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.

Sleep pathology and use of anabolic androgen steroids among male weightlifters in Norway.

Use of anabolic androgenic steroids (AAS) causes drastic changes in hormonal milieu and is associated with a range of medical and psychological consequences. Sleep pathology is a common side-effect of AAS use but few have studied these relations. This study examined the relationship between AAS use, psychological distress and sleep quality, and how phases of heavy use and abstinence influence sleep. The Pittsburgh-Sleep-Quality-Index (PSQI) and Jenkins Sleep Scale (JSS) were used to assess sleep quality, and psychological distress was measured with the Hopkins Symptoms Checklist (HSCL). Participants comprised men who have previous or current long-term use of AAS (n = 68) and non-using weightlifting controls (WLC) (n = 58), where a subgroup of participants (n = 22) was monitored over ~ 6 months during phases of AAS use and withdrawal. Group differences on PSQI and JSS were evaluated with Kruskal-Wallis H tests, and the mediating role of psychological distress was evaluated using structural equation modeling. Linear mixed models were used to assess the role of AAS use and withdrawal on sleep quality. Among the AAS group, 66% reported sleep problems as a side effect, and 38% had used sleep medication. PSQI scores showed significantly lower sleep quality in the AAS group compared to WLC (p < 0.001) on all subscales except "sleep latency". Furthermore, sleep quality was significantly poorer during withdrawal-phases than periods with AAS use (p < .001). Our findings provide key insight into sleep disturbances among men who use AAS, suggesting a link between sleep disturbances and hormone levels that deviate from physiologically normal levels in both directions.

Intuitive tracking: Blending competing approaches to exercise and eating.

Under the conditions of neo-liberal individual responsibilisation, self-tracking has become the predominant model of health management. More recently, though, intuition-based approaches to exercise and eating are also gaining traction. These two approaches are often located in opposition. While self-tracking uses datafication and calculability to structure health decisions, intuitive approaches encourage abandonment of rules and restrictions around exercise and food in favour of corporeal self-awareness and attunement to sensation. Although navigating these competing approaches is a common experience for all populations, the tensions between them are felt particularly acutely by people with complex health histories, such as eating disorders (EDs). In this article, we draw on mixed-methods longitudinal data, analysed using phenomenological analysis, to propose a novel framework - 'intuitive tracking'-which moves beyond understandings of self-tracking as the antithesis of intuitive engagement with exercise and health. Drawing on longitudinal interviews and photo elicitation with 19 women who are in recovery from EDs and using weightlifting as a tool to support their recovery, we demonstrate how attentiveness to bodily and emotional cues is successfully combined with an emphasis on monitoring health behaviours to support wellbeing. We conclude that theoretical understandings of self-tracking can and should make space for intuition-led decision-making.

The effects of anti-doping measures on sports performance in weightlifting.

BACKGROUND: Evaluating anti-doping measures is essential to optimise their effectiveness. Comparing sporting results that have a higher doping prevalence, such as weightlifting, before and after the implementation of anti-doping measures may serve as an effectiveness indicator. METHODS: The results of the most successful weightlifters of both sexes in two time periods, 2009-2015 and 2016-2022 were analysed. The Sinclair Total (ST) to compare the relative strength of weightlifters from different weight categories was calculated. RESULTS: A significant decrease in the ST during 2016-2022 (p < 0.001) in athletes of all ages and both sexes overall was reported. When analysed by age, there was a decrease in ST in juniors and seniors of both sexes (p = 0.010 and p < 0.001, respectively), but not in youth. There was a decrease in the ST in senior men (p < 0.001), junior women (p < 0.001) and senior women (p < 0.001). CONCLUSION: In elite weightlifting, adult athletic results declined during 2016-2022, which may partly be explained by the implementation of new methods to detect long-term anabolic androgenic steroid metabolites as well as other policies. This may highlight the effectiveness of these methods both in the prevention and detection of anti-doping rule violations.

Increased mitochondrial surface area and cristae density in the skeletal muscle of strength athletes.

