditioning in patients scheduled for TKA.

Physical fitness and blood parameters outcomes of breast cancer survivor in a low-intensity circuit resistance exercise program.

There is limited evidence regarding the effect of circuit-type low-intensity resistance exercise on physical fitness and blood parameters in breast cancer survivors (BCSs). Therefore, this study aimed to investigate the effect of low-intensity circuit resistance exercise on changes in physical fitness and blood parameters in BCSs. A total of 16 BCSs participated in a low-intensity circuit resistance exercise group (LCREG). The exercise program in the LCREG consisted of 50-60% of one repetition maximum, two to three times weekly, for 24 weeks. The control group (CG) did not receive any interventions. All participants were measured for physical fitness and blood parameters before and after the exercise intervention. The results showed that LCREG significantly improved body mass index (BMI) (p = 0.012), grip strength (p = 0.017), back strength (p = 0.042), plank (p = 0.036), balance (p = 0.030), low-density lipoproteins (LDL) (p = 0.050), total cholesterol (p = 0.017), and natural killer cell activity (NKCA) (p = 0.035) after exercise compared to before exercise. The LCREG also significantly improved BMI (p = 0.001), grip strength (p = 0.014), plank (p = 0.018), balance (p = 0.012), LDL (p = 0.024), total cholesterol (p = 0.012), and NKCA (p = 0.036) compared to the CG. These findings suggest that low-intensity circuit resistance exercise can increase physical fitness levels and improve the blood index in BCSs.

Systematic review on the impact of exercise on intraocular pressure in glaucoma patients.

Due to limited studies, we systematically reviewed evidence on the impact of physical exercise on intraocular pressure (IOP) in glaucoma patients, adhering to PRISMA guidelines. Using MEDLINE/Web of Science, PubMed, and Scopus, we selected English, Portuguese, or Spanish studies excluding case reports and yoga-based interventions. From 1001 records, 15 studies were independently evaluated. Evaluated through the MMAT scoring system, two quantitative randomised controlled studies scored 100% while 13 non-randomised studies averaged 84.62%. Our findings indicated that both aerobic and resistance training led to an immediate IOP reduction post-exercise. However, these findings were largely from single-session experiments. In contrast, the effects of longer-term exercise programmes on IOP varied. Although our review underscores the potential utility of exercise in IOP management, the evidence remains inconclusive due to variations in study design, participant demographics, and exercise parameters. This lack of consistency in the research highlights the necessity for larger, standardised, and longer-term studies to robustly corroborate these preliminary findings.

Effects of resistance training on quality of life, fatigue, physical function, and muscular strength during chemotherapy treatment: a systematic review and meta-analysis.

PURPOSE: To systematically review and meta-analyse the efficacy of resistance training on quality of life (QOL), fatigue, physical function, and muscular strength in people diagnosed with cancer undergoing chemotherapy. METHODS: Electronic databases PubMed, Cochrane Central, CINAHL, SCOPUS and Web of Science were systematically searched for randomised controlled trials (RCTs) that compared the effects of resistance training to control on QOL, fatigue, physical function, and lower-body and upper-body muscular strength in adults undergoing chemotherapy. Standardised mean differences (SMDs) were pooled using a random effects model. Risk of bias was assess using the risk of bias tool for randomised trials (RoB 2). RESULTS: Seven RCTs encompassing 561 participants were included. The pooled results of seven RCTs showed that resistance training during chemotherapy significantly improved lower-body strength (n = 555, SMD 0.33, 95% CI 0.12 to 0.53, moderate-quality evidence, I2 = 23%) compared to control. There was no evidence for an effect of resistance training on QOL (n = 373, SMD 0.13, 95% CI -0.15 to 0.42, low-quality evidence, I2 = 0%), fatigue (n = 373, SMD -0.08, 95% CI -0.37 to 0.22, low-quality evidence, I2 = 20%), physical function (n = 198, SMD 0.61, 95% CI -0.73 to 1.95, very low-quality evidence, I2 = 83%), or upper-body strength (n = 413, SMD 0.37, 95% CI -0.07 to 0.80, very low-quality evidence, I2 = 69%). CONCLUSIONS: Resistance training may improve lower-body strength in patients undergoing chemotherapy treatment compared to control.

