Pub Date : 2025-09-08DOI: 10.1249/mss.0000000000003852
Jelle Habay,Y Laurisa Arenales Arauz,Matthias Proost,Emilie Schampheleer,Elke Lathouwers,Kevin De Pauw,Nathalie Pattyn,Jeroen Van Cutsem,Bart Roelands
PURPOSEAlthough many studies have demonstrated that prolonged cognitive load can impair subsequent cognitive and physical performance, commonly described as mental fatigue, more recent findings suggest that the relationship is more nuanced. Moreover, significant heterogeneity between different smaller studies make it difficult to summarize definitive conclusions. The aim of the present study was to provide a more robust examination of the detrimental effects of sustained cognitive demands on cognitive and physical performance fatigability, using a large sample within a controlled environment.METHODS117 participants (57 ♀; 32 ± 9 y) were included in this randomized counterbalanced crossover experiment (NCT05576935), consisting of a familiarization, intervention (45 min individualized Stroop task) and control (45 min self-chosen documentary) session. Performance was evaluated using a 6-min GoNoGo task and a 20-min cycling time trial. Multiple secondary outcomes, such as rate of perceived exertion (RPE), feelings of fatigue and motivation, were incorporated to explore their relationship to possible behavioural effects.RESULTSThere was a significant worsening of GoNoGo reaction time between conditions (p < 0.001; ηp2 = 0.07). A trend towards significance was found regarding the negative influence of the Stroop task on time trial distance (p = 0.059; d = 0.20), which was linked to a significant decrease in cadence (p = 0.042; d = 0.22) in the intervention condition. Moreover, the feelings of physical fatigue (p < 0.001; ηp2 = 0.01), mental fatigue (p < 0.001; r = 0.37-0.47) and RPE (p = 0.002; ηp2 = 0.01) remained higher during the time trial in the intervention condition compared to the control condition.CONCLUSIONSIn the present study, prolonged cognitive effort impaired specific cognitive and physical performance outcomes, consistent with the characteristics of mental fatigue. Secondary outcomes show an important role for the feeling of fatigue in the determination of physical performance.
{"title":"Mental Fatigue Negatively Impacts Cognitive and Physical Performance Outcomes: A Large-Scale Randomized Crossover Trial.","authors":"Jelle Habay,Y Laurisa Arenales Arauz,Matthias Proost,Emilie Schampheleer,Elke Lathouwers,Kevin De Pauw,Nathalie Pattyn,Jeroen Van Cutsem,Bart Roelands","doi":"10.1249/mss.0000000000003852","DOIUrl":"https://doi.org/10.1249/mss.0000000000003852","url":null,"abstract":"PURPOSEAlthough many studies have demonstrated that prolonged cognitive load can impair subsequent cognitive and physical performance, commonly described as mental fatigue, more recent findings suggest that the relationship is more nuanced. Moreover, significant heterogeneity between different smaller studies make it difficult to summarize definitive conclusions. The aim of the present study was to provide a more robust examination of the detrimental effects of sustained cognitive demands on cognitive and physical performance fatigability, using a large sample within a controlled environment.METHODS117 participants (57 ♀; 32 ± 9 y) were included in this randomized counterbalanced crossover experiment (NCT05576935), consisting of a familiarization, intervention (45 min individualized Stroop task) and control (45 min self-chosen documentary) session. Performance was evaluated using a 6-min GoNoGo task and a 20-min cycling time trial. Multiple secondary outcomes, such as rate of perceived exertion (RPE), feelings of fatigue and motivation, were incorporated to explore their relationship to possible behavioural effects.RESULTSThere was a significant worsening of GoNoGo reaction time between conditions (p < 0.001; ηp2 = 0.07). A trend towards significance was found regarding the negative influence of the Stroop task on time trial distance (p = 0.059; d = 0.20), which was linked to a significant decrease in cadence (p = 0.042; d = 0.22) in the intervention condition. Moreover, the feelings of physical fatigue (p < 0.001; ηp2 = 0.01), mental fatigue (p < 0.001; r = 0.37-0.47) and RPE (p = 0.002; ηp2 = 0.01) remained higher during the time trial in the intervention condition compared to the control condition.CONCLUSIONSIn the present study, prolonged cognitive effort impaired specific cognitive and physical performance outcomes, consistent with the characteristics of mental fatigue. Secondary outcomes show an important role for the feeling of fatigue in the determination of physical performance.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145035769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BACKGROUNDOsteoarthritis is a leading cause of disability and is accompanied by pain, high medical expenditures, and poor quality of life. Adults with obesity develop osteoarthritis at twice the rate of normal weight adults, in part due to higher joint loading. Middle-aged adults have the highest prevalence of obesity among adult age groups. Physical activity is recommended for overall health benefits and can improve walking mechanics. Changes in bodyweight composition and distribution also influence biomechanical control of gait.PURPOSEThis analysis evaluated how daily physical activity level (PAL) is related to joint loading during gait in middle-aged adults with obesity, and the role of body composition on these relationships.METHODSTwenty-nine middle-aged (52.1 ± 8.1 years) adults with obesity (36.1 ± 3.6 kg/m2) walked over an instrumented walkway. Maximum vertical ground reaction force (max vGRF), total stance load (TL), and loading rate (LR) were calculated. Participants completed one week of at-home wrist-worn activity monitoring.RESULTSPAL was associated with max vGRF (ρ = -0.64,P < 0.001) and TL (ρ = -0.57,P = 0.001). Waist to hip ratio (WHR) and bodyfat percentage (BFP) independently mediated the relationships between PAL and joint loading variables explaining up to 36% and 31% of the variance in joint loading in multiple regression models, respectively.CONCLUSIONSMiddle-aged adults with higher PAL demonstrated smaller joint loading during gait. Relationships between joint loading and PAL were mediated by WHR and BFP. Promoting physical activity and tracking changes to body composition are important for reducing joint loading during walking even when weight loss is not considered.
