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Leaf A, Rothschild JA, Sharpe TM, Sims ST, Macias CJ, Futch GG, Roberts MD, Stout JR, Ormsbee MJ, Aragon AA, Campbell BI, Arent SM, D’Agostino DP, Barrack MT, Kerksick CM, Kreider RB, Kalman DS, Antonio J. International society of sports nutrition position stand: ketogenic diets. J Int Soc Sports Nutr 2024; 21:2368167. [PMID: 38934469 PMCID: PMC11212571 DOI: 10.1080/15502783.2024.2368167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
POSITION STATEMENT The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the use of a ketogenic diet in healthy exercising adults, with a focus on exercise performance and body composition. However, this review does not address the use of exogenous ketone supplements. The following points summarize the position of the ISSN. 1. A ketogenic diet induces a state of nutritional ketosis, which is generally defined as serum ketone levels above 0.5 mM. While many factors can impact what amount of daily carbohydrate intake will result in these levels, a broad guideline is a daily dietary carbohydrate intake of less than 50 grams per day. 2. Nutritional ketosis achieved through carbohydrate restriction and a high dietary fat intake is not intrinsically harmful and should not be confused with ketoacidosis, a life-threatening condition most commonly seen in clinical populations and metabolic dysregulation. 3. A ketogenic diet has largely neutral or detrimental effects on athletic performance compared to a diet higher in carbohydrates and lower in fat, despite achieving significantly elevated levels of fat oxidation during exercise (~1.5 g/min). 4. The endurance effects of a ketogenic diet may be influenced by both training status and duration of the dietary intervention, but further research is necessary to elucidate these possibilities. All studies involving elite athletes showed a performance decrement from a ketogenic diet, all lasting six weeks or less. Of the two studies lasting more than six weeks, only one reported a statistically significant benefit of a ketogenic diet. 5. A ketogenic diet tends to have similar effects on maximal strength or strength gains from a resistance training program compared to a diet higher in carbohydrates. However, a minority of studies show superior effects of non-ketogenic comparators. 6. When compared to a diet higher in carbohydrates and lower in fat, a ketogenic diet may cause greater losses in body weight, fat mass, and fat-free mass, but may also heighten losses of lean tissue. However, this is likely due to differences in calorie and protein intake, as well as shifts in fluid balance. 7. There is insufficient evidence to determine if a ketogenic diet affects males and females differently. However, there is a strong mechanistic basis for sex differences to exist in response to a ketogenic diet.
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Affiliation(s)
- Alex Leaf
- Alex Leaf LLC, Scientific Affairs, Scottsdale, AZ, USA
| | - Jeffrey A. Rothschild
- Auckland University of Technology, Sports Performance Research Institute New Zealand, Auckland, New Zealand
- High Performance Sport New Zealand, Performance Nutrition, Auckland, New Zealand
| | - Tim M. Sharpe
- University of Western States, Human Nutrition and Functional Medicine, Portland, OR, USA
| | - Stacy T. Sims
- Auckland University of Technology, Sports Performance Research Institute New Zealand, Auckland, New Zealand
- Stanford University, Stanford Lifestyle Medicine, Palo Alto, CA, USA
| | - Chad J. Macias
- University of Western States, Human Nutrition and Functional Medicine, Portland, OR, USA
| | - Geoff G. Futch
- Springfield College, Department of Exercise Science and Athletic Training, Springfield, MA, USA
- FitPro Analytics, Scientific Affairs, Springfield, MA, USA
| | | | - Jeffrey R. Stout
- University of Central Florida, School of Kinesiology and Rehabilitation Sciences, Orlando, FL, USA
| | - Michael J. Ormsbee
- Florida State University, Institute of Sports Sciences & Medicine, Tallahassee, FL, USA
- University of KwaZulu Natal, Discipline of Biokinetics, Exercise and Leisure Sciences, Durban, South Africa
| | | | - Bill I. Campbell
- University of South Florida, Performance and Physique Enhancement Laboratory, Exercise Science Program, Tampa, FL, USA
| | - Shawn M. Arent
- University of South Carolina, Department of Exercise Science, Arnold School of Public Health, Columbia, SC, USA
| | - Dominic P. D’Agostino
- Institute for Human and Machine Cognition, Human Healthspan, Resilience, and Performance, Pensacola, FL, USA
- University of South Florida, Department of Molecular Pharmacology and Physiology, Tampa, FL, USA
| | - Michelle T. Barrack