Mitochondria are the cellular organelles responsible for resynthesising the majority of ATP. In skeletal muscle, there is an increased ATP turnover during resistance exercise to sustain the energetic demands of muscle contraction. Despite this, little is known regarding the mitochondrial characteristics of chronically strength-trained individuals and any potential pathways regulating the strength-specific mitochondrial remodelling. Here, we investigated the mitochondrial structural characteristics in skeletal muscle of strength athletes and age-matched untrained controls. The mitochondrial pool in strength athletes was characterised by increased mitochondrial cristae density, decreased mitochondrial size, and increased surface-to-volume ratio, despite similar mitochondrial volume density. We also provide a fibre-type and compartment-specific assessment of mitochondria morphology in human skeletal muscle, which reveals across groups a compartment-specific influence on mitochondrial morphology that is largely independent of fibre type. Furthermore, we show that resistance exercise leads to signs of mild mitochondrial stress, without an increase in the number of damaged mitochondria. Using publicly available transcriptomic data we show that acute resistance exercise increases the expression of markers of mitochondrial biogenesis, fission and mitochondrial unfolded protein responses (UPRmt ). Further, we observed an enrichment of the UPRmt in the basal transcriptome of strength-trained individuals. Together, these findings show that strength athletes possess a unique mitochondrial remodelling, which minimises the space required for mitochondria. We propose that the concurrent activation of markers of mitochondrial biogenesis and mitochondrial remodelling pathways (fission and UPRmt ) with resistance exercise may be partially responsible for the observed mitochondrial phenotype of strength athletes. KEY POINTS: Untrained individuals and strength athletes possess comparable skeletal muscle mitochondrial volume density. In contrast, strength athletes' mitochondria are characterised by increased cristae density, decreased size and increased surface-to-volume ratio. Type I fibres have an increased number of mitochondrial profiles with minor differences in the mitochondrial morphological characteristics compared with type II fibres. The mitochondrial morphology is distinct across the subcellular compartments in both groups, with subsarcolemmal mitochondria being bigger in size when compared with intermyofibrillar. Acute resistance exercise leads to signs of mild morphological mitochondrial stress accompanied by increased gene expression of markers of mitochondrial biogenesis, fission and mitochondrial unfolded protein response (UPRmt ).

Impact of heavy resistance training on pregnancy and postpartum health outcomes.

INTRODUCTION AND HYPOTHESIS: Participation in Olympic weightlifting, the Valsalva maneuver, and acute or prolonged supine weightlifting during pregnancy are cautioned against; however, these recommendations are based on expert opinions as opposed to empirical evidence. The aim of this study was to examine the training and health outcomes of individuals who engaged in heavy resistance training during pregnancy. METHODS: A total of 679 individuals who lifted at least 80% one-repetition maximum during pregnancy participated in an online survey. RESULTS: Participants were primarily recreational athletes (88%, 332 out of 675) engaged in CrossFit™ (61%, 410 out of 675) and/or weightlifting (49%, 332 out of 675) during pregnancy. Most participants reported no complications during pregnancy or delivery (66%, 388 out of 589), whereas 57% (241 out of 426) reported urinary incontinence following pregnancy. Participants who maintained pre-pregnancy training levels until delivery reported significantly less reproductive complications than those who ceased training levels prior to delivery (p = 0.006). Most respondents engaged in Olympic lifting (72%, 311 out of 432) and lifting in a supine position (71%, 306 out of 437), whereas fewer reported use of the Valsalva maneuver during pregnancy (34%, 142 out of 412). Most returned to weightlifting following delivery (89%, 400 out of 447, average: 3.2 ± 3.0 months), including Olympic lifting (81%, 300 out of 372, average: 4.0 ± 3.4 months) and Valsalva (62%, 213 out of 341, average: 4.5 ± 3.6 months). CONCLUSIONS: Individuals who engaged in heavy prenatal resistance training had typical perinatal and pelvic floor health outcomes that were not altered whether they engaged in, or avoided Olympic lifting, Valsalva or supine weightlifting.

Arthralgia in female Masters weightlifters.

