Medicine and Science in Sports and Exercise最新文献

{"title":"Factors Associated with Fatigue in COVID-19 ICU Survivors.","authors":"Djahid Kennouche, Clément Foschia, Callum G Brownstein, Thomas Lapole, Diana Rimaud, Nicolas Royer, Franck LE Mat, Guillaume Thiery, Vincent Gauthier, Pascal Giraux, Lydia Oujamaa, Marine Sorg, Samuel Verges, Stéphane Doutreleau, Mathieu Marillier, Mélanie Prudent, Laurent Bitker, Léonard Féasson, Laurent Gergelé, Emeric Stauffer, Céline Guichon, Julien Gondin, Jérôme Morel, Guillaume Y Millet","doi":"10.1249/MSS.0000000000003455","DOIUrl":"10.1249/MSS.0000000000003455","url":null,"abstract":"<p><strong>Purpose: </strong>Approximately 30% of people infected with COVID-19 require hospitalization, and 20% of them are admitted to an intensive care unit (ICU). Most of these patients experience symptoms of fatigue weeks post-ICU, so understanding the factors associated with fatigue in this population is crucial.</p><p><strong>Methods: </strong>Fifty-nine patients (38-78 yr) hospitalized in ICU for COVID-19 infection for 32 (6-80) d, including 23 (3-57) d of mechanical ventilation, visited the laboratory on two separate occasions. The first visit occurred 52 ± 15 d after discharge and was dedicated to questionnaires, blood sampling, and cardiopulmonary exercise testing, whereas measurements of the knee extensors neuromuscular function and performance fatigability were performed in the second visit 7 ± 2 d later.</p><p><strong>Results: </strong>Using the FACIT-F questionnaire, 56% of patients were classified as fatigued. Fatigued patients had worse lung function score than non-fatigued (i.e., 2.9 ± 0.8 L vs 3.6 ± 0.8 L; 2.4 ± 0.7 L vs 3.0 ± 0.7 L for forced vital capacity and forced expiratory volume in 1 s, respectively), and forced vital capacity was identified as a predictor of being fatigued. Maximal voluntary activation was lower in fatigued patients than non-fatigued patients (82% ± 14% vs 91% ± 3%) and was the only neuromuscular variable that discriminated between fatigued and non-fatigued patients. Patient-reported outcomes also showed differences between fatigued and non-fatigued patients for sleep, physical activity, depression, and quality of life ( P < 0.05).</p><p><strong>Conclusions: </strong>COVID-19 survivors showed altered respiratory function 4 to 8 wk after discharge, which was further deteriorated in fatigued patients. Fatigue was also associated with lower voluntary activation and patient-reported impairments (i.e., sleep satisfaction, quality of life, or depressive state). The present study reinforces the importance of exercise intervention and rehabilitation to counteract cardiorespiratory and neuromuscular impairments of COVID-19 patients admitted in ICU, especially individuals experiencing fatigue.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":"1563-1573"},"PeriodicalIF":4.1,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140921285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urinary Proteomic Biomarkers of Trabecular Bone Volume Change during Army Basic Combat Training.","authors":"Shawn D Flanagan, Juliana R Hougland, Xuemei Zeng, Pamela S Cantrell, Mai Sun, Jackie Jones-Laughner, Maria C Canino, Julie M Hughes, Stephen A Foulis, Kathryn M Taylor, Leila A Walker, Katelyn I Guerriere, Adam J Sterczala, Chris Connaboy, Meaghan E Beckner, Ronald W Matheny, Bradley C Nindl","doi":"10.1249/MSS.0000000000003464","DOIUrl":"10.1249/MSS.0000000000003464","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of this study is to optimize a dMS-based urinary proteomic technique and evaluate the relationship between urinary proteome content and adaptive changes in bone microarchitecture during BCT.</p><p><strong>Methods: </strong>Urinary proteomes were analyzed with an optimized dMS technique in two groups of 13 recruits ( N = 26) at the beginning (Pre) and end (Post) of BCT. Matched by age (21 ± 4 yr), sex (16 W), and baseline tibial trabecular bone volume fractions (Tb.BV/TV), these groups were distinguished by the most substantial (High) and minimal (Low) improvements in Tb.BV/TV. Differential protein expression was analyzed with mixed permutation ANOVA and false discovery proportion-based adjustment for multiple comparisons.