Fair AI-powered orthopedic image segmentation: addressing bias and promoting equitable healthcare.

AI-powered segmentation of hip and knee bony anatomy has revolutionized orthopedics, transforming pre-operative planning and post-operative assessment. Despite the remarkable advancements in AI algorithms for medical imaging, the potential for biases inherent within these models remains largely unexplored. This study tackles these concerns by thoroughly re-examining AI-driven segmentation for hip and knee bony anatomy. While advanced imaging modalities like CT and MRI offer comprehensive views, plain radiographs (X-rays) predominate the standard initial clinical assessment due to their widespread availability, low cost, and rapid acquisition. Hence, we focused on plain radiographs to ensure the utilization of our contribution in diverse healthcare settings, including those with limited access to advanced imaging technologies. This work provides insights into the underlying causes of biases in AI-based knee and hip image segmentation through an extensive evaluation, presenting targeted mitigation strategies to alleviate biases related to sex, race, and age, using an automatic segmentation that is fair, impartial, and safe in the context of AI. Our contribution can enhance inclusivity, ethical practices, equity, and an unbiased healthcare environment with advanced clinical outcomes, aiding decision-making and osteoarthritis research. Furthermore, we have made all the codes and datasets publicly and freely accessible to promote open scientific research.

HexAI-TJAtxt: A textual dataset to advance open scientific research in total joint arthroplasty.

Total joint arthroplasty (TJA) is the most common and fastest inpatient surgical procedure in the elderly, nationwide. Due to the increasing number of TJA patients and advancements in healthcare, there is a growing number of scientific articles being published in a daily basis. These articles offer important insights into TJA, covering aspects like diagnosis, prevention, treatment strategies, and epidemiological factors. However, there has been limited effort to compile a large-scale text dataset from these articles and make it publicly available for open scientific research in TJA. Rapid yet, utilizing computational text analysis on these large columns of scientific literatures holds great potential for uncovering new knowledge to enhance our understanding of joint diseases and improve the quality of TJA care and clinical outcomes. This work aims to build a dataset entitled HexAI-TJAtxt, which includes more than 61,936 scientific abstracts collected from PubMed using MeSH (Medical Subject Headings) terms within "MeSH Subheading" and "MeSH Major Topic," and Publication Date from 01/01/2000 to 12/31/2022. The current dataset is freely and publicly available at https://github.com/pitthexai/HexAI-TJAtxt, and it will be updated frequently in bi-monthly manner from new abstracts published at PubMed.

The Effects of Training Load During Dietary Intervention Upon Fat Loss: A Randomized Crossover Trial.

Purpose: To date no studies have compared resistance training loading strategies combined with dietary intervention for fat loss. Methods: Thus, we performed a randomised crossover design comparing four weeks of heavier- (HL; ~80% 1RM) and lighter-load (LL; ~60% 1RM) resistance training, combined with calorie restriction and dietary guidance, including resistance trained participants (n=130; males=49, females=81). Both conditions performed low-volume, (single set of 9 exercises, 2x/week) effort matched (to momentary failure), but non-work-matched protocols. Testing was completed pre- and post-each intervention. Fat mass (kg) was the primary outcome, and a smallest effect size of interest (SESOI) was established at 3.3% loss of baseline bodyweight. Body fat percentage, lean mass, and strength (7-10RM) for chest press, leg press, and pull-down exercises were also measured. An 8-week washout period of traditional training with normal calorie interspersed each intervention. Results: Both interventions showed small statistically equivalent (within the SESOI) reductions in fat mass (HL: -0.67 kg [95%CI -0.91 to 0.42]; LL: -0.55 kg [95%CI -0.80 to -0.31]) which were also equivalent between conditions (HL - LL: -0.113 kg [95%CI -0.437 kg to 0.212 kg]). Changes in body fat percentage and lean mass were also minimal. Strength increases were small, similar between conditions, and within a previously determined SESOI for the population included (10.1%). Conclusions: Fat loss reductions are not impacted by resistance training load; both HL and LL produce similar, yet small, changes to body composition over a 4-week intervention. However, the maintenance of both lean mass and strength highlights the value of resistance training during dietary intervention.

Postoperative infection and bone sarcoma survival: systematic review of the role of infection in bone sarcoma prognosis.

Background: Osteosarcoma (OS) and chondrosarcoma (CS) are primary bone malignancies whose prognoses have stagnated despite advancements in surgical management, chemotherapy, radiation therapy, and immunotherapy. The role of the immune system in generating anti-cancer physiologic responses is critical to prognosis. Prior studies have explored if immune system activation via infection enhances survival in bone sarcomas without a clear consensus. Methods: This study sought to (I) retrospectively examine the effect of postoperative infection on survival in OS and CS and (II) systematically review the effect of postoperative infection on survival in primary bone malignancies. We performed a retrospective case-control study of 192 patients treated between 1/2000-12/2015 at a single academic sarcoma referral center. Patients with OS or CS undergoing operative resection were included. Eligible patients were grouped by presence of metastasis, and survival was compared between patients with or without postoperative infection. Furthermore, we performed a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines investigating the effect of infection on primary bone malignancy survival. Risk of bias assessment was performed utilizing the ROBINS-I (Risk of Bias in Non-randomized Studies-of Interventions) assessment tool. All presented studies included author information, study population, and overall or disease-free survival results. Results: One hundred and four patients were included, with 85 without infection (26 metastatic, 59 non-metastatic) and 19 with infection (10 metastatic, 9 non-metastatic). Five-year survival was greatest in patients without metastasis with a postoperative infection (100%), followed by patients without metastasis who were infection-free (80%). Five-year survival was comparatively lower in patients with metastasis who were infection-free (35%) and lowest in patients with metastasis with a postoperative infection (20%). No significant differences were present (P=0.17) on log-rank analysis. Our systematic review collected six studies exploring the impact of infection on primary bone malignancy survival, with two studies reporting significant findings of infection improving survival. Limitations of this review included risk of bias due to confounding, inconsistency comparing outcomes, and differences in patient populations. Conclusions: This retrospective study and systematic review suggests postoperative infection may play a role in modulating immune response to malignancy. Understanding the synergy between anti-pathogen and anti-cancer responses warrants further investigation as an alternative method of targeted cancer treatment.

Short-term supervised virtual training maintains intensity of effort and represents an efficacious alternative to traditional studio-based, supervised strength training.

BACKGROUND: Virtual personal training might represent an uncomplicated, accessible, and time-efficient approach to supervised strength training, particularly under government-imposed lockdown or closure of fitness facilities. However, there appears a dearth of literature evaluating the efficacy of virtual personal training. METHODS: The present project considered two studies considering supervised virtual strength training. Study 1 considered trained participants being supervised one-to-one through traditional resistance exercise sessions in a strength training studio (STUD), compared to a virtual personal training protocol performed using bodyweight resistance exercises (VIRT). This study utilized a crossover design whereby male (n = 13) and female (n = 7) participants were tested for body composition using BodPod, and strength for bench press, leg press, and high-row exercises. Participants were then randomly assigned to 3-weeks of VIRT or 3-weeks of STUD training. Following each 3-week training period, participants had a 1-week period without training whereby mid-intervention testing occurred, after which participants then completed the alternate training intervention. For study 2, we surveyed the client base of a chain of training facilities that had begun offering virtual personal training during lockdown to explore their views on this approach. RESULTS: Strength and body composition changes were similar between groups, however for neither condition did results surpass the smallest meaningful change. The remaining survey data suggests that supervised virtual resistance training yields similar perceptions of effort, motivation, enjoyment, and supervision quality, compared to traditional supervised studio training. CONCLUSION: Based on the current data, it appears that short-term supervised virtual resistance training is as efficacious as traditional supervised studio-based resistance training.

Identifying Information Gaps in Electronic Health Records by Using Natural Language Processing: Gynecologic Surgery History Identification.

BACKGROUND: Electronic health records (EHRs) are a rich source of longitudinal patient data. However, missing information due to clinical care that predated the implementation of EHR system(s) or care that occurred at different medical institutions impedes complete ascertainment of a patient's medical history. OBJECTIVE: This study aimed to investigate information discrepancies and to quantify information gaps by comparing the gynecological surgical history extracted from an EHR of a single institution by using natural language processing (NLP) techniques with the manually curated surgical history information through chart review of records from multiple independent regional health care institutions. METHODS: To facilitate high-throughput evaluation, we developed a rule-based NLP algorithm to detect gynecological surgery history from the unstructured narrative of the Mayo Clinic EHR. These results were compared to a gold standard cohort of 3870 women with gynecological surgery status adjudicated using the Rochester Epidemiology Project medical records-linkage system. We quantified and characterized the information gaps observed that led to misclassification of the surgical status. RESULTS: The NLP algorithm achieved precision of 0.85, recall of 0.82, and F1-score of 0.83 in the test set (n=265) relative to outcomes abstracted from the Mayo EHR. This performance attenuated when directly compared to the gold standard (precision 0.79, recall 0.76, and F1-score 0.76), with the majority of misclassifications being false negatives in nature. We then applied the algorithm to the remaining patients (n=3340) and identified 2 types of information gaps through error analysis. First, 6% (199/3340) of women in this study had no recorded surgery information or partial information in the EHR. Second, 4.3% (144/3340) of women had inconsistent or inaccurate information within the clinical narrative owing to misinterpreted information, erroneous "copy and paste," or incorrect information provided by patients. Additionally, the NLP algorithm misclassified the surgery status of 3.6% (121/3340) of women. CONCLUSIONS: Although NLP techniques were able to adequately recreate the gynecologic surgical status from the clinical narrative, missing or inaccurately reported and recorded information resulted in much of the misclassification observed. Therefore, alternative approaches to collect or curate surgical history are needed.

Heat Shock Factor 1 Directly Regulates Postsynaptic Scaffolding PSD-95 in Aging and Huntington's Disease and Influences Striatal Synaptic Density.

PSD-95 (Dlg4) is an ionotropic glutamate receptor scaffolding protein essential in synapse stability and neurotransmission. PSD-95 levels are reduced during aging and in neurodegenerative diseases like Huntington's disease (HD), and it is believed to contribute to synaptic dysfunction and behavioral deficits. However, the mechanism responsible for PSD-95 dysregulation under these conditions is unknown. The Heat Shock transcription Factor 1 (HSF1), canonically known for its role in protein homeostasis, is also depleted in both aging and HD. Synaptic protein levels, including PSD-95, are influenced by alterations in HSF1 levels and activity, but the direct regulatory relationship between PSD-95 and HSF1 has yet to be determined. Here, we showed that HSF1 chronic or acute reduction in cell lines and mice decreased PSD-95 expression. Furthermore, Hsf1(+/-) mice had reduced PSD-95 synaptic puncta that paralleled a loss in thalamo-striatal excitatory synapses, an important circuit disrupted early in HD. We demonstrated that HSF1 binds to regulatory elements present in the PSD-95 gene and directly regulates PSD-95 expression. HSF1 DNA-binding on the PSD-95 gene was disrupted in an age-dependent manner in WT mice and worsened in HD cells and mice, leading to reduced PSD-95 levels. These results demonstrate a direct role of HSF1 in synaptic gene regulation that has important implications in synapse maintenance in basal and pathological conditions.

The Impact of Coronavirus (COVID-19) Related Public-Health Measures on Training Behaviours of Individuals Previously Participating in Resistance Training: A Cross-Sectional Survey Study.

INTRODUCTION: Understanding the impact of lockdown upon resistance training (RT), and how people adapted their RT behaviours, has implications for strategies to maintain engagement in similar positive health behaviours. Further, doing so will provide a baseline for investigation of the long-term effects of these public health measures upon behaviours and perceptions, and facilitate future follow-up study. OBJECTIVES: To determine how the onset of coronavirus (COVID-19), and associated 'lockdown', affected RT behaviours, in addition to motivation, perceived effectiveness, enjoyment, and intent to continue, in those who regularly performed RT prior to the pandemic. METHODS: We conducted an observational, cross-sectional study using online surveys in multiple languages (English, Danish, French, German, Italian, Portuguese, Slovakian, Swedish, and Japanese) distributed across social media platforms and through authors' professional and personal networks. Adults (n = 5389; median age = 31 years [interquartile range (IQR) = 25, 38]), previously engaged in RT prior to lockdown (median prior RT experience = 7 years [IQR = 4, 12]) participated. Outcomes were self-reported RT behaviours including: continuation of RT during lockdown, location of RT, purchase of specific equipment for RT, method of training, full-body or split routine, types of training, repetition ranges, exercise number, set volumes (per exercise and muscle group), weekly frequency of training, perception of effort, whether training was planned/recorded, time of day, and training goals. Secondary outcomes included motivation, perceived effectiveness, enjoyment, and intent to continue RT. RESULTS: A majority of individuals (82.8%) maintained participation in RT during-lockdown. Marginal probabilities from generalised linear models and generalised estimating equations for RT behaviours were largely similar from pre- to during-lockdown. There was reduced probability of training in privately owned gyms (~ 59% to ~ 7%) and increased probability of training at home (~ 18% to ~ 89%); greater probability of training using a full-body routine (~ 38% to ~ 51%); reduced probability of resistance machines (~ 66% to ~ 13%) and free weight use (~ 96% to ~ 81%), and increased probability of bodyweight training (~ 62% to ~ 82%); reduced probability of moderate repetition ranges (~ 62-82% to ~ 55-66%) and greater probability of higher repetition ranges (~ 27% to ~ 49%); and moderate reduction in the perception of effort experienced during-training (r = 0.31). Further, individuals were slightly less likely to plan or record training during lockdown and many changed their training goals. Additionally, perceived effectiveness, enjoyment, and likelihood of continuing current training were all lower during-lockdown. CONCLUSIONS: Those engaged in RT prior to lockdown these behaviours with only slight adaptations in both location and types of training performed. However, people employed less effort, had lower motivation, and perceived training as less effective and enjoyable, reporting their likelihood of continuing current training was similar or lower than pre-lockdown. These results have implications for strategies to maintain engagement in positive health behaviours such as RT during-restrictive pandemic-related public health measures. PRE-REGISTRATION: https://osf.io/qcmpf . PREPRINT: The preprint version of this work is available on SportRχiv: https://osf.io/preprints/sportrxiv/b8s7e/ .

Expression and prognosis analyses of BUB1, BUB1B and BUB3 in human sarcoma.

Budding Uninhibited By Benzimidazoles are a group of genes encoding proteins that play central roles in spindle checkpoint during mitosis. Improper mitosis may lead to aneuploidy which is found in many types of tumors. As a key mediator in mitosis, the dysregulated expression of BUBs has been proven to be highly associated with various malignancies, such as leukemia, gastric cancer, breast cancer, and liver cancer. However, bioinformatic analysis has not been applied to explore the role of the BUBs in sarcomas. Herein, we investigate the transcriptional and survival data of BUBs in patients with sarcomas using Oncomine, Gene Expression Profiling Interactive Analysis, Cancer Cell Line Encyclopedia, Kaplan-Meier Plotter, LinkedOmics, and the Database for Annotation, Visualization and Integrated Discovery. We found that the expression levels of BUB1, BUB1B and BUB3 were higher in sarcoma samples and cell lines than in normal controls. Survival analysis revealed that the higher expression levels of BUB1, BUB1B and BUB3 were associated with lower overall and disease-free survival in patients with sarcomas. This study implies that BUB1, BUB1B and BUB3 are potential treatment targets for patients with sarcomas and are new biomarkers for the prognosis of sarcomas.

Characterizing Chronic Pain Episodes in Clinical Text at Two Health Care Systems: Comprehensive Annotation and Corpus Analysis.

BACKGROUND: Chronic pain affects more than 20% of adults in the United States and is associated with substantial physical, mental, and social burden. Clinical text contains rich information about chronic pain, but no systematic appraisal has been performed to assess the electronic health record (EHR) narratives for these patients. A formal content analysis of the unstructured EHR data can inform clinical practice and research in chronic pain. OBJECTIVE: We characterized individual episodes of chronic pain by annotating and analyzing EHR notes for a stratified cohort of adults with known chronic pain. METHODS: We used the Rochester Epidemiology Project infrastructure to screen all residents of Olmsted County, Minnesota, for evidence of chronic pain, between January 1, 2005, and September 30, 2015. Diagnosis codes were used to assemble a cohort of 6586 chronic pain patients; people with cancer were excluded. The records of an age- and sex-stratified random sample of 62 patients from the cohort were annotated using an iteratively developed guideline. The annotated concepts included date, location, severity, causes, effects on quality of life, diagnostic procedures, medications, and other treatment modalities. RESULTS: A total of 94 chronic pain episodes from 62 distinct patients were identified by reviewing 3272 clinical notes. Documentation was written by clinicians across a wide spectrum of specialties. Most patients (40/62, 65%) had 1 pain episode during the study period. Interannotator agreement ranged from 0.78 to 1.00 across the annotated concepts. Some pain-related concepts (eg, body location) had 100% (94/94) coverage among all the episodes, while others had moderate coverage (eg, effects on quality of life) (55/94, 59%). Back pain and leg pain were the most common types of chronic pain in the annotated cohort. Musculoskeletal issues like arthritis were annotated as the most common causes. Opioids were the most commonly captured medication, while physical and occupational therapies were the most common nonpharmacological treatments. CONCLUSIONS: We systematically annotated chronic pain episodes in clinical text. The rich content analysis results revealed complexity of the chronic pain episodes and of their management, as well as the challenges in extracting pertinent information, even for humans. Despite the pilot study nature of the work, the annotation guideline and corpus should be able to serve as informative references for other institutions with shared interest in chronic pain research using EHRs.

Natural Language Processing for the Evaluation of Methodological Standards and Best Practices of EHR-based Clinical Research.

The effective use of EHR data for clinical research is challenged by the lack of methodologic standards, transparency, and reproducibility. For example, our empirical analysis on clinical research ontologies and reporting standards found little-to-no informatics-related standards. To address these issues, our study aims to leverage natural language processing techniques to discover the reporting patterns and data abstraction methodologies for EHR-based clinical research. We conducted a case study using a collection of full articles of EHR-based population studies published using the Rochester Epidemiology Project infrastructure. Our investigation discovered an upward trend of reporting EHR-related research methodologies, good practice, and the use of informatics related methods. For example, among 1279 articles, 24.0% reported training for data abstraction, 6% reported the abstractors were blinded, 4.5% tested the inter-observer agreement, 5% reported the use of a screening/data collection protocol, 1.5% reported that team meetings were organized for consensus building, and 0.8% mentioned supervision activities by senior researchers. Despite that, the overall ratio of reporting/adoption of methodologic standards was still low. There was also a high variation regarding clinical research reporting. Thus, continuously developing process frameworks, ontologies, and reporting guidelines for promoting good data practice in EHR-based clinical research are recommended.

The "Journal of Functional Morphology and Kinesiology" Journal Club Series: Utility and Advantages of the Eccentric Training through the Isoinertial System.

We are glad to introduce the first Journal Club of volume five, the first issue. This edition is focused on relevant studies published in the last years in the field of eccentric training, chosen by our editorial board members and their colleagues. We hope to stimulate your curiosity in this field and to share with you the passion for the sport, seen also from a scientific point of view. The editorial board members wish you an inspiring lecture.

Neither repetition duration nor number of muscle actions affect strength increases, body composition, muscle size, or fasted blood glucose in trained males and females.

A key variable within resistance training (RT) is that of repetition duration: the time (seconds) taken to perform the concentric and eccentric muscle actions of a repetition. Research has produced equivocal results with regard to strength and muscle mass increases; many studies have created parity in the number of repetitions, but there has been disparity in the load used and the time under load (TUL). The purpose of this study was to compare load- and TUL-matched groups performing resistance exercise using different repetition durations. Fifty-nine male and female participants were randomized into 3 groups: 2s:4s (n = 18), 10s:10s (n = 20), or a group that performed 30 s of eccentric, 30 s of concentric, and 30 s of eccentric muscle actions (e.g., 1.5 repetitions; n = 21). Participants were supervised in one-on-one RT sessions 2 days/week for 10 weeks. Outcomes were 10 repetitions maximum (RM) and predicted 1RM for chest press, leg press, and pulldown exercises, as well as body composition, upper arm and thigh muscle mass, and fasted blood glucose. Analyses revealed significant increases in strength for all exercises but no between-group differences and no statistically significant time course changes for the other variables. Repetition duration does not affect the increases in strength in trained participants when exercise is performed to momentary failure. Because time constraints and perceived difficulty are often cited as barriers to exercise, it is important to recognize that the low-volume (single-set), machine-based protocol employed herein produced worthwhile strength increases in trained participants.

Intra-articular Triamcinolone Versus Hyaluronate Injections for Low Back Pain With Symptoms Suggestive of Lumbar Zygapophyseal Joint Arthropathy: A Pragmatic, Double-Blind Randomized Controlled Trial.

OBJECTIVE: The aim of the study was to compare hyaluronate with triamcinolone injections in treating chronic low back pain suggestive of lumbar zygopophyseal joint arthropathy. DESIGN: This was a prospective, double-blind, randomized controlled trial. Thirty subjects were randomly assigned to receive bilateral L3-S1 lumbar zygopophyseal joint injections with triamcinolone (KA) or Synvisc-One (HA). Pain (visual analog scale) and Pain Disability Questionnaire scores at 1, 3, and 6 mos were evaluated. RESULTS: No significant intergroup differences (P > 0.05) in outcomes were noted in the 30 recruited subjects. For KA/HA (baseline; 1 mo; 3 mos; 6 mos), visual analog scale scores were the following: 70 (15)/74 (10); 58 (29)/45 (25); 58 (29)/56 (25); and 59 (28)/63 (24), respectively. Pain Disability Questionnaire scores were the following: 100 (23)/102 (28); 77 (30)/74 (34); 87 (26)/74 (36); and 96 (25)/79 (25). Overall percent improvement at 6 mos for KA was 51 (35) and for HA was 42 (33) (P = 0.51). Synvisc-One group visual analog scale scores improved significantly (70 [20]-45 [25] at 1 mo, P = 0.008). Pain Disability Questionnaire scores improved at 1 mo (100 [23]-77 [30], P = 0.009) in the KA group and at all time points in the HA group (102 [28]-74 [34] at 1 mo, P = 0.002; 74 [36] at 3 mos, P = 0.037; 79 at 6 mos [median = 52-99.5], P < 0.001). Medians and quartiles were used in statistical analysis when data did not pass normality. CONCLUSIONS: Patients with chronic low back pain suggestive of lumbar lumbar zygopophyseal joint arthropathy responded similarly to triamcinolone or hyaluronate injections. Synvisc-One group showed significant short- and long-term functional improvement and short-term pain improvement; KA group showed only significant short-term functional benefit and no significant short- or long-term pain improvement.

A comparison of the motivational factors between CrossFit participants and other resistance exercise modalities: a pilot study.

BACKGROUND: Understanding resistance exercise motives and participation is essential in increasing exercise adherence and reducing comorbidities. CrossFit is a fitness movement that has seen an explosive growth in popularity worldwide; however, little research has investigated the motivational factors within this "niche" resistance exercise environment. The aim of this study was to explore the motivational factors of CrossFit participants in comparison to other resistance exercise participants. METHODS: Using an independent-group design, quantitative data was collected using exercise motivations inventory-2 (EMI-2) questionnaire, for a total of 314 male and female participants (CrossFit: N.=68, group resistance exercise: N.=55, alone: N.=125, personal trainer: N.=66). RESULTS: The present study suggest that CrossFit participants were more likely to report higher levels of intrinsic motives, such as enjoyment, challenge and affiliation, whereas personal training clients reported higher values for health related motives such as positive health, ill-health avoidance and weight management. CONCLUSIONS: The findings suggest that the motivations for engaging in CrossFit may be similar to those seen in sport participation, and therefore may have an influence on facilitating long-term adherence in comparison with other resistance exercise modalities. This article also discusses health related motives as being extrinsic in nature but reflecting intrinsic characteristics, potentially also facilitating long term adherence. The present research helps develop further understanding of motivational variables within differing resistance exercise modalities.

The effects of muscle action, repetition duration, and loading strategies of a whole-body, progressive resistance training programme on muscular performance and body composition in trained males and females.

Research has produced equivocal results with regard to eccentric (ECC) only compared with traditional concentric/eccentric resistance training (RT). When considered in relation to load- and repetition duration-accentuated (ECC) training as well as the use of isokinetic and isoinertial training methods, there is a relative dearth of literature considering multi-joint, multi-exercise RT interventions. The present study considered 59 male and female participants randomly divided in to 3 sex counterbalanced groups; ECC only (ECC, n = 20), repetition duration-accentuated ECC (ECC-A, n = 20), and traditional (CON, n = 19) performing full-body, effort matched RT programmes for 2 days·week-1 for 10 weeks. Outcomes were muscular performance, including absolute muscular endurance and predicted 1-repetition maximum, in addition to body composition. No significant between-groups differences were identified for change in muscular performance measures for leg press or chest press exercises, or for body composition changes. Analyses revealed a significantly greater improvement for CON compared with ECC groups (p < 0.05) for change in absolute muscular endurance for the pull-down exercise. Effect sizes for muscular performance changes were moderate to large for all groups and exercises (0.75-2.00). The present study supports previous research that ECC-only training produces similar improvements in muscular performance to traditional training where intensity of effort is controlled. Data herein further supports the use of uncomplicated, low-volume RT to momentary failure as an efficacious method of improving muscular performance in trained persons.

The Effects of Breakdown Set Resistance Training on Muscular Performance and Body Composition in Young Men and Women.

Breakdown (BD) training has been advocated by multiple commercial and academic publications and authors, seemingly as a result of the acute hormonal and muscle activation responses it produces. However, there is a relative dearth of research that has empirically considered this advanced method of resistance training (RT) over a chronic intervention while appropriately controlling other RT variables. The present study considered 36 male and female participants divided into 3 groups: BD (n = 11), heavy-load breakdown (n = 14), and traditional (n = 11), performing full-body RT programs 2 times per week for 12 weeks. No significant between-group differences were identified for change in absolute muscular endurance for chest press, leg press, or pull-down exercises or for body composition changes. Effect sizes for absolute muscular endurance changes were large for all groups and exercises (0.86-2.74). The present study supports previous research that the use of advanced training techniques stimulates no greater muscular adaptations when compared with performing more simplified RT protocols to momentary muscular failure.