BACKGROUND: Arthralgia or joint pain is a heterogeneous condition including organic and nonorganic joint pain. It is common in older populations, particularly in females. There is evidence that menopausal changes are associated with increased prevalence of arthralgia. While physical activities have been recommended to mitigate osteoarthritis (OA) and arthralgia, sport participation also carries risk factors due to excessive loading of some joints and possible injuries. The aim was to evaluate the association of training patterns, prior injuries, and severity of menopausal symptoms with arthralgia in female Masters weightlifters. METHODS: Competitive female Masters weightlifters (n=868, 30-78 years) from 30 countries completed an online survey including joint pain for different anatomical sites, weightlifting training and performance, sport history, and menopausal symptoms. Logistic regression models were used to estimate the association of training patterns, prior sport participation, and menopausal symptom severity with arthralgia separately for shoulders, spine, hips, knees, ankles, elbows, and hands. RESULTS: Arthralgia was most reported in knees (38.8%), shoulders (29.8%), hands/wrists (28.8%), and hips (24.9%). The prevalence of arthralgia was 51.5% in pre-menopausal women, 62.4% in women post natural menopause and 73.3% in women post medical or surgical menopause. Lifting heavier weights was associated with arthralgia in hips (OR=1.05, p=0.03), knees (OR=1.06, p=0.01), and hands/wrists (OR=1.05, p=0.04), but prior strength training was protective for arthralgia in the shoulders (OR=0.66, p=0.02). Prior injuries and psychological menopausal symptom severity were associated with an increased risk for arthralgia (p<0.01). CONCLUSIONS: Arthralgia was common in competitive female weightlifters. Training frequency was not associated with arthralgia, but lifting heavier weights relative to age and body mass was. Prior injuries and menopausal symptoms were associated with arthralgia, but prior strength training was protective of arthralgia in the shoulders. Athletes, coaches and sports medicine professionals should be aware that prevalence of polyarthralgia increases in post-menopausal athletes.

Pectoralis major rupture in body builders: a case series including anabolic steroid use.

BACKGROUND: Rupture of the pectoralis major (PM) muscle is a rare injury, with increasing incidence over the last decades, mainly due to participation in weightlifting and contact sports. Surgical management of PM injuries has been related with superior functional outcome, faster return to activities, better cosmesis and higher level of patients' satisfaction. The aim of the study is to present our experience in the management of this rare clinical entity and to correlate the use of anabolic steroids in the occurrence of the injury and the impact of type of injury, method of reconstruction and anabolic steroids on the post-operative outcome. CASES: We present a series of six male bodybuilding athletes who sustained PM rupture during weightlifting. We recorded the location & type of injury, the history and type of anabolic steroids use, the method of repair and the post-operative outcome. TREATMENT AND OUTCOMES: The mean follow-up period was 16 (12-24) months. All patients treated surgically had excellent results according to Bak criteria and returned to full activity within 5.4 (5-7) months following surgical reconstruction. No post-operative complications were recorded, despite the continued use of anabolic steroids, however one patient died from myocardial infarction within a year of surgical treatment. CONCLUSIONS: PM rupture is an injury with increasing incidence within bodybuilding athletes probably not related to the dominance of the limb. Fixation of the tendon with suture anchors results in excellent clinical outcome and patient's satisfaction postoperatively regardless the chronicity of the repair. Our observations in these cases suggest that anabolic steroids use may contribute to the injury due to an excessive upward adjustment of the athlete's goals in lifting weights and moreover the continuation of administration even in the recovery period does not seem to have a negative effect either on the time or on the level of adequate functional recovery postoperatively.

Differences in muscle synergies between skilled and unskilled athletes in power clean exercise at various loads.

The purpose of this study was to determine the differences in muscle synergy between skilled and unskilled participants using various loading conditions for power clean. Nineteen participants (ten skilled and nine unskilled) performed power clean at 60-90% one repetition maximum (1RM), while measured 12 muscles across the entire body. The vertical impulse was calculated for the unweighting associated with the double-knee bend (DKB) manoeuvre in power clean. Muscle synergies were extracted using non-negative matrix factorization. The weighting of muscle synergies was subsequently compared between the two groups for all loads, and confidence intervals were calculated. The number of muscle synergies in both groups was three, and the functions of all muscle synergies were similar. Muscle synergy 1 involved the first pull, muscle synergy 2 involved the transition and the second pull, and muscle synergy 3 involved DKB. No significant difference in either muscle synergy was observed at 60-80% 1RM weight, while the 90% 1RM showed significantly active in the ankle plantar flexor and knee extensor muscles for muscle synergy 3, which involved DKB only in the skilled group. This indicates that increased joint stiffness during DKB may minimize unweighting. Unskilled individuals may acquire such muscle synergies to lift greater weights.

Effects of Low-Load, High-Repetition Resistance Training on Maximum Muscle Strength and Muscle Damage in Elite Weightlifters: A Preliminary Study.