</p><p><strong>Results: </strong>Tibial Tb.BV/TV increased from pre- to post-BCT in High (3.30 ± 1.64%, P < 0.0001) but not Low (-0.35 ± 1.25%, P = 0.4707). The optimized dMS technique identified 10,431 peptides from 1368 protein groups that represented 165 integrative biological processes. Seventy-four urinary proteins changed from pre- to post-BCT ( P = 0.0019), and neutrophil-mediated immunity was the most prominent ontology. Two proteins (immunoglobulin heavy constant gamma 4 and C-type lectin domain family 4 member G) differed from pre- to post-BCT in High and Low ( P = 0.0006).</p><p><strong>Conclusions: </strong>The dMS technique can identify more than 1000 urinary proteins. At least 74 proteins are responsive to BCT, and other principally immune system-related proteins show differential expression patterns that coincide with adaptive bone formation.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":"1644-1654"},"PeriodicalIF":4.1,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140958446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fasciotomy and Occupational Separation among US Service Members with Lower Extremity Chronic Exertional Compartment Syndrome.","authors":"D Alan Nelson, Josh B Kazman, Kenneth Nelson, Daniel B Edgeworth, Michael F Lindow, Peter Emanuele, Daniel R Clifton, Y Sammy Choi, Donald Shell, Patricia A Deuster","doi":"10.1249/MSS.0000000000003471","DOIUrl":"10.1249/MSS.0000000000003471","url":null,"abstract":"<p><strong>Purpose: </strong>Lower extremity chronic exertional compartment syndrome (LE-CECS) can limit rigorous physical activity, particularly in the US military, and fasciotomy is a potential treatment. Associations between LE-CECS, fasciotomy, and occupational outcomes appear understudied. We studied active-duty US service members to identify whether LE-CECS diagnoses and fasciotomy for LE-CECS predict military service separation.</p><p><strong>Methods: </strong>We conducted a retrospective cohort study of 1,103,417 individuals who entered service during 2011 to 2017. Distributions of separation statuses and independent variables were tabulated, and sex-specific multivariable regression models were computed for separation outcomes.</p><p><strong>Results: </strong>LE-CECS was associated with a 474% medical service separation risk in men (95% confidence interval (CI) for adjusted risk ratio: 5.21 to 6.33) and a 282% increase in women (CI: 2.99 to 4.88). Among 1947 patients with LE-CECS, men saw a 57% nonmedical separation risk increase (CI: 1.27 to 1.93) and women had a 119% increase (CI: 1.10 to 4.35) when anterior and/or lateral compartment procedures occurred. Men with LE-CECS and any posterior procedures saw a 47% nonmedical separation risk increase (CI: 1.17 to 1.86). Men with anterior and/or lateral procedures and any posterior procedures experienced 36% (CI: 1.09 to 1.71) and 78% (CI: 1.40 to 2.26) medical separation risk increases, respectively. No statistically significant risk increases for the outcomes were otherwise seen for women.</p><p><strong>Conclusions: </strong>LE-CECS was associated with increased military service discharge risks. Among the affected patients, positive effects on career longevity were not seen in association with fasciotomy. However, fasciotomy could simply serve as a marker of the most refractory cases that are least likely to continue service. More study is needed to clarify causal pathways and identify patients who may derive career benefits from surgical treatment.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":"56 9","pages":"1685-1693"},"PeriodicalIF":4.1,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141982695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evidence for Simultaneous Muscle Atrophy and Hypertrophy in Response to Resistance Training in Humans.","authors":"Kim VAN Vossel, Julie Hardeel, Thibaux VAN DER Stede, Tom Cools, Jonas Vandecauter, Lynn Vanhaecke, Jan Boone, Silvia Salinas Blemker, Eline Lievens, Wim Derave","doi":"10.1249/MSS.0000000000003475","DOIUrl":"10.1249/MSS.0000000000003475","url":null,"abstract":"<p><strong>Purpose: </strong>Human skeletal muscle has the profound ability to hypertrophy in response to resistance training (RT). However, this has a high energy and protein cost and is presumably mainly restricted to recruited muscles. It remains largely unknown what happens with nonrecruited muscles during RT. This study investigated the volume changes of 17 recruited and 13 nonrecruited muscles during a 10-wk single-joint RT program targeting upper arm and upper leg musculature.