{"title":"The Relationship Between Joint Loading and Physical Activity Level in Middle-Aged Adults with Obesity, and the Role of Body Composition.","authors":"Julie Rekant,Scott Rothenberger,Mark Redfern,Jennifer Brach,Theodore Huppert,April Chambers","doi":"10.1249/mss.0000000000003844","DOIUrl":"https://doi.org/10.1249/mss.0000000000003844","url":null,"abstract":"BACKGROUNDOsteoarthritis is a leading cause of disability and is accompanied by pain, high medical expenditures, and poor quality of life. Adults with obesity develop osteoarthritis at twice the rate of normal weight adults, in part due to higher joint loading. Middle-aged adults have the highest prevalence of obesity among adult age groups. Physical activity is recommended for overall health benefits and can improve walking mechanics. Changes in bodyweight composition and distribution also influence biomechanical control of gait.PURPOSEThis analysis evaluated how daily physical activity level (PAL) is related to joint loading during gait in middle-aged adults with obesity, and the role of body composition on these relationships.METHODSTwenty-nine middle-aged (52.1 ± 8.1 years) adults with obesity (36.1 ± 3.6 kg/m2) walked over an instrumented walkway. Maximum vertical ground reaction force (max vGRF), total stance load (TL), and loading rate (LR) were calculated. Participants completed one week of at-home wrist-worn activity monitoring.RESULTSPAL was associated with max vGRF (ρ = -0.64,P < 0.001) and TL (ρ = -0.57,P = 0.001). Waist to hip ratio (WHR) and bodyfat percentage (BFP) independently mediated the relationships between PAL and joint loading variables explaining up to 36% and 31% of the variance in joint loading in multiple regression models, respectively.CONCLUSIONSMiddle-aged adults with higher PAL demonstrated smaller joint loading during gait. Relationships between joint loading and PAL were mediated by WHR and BFP. Promoting physical activity and tracking changes to body composition are important for reducing joint loading during walking even when weight loss is not considered.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"161 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-03DOI: 10.1249/mss.0000000000003847
Daniel C Basile,Charles L Rice
INTRODUCTIONEccentric (ECC) contractions are uniquely characterized by higher maximal torque output compared to concentric or isometric actions. However, this advantage is accompanied by greater and more prolonged torque loss following fatiguing eccentric exercise compared with other modalities. Although muscle contractile responses to dynamic fatiguing contractions have been documented, the neural control of eccentric contractions - particularly at the level of individual motor units - remains poorly understood. The purpose was to evaluate motor unit discharge rate (MUDR) modulation during, and in recovery after a maximal effort eccentric fatiguing task.METHODSSingle motor unit activity was recorded with fine-wire electrodes inserted into the triceps brachii muscle. Participants completed an elbow extension protocol with subsequent recovery for 30 minutes, involving repetitive sets of 10 maximal repetitions until 50% torque loss relative to baseline maximal ECC torque.RESULTSMUDR declined substantially (>35%) from baseline to task failure (37.1 Hz vs. 23.1 Hz, p ≤ 0.001), and did not return to baseline values until 10 min of recovery (p = 0.597). However, both electrically stimulated twitch torque and maximal voluntary eccentric torque remained depressed at 30 min (p = 0.001), relative to baseline.CONCLUSIONSThis study provides a novel characterization of motor unit behavior during fatigue induced by maximal eccentric contractions, revealing a significant reduction consistent with prior evidence of impaired MUDR under other fatiguing tasks. Additionally, results indicate that prolonged torque depression (30 min post-task failure) following the eccentric fatiguing task is primarily attributable to peripheral muscle impairments, as MUDR recovered to baseline within ~10 min.