- California State University, Department of Family and Consumer Sciences, Long Beach, CA, USA
| | - Chad M. Kerksick
- Lindenwood University, Exercise and Performance Nutrition Laboratory, College of Science, Technology, and Health, St. Charles, MO, USA
| | - Richard B. Kreider
- Texas A&M University, Exercise and Sport Nutrition Lab, Department of Kinesiology and Sports Management, College Station, TX, USA
| | - Douglas S. Kalman
- Nova Southeastern University, Department of Nutrition. Dr. Kiran C. Patel College of Osteopathic Medicine. Davie, FL, USA
| | - Jose Antonio
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
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Xie Y, Gu Y, Li Z, He B, Zhang L. Effects of Different Exercises Combined with Different Dietary Interventions on Body Composition: A Systematic Review and Network Meta-Analysis. Nutrients 2024; 16:3007. [PMID: 39275322 PMCID: PMC11397086 DOI: 10.3390/nu16173007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2024] [Revised: 08/28/2024] [Accepted: 09/03/2024] [Indexed: 09/16/2024] Open
Abstract
BACKGROUND Exercise and dietary interventions are essential for maintaining weight and reducing fat accumulation. With the growing popularity of various dietary strategies, evidence suggests that combining exercise with dietary interventions offers greater benefits than either approach alone. Consequently, this combined strategy has become a preferred method for many individuals aiming to maintain health. Calorie restriction, 5/2 intermittent fasting, time-restricted feeding, and the ketogenic diet are among the most popular dietary interventions today. Aerobic exercise, resistance training, and mixed exercise are the most widely practiced forms of physical activity. Exploring the best combinations of these approaches to determine which yields the most effective results is both meaningful and valuable. Despite this trend, a comparative analysis of the effects of different exercise and diet combinations is lacking. This study uses network meta-analysis to evaluate the impact of various combined interventions on body composition and to compare their efficacy. METHODS We systematically reviewed literature from database inception through May 2024, searching PubMed, Web of Science, Embase, and the Cochrane Library. The study was registered in PROSPERO under the title: "Effects of Exercise Combined with Different Dietary Interventions on Body Composition: A Systematic Review and Network Meta-Analysis" (identifier: CRD42024542184). Studies were meticulously selected based on specific inclusion and exclusion criteria (The included studies must be randomized controlled trials involving healthy adults aged 18 to 65 years. Articles were rigorously screened according to the specified inclusion and exclusion criteria.), and their risk of bias was assessed using the Cochrane risk of bias tool. Data were aggregated and analyzed using network meta-analysis, with intervention efficacy ranked by Surface Under the Cumulative Ranking (SUCRA) curves. RESULTS The network meta-analysis included 78 randomized controlled trials with 5219 participants, comparing the effects of four combined interventions: exercise with calorie restriction (CR+EX), exercise with time-restricted eating (TRF+EX), exercise with 5/2 intermittent fasting (5/2F+EX), and exercise with a ketogenic diet (KD+EX) on body composition. Intervention efficacy ranking was as follows: (1) Weight Reduction: CR+EX > KD+EX > TRF+EX > 5/2F+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 2.94 (-3.64, 9.52); 2.37 (-0.40, 5.15); 1.80 (-1.75, 5.34)). (2) BMI: CR+EX > KD+EX > 5/2F+EX > TRF+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 1.95 (-0.49, 4.39); 2.20 (1.08, 3.32); 1.23 (-0.26, 2.71)). (3) Body Fat Percentage: CR+EX > 5/2F+EX > TRF+EX > KD+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 2.66 (-1.56, 6.89); 2.84 (0.56, 5.13); 3.14 (0.52, 5.75).). (4) Lean Body Mass in Male: CR+EX > TRF+EX > KD+EX (Relative to CR+EX, the effect sizes of TRF+EX and KD+EX are -1.60 (-6.98, 3.78); -2.76 (-7.93, 2.40)). (5) Lean Body Mass in Female: TRF+EX > CR+EX > 5/2F+EX > KD+EX (Relative to TRF+EX, the effect sizes of CR+EX, 5/2F+EX and KD+EX are -0.52 (-2.58, 1.55); -1.83 (-4.71, 1.04); -2.46 (-5.69,0.76).). CONCLUSION Calorie restriction combined with exercise emerged as the most effective strategy for reducing weight and fat percentage while maintaining lean body mass. For women, combining exercise with time-restricted eating proved optimal for preserving muscle mass. While combining exercise with a ketogenic diet effectively reduces weight, it is comparatively less effective at decreasing fat percentage and preserving lean body mass. Hence, the ketogenic diet combined with exercise is considered suboptimal.