</p><p><strong>Methods: </strong>Muscle volume changes were measured by manual or automatic 3D segmentation in 21 RT novices. Subjects ate ad libitum during the study and energy and protein intake were assessed by self-reported diaries.</p><p><strong>Results: </strong>Posttraining, all recruited muscles increased in volume (range: +2.2% to +17.7%, P < 0.05), whereas the nonrecruited adductor magnus (mean: -1.5% ± 3.1%, P = 0.038) and soleus (-2.4% ± 2.3%, P = 0.0004) decreased in volume. Net muscle growth ( r = 0.453, P = 0.045) and changes in adductor magnus volume ( r = 0.450, P = 0.047) were positively associated with protein intake. Changes in total nonrecruited muscle volume ( r = 0.469, P = 0.037), adductor magnus ( r = 0.640, P = 0.002), adductor longus ( r = 0.465, P = 0.039), and soleus muscle volume ( r = 0.481, P = 0.032) were positively related to energy intake. When subjects were divided into a HIGH or LOW energy intake group, overall nonrecruited muscle volume (-1.7% ± 2.0%), adductor longus (-5.6% ± 3.7%), adductor magnus (-2.8% ± 2.4%), and soleus volume (-3.7% ± 1.8%) decreased significantly ( P < 0.05) in the LOW but not the HIGH group.</p><p><strong>Conclusions: </strong>To our knowledge, this is the first study documenting that some nonrecruited muscles significantly atrophy during a period of RT. Our data therefore suggest muscle mass reallocation, that is, that hypertrophy in recruited muscles takes place at the expense of atrophy in nonrecruited muscles, especially when energy and protein availability are limited.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":"1634-1643"},"PeriodicalIF":4.1,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140851953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chronic Use of Antihypertensive Medications and Peak Exercise Blood Pressure in Adult Men and Women from the BALL ST Cohort.","authors":"Emily Idzik, Mary T Imboden, James E Peterman, Mitchell H Whaley, Leonard A Kaminsky, Bradley S Fleenor, Matthew P Harber","doi":"10.1249/MSS.0000000000003476","DOIUrl":"10.1249/MSS.0000000000003476","url":null,"abstract":"<p><strong>Purpose: </strong>To determine if individuals chronically (>1 yr) prescribed antihypertensive medications have a normal BP response to peak exercise compared with unmedicated individuals.</p><p><strong>Methods: </strong>Participants included 2555 adults from the Ball State Adult Fitness Longitudinal Lifestyle STudy cohort who performed a peak treadmill exercise test. Participants were divided into groups by sex and antihypertensive medication status. Individuals prescribed antihypertensive medications for >1 yr were included. Exaggerated and blunted SBP within each group was categorized using the Fitness Registry and the Importance of Exercise: A National Database (FRIEND) and absolute criteria as noted by the American Heart Association.</p><p><strong>Results: </strong>The unmedicated group had a greater prevalence ( P < 0.05) of blunted SBP responses, whereas the medicated group had a higher prevalence ( P < 0.05) of exaggerated SBP responses using both the FRIEND and absolute criteria. Peak SBP was higher ( P < 0.01) in medicated compared with unmedicated participants in the overall cohort when controlling for age and sex, but not after controlling for resting SBP ( P = 0.613), risk factors ( P = 0.104), or cardiorespiratory fitness ( P = 0.191). When men and women were assessed independently, peak SBP remained higher in the medicated women after controlling for age and resting SBP ( P = 0.039), but not for men ( P = 0.311). Individuals on beta-blockers had a higher peak SBP even after controlling for age, sex, risk factors, and cardiorespiratory fitness ( P = 0.022).</p><p><strong>Conclusions: </strong>Individuals on antihypertensive medications have a higher peak SBP response to exercise. Given the prognostic value of exaggerated peak SBP, control of exercise BP should be considered in routine BP assessment and in the treatment of hypertension.