Effects of aerobic exercise and resistance training on obstructive sleep apnea: a systematic review and meta-analysis.

STUDY OBJECTIVES: We investigated the therapeutic effects of exercise in patients with obstructive sleep apnea (OSA), aiming to identify the subgroups that benefit the most and determine the optimal exercise protocol. METHODS: Major databases were searched for randomized controlled trials involving patients with OSA performing aerobic exercise and/or resistance training. The investigated outcomes included apnea-hypopnea index (AHI), Epworth Sleepiness Scale (ESS), body mass index (BMI), and peak oxygen consumption during exercise (VO2peak). The pre- and postintervention unstandardized mean difference (USMD) of these parameters was compared between the exercise and control groups. RESULTS: Twelve studies involving 526 patients were included. Exercise training significantly reduced AHI (USMD = -7.08 events/hour, 95% confidence interval [CI]: -9.98 to -4.17, p < 0.00001), ESS (USMD = -2.37, CI: -3.21 to -1.54, p < 0.00001), and BMI (USMD = -0.72 kg/m2, CI: -1.22 to -0.22, p = 0.005) and enhanced VO2peak (USMD = 3.46 mL/kg/min, CI: 1.20 to 5.71, p = 0.003). Subgroup analyses revealed that in continuous positive airway pressure (CPAP)-adherent patients, exercise significantly improved VO2peak but did not reduce AHI and ESS. A trend was observed that combining resistance training with aerobic exercise resulted in greater AHI reduction and VO2peak enhancement. Notably, exercise improved AHI, ESS, BMI, and VO2peak regardless of the baseline AHI or BMI. CONCLUSIONS: Exercise, including resistance and aerobic training, should be part of treatment for patients with OSA of all severities, regardless of obesity status, and even for those who are already under CPAP. SYSTEMATIC REVIEW REGISTRATION: The study protocol was registered with the PROSPERO database (#CRD42023423527).

Reliability of dynamic and isometric upper muscle strength testing in breast cancer survivors.

Breast cancer is the most common cancer in women worldwide, and its treatment usually involves a combination of many medical procedures, including surgery, chemotherapy, radiotherapy, and hormonal therapy. One of the detrimental effects on physical function is reduced upper limb muscle strength. This study aimed to evaluate upper body strength intra-day and inter-day (test-retest) reliability using the handgrip strength test (HGS) and the bilateral isometric bench press (BIBP) and the test-retest reliability of the one repetition maximum on the bench press (BP-1RM) in breast cancer survivors (BCS). Thirty-two (52.94 ± 8.99 yrs) BCS participated in this study. The muscle strength tests were performed in two different moments, three to seven days apart. Intraclass coefficient correlation (ICC) and coefficient of variation (CV) were used to assess the reliability. Standard error of measurement (SEM), typical error of measurement (TEM), and minimally detectable change (MDC) analyses were performed. The Bland-Altman analysis was used to assess the agreement between test-retest. We found a reliability that can be described as "high" to "very high" (ICC ≥ 0.88; CV ≤ 10%) for intra-day and test-retest. SEM% and MDC% were lower than 5% and 11%, respectively, for all intra-day testing. SEM% and TEM% ranged from 3% to 11%, and MDC% ranged from 9% to 23% in the test-retest reliability. The agreement demonstrated a systematic bias ranging from 2.3% to 6.0% for all testing, and a lower systematic bias may be presented in the non-treated side assessed by HGS and BIBP. HGS, BIBP, and BP-1RM assessments are reliable for measuring upper-body muscle strength in BCS.

Resistance training modalities: comparative analysis of effects on physical fitness, isokinetic muscle functions, and core muscle biomechanics.