与同心或等距收缩相比，偏心（ECC）收缩具有更高的最大扭矩输出的独特特点。然而，与其他方式相比，这种优势伴随着疲劳偏心运动后更大更长的扭矩损失。尽管对动态疲劳收缩的肌肉收缩反应已有文献记载，但对偏心收缩的神经控制——特别是在单个运动单元的水平上——仍然知之甚少。目的是评估运动单元放电率（MUDR）调制期间，并在恢复后的最大努力偏心疲劳任务。方法采用细丝电极插入肱三头肌，记录单运动单元活动。参与者完成了肘关节伸展治疗方案，随后恢复30分钟，包括重复10次最大重复，直到相对于基线最大ECC扭矩损失50%。结果从基线到任务失败（37.1 Hz vs. 23.1 Hz, p≤0.001），smudr显著下降（>35%），直到恢复10分钟才恢复到基线值（p = 0.597）。然而，与基线相比，电刺激的抽搐扭矩和最大自主偏心扭矩在30分钟时仍然降低（p = 0.001）。结论：本研究为最大偏心收缩引起的疲劳中运动单元的行为提供了一种新的特征，揭示了在其他疲劳任务下MUDR受损的显著减少，这与先前的证据一致。此外，结果表明，偏心疲劳任务后长时间的扭矩下降（任务失败后30分钟）主要归因于外周肌肉损伤，因为MUDR在10分钟内恢复到基线。
{"title":"Motor Unit Discharge Rates during Maximal Fatiguing Eccentric Contractions and Recovery in the Human Elbow Extensors.","authors":"Daniel C Basile,Charles L Rice","doi":"10.1249/mss.0000000000003847","DOIUrl":"https://doi.org/10.1249/mss.0000000000003847","url":null,"abstract":"INTRODUCTIONEccentric (ECC) contractions are uniquely characterized by higher maximal torque output compared to concentric or isometric actions. However, this advantage is accompanied by greater and more prolonged torque loss following fatiguing eccentric exercise compared with other modalities. Although muscle contractile responses to dynamic fatiguing contractions have been documented, the neural control of eccentric contractions - particularly at the level of individual motor units - remains poorly understood. The purpose was to evaluate motor unit discharge rate (MUDR) modulation during, and in recovery after a maximal effort eccentric fatiguing task.METHODSSingle motor unit activity was recorded with fine-wire electrodes inserted into the triceps brachii muscle. Participants completed an elbow extension protocol with subsequent recovery for 30 minutes, involving repetitive sets of 10 maximal repetitions until 50% torque loss relative to baseline maximal ECC torque.RESULTSMUDR declined substantially (>35%) from baseline to task failure (37.1 Hz vs. 23.1 Hz, p ≤ 0.001), and did not return to baseline values until 10 min of recovery (p = 0.597). However, both electrically stimulated twitch torque and maximal voluntary eccentric torque remained depressed at 30 min (p = 0.001), relative to baseline.CONCLUSIONSThis study provides a novel characterization of motor unit behavior during fatigue induced by maximal eccentric contractions, revealing a significant reduction consistent with prior evidence of impaired MUDR under other fatiguing tasks. Additionally, results indicate that prolonged torque depression (30 min post-task failure) following the eccentric fatiguing task is primarily attributable to peripheral muscle impairments, as MUDR recovered to baseline within ~10 min.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BACKGROUNDWearable devices that measure energy expenditure are not designed for children. Therefore, we developed the PATCH (Platform for Accurate Tracking of Children's Health), an open-source device to measure children's energy expenditure using heartrate (HR) and acceleration. This study examines three models to estimate children's oxygen consumption using HR and acceleration compared to a criterion of indirect calorimetry.METHODSFifty-two children aged 3-8 yrs (mean age 6.4 ± 1.7, 42% female, 73% White) completed a semi-structured protocol ranging in intensity from inactive (e.g., using iPad) to vigorous (e.g., running). The PATCH was attached to the chest, and measured HR (photoplethysmography) and acceleration (3-axis accelerometer, ±16 g). The criterion (Cosmed K5) measured breath by breath oxygen uptake (VO2ml/kg/min). We used cross-sectional time series (CSTS) models, generalized additive mixed models (GAMM) and random forest (RF) to predict oxygen consumption from a combination of HR, acceleration and participant characteristics (biological sex, age, weight, height). We used 10-fold cross-validation, testing each fold and training on the rest, repeated for robustness. Model fit was assessed using mean bias, mean absolute error (MAE), mean absolute percent error (MAPE) and variance explained (R2). We reported out-of-sample R-squared values without subject-specific random effects to ensure broad applicability.RESULTSMean bias for CSTS, GAMM, and RF was -0.01, 0.01, and 0.08 ml/kg/min, respectively. MAE values were 1.54, 1.56, and 1.99 ml/kg/min; MAPE was 10% for CSTS and GAMM, and 13% for RF. The CSTS explained 86% (SD 5%) of variance, GAMM 86% (SD 5%), and RF 81% (SD 6%) in oxygen consumption.CONCLUSIONSCSTS, GAMM, and RF models provide similarly accurate estimates of children's oxygen consumption using the PATCH device compared to indirect calorimetry. Further validation in larger, free-living samples is needed.
{"title":"Initial Validation of the PATCH: an Open-Source Device Designed to Measure Energy Expenditure among Children Aged 3-8 Years.","authors":"Rahul Gosal,Glenn Weaver,Hannah Parker,Sarah Burkart,Jonas McAninch,Abbi Lane,Michal T Smith,Sydney Hill,Russ Pate,Mvs Chandrashekhar,Bridget Armstrong","doi":"10.1249/mss.0000000000003841","DOIUrl":"https://doi.org/10.1249/mss.0000000000003841","url":null,"abstract":"BACKGROUNDWearable devices that measure energy expenditure are not designed for children. Therefore, we developed the PATCH (Platform for Accurate Tracking of Children's Health), an open-source device to measure children's energy expenditure using heartrate (HR) and acceleration. This study examines three models to estimate children's oxygen consumption using HR and acceleration compared to a criterion of indirect calorimetry.METHODSFifty-two children aged 3-8 yrs (mean age 6.4 ± 1.7, 42% female, 73% White) completed a semi-structured protocol ranging in intensity from inactive (e.g., using iPad) to vigorous (e.g., running). The PATCH was attached to the chest, and measured HR (photoplethysmography) and acceleration (3-axis accelerometer, ±16 g). The criterion (Cosmed K5) measured breath by breath oxygen uptake (VO2ml/kg/min). We used cross-sectional time series (CSTS) models, generalized additive mixed models (GAMM) and random forest (RF) to predict oxygen consumption from a combination of HR, acceleration and participant characteristics (biological sex, age, weight, height). We used 10-fold cross-validation, testing each fold and training on the rest, repeated for robustness. Model fit was assessed using mean bias, mean absolute error (MAE), mean absolute percent error (MAPE) and variance explained (R2). We reported out-of-sample R-squared values without subject-specific random effects to ensure broad applicability.RESULTSMean bias for CSTS, GAMM, and RF was -0.01, 0.01, and 0.08 ml/kg/min, respectively. MAE values were 1.54, 1.56, and 1.99 ml/kg/min; MAPE was 10% for CSTS and GAMM, and 13% for RF. The CSTS explained 86% (SD 5%) of variance, GAMM 86% (SD 5%), and RF 81% (SD 6%) in oxygen consumption.CONCLUSIONSCSTS, GAMM, and RF models provide similarly accurate estimates of children's oxygen consumption using the PATCH device compared to indirect calorimetry. Further validation in larger, free-living samples is needed.