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":"1694-1700"},"PeriodicalIF":4.1,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141071532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Significance of Body Surface Area to Mass Ratio for Thermal Responses to a Standardized Exercise-Heat Stress Test.","authors":"Inbal Akavian, Yoram Epstein, Alexandra Rabotin, Shiraz Peretz, Nisha Charkoudian, Itay Ketko","doi":"10.1249/MSS.0000000000003545","DOIUrl":"https://doi.org/10.1249/MSS.0000000000003545","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the significance of body surface area-to-mass ratio (BSA/mass) on the heat-tolerance test (HTT) results. We hypothesized that individuals defined as heat tolerant (HT) would have on average higher BSA/mass compared to heat intolerant (HI) individuals.</p><p><strong>Methods: </strong>A retrospective reanalysis of the HTT results of 517 soldiers (age: 18-38 yrs., M/F: 96/4%), who were tested by the Israel Defense Forces (IDF) HTT protocol. The criterion for heat tolerance in the current analysis was a rectal temperature (Tre) plateau during the second hour of the test. A logistic regression analysis to evaluate the predictive power of BSA/mass for heat intolerance was performed; the spline model was applied to show the odds for heat intolerance across BSA/mass.</p><p><strong>Results: </strong>In men BSA/mass of HI individuals was lower than HT individuals (248 ± 19 vs. 262 ± 18 cm2/kg, p < 0.01, d = 0.76). In women a similar trend was noted but with no statistical significance between HT and HI groups. The odd ratio for heat intolerance for every unit increase in BSA/mass was 0.97 (CI 95% 0.95-0.99). The spline model plateaued above BSA/mass of 270 cm2/kg.</p><p><strong>Conclusions: </strong>The results imply that body-core temperature responses to a standard exercise-heat stress (fixed external work rate and climatic conditions) are influenced by BSA/mass. More specifically, lack of a steady state in Tre (indicating heat intolerance) was more likely to occur with every unit decrease in BSA/mass. These findings contribute to a better understanding of the role of body anthropometry in the response to a standard exercise-heat task that might have an implication on clinical decision-making about return to duty/play of soldiers, athletes and others who deemed to be identified as HI.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142109226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electromyography of Sedentary Behavior: Identifying Potential for Cardiometabolic Risk Reduction.","authors":"Suvi Lamberg, Christian J Brakenridge, David W Dunstan, Taija Finni, Genevieve N Healy, Neville Owen, Arto J Pesola","doi":"10.1249/MSS.0000000000003544","DOIUrl":"https://doi.org/10.1249/MSS.0000000000003544","url":null,"abstract":"<p><strong>Introduction: </strong>Muscle activation during interruptions to prolonged sedentary time is a hypothesized mechanism underlying observed cardiometabolic benefits. We examined associations of quadriceps and hamstring muscle activity patterns with cardiometabolic risk markers and how these patterns varied between different sitting-interruption countermeasures.</p><p><strong>Methods: </strong>Electromyographic (EMG) data (shorts) were gathered for 1 to 2 days from healthy adults in a free-living study (n = 172, age 40.9 ± 12.9, BMI 23.6 ± 1.3) and a laboratory-based study (n = 12, age 47.0 ± 7.7, BMI 30.0 ± 4.7). Patterns examined were average EMG (aEMG ;%EMGMVC); EMG activity duration (% above signal baseline 3 μV); and usual (weighted medians) EMG activity bout amplitude (%EMGMVC) and duration (s). In the free-living study, these were regressed against risk markers (waist; fat percentage; fasting plasma glucose [FPG];total cholesterol; HDL;LDL; triglycerides); in the laboratory study, EMG patterns for the muscle groups were compared between sitting and the active countermeasures.