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Affiliation(s)
- Yongchao Xie
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou 450001, China
| | - Yu Gu
- Henan Sports Medicine and Rehabilitation Center, Henan Sport University, Zhengzhou 450044, China
| | - Zhen Li
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou 450001, China
| | - Bingchen He
- Department of Physical Education, South China University of Technology, Guangzhou 510641, China
| | - Lei Zhang
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou 450001, China
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Burén J, Svensson M, Liv P, Sjödin A. Effects of a Ketogenic Diet on Body Composition in Healthy, Young, Normal-Weight Women: A Randomized Controlled Feeding Trial. Nutrients 2024; 16:2030. [PMID: 38999778 PMCID: PMC11243114 DOI: 10.3390/nu16132030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 06/13/2024] [Accepted: 06/24/2024] [Indexed: 07/14/2024] Open
Abstract
This study investigates the effects of a ketogenic low-carbohydrate high-fat (LCHF) diet on body composition in healthy, young, normal-weight women. With the increasing interest in ketogenic diets for their various health benefits, this research aims to understand their impact on body composition, focusing on women who are often underrepresented in such studies. Conducting a randomized controlled feeding trial with a crossover design, this study compares a ketogenic LCHF diet to a Swedish National Food Agency (NFA)-recommended control diet over four weeks. Seventeen healthy, young, normal-weight women adhered strictly to the provided diets, with ketosis confirmed through blood β-hydroxybutyrate concentrations. Dual-energy X-ray absorptiometry (DXA) was utilized for precise body composition measurements. To avoid bias, all statistical analyses were performed blind. The findings reveal that the ketogenic LCHF diet led to a significant reduction in both lean mass (-1.45 kg 95% CI: [-1.90;-1.00]; p < 0.001) and fat mass (-0.66 kg 95% CI: [-1.00;-0.32]; p < 0.001) compared to the control diet, despite similar energy intake and physical activity levels. This study concludes that while the ketogenic LCHF diet is effective for weight loss, it disproportionately reduces lean mass over fat mass, suggesting the need for concurrent strength training to mitigate muscle loss in women following this diet.
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Affiliation(s)
- Jonas Burén
- Department of Food, Nutrition and Culinary Science, Umeå University, 90187 Umeå, Sweden;
- Umeå School of Sport Sciences, Umeå University, 90187 Umeå, Sweden;
| | - Michael Svensson
- Umeå School of Sport Sciences, Umeå University, 90187 Umeå, Sweden;
- Department of Community Medicine and Rehabilitation, Section of Sports Medicine, Umeå University, 90187 Umeå, Sweden
| | - Per Liv
- Department of Public Health and Clinical Medicine, Section of Sustainable Health, Umeå University, 90187 Umeå, Sweden;
| | - Anna Sjödin
- Department of Food, Nutrition and Culinary Science, Umeå University, 90187 Umeå, Sweden;
- Umeå School of Sport Sciences, Umeå University, 90187 Umeå, Sweden;
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Staśkiewicz-Bartecka W, Kardas M, Zydek G, Zając A, Chycki J. Changes in Body Composition and Nutritional Periodization during the Training Macrocycle in Football-A Narrative Review. Nutrients 2024; 16:1332. [PMID: 38732581 PMCID: PMC11085159 DOI: 10.3390/nu16091332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 04/23/2024] [Accepted: 04/27/2024] [Indexed: 05/13/2024] Open
Abstract
Nutrition periodization in football training is an important determinant of adaptation to cyclic training loads. Personalizing an athlete's diet is crucial to ensure optimal performance and body composition, depending on the phase of training. The purpose of this review is to answer the question of how the body composition of football players changes over the training macrocycle and how dietary recommendations should be tailored to specific training periods. The review of scientific evidence was conducted based on the available literature, typing in phrases related to training and nutrition periodization using the PubMed and Google Scholar database methodology tools. A literature search resulted in the selection of 346 sources directly related to the topic of the study, and then those with the highest scientific value were selected. There is a need to adjust energy and nutrient intake according to the different training phases in a football player's preparation cycle. During the preparatory phase, it is recommended to increase protein and energy intake to support anabolic processes and muscle mass development. During the competitive period, due to the intensity of matches and training, the importance of carbohydrates for glycogen replenishment and recovery is emphasized. The transition phase requires the regulation of caloric intake to prevent adverse changes in body composition. Hydration has been identified as a key element in each phase of training. Cooperation between coaches, nutritionists, and players is essential to optimize sports performance and rapid recovery, and the authors recommend continuous adaptation and nutritional optimization as an integral part of football training.