Introduction: This study aimed to evaluate the effects of varied resistance training modalities on physical fitness components, body composition, maximal strength assessed by one-repetition maximum (1RM), isokinetic muscle functions of the shoulder and knee joints, and biomechanical properties of core muscles. Methods: Forty participants were randomly assigned to four groups: control group (CG, n = 10), compound set training group (CSG, n = 10), pyramid set training group (PSG, n = 10), and superset training group (SSG, n = 10). Excluding the CG, the other three groups underwent an 8-week resistance training program, three sessions per week, at 60%-80% of 1RM intensity for 60-90 min per session. Assessments included body composition, physical fitness components, 1RM, isokinetic muscle functions, and biomechanical properties (muscle frequency, stiffness, etc.) of the rectus abdominis and external oblique muscles. Results: The PSG demonstrated the most significant improvement in relative peak torque during isokinetic testing of the shoulder and knee joints. Compared to the CG, all exercise groups exhibited positive effects on back strength, sprint performance, 1RM, and core muscle biomechanics. Notably, the PSG showed superior enhancement in external oblique stiffness. However, no significant differences were observed among the exercise groups for rectus abdominis biomechanical properties. Discussion: Structured resistance training effectively improved maximal strength, functional performance, and core muscle biomechanics. The pyramidal training modality conferred specific benefits for isokinetic muscle functions and external oblique stiffness, suggesting its efficacy in enhancing force production capabilities and core stability.

5'-UMP inhibited muscle atrophy due to detraining: a randomized, double-blinded, placebo-controlled, parallel-group comparative study.

Purpose: A short period of disuse of 1-2 weeks due to factors such as illness or injury can lead to muscle atrophy, affecting both athletic performance and health. Recent research has shown that uridine 5'-monophosphate (5'-UMP) can counteract disuse-induced muscle atrophy by increasing PGC-1α expression and inhibiting atrogin-1 expression. However, the effect of 5'-UMP on disuse muscle atrophy in humans remains unknown. Therefore, the aimed of this study was to explore the effects of 5'-UMP supplementation during detraining on short-term disuse muscle atrophy in healthy men. Methods: Following a 6-week resistance training program on upper arm, healthy men were randomized to either a UMP group (n = 11) or a placebo group (n = 10), taking their respective supplements during the 2-week detraining period. Muscle thickness, an indicator of muscle hypertrophy and atrophy, was measured at 3 positions (MT50, MT60, and MT70) at baseline, 1 week, and 2 weeks after detraining. Results: Both groups showed a significant decrease in muscle thickness at MT70. The relative decrease was greater in the placebo group (2.4 ± 2.8%) than in the UMP group (0.0 ± 2.0%), significantly (p = 0.034) at 1 week. However, no significant difference was observed at MT50 and MT60. Conclusion: After the hypertrophy, 5'-UMP may prevent muscle atrophy due to the detraining within the first week.

EmpowerHER: A Pilot Study to Increase Physical Activity and Strength Through Powerbuilding.

Engaging in empowering exercise develops movement competency (MC) and strength and supports physical health, mental well-being, and quality of life. Powerbuilding combines powerlifting and bodybuilding to increase physical activity (PA), MC, and strength. To our knowledge, powerbuilding has not been explored as an exercise intervention. This pilot study investigated the impact of an eight-week powerbuilding intervention on women's PA, MC, strength, and empowerment. Eighteen women aged 25.1±9.8 with no powerbuilding experience participated in the intervention, meeting three times weekly for one hour. PA and MC were assessed pre- and post-intervention. Three-repetition maximum (3-RM) tests in the squat, bench press, and deadlift were completed in weeks one and eight of the intervention. Data were checked for normality; the Wilcoxon signed-rank test was used for non-normally distributed data. The McNemar test was used to analyze differences in dichotomous variables. Effect size was calculated and interpreted as follows small (r=0.1, d=0.2, ω=0.1), medium (r=0.3, d=0.5, ω=0.3), and large (r=0.5, d=0.8, ω=0.5) Total PA ([t(17)=3.52, p=0.003, d=0.83]) and participants who met the PA guidelines (Z=6.13, p=0.008, ω=0.82) increased significantly from pre- to post-intervention. Participants' MC scores improved significantly from pre- (24.3±3.5) to post-intervention (29.5±2.5; [t(17)=10.04, p<0.001; d=2.37]). Significant increases in strength were observed (squat [Z=-3.73, p<0.001, r=0.88], bench press [Z=-3.73, p<0.001, r=0.88], and deadlift [t(17)=16.41, p<0.001; d=3.87]). Empowerment in exercise scores averaged 56.3±6.6 (on a scale of 5-65). The intervention significantly increased total PA, improved MC, increased strength, and facilitated empowerment. Women's participation in powerbuilding may enhance their quality of life.