This study aimed to assess the impact of different resistance training (RT) loads and repetition on muscle damage, intramuscular anabolic signaling, and maximal muscle strength (MMS) in weightlifters. Eighteen male weightlifters were randomly assigned to 8 weeks of supervised RT regimes: high-load, low-repetition (HL), low-load, high-repetition (LH), and combination of HL and LH (COMBI). All groups exhibited a significant increase in skeletal muscle mass (SMM) and growth hormone levels, which ultimately contributed to improvement in MMS as indicated by 1-repetition maximum in the back squat and back muscle strength. Notably, while there were no significant changes in the mTOR protein, the phosphorylation of phosphorylation of p70 ribosomal protein S6 kinase 1 (p70S6K1), eukaryotic initiation factor 4E-binding protein 1 (4E-BP1), and eukaryotic elongation factor 2 (eEF2), which are involved in muscle cell growth, was significantly affected by the different training regimens. More importantly, LH-RT led to a significant reduction in muscle damage markers, creatine kinase (CK) and lactate dehydrogenase (LDH), suggesting reduced recovery time and fatigue. Our results demonstrated that the LH-RT paradigm could be a viable alternative for weightlifters to enhance MMS and muscle hypertrophy similar to HL-RT, while reducing RT-induced muscle damage, ultimately contributing to the enhancement of exercise performance.

Quadriceps Function and Athletic Performance in Highly Trained Female Athletes.

CONTEXT: Quadriceps strength is considered a key contributor to performance in various athletic tasks. Yet, past research has reported conflicting results based on population, with little data available in highly trained female athletes. DESIGN: Cross-sectional. METHOD: To examine how athletic performance relates to quadriceps strength and neural function, we measured the quadriceps maximum voluntary isometric contraction force (MVIC) and rate of force development over 0 to 50 ms (rate of force development [RFD]0-50ms), and various performance measures in 34 highly trained female athletes. RESULTS: Stepwise multiple regression analysis revealed that the quadriceps variables explained 16 of 21 performance variables (R2 = .08-.36, P ≤ .10). Squat performance related to RFD0-50ms alone (R2 = .17-.20, P < .05; ßRFD = 0.41 to 0.45, P < .05) but only MVIC explained the variance in sprinting and vertical jump performance (R2 = .08-.34, P ≤ .10; ßMVIC = -0.51 to 0.58, P ≤ .10). The broad jump model included both parameters and their interaction (R2 = .20, P = .08; ßRFD = 0.06, P = .76; ßMVIC = -0.39, P = .03; ßRFD×MVIC = -0.24, P = .10). CONCLUSION: The contribution of the quadriceps MVIC or RFD0-50ms varies in size and nature depending on the task or leg dominance. While quadriceps are significant contributors to performance, because our models leave most of the variance in performance unexplained, rehabilitation and performance professionals should refrain from interpreting peak athletic performance as a reflection of knee-extensors function in highly trained female athletes.

Effects of Expertise on Muscle Activity during the Hang Power Clean and Hang Power Snatch Compared to Snatch and Clean Pulls - An Explorative Analysis.

The purpose was to compare the electromyographic (EMG) activity of the Hang Power Clean (HPC) and Hang Power Snatch (HPS) with the Hang Clean Pull (HCP) and Hang Snatch Pull (HSP). Additionally, the influence of weightlifting expertise (beginner, advanced and elite) on EMG activity was analyzed. Twenty-seven weightlifters (beginner: n = 11, age: 23.9 ± 3.2 years, bodyweight: 75.7 ± 10.5 kg; advanced: n = 10, age: 24.8 ± 4.5 years, bodyweight: 69.4 ± 13.9 kg; elite: n = 6, age: 25.5 ± 5.2 years, bodyweight: 75.5 ± 12.5 kg) participated in this study. Participants performed two repetitions of HPC, HPS, HCP, and HSP at 50%, 70%, and 90% 1RM, respectively. The EMG activity of vastus lateralis (VL), gluteus maximus (GM), erector spinae (ES), rectus abdominis (RA) and trapezius (TZ) was recorded and normalized to the maximum voluntary isometric contraction (MVIC) of each muscle. There were significant differences in RA and ES EMG activity at 70% and 90% 1RM during HPC compared to HCP in the beginner group (p < 0.05, Hedges g = 0.50-1.06). Significant greater ES activity was observed in the beginner, advanced, and elite groups (p < 0.05, g = 0.27-0.98) during the HPS when compared to the HSP at 50-90% 1RM. TZ muscle activity was significantly greater at 50% and 70% 1RM in the HCP compared to the HPC in the elite group (p < 0.05, g = 0.61-1.08), while the beginner group reached significance only at 50% 1RM favoring HPC (p < 0.05, g = 0.38). Moreover, the EMG activity of the TZ during the HSP and HPS was significantly different only at 50% 1RM in the elite group and favored HSP (p < 0.05, g = 0.27). No differences were observed between the levels of weightlifting expertise. Based upon the results of this study, the overall pattern of EMG activity of the predominant muscles involved in HPC/HPS and the corresponding weightlifting pulling derivatives, apart from the stabilizing muscle (RA and ES), is similar at higher intensities (>70% 1RM) and expertise does not influence muscle activity.