</p><p><strong>Results: </strong>In the free-living study, lower extremity muscles displayed minimal overall activity, with hamstrings and quadriceps using only 2.6% and 2.0% of their capacity (%EMGMVC), respectively, and being active for 30% and 25% of the time. Higher hamstring aEMG and EMG activity duration were beneficially associated with waist, HDL and fat percentage (duration only) and a longer quadriceps usual EMG activity bout duration was beneficially associated with FPG. In the laboratory study, compared with prolonged sitting, active seated or upright active-interruption countermeasures modified these EMG patterns; brief (6 min) walking and simple resistance activities (SRA) were more beneficial than was a bout of standing (30 min) with the SRAs being the only intervention that matched daily aEMG levels.</p><p><strong>Conclusions: </strong>Upright and physically active interruptions to sitting appear to be required to increase the typically low muscle engagement observed in free-living contexts, promoting muscle activity patterns that may help ameliorate cardiometabolic risk.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142109225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resolving Differences between MLSS and CP by Considering Rates of Change of Blood Lactate during Endurance Exercise.","authors":"Ozgur Ozkaya, Hakan As, Arda Peker, Mark Burnley, Andrew M Jones","doi":"10.1249/MSS.0000000000003548","DOIUrl":"https://doi.org/10.1249/MSS.0000000000003548","url":null,"abstract":"<p><strong>Purpose: </strong>To develop a new method that more closely represents the heavy-to-severe exercise domain boundary by evaluating the rates of blood lactate accumulation during the constant power output exercise bouts that are employed in the assessment of the maximal lactate steady state (MLSS).</p><p><strong>Methods: </strong>Eight well-trained male cyclists completed five exercise tests of up to 30 min for determination of the traditional MLSS (MLSSTRAD) and a further four maximal tests for determination of critical power (CP). The rates of change of blood [lactate] between 10 min and the end of exercise in the MLSS tests were plotted against the corresponding power outputs and a two-segment linear regression model was used to identify individualised breakpoints in lactate accumulation vs. power output (MLSSMOD).</p><p><strong>Results: </strong>MLSSMOD was significantly higher than MLSSTRAD (297 ± 41 vs. 278 ± 41 W; P < 0.001) but was not significantly different from CP (297 ± 41 W; P > 0.05); MLSSMOD and CP were closely aligned (r: 0.97; Bias: -0.52 W; SEE: 10 W; Limits of Agreement: -20 to 19 W). The rates of change of both blood [lactate] and V̇O2 were significantly greater, and exercise intolerance occurred before 30 min, at a power output slightly above MLSSMOD.</p><p><strong>Conclusions: </strong>A novel method for evaluating blood lactate kinetics during a traditional MLSS protocol produces a modified MLSS that is not different from CP and better represents the heavy-to-severe exercise domain boundary.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142073145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Consuming Whey Protein with Added Essential Amino Acids, not Carbohydrate, Maintains Post-Exercise Anabolism while Underfed.","authors":"Jess A Gwin, David D Church, Jillian T Allen, Marques A Wilson, Christopher T Carrigan, Nancy E Murphy, Alyssa N Varanoske, Lee M Margolis, Robert R Wolfe, Arny A Ferrando, Stefan M Pasiakos","doi":"10.1249/MSS.0000000000003541","DOIUrl":"10.1249/MSS.0000000000003541","url":null,"abstract":"<p><strong>Purpose: </strong>Energy deficiency decreases muscle protein synthesis (MPS), possibly due to greater whole-body essential amino acid (EAA) requirements and reliance on energy stores. Whether energy deficit-induced anabolic resistance is overcome with non-nitrogenous supplemental energy or if increased energy as EAA is needed is unclear. We tested the effects of energy as EAA or carbohydrate, combined with an EAA-enriched whey protein, on post-exercise MPS (%/h) and whole-body protein turnover (g protein/240 min).</p><p><strong>Methods: </strong>17 adults (mean ± SD; age: 26 ± 6 y, BMI: 25 ± 3 kg/m 2 ) completed a randomized, parallel study including two 5-d energy conditions (BAL, energy balance; DEF, -30 ± 3% energy requirements) separated by ≥7 d. Volunteers consumed EAA-enriched whey with added EAA (+EAA; 304 kcal, 56 g protein, 48 g EAA, 17 g carbohydrate, 2 g fat; n = 8) or added carbohydrate (+CHO; 311 kcal, 34 g protein, 24 g EAA, 40 g carbohydrate, 2 g fat; n = 9) following exercise. MPS and whole-body protein synthesis (PS), breakdown (PB), and net balance (NET; PS-PB) were estimated postexercise with isotope kinetics.</p><p><strong>Results: </strong>MPS rates were greater in +EAA (0.083 ± 0.02) than +CHO (0.059 ± 0.01; P = 0.015) during DEF, but similar during BAL ( P = 0.45) and across energy conditions within treatments ( P = 0.056). PS rates were greater for +EAA (BAL, 117.9 ± 16.5; DEF, 110.3 ± 14.8) than +CHO (BAL, 81.6 ± 8.0; DEF, 83.8 ± 5.9 g protein/240 min; both P < 0.001), and greater during BAL than DEF in +EAA ( P = 0.045). PB rates were less in +EAA (8.0 ± 16.5) than +CHO (37.8 ± 7.6 g protein/240 min; P < 0.001), and NET was greater in +EAA (106.1 ± 6.3) than +CHO (44.8 ± 8.5 g protein/240 min; P < 0.001).</p><p><strong>Conclusions: </strong>These data suggest that supplementing EAA-enriched whey protein with more energy as EAA, not carbohydrate, maintains postexercise MPS during energy deficit at rates comparable to those observed during energy balance.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142004582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determining Individualized Foot Progression Angle for Reduction of Knee Medial Compartment Loading During Stepping.","authors":"Raziyeh Baghi, Wei Yin, Ahmed Ramadan, Subham Badhyal, Giovanni Oppizzi, Dali Xu, Peter Bowman, Frank Henn, Li-Qun Zhang","doi":"10.1249/MSS.0000000000003531","DOIUrl":"https://doi.org/10.1249/MSS.0000000000003531","url":null,"abstract":"<p><strong>Purpose: </strong>Modifying foot progression angle (FPA), the angle between the line from the heel to the second metatarsal head and the line of progression, can reduce peak knee adduction moment (pKAM). However, determining the optimal FPA that minimizes pKAM without inducing unnatural walking patterns can be challenging. This study investigated the FPA-pKAM relationship using a robotic stepping trainer to assess the feasibility of determining the optimal FPA based on this relationship. Additionally, it examined knee moments during stepping with three different FPAs, as stepping is a recommended exercise for knee osteoarthritis (KOA) rehabilitation.</p><p><strong>Methods: </strong>Twenty-six asymptomatic individuals stepped on a robotic stepping trainer, which measured 6-axis footplate-reaction forces/torques and three-dimensional (3-D) ankle kinematics to determine external knee moments. The robot rotated the footplates slowly (~0.5 deg/sec) between 10°-toe-out and 10°-toe-in while participants stepped continuously, unaware of the footplate rotations. The slope of pKAM-FPA relationship during continuous stepping was determined. Peak 3-D knee moments were compared between the 10°-toe-in, 0°-FPA, and 10°-toe-out FPAs with repeated-measure ANOVA. Multiple linear regression determined the covariates that predicted pKAM during stepping.</p><p><strong>Results: </strong>Eighteen participants had lower pKAM and KAM impulse with 10°-toe-in than 10°-toe-out (p < 0.001) and 0°-FPA (p < 0.001 and p = 0.008, respectively) (called toe-in responders). Conversely, eight participants reduced pKAM and KAM impulse with 10°-toe-out compared to 0°-FPA (p < 0.001, p = 0.017) and 10°-toe-in (p = 0.026, p = 0.004) (called toe-out responders). A linear pKAM-FPA relationship was determined for each individual, and its slope (the pKAM rate with FPA) was positive for toe-in responders (p < 0.01) and negative for toe-out responders (p = 0.02). Regression analysis revealed that smaller pKAM with toe-in in toe-in responders was explained by increased tibia medial tilt, tibia internal rotation, footplate-reaction lateral force, footplate-reaction anterior force, and decreased footplate-reaction internal rotation torque.</p><p><strong>Conclusions: </strong>Individuals may exhibit different responses to FPA modification during stepping. The slope and intercept of the linear pKAM-FPA relationship can be determined for individual subjects. This allows for a targeted pKAM reduction through guided FPA positioning and potentially offers subject-specific precision KOA rehabilitation.</p>","PeriodicalId":18426,"journal":{"name":"Medicine and Science in Sports and Exercise","volume":" ","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142073144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}