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Affiliation(s)
- Wiktoria Staśkiewicz-Bartecka
- Department of Food Technology and Quality Evaluation, Department of Dietetics, Faculty of Public Health in Bytom, Medical University of Silesia in Katowice, ul. Jordana 19, 41-808 Zabrze, Poland;
| | - Marek Kardas
- Department of Food Technology and Quality Evaluation, Department of Dietetics, Faculty of Public Health in Bytom, Medical University of Silesia in Katowice, ul. Jordana 19, 41-808 Zabrze, Poland;
| | - Grzegorz Zydek
- Department of Sport Nutrition, Jerzy Kukuczka Academy of Physical Education in Katowice, ul. Mikołowska 72A, 40-065 Katowice, Poland;
| | - Adam Zając
- Department of Sports Training, Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice, ul. Mikołowska 72A, 40-065 Katowice, Poland; (A.Z.); (J.C.)
| | - Jakub Chycki
- Department of Sports Training, Institute of Sport Sciences, Jerzy Kukuczka Academy of Physical Education in Katowice, ul. Mikołowska 72A, 40-065 Katowice, Poland; (A.Z.); (J.C.)
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5
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Siddiqui R, Qaisar R, Al-Dahash K, Altelly AH, Elmoselhi AB, Khan NA. Cardiovascular changes under the microgravity environment and the gut microbiome. LIFE SCIENCES IN SPACE RESEARCH 2024; 40:89-96. [PMID: 38245353 DOI: 10.1016/j.lssr.2023.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 08/31/2023] [Accepted: 09/04/2023] [Indexed: 01/22/2024]
Abstract
In view of the critical role the gut microbiome plays in human health, it has become clear that astronauts' gut microbiota composition changes after spending time in space. Astronauts are exposed to several risks in space, including a protracted period of microgravity, radiation, and mechanical unloading of the body. Several deleterious effects of such an environment are reported, including orthostatic intolerance, cardiovascular endothelial dysfunction, cellular and molecular changes, and changes in the composition of the gut microbiome. Herein, the correlation between the gut microbiome and cardiovascular disease in a microgravity environment is evaluated. Additionally, the relationship between orthostatic hypotension, cardiac shrinkage and arrhythmias during spaceflight, and cellular alterations during spaceflight is reviewed. Given its impact on human health in general, modifying the gut microbiota may significantly promote astronaut health and performance. This is merited, given the prospect of augmented human activities in future space missions.
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Affiliation(s)
- Ruqaiyyah Siddiqui
- Microbiota Research Center, Istinye University, Istanbul 34010, Turkey; College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates
| | - Rizwan Qaisar
- Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates; Cardiovascular Research Group, Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Khulood Al-Dahash
- Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Ahmad Hashem Altelly
- Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Adel B Elmoselhi
- Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates; Cardiovascular Research Group, Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Naveed Ahmed Khan
- Microbiota Research Center, Istinye University, Istanbul 34010, Turkey.