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-03DOI: 10.1249/mss.0000000000003843
Charles E Matthews,Jeffrey Vallance,Jessica McNeil,Chad W Wagoner,Qinggang Wang,Leanne Dickau,Margaret L McNeely,S Nicole Culos-Reed,Lin Yang,Kerry S Courneya,Christine M Friedenreich
PURPOSEWearable sensors that track physical activity in daily life may offer insights that help healthcare providers optimize care plans for individuals with cancer. Therefore, we examined the links between lower health-related fitness and worse patient-reported health and various step-based metrics.METHODSThe Alberta Moving Beyond Breast Cancer Study enrolled 1,528 women recently diagnosed with breast cancer and measured health-related fitness and patient-reported health outcomes near diagnosis, and one year later. Step counts and intensity (cadence, peak steps) were measured by activPAL® over seven days at baseline. We estimated cross-sectional associations (odds ratios (OR)) at baseline, and prospective associations between low baseline stepping and low fitness and poorer health at one year, adjusting for age, demographics, height, weight, and cancer diagnosis/treatment.RESULTSAt baseline 1,408 breast cancer survivors (mean age 56 yrs; early stage (90%)) provided valid activPAL measures (mean 5.5 days of wear). Taking <5,000 steps/d (lower quintile) at baseline was associated with lower aerobic fitness, muscular strength and endurance, lower physical and mental quality of life, and greater fatigue and upper extremity disability at baseline and one year later. Taking <5,000 steps/d at baseline was associated with greater risk of moving from favorable to unfavorable categories of aerobic fitness (OR = 2.64), curl-ups (OR = 1.84), chest endurance (OR = 2.38), self-reported health (OR = 2.37), physical quality of life (OR = 2.13), and fatigue (OR = 1.81) one year later. Preferred cadence and peak stepping were inconsistently associated after adjustment for total steps.CONCLUSIONSAlthough our findings need to be replicated, they suggest that simple step counts measured near diagnosis could help healthcare providers assess the fitness and health status of women recently diagnosed with breast cancer and improve their survivorship care plans.
{"title":"Can Step-Based Metrics Predict Current and Future Health-Related Fitness and Patient-Reported Outcomes among Women Diagnosed with Breast Cancer?","authors":"Charles E Matthews,Jeffrey Vallance,Jessica McNeil,Chad W Wagoner,Qinggang Wang,Leanne Dickau,Margaret L McNeely,S Nicole Culos-Reed,Lin Yang,Kerry S Courneya,Christine M Friedenreich","doi":"10.1249/mss.0000000000003843","DOIUrl":"https://doi.org/10.1249/mss.0000000000003843","url":null,"abstract":"PURPOSEWearable sensors that track physical activity in daily life may offer insights that help healthcare providers optimize care plans for individuals with cancer. Therefore, we examined the links between lower health-related fitness and worse patient-reported health and various step-based metrics.METHODSThe Alberta Moving Beyond Breast Cancer Study enrolled 1,528 women recently diagnosed with breast cancer and measured health-related fitness and patient-reported health outcomes near diagnosis, and one year later. Step counts and intensity (cadence, peak steps) were measured by activPAL® over seven days at baseline. We estimated cross-sectional associations (odds ratios (OR)) at baseline, and prospective associations between low baseline stepping and low fitness and poorer health at one year, adjusting for age, demographics, height, weight, and cancer diagnosis/treatment.RESULTSAt baseline 1,408 breast cancer survivors (mean age 56 yrs; early stage (90%)) provided valid activPAL measures (mean 5.5 days of wear). Taking <5,000 steps/d (lower quintile) at baseline was associated with lower aerobic fitness, muscular strength and endurance, lower physical and mental quality of life, and greater fatigue and upper extremity disability at baseline and one year later. Taking <5,000 steps/d at baseline was associated with greater risk of moving from favorable to unfavorable categories of aerobic fitness (OR = 2.64), curl-ups (OR = 1.84), chest endurance (OR = 2.38), self-reported health (OR = 2.37), physical quality of life (OR = 2.13), and fatigue (OR = 1.81) one year later. Preferred cadence and peak stepping were inconsistently associated after adjustment for total steps.CONCLUSIONSAlthough our findings need to be replicated, they suggest that simple step counts measured near diagnosis could help healthcare providers assess the fitness and health status of women recently diagnosed with breast cancer and improve their survivorship care plans.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-03DOI: 10.1249/mss.0000000000003848
Francesco Bettariga,Dennis R Taaffe,Cristina Crespo-Garcia,Timothy D Clay,Mauro De Santi,Giulia Baldelli,Sanjeev Adhikari,Elin S Gray,Daniel A Galvão,Robert U Newton