Resistance training for Black men with depressive symptoms: a pilot randomized controlled trial to assess acceptability, feasibility, and preliminary efficacy.

BACKGROUND: Depression is under-recognized in Black men, who are less likely to seek or have access to psychiatric treatment. Resistance training (RT; i.e., weight lifting) can improve depressive symptoms and may be more acceptable to Black men, but its effects have not been examined for Black men with depressive symptoms. METHODS: Fifty Black men with depressive symptoms were randomized to either (a) 12 weeks of RT (coupled with Behavioral Activation techniques to promote adherence) or (b) an attention-control group (Health, Wellness, and Education; HWE). Both groups met twice/week for 12 weeks, and follow-up assessments were done at end-of-treatment (EOT) and 6 months after enrollment. Changes in physical activity and muscular strength were collected as a manipulation check. The primary outcome was interviewer assessed symptoms of depression using the Quick Inventory of Depression Symptomology (QIDS). Secondary outcomes included self-reported depressive symptoms, anxiety, and stress. The association between change in QIDS from baseline to EOT and concurrent changes in physical activity and muscular strength in the RT group were explored as an initial assessment of mechanism. Longitudinal mixed effects regression models with subject-specific intercepts were used to examine intervention effects. RESULTS: A sample with high rates of medical comorbidities (e.g., 44% HIV positive), substance use (e.g., 34% smoking), and negative social determinates of health (e.g., 50% unemployed) was enrolled. Recruitment, engagement, and retention data indicate that the intervention and design were feasible. The RT group showed greater gains in self-reported exercise (b = 270.94, SE = 105.69, p = .01) and muscular strength (b = 11.71, SE = 4.23, p = .01 for upper body and b = 4.24, SE = 2.02, p = .04 for lower body) than the HWE group. The RT group had greater reductions in QIDS scores at both EOT (b = -3.00, SE = 1.34, p = .01) and 6 months (b = -2.63, SE = 1.81, p = .04). The RT group showed a greater reduction in anxiety at EOT (b = -2.67, SE = 1.06, p = .02). Findings regarding self-reported depressive symptoms and stress were non-significant, but in the expected direction with effect sizes in the small to medium range. In the RT group, improvement on the QIDS between baseline and EOT was associated with concurrent improvements in physical activity (b = 21.03, SE = 11.16, p = .02) and muscular strength (b = 1.27, SE = .44, p = .03 for upper body and b = .75, SE = .14, p = .03 for lower body). CONCLUSIONS: Results suggest that RT is feasible and may be efficacious for reducing depressive symptoms among underserved urban Black men. TRIAL REGISTRATION: ClinicalTrial.gov #: NCT03107039 (Registered 11/04/2017).

Effects of Different Levels of Weightlifting Training on Bone Mineral Density in a Group of Adolescents.

The aim of the current study was to evaluate the effects of different levels of weightlifting training on bone mineral density (BMD) at different body sites (whole body (WB), lumbar spine (LS), femoral neck (FN), upper limbs (UL) and lower limbs (LL)) in a group of adolescents. Three groups of pubertal boys aged 13-15 years were recruited, including a control group (which included 13 untrained adolescents), a moderately trained group (which included 13 non-elite weightlifters, with four sessions of 2 hours per week) and a highly trained group (which included 13 elite weightlifters, with eight sessions of 2 hours per week). The three groups were paired for age and maturation index (using Tanner stages). Body composition, bone mineral content (BMC) and BMD were evaluated by dual-energy X ray absorptiometry (DXA). Physical performance variables (including weightlifting specific exercises, counter movement jump and squat jump) were measured using validated methods. Results showed that the values of BMD and physical performance variables were greater in the group of elite weightlifters compared to the group of non-elite weightlifters and the control group. In addition, the values of BMD and physical performance variables were higher in the group of the non-elite weightlifters compared to those of the control group. After adjusting for lean mass and squat jump, lumbar spine BMD, FN BMD, UL BMD and LL BMD remained significantly higher in the elite weightlifters' group compared to the two other groups. In conclusion, the current study suggests that elite adolescent weightlifters have greater bone health parameters compared to moderately-trained adolescent weightlifters and untrained adolescents.

Altered countermovement jump force profile and muscle-tendon unit kinematics following combined ballistic training.

Combined heavy- and light-load ballistic training is often employed in high-performance sport to improve athletic performance and is accompanied by adaptations in muscle architecture. However, little is known about how training affects muscle-tendon unit (MTU) kinematics during the execution of a sport-specific skill (e.g., jumping), which could improve our understanding of how training improves athletic performance. The aim of this study was to investigate vastus lateralis (VL) MTU kinematics during a countermovement jump (CMJ) following combined ballistic training. Eighteen young, healthy males completed a 10-week program consisting of weightlifting derivatives, plyometrics, and ballistic tasks under a range of loads. Ultrasonography of VL and force plate measurements during a CMJ were taken at baseline, mid-test, and post-test. The training program improved CMJ height by 11 ± 13%. During the CMJ, VL's MTU and series elastic element (SEE) length changes and velocities increased from baseline to post-test, but VL's fascicle length change and velocity did not significantly change. It is speculated that altered lower limb coordination and increased force output of the lower limb muscles during the CMJ allowed more energy to be stored within VL's SEE. This may have contributed to enhanced VL MTU work during the propulsion phase and an improved CMJ performance following combined ballistic training.

Energy deficiency impairs resistance training gains in lean mass but not strength: A meta-analysis and meta-regression.

Short-term energy deficits impair anabolic hormones and muscle protein synthesis. However, the effects of prolonged energy deficits on resistance training (RT) outcomes remain unexplored. Thus, we conducted a systematic review of PubMed and SportDiscus for randomized controlled trials performing RT in an energy deficit (RT+ED) for ≥3 weeks. We first divided the literature into studies with a parallel control group without an energy deficit (RT+CON; Analysis A) and studies without RT+CON (Analysis B). Analysis A consisted of a meta-analysis comparing gains in lean mass (LM) and strength between RT+ED and RT+CON. Studies in Analysis B were matched with separate RT+CON studies for participant and intervention characteristics, and we qualitatively compared the gains in LM and strength between RT+ED and RT+CON. Finally, Analyses A and B were pooled into a meta-regression examining the relationship between the magnitude of the energy deficit and LM. Analysis A showed LM gains were impaired in RT+ED vs RT+CON (effect size (ES) = -0.57, p = 0.02), but strength gains were comparable between conditions (ES = -0.31, p = 0.28). Analysis B supports the impairment of LM in RT+ED (ES: -0.11, p = 0.03) vs RT+CON (ES: 0.20, p < 0.001) but not strength (RT+ED ES: 0.84; RT+CON ES: 0.81). Finally, our meta-regression demonstrated that an energy deficit of ~500 kcal · day-1 prevented gains in LM. Individuals performing RT to build LM should avoid prolonged energy deficiency, and individuals performing RT to preserve LM during weight loss should avoid energy deficits >500 kcal day-1 .

Effect of watermelon supplementation on exercise performance, muscle oxygenation, and vessel diameter in resistance-trained men.

INTRODUCTION: Watermelon shows promise as an ergogenic aid due to its high concentration of L-citrulline, vitamins, minerals, and antioxidants. PURPOSE: The purpose of this study was to examine the effect of watermelon supplementation on exercise performance, muscle oxygenation, and vessel diameter. METHODS: In a crossover design fashion, 15 resistance-trained men (22.4 ± 2.9 years; 177.5 ± 7.1 cm; 82.7 ± 11.2 kg) were randomly assigned to supplement with either watermelon juice concentrate (WM; 2.2 g·day-1 L-citrulline) or placebo (PL) for 7 days prior to completing an experimental trial consisting of an isometric mid-thigh pull test and acute bench press protocol. Participants completed two sets of two repetitions at 75% 1 repetition maximum (1-RM) with maximum ballistic intent followed by five repetition-maximum (RM) sets at the same load. Barbell velocity and power were measured via linear position transducer during the first two sets, while volume load and muscle oxygenation were quantified during RM sets. Brachial artery diameter and subjective perception measures were assessed at baseline and immediately pre- and post-exercise. RESULTS: Except for a greater percent change in skeletal muscle oxygenation during WM compared to PL on average and across sets (mean difference = + 4.1%, p = 0.033, BF10 = 2.2-54.5), separate traditional and Bayesian analyses of variance with repeated measures, as well as paired-samples t tests for calculated summary measures, revealed no evidence favoring conditional differences in any measure of performance, perception, or muscle oxygenation. CONCLUSION: Short-term watermelon supplementation does not appear to enhance isometric force production, bench press performance, blood vessel diameter, or muscle oxygenation parameters compared to PL in resistance-trained men.

Distal biceps tendon ruptures occur with the almost extended elbow and supinated forearm - an online video analytic study.

BACKGROUND: Distal biceps tendon ruptures can lead to significant restrictions in affected patients. The mechanisms of injury described in scientific literature are based exclusively on case reports and theoretical models. This study aimed to determine the position of the upper extremities and forces involved in tendon rupture through analyzing video recordings. METHODS: The public YouTube.com database was queried for videos capturing a clear view of a distal biceps tendon rupture. Two orthopedic surgeons independently assessed the videos for the activity that led to the rupture, the arm position at the time of injury and the forces imposed on the elbow joint. RESULTS: Fifty-six video segments of a distal biceps rupture were included (55 male). In 96.4%, the distal biceps tendon ruptured with the forearm supinated and the elbow isometrically extended (non-dynamic muscle engagement) (71.4%) or slightly flexed (24%). The most common shoulder positions were adduction (85.7%) and neutral position with respect to rotation (92.9%). Most frequently a tensile force was enacted on the elbow (92.9%) and the most common activity observed was deadlifting (71.4%). CONCLUSION: Distal biceps tendon ruptures were most commonly observed in weightlifting with a slightly flexed or isometrically extended elbow and forearm supination. These observations may provide useful information for sports specific evidence-based injury prevention, particularly in high performing athletes and individuals engaged in resistance training. LEVEL OF EVIDENCE: Observational study.

Improved power clean performance with the hook-grip is not due to altered force-time or horizontal bar-path characteristics.

he underlying biomechanical benefits of hook-grip (HG) over conventional closed-grip (CG) remain unclear. This study compared bar-path kinematics and force-time variables of the power clean (PC) performed with HG or CG. We also aimed to compared kinetic changes measured by force platform versus linear position transducer (LPT). Eleven well-trained men volunteered. Following a familiarisation session, HG, and CG 1RM conditions, were randomly completed seven days apart. System kinetics and barbell kinematics were recorded via synchronized force platform+LPT system and two-dimensional motion-capture. Statistical parametric mapping (SPM), analysis of variance, and standardised differences were utilised. The SPM cut-offs were determined via novel combination of force and displacement. No between-condition differences in normalised force-time variables of the pull or catch were detected. The first and second pull duration was similar between conditions (ES = 0.04-0.38). Conversely, catch and total PC durations were shorter at 80-95% (ES = 0.26-0.75), with the weightless phase more prolonged at 95% and 100% (ES = 0.54-0.76) with HG compared to CG. Improved timing of the turnover and catch phases appears to be the primary difference between HG and CG performance. Thus, grip type is possibly irrelevant to non-weightlifting athletes when performing submaximal catch-less derivatives..

Comparing biomechanical time series data across countermovement shrug loads.

The effect of load on time-series data has yet to be investigated during weightlifting derivatives. This study compared the effect of load on the force-time and velocity-time curves during the countermovement shrug (CMS). Twenty-nine males performed the CMS at relative loads of 40%, 60%, 80%, 100%, 120%, and 140% one repetition maximum (1RM) power clean (PC). A force plate measured the vertical ground reaction force (VGRF), which was used to calculate the barbell-lifter system velocity. Time-series data were normalized to 100% of the movement duration and assessed via statistical parametric mapping (SPM). SPM analysis showed greater negative velocity at heavier loads early in the unweighting phase (12-38% of the movement), and greater positive velocity at lower loads during the last 16% of the movement. Relative loads of 40% 1RM PC maximised propulsion velocity, whilst 140% 1RM maximized force. At higher loads, the braking and propulsive phases commence at an earlier percentage of the time-normalized movement, and the total absolute durations increase with load. It may be more appropriate to prescribe the CMS during a maximal strength mesocycle given the ability to use supramaximal loads. Future research should assess training at different loads on the effects of performance.