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Homer KA, Cross MR, Helms ER. Peak Week Carbohydrate Manipulation Practices in Physique Athletes: A Narrative Review. SPORTS MEDICINE - OPEN 2024; 10:8. [PMID: 38218750 PMCID: PMC10787737 DOI: 10.1186/s40798-024-00674-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 01/02/2024] [Indexed: 01/15/2024]
Abstract
BACKGROUND Physique athletes are ranked by a panel of judges against the judging criteria of the corresponding division. To enhance on-stage presentation and performance, competitors in certain categories (i.e. bodybuilding and classic physique) achieve extreme muscle size and definition aided by implementing acute "peaking protocols" in the days before competition. Such practices can involve manipulating nutrition and training variables to increase intramuscular glycogen and water while minimising the thickness of the subcutaneous layer. Carbohydrate manipulation is a prevalent strategy utilised to plausibly induce muscle glycogen supercompensation and subsequently increase muscle size. The relationship between carbohydrate intake and muscle glycogen saturation was first examined in endurance event performance and similar strategies have been adopted by physique athletes despite the distinct physiological dissimilarities and aims between the sports. OBJECTIVES The aim of this narrative review is to (1) critically examine and appraise the existing scientific literature relating to carbohydrate manipulation practices in physique athletes prior to competition; (2) identify research gaps and provide direction for future studies; and (3) provide broad practical applications based on the findings and physiological reasoning for coaches and competitors. FINDINGS The findings of this review indicate that carbohydrate manipulation practices are prevalent amongst physique athletes despite a paucity of experimental evidence demonstrating the efficacy of such strategies on physique performance. Competitors have also been observed to manipulate water and electrolytes in conjunction with carbohydrate predicated on speculative physiological mechanisms which may be detrimental for performance. CONCLUSIONS Further experimental evidence which closely replicates the nutritional and training practices of physique athletes during peak week is required to make conclusions on the efficacy of carbohydrate manipulation strategies. Quasi-experimental designs may be a feasible alternative to randomised controlled trials to examine such strategies due to the difficulty in recruiting the population of interest. Finally, we recommend that coaches and competitors manipulate as few variables as possible, and experiment with different magnitudes of carbohydrate loads in advance of competition if implementing a peaking strategy.
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Affiliation(s)
- Kai A Homer
- Sport Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, 17 Antares Place, Rosedale, Auckland, 0632, New Zealand.
| | - Matt R Cross
- Sport Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, 17 Antares Place, Rosedale, Auckland, 0632, New Zealand
| | - Eric R Helms
- Sport Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, 17 Antares Place, Rosedale, Auckland, 0632, New Zealand
- Department of Exercise Science and Health Promotion, Muscle Physiology Laboratory, Florida Atlantic University, Boca Raton, FL, USA
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Pérez-Castillo ÍM, Williams JA, López-Chicharro J, Mihic N, Rueda R, Bouzamondo H, Horswill CA. Compositional Aspects of Beverages Designed to Promote Hydration Before, During, and After Exercise: Concepts Revisited. Nutrients 2023; 16:17. [PMID: 38201848 PMCID: PMC10781183 DOI: 10.3390/nu16010017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/14/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Hypohydration can impair aerobic performance and deteriorate cognitive function during exercise. To minimize hypohydration, athletes are recommended to commence exercise at least euhydrated, ingest fluids containing sodium during long-duration and/or high-intensity exercise to prevent body mass loss over 2% and maintain elevated plasma osmolality, and rapidly restore and retain fluid and electrolyte homeostasis before a second exercise session. To achieve these goals, the compositions of the fluids consumed are key; however, it remains unclear what can be considered an optimal formulation for a hydration beverage in different settings. While carbohydrate-electrolyte solutions such as sports drinks have been extensively explored as a source of carbohydrates to meet fuel demands during intense and long-duration exercise, these formulas might not be ideal in situations where fluid and electrolyte balance is impaired, such as practicing exercise in the heat. Alternately, hypotonic compositions consisting of moderate to high levels of electrolytes (i.e., ≥45 mmol/L), mainly sodium, combined with low amounts of carbohydrates (i.e., <6%) might be useful to accelerate intestinal water absorption, maintain plasma volume and osmolality during exercise, and improve fluid retention during recovery. Future studies should compare hypotonic formulas and sports drinks in different exercise settings, evaluating different levels of sodium and/or other electrolytes, blends of carbohydrates, and novel ingredients for addressing hydration and rehydration before, during, and after exercise.