PURPOSEReducing recurrence and mortality is crucial for breast cancer survivors. We investigated the effects of a 12-week resistance training (RT) vs high-intensity interval training (HIIT) program on myokines, cytokines secreted by skeletal muscle cells at rest in response to muscle contraction, and cancer cell inhibition.METHODSTwenty-eight survivors of breast cancer (age 55.5 ± 8.8 yr, body mass index 27.9 ± 5.1 kg/m2, time since diagnosis 31 ± 12.3 months) were randomly allocated to a 12-week supervised moderate to high intensity RT (n = 14) or HIIT (n = 14) program 3 days per week. Resting blood was collected before and post exercise program (at least 48 hours before the first and after the last exercise session) to measure serum levels of myokines (decorin, interleukin 6 [IL-6], secreted protein acidic and rich in cysteine [SPARC], and oncostatin M [OSM]) and triple negative MDA-MB-231 cell growth in vitro, using real time cellular analysis to determine growth rate.RESULTSExercise attendance was 85% for RT and 81% for HIIT. Serum levels of SPARC for RT and OSM for HIIT significantly (p < 0.05) increased (11 to 15%) after 12 weeks, with no significant differences between groups. MDA-MB-231 cell growth was significantly (p < 0.05) reduced for both RT and HIIT by 22% and 25%, respectively, with no significant difference between groups. Reductions in MDA-MB-231 cell growth in HIIT were associated with improvements in lean and fat mass.CONCLUSIONSA program of RT or HIIT can increase levels of myokines (an effect considered beneficial given their potential cancer-suppressive effects) and inhibit growth of MDA-MB-231 cells in survivors of breast cancer. In addition, development of the anti-tumor environment may be mediated by exercise-related changes in muscle strength and body composition.
{"title":"Effects of Resistance vs High Intensity Interval Training on Myokines and Cancer Cell Suppression in Breast Cancer Survivors: A Randomized Trial.","authors":"Francesco Bettariga,Dennis R Taaffe,Cristina Crespo-Garcia,Timothy D Clay,Mauro De Santi,Giulia Baldelli,Sanjeev Adhikari,Elin S Gray,Daniel A Galvão,Robert U Newton","doi":"10.1249/mss.0000000000003848","DOIUrl":"https://doi.org/10.1249/mss.0000000000003848","url":null,"abstract":"PURPOSEReducing recurrence and mortality is crucial for breast cancer survivors. We investigated the effects of a 12-week resistance training (RT) vs high-intensity interval training (HIIT) program on myokines, cytokines secreted by skeletal muscle cells at rest in response to muscle contraction, and cancer cell inhibition.METHODSTwenty-eight survivors of breast cancer (age 55.5 ± 8.8 yr, body mass index 27.9 ± 5.1 kg/m2, time since diagnosis 31 ± 12.3 months) were randomly allocated to a 12-week supervised moderate to high intensity RT (n = 14) or HIIT (n = 14) program 3 days per week. Resting blood was collected before and post exercise program (at least 48 hours before the first and after the last exercise session) to measure serum levels of myokines (decorin, interleukin 6 [IL-6], secreted protein acidic and rich in cysteine [SPARC], and oncostatin M [OSM]) and triple negative MDA-MB-231 cell growth in vitro, using real time cellular analysis to determine growth rate.RESULTSExercise attendance was 85% for RT and 81% for HIIT. Serum levels of SPARC for RT and OSM for HIIT significantly (p < 0.05) increased (11 to 15%) after 12 weeks, with no significant differences between groups. MDA-MB-231 cell growth was significantly (p < 0.05) reduced for both RT and HIIT by 22% and 25%, respectively, with no significant difference between groups. Reductions in MDA-MB-231 cell growth in HIIT were associated with improvements in lean and fat mass.CONCLUSIONSA program of RT or HIIT can increase levels of myokines (an effect considered beneficial given their potential cancer-suppressive effects) and inhibit growth of MDA-MB-231 cells in survivors of breast cancer. In addition, development of the anti-tumor environment may be mediated by exercise-related changes in muscle strength and body composition.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"155 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-03DOI: 10.1249/mss.0000000000003845
Jun Liu,Jing Gao,Qi Zou,Chen Li,Si-Chen Zhang,Rui-Jie Xu,Lin Shi,Ying Li,Xiao-Min Sun
PURPOSEWe have previously found that vitamin D and resistance exercise synergistically improve type 2 diabetes mellitus (T2DM)-related skeletal muscle atrophy. This study aims to investigate the impact of varying exercise intensity on synergistic effects of vitamin D and resistance exercise on their efficacy in improving type 2 diabetes mellitus (T2DM)-induced myopathy, and further elucidate the underlying mechanism.METHODSWe compared the effects of vitamin D combined with low-, moderate- and high-intensity resistance exercise on metabolic status and skeletal muscle function. Then, we explored the mechanism through lipidomic analysis in diabetic rats and verified in adults with T2DM.RESULTSWe found that combined intervention of vitamin D and medium-resistivity volume (MRV) exercise most effectively improved glucose metabolism and insulin sensitivity, increased muscular mass and strength, resulting to alleviated gastrocnemius muscle atrophy in diabetic rats. Vitamin D combined with MRV intervention increased expressions of vitamin D receptor and lysophosphatidylcholine acyltransferase 3, activated p38 MAPK and ERK1/2 signaling pathways, whereas suppressed inflammatory responses. Moreover, lipidomic analysis of gastrocnemius muscle indicated that lysophosphatidylcholine (LPC) 18:1 exhibited the most significant restoration after intervention. Notably, in adults with T2DM, reduced changes in plasma LPC 18:1 levels exhibited positive correlations with decreased appendicular skeletal muscle index, upper limb muscle mass, and thigh muscle mass.CONCLUSIONSOur findings suggested that vitamin D combined with MRV intervention has more pronounced effect on improving T2DM-related skeletal muscle atrophy. Additionally, LPC 18:1 may be a key target for regulating skeletal muscle function through p38 MAPK/ERK and inflammatory signaling pathways. These results provide novel insights for the prevention and treatment of T2DM-related skeletal muscle atrophy through lifestyle modifications.
{"title":"Role of LPC 18:1 in the Lipid Metabolic Response to Combined Vitamin D and Resistance Exercise for Protecting Diabetic Skeletal Muscle Function.","authors":"Jun Liu,Jing Gao,Qi Zou,Chen Li,Si-Chen Zhang,Rui-Jie Xu,Lin Shi,Ying Li,Xiao-Min Sun","doi":"10.1249/mss.0000000000003845","DOIUrl":"https://doi.org/10.1249/mss.0000000000003845","url":null,"abstract":"PURPOSEWe have previously found that vitamin D and resistance exercise synergistically improve type 2 diabetes mellitus (T2DM)-related skeletal muscle atrophy. This study aims to investigate the impact of varying exercise intensity on synergistic effects of vitamin D and resistance exercise on their efficacy in improving type 2 diabetes mellitus (T2DM)-induced myopathy, and further elucidate the underlying mechanism.METHODSWe compared the effects of vitamin D combined with low-, moderate- and high-intensity resistance exercise on metabolic status and skeletal muscle function. Then, we explored the mechanism through lipidomic analysis in diabetic rats and verified in adults with T2DM.RESULTSWe found that combined intervention of vitamin D and medium-resistivity volume (MRV) exercise most effectively improved glucose metabolism and insulin sensitivity, increased muscular mass and strength, resulting to alleviated gastrocnemius muscle atrophy in diabetic rats. Vitamin D combined with MRV intervention increased expressions of vitamin D receptor and lysophosphatidylcholine acyltransferase 3, activated p38 MAPK and ERK1/2 signaling pathways, whereas suppressed inflammatory responses. Moreover, lipidomic analysis of gastrocnemius muscle indicated that lysophosphatidylcholine (LPC) 18:1 exhibited the most significant restoration after intervention. Notably, in adults with T2DM, reduced changes in plasma LPC 18:1 levels exhibited positive correlations with decreased appendicular skeletal muscle index, upper limb muscle mass, and thigh muscle mass.CONCLUSIONSOur findings suggested that vitamin D combined with MRV intervention has more pronounced effect on improving T2DM-related skeletal muscle atrophy. Additionally, LPC 18:1 may be a key target for regulating skeletal muscle function through p38 MAPK/ERK and inflammatory signaling pathways. These results provide novel insights for the prevention and treatment of T2DM-related skeletal muscle atrophy through lifestyle modifications.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-02DOI: 10.1249/mss.0000000000003850
Wee Lun Foo,Catherine Hambly,Emma Tester,Panos Markakis,Jose L Areta,Graeme L Close,John R Speakman,James P Morton
PURPOSETo determine the total daily energy expenditure (TDEE) of male English Premier League (EPL) players during one-game week (1GW) and two-game week (2GW) microcycles, thereby informing carbohydrate (CHO) guidelines aligned to the increasing physical demands of the game.METHODSNine male players from an EPL club were assessed over a 15-day in-season period, including a 1GW followed by a 2GW. Measurements included TDEE (doubly labelled water, DLW), energy intake (remote food photography method, RFPM) and external physical loading.RESULTSAccumulative training and match duration was greater during 1GW (335 ± 22 min) compared to 2GW (307 ± 32 min, p = 0.013) whereas average speed was higher in 2GW (73 ± 7 m·min-1) versus 1GW (63 ± 4 m·min-1, p = 0.012). No differences were observed in accumulative total (25552 ± 3502 m vs 26360 ± 5462 m), high-speed running (1744 ± 536 m vs 1705 ± 752 m), or sprint distances (372 ± 150 m vs 324 ± 252 m) between 1GW and 2GW (all p < 0.05). Mean TDEE was 3551 ± 507 kcal·day-1, with no difference between 1GW (3554 ± 963 kcal·day-1) and 2GW (3467 ± 821 kcal·day-1, p = 0.781). Self-reported EI using RFPM (2975 ± 292 kcal·day-1) underestimated DLW derived EI estimates (3663 ± 665 kcal·day-1) by 724 ± 722 kcal·day-1 (18% error, p = 0.026).CONCLUSIONSTDEE in male EPL soccer players does not differ between 1GW and 2GW microcycles, likely due to the comparable external loads. Data provide further evidence that daily CHO intakes should likely range from 4-6 g.kg-1 on training days, increasing to 6-8 g.kg-1 for match day preparation, match day and recovery.
目的：确定男性英超球员在一场比赛周（1GW）和两场比赛周（2GW）微循环期间的每日总能量消耗（TDEE），从而为与比赛中不断增加的身体需求相一致的碳水化合物（CHO）指南提供信息。方法对来自英超俱乐部的9名男性球员进行了为期15天的赛季评估，包括1GW和2GW。测量包括TDEE（双标签水，DLW），能量摄入（远程食物摄影法，RFPM）和外部物理负荷。结果1GW组累计训练时间（335±22 min）高于2GW组（307±32 min, p = 0.013），平均速度（73±7 m·min-1）高于1GW组（63±4 m·min-1, p = 0.012）。1GW与2GW的累计跑程（25552±3502 m vs 26360±5462 m）、高速跑程（1744±536 m vs 1705±752 m）、冲刺距离（372±150 m vs 324±252 m）均无差异（p < 0.05）。平均TDEE为3551±507 kcal·day-1, 1GW（3554±963 kcal·day-1）与2GW（3467±821 kcal·day-1）无差异，p = 0.781。使用RFPM的自我报告EI（2975±292 kcal·day-1）比DLW获得的EI（3663±665 kcal·day-1）低724±722 kcal·day-1（误差18%，p = 0.026）。结论男性EPL足球运动员的stdee在1GW和2GW微循环之间没有差异，可能是由于相似的外负荷。数据提供了进一步的证据，每天的CHO摄入量应该从训练日的4-6 g.kg-1，增加到比赛日准备、比赛日和恢复的6-8 g.kg-1。
{"title":"Energy Expenditure of Male Soccer Players from an English Premier League Team Does Not Differ Between One-Game and Two-Game Per Week Microcycles.","authors":"Wee Lun Foo,Catherine Hambly,Emma Tester,Panos Markakis,Jose L Areta,Graeme L Close,John R Speakman,James P Morton","doi":"10.1249/mss.0000000000003850","DOIUrl":"https://doi.org/10.1249/mss.0000000000003850","url":null,"abstract":"PURPOSETo determine the total daily energy expenditure (TDEE) of male English Premier League (EPL) players during one-game week (1GW) and two-game week (2GW) microcycles, thereby informing carbohydrate (CHO) guidelines aligned to the increasing physical demands of the game.METHODSNine male players from an EPL club were assessed over a 15-day in-season period, including a 1GW followed by a 2GW. Measurements included TDEE (doubly labelled water, DLW), energy intake (remote food photography method, RFPM) and external physical loading.RESULTSAccumulative training and match duration was greater during 1GW (335 ± 22 min) compared to 2GW (307 ± 32 min, p = 0.013) whereas average speed was higher in 2GW (73 ± 7 m·min-1) versus 1GW (63 ± 4 m·min-1, p = 0.012). No differences were observed in accumulative total (25552 ± 3502 m vs 26360 ± 5462 m), high-speed running (1744 ± 536 m vs 1705 ± 752 m), or sprint distances (372 ± 150 m vs 324 ± 252 m) between 1GW and 2GW (all p < 0.05). Mean TDEE was 3551 ± 507 kcal·day-1, with no difference between 1GW (3554 ± 963 kcal·day-1) and 2GW (3467 ± 821 kcal·day-1, p = 0.781). Self-reported EI using RFPM (2975 ± 292 kcal·day-1) underestimated DLW derived EI estimates (3663 ± 665 kcal·day-1) by 724 ± 722 kcal·day-1 (18% error, p = 0.026).CONCLUSIONSTDEE in male EPL soccer players does not differ between 1GW and 2GW microcycles, likely due to the comparable external loads. Data provide further evidence that daily CHO intakes should likely range from 4-6 g.kg-1 on training days, increasing to 6-8 g.kg-1 for match day preparation, match day and recovery.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-01DOI: 10.1249/mss.0000000000003846
Julianna Mereu,Mitchell J Sammut,Theres Tijo,C W James Melling
INTRODUCTIONLimited research has examined the impact of training intensity on substrate utilization during acute exercise. Despite sex differences in the metabolic response to exercise few studies have examined females Purpose: This study compared the utilization of substrate during acute exercise following 8-weeks of low-intensity (LoT) and high-intensity (HiT) aerobic training (AT) in female rats. It was hypothesized that both training programs would result in increased fat oxidation during acute exercise, with HiT demonstrating a higher shift toward fat oxidation.METHODSThirty-six female rodents were divided into four groups: sedentary control (Control); acute exercise-only (AC); LoT; and HiT. The LoT and HiT groups performed progressive exercise up to an intensity of 21 and 36 m/min, respectively. After training, the trained and AC group performed an acute bout of 60-min exercise (30 m/min) and were sacrificed 30 minutes later.RESULTSLevels of epinephrine and PKA activity were significantly higher (P < 0.05) in both trained compared to the Controls. Both LoT and HiT exhibited higher muscle glycogen content in comparison to AC (P < 0.05), suggesting muscle glycogen sparing in the trained animals. Moreover, hepatic glycogen in the HiT animals was significantly higher than LoT suggesting that hepatic glycogenolysis was reduced. An increase in HSL activation in the HiT indicates a shift towards fat utilization during exercise and a directed role of PKA to a preferable activation and utilization of fat.CONCLUSIONSThese findings increase our understanding of various metabolic adaptations in response to different AT intensities in females.
{"title":"The Metabolic Adaptation to Exercise following Intensity-specific Aerobic Training in Female Rats.","authors":"Julianna Mereu,Mitchell J Sammut,Theres Tijo,C W James Melling","doi":"10.1249/mss.0000000000003846","DOIUrl":"https://doi.org/10.1249/mss.0000000000003846","url":null,"abstract":"INTRODUCTIONLimited research has examined the impact of training intensity on substrate utilization during acute exercise. Despite sex differences in the metabolic response to exercise few studies have examined females Purpose: This study compared the utilization of substrate during acute exercise following 8-weeks of low-intensity (LoT) and high-intensity (HiT) aerobic training (AT) in female rats. It was hypothesized that both training programs would result in increased fat oxidation during acute exercise, with HiT demonstrating a higher shift toward fat oxidation.METHODSThirty-six female rodents were divided into four groups: sedentary control (Control); acute exercise-only (AC); LoT; and HiT. The LoT and HiT groups performed progressive exercise up to an intensity of 21 and 36 m/min, respectively. After training, the trained and AC group performed an acute bout of 60-min exercise (30 m/min) and were sacrificed 30 minutes later.RESULTSLevels of epinephrine and PKA activity were significantly higher (P < 0.05) in both trained compared to the Controls. Both LoT and HiT exhibited higher muscle glycogen content in comparison to AC (P < 0.05), suggesting muscle glycogen sparing in the trained animals. Moreover, hepatic glycogen in the HiT animals was significantly higher than LoT suggesting that hepatic glycogenolysis was reduced. An increase in HSL activation in the HiT indicates a shift towards fat utilization during exercise and a directed role of PKA to a preferable activation and utilization of fat.CONCLUSIONSThese findings increase our understanding of various metabolic adaptations in response to different AT intensities in females.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-01DOI: 10.1249/mss.0000000000003838
Marie Besson,Bruno Pereira,Fabrice Rannou
INTRODUCTIONA hyperkinetic circulatory response has been described in some metabolic myopathies, a heterogeneous group of inborn errors of intermediary metabolism that interfere with the generation of ATP in skeletal muscle. However, an accurate picture of the cardiovascular response to exercise in the various metabolic myopathies remains elusive.MATERIAL AND METHODSWe therefore sought to systematically review the literature by searching the PubMed/MEDLINE and Embase databases. A meta-analysis was performed from observational studies that evaluated the cardiac output (Q), oxygen arterio-venous difference (avDO2), relationship between Q increase and VO2 increase (∆Q/∆VO2), and peak oxygen uptake (VO2peak) during a cardiopulmonary exercise testing in patients with metabolic myopathies. A random-effects meta-analysis model was then applied.RESULTSFrom an initial 13276 literature records, we identified 31 studies fulfilling the inclusion criteria. Compared to healthy age- and sex-matched controls, peak exercise Q is lower in respiratory chain deficiencies (RCD) [standardized mean difference (SMD, -0.63; 95% confidence interval (CI) -1.18, -0.08)] and glycolysis defects (GLY, myophosphorylase defect-McArdle disease, and phosphofructokinase defect-Tarui disease; SMD, -0.76; 95%CI, -1.17, -0.36)], peak exercise avDO2 is lower in RCD (SMD, -2.28; 95%CI, -3.19, -1.36) and GLY (SMD, -4.41; 95%CI, -5.81, -3.02), ∆Q/∆VO2 is higher in RCD (SMD, 1.70; 95%CI, 0.91, 2.48) and GLY (SMD, 3.05; 95%CI, 1.94, 4.16). Data are limited in lipid oxidation defects, with only two studies showing no difference in the aforementioned variables compared to healthy control subjects.Discussion/ConclusionsAlthough exercise responses were similar between GLY and RCD groups, greater heterogeneity in RCD suggests variable pathophysiology and underscores the need for standardized studies across metabolic myopathies.
{"title":"The Hyperkinetic Circulatory Response during Exercise in Metabolic Myopathies: A Peculiar Model of Integrated Biology.","authors":"Marie Besson,Bruno Pereira,Fabrice Rannou","doi":"10.1249/mss.0000000000003838","DOIUrl":"https://doi.org/10.1249/mss.0000000000003838","url":null,"abstract":"INTRODUCTIONA hyperkinetic circulatory response has been described in some metabolic myopathies, a heterogeneous group of inborn errors of intermediary metabolism that interfere with the generation of ATP in skeletal muscle. However, an accurate picture of the cardiovascular response to exercise in the various metabolic myopathies remains elusive.MATERIAL AND METHODSWe therefore sought to systematically review the literature by searching the PubMed/MEDLINE and Embase databases. A meta-analysis was performed from observational studies that evaluated the cardiac output (Q), oxygen arterio-venous difference (avDO2), relationship between Q increase and VO2 increase (∆Q/∆VO2), and peak oxygen uptake (VO2peak) during a cardiopulmonary exercise testing in patients with metabolic myopathies. A random-effects meta-analysis model was then applied.RESULTSFrom an initial 13276 literature records, we identified 31 studies fulfilling the inclusion criteria. Compared to healthy age- and sex-matched controls, peak exercise Q is lower in respiratory chain deficiencies (RCD) [standardized mean difference (SMD, -0.63; 95% confidence interval (CI) -1.18, -0.08)] and glycolysis defects (GLY, myophosphorylase defect-McArdle disease, and phosphofructokinase defect-Tarui disease; SMD, -0.76; 95%CI, -1.17, -0.36)], peak exercise avDO2 is lower in RCD (SMD, -2.28; 95%CI, -3.19, -1.36) and GLY (SMD, -4.41; 95%CI, -5.81, -3.02), ∆Q/∆VO2 is higher in RCD (SMD, 1.70; 95%CI, 0.91, 2.48) and GLY (SMD, 3.05; 95%CI, 1.94, 4.16). Data are limited in lipid oxidation defects, with only two studies showing no difference in the aforementioned variables compared to healthy control subjects.Discussion/ConclusionsAlthough exercise responses were similar between GLY and RCD groups, greater heterogeneity in RCD suggests variable pathophysiology and underscores the need for standardized studies across metabolic myopathies.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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