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Affiliation(s)
| | | | | | - Niko Mihic
- Real Madrid, Medical Services, 28055 Madrid, Spain; (J.L.-C.); (N.M.)
| | | | | | - Craig A. Horswill
- Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60608, USA;
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Serra-Prat M, Lorenzo I, Martínez J, Palomera E, Pleguezuelos E, Ferrer P. Relationship between Hydration Status and Muscle Catabolism in the Aged Population: A Cross-Sectional Study. Nutrients 2023; 15:4718. [PMID: 38004111 PMCID: PMC10674909 DOI: 10.3390/nu15224718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/02/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
BACKGROUND The physiopathology of sarcopenia is still not completely understood. AIM To assess the relationship between dehydration and skeletal muscle catabolism, muscle mass, and sarcopenia in an aged population. METHODS Observational cross-sectional study of community-dwelling subjects aged 70 years and older. Dehydration was assessed by plasma osmolarity; bioimpedance analysis (BIA) was used to assess body composition and water content; sarcopenia was established according to the EWGSOP-2 criteria; and 3-methyl-histidine (3MH) was used as an indicator of muscle catabolism. RESULTS 190 participants were recruited (77.4 years; 51.6% women). In total, 22.6% and 20.5% presented plasma osmolarity of 295-300 mOsm/L and >300 mOsm/L, respectively. Age was correlated with plasma osmolarity (rs = 0.439; p < 0.001). Plasma osmolarity was correlated with 3MH (rs = 0.360; p < 0.001) and showed an effect on 3MH levels, with an adjusted (by age, sex, and number of medications) beta of 0.283 (p < 0.001). BIA water content indicators showed no correlation with 3MH. Lower in sarcopenic compared to non-sarcopenic subjects were the intracellular water percentage (60.3 vs. 61.2%; p = 0.004) and intracellular water/free-fat mass ratio (44.3 vs. 45.0; p = 0.004). CONCLUSIONS Dehydration is a highly prevalent clinical condition in aged populations, increases with age, and is associated with muscle catabolism but not sarcopenia.
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Affiliation(s)
- Mateu Serra-Prat
- Research Unit, Consorci Sanitari del Maresme, 08304 Mataró, Barcelona, Spain;
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Instituto de Salud Carlos III, 28222 Majadahonda, Madrid, Spain
| | - Isabel Lorenzo
- Information Management Unit, Consorci Sanitari del Maresme, 08304 Mataró, Barcelona, Spain;
| | - Jessica Martínez
- Dietetics and Nutritional Unit, Consorci Sanitari del Maresme, 08304 Mataró, Barcelona, Spain;
| | - Elisabet Palomera
- Research Unit, Consorci Sanitari del Maresme, 08304 Mataró, Barcelona, Spain;
| | - Eulogio Pleguezuelos
- Rehabilitation Department, Hospital of Mataró, Consorci Sanitari del Maresme, 08304 Mataró, Barcelona, Spain;
| | - Pau Ferrer
- Tecnocampus Foundation, 08302 Mataró, Barcelona, Spain;
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Wu D, Qu C, Huang P, Geng X, Zhang J, Shen Y, Rao Z, Zhao J. Water Intake and Handgrip Strength in US Adults: A Cross-Sectional Study Based on NHANES 2011-2014 Data. Nutrients 2023; 15:4477. [PMID: 37892552 PMCID: PMC10609934 DOI: 10.3390/nu15204477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/09/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
This study aimed to examine the relationship between daily total intake of water (DTIW) and handgrip strength (HGS) among US adults and to explore the impact of water intake on muscle function and health, providing a reference for public health policies and health education. Using the data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014, a cross-sectional survey design was adopted to analyze 5427 adults (48.37% female and 51.63% male) aged 20 years and above. DTIW was assessed using two non-consecutive 24 h dietary recall interviews, and the HGS level was measured using a Takei Dynamometer. Weighted generalized linear regression models and restricted cubic spline plots were used to analyze the linear and nonlinear associations between DTIW and HGS level and to conduct a gender subgroup analysis and an interaction effect test. The results showed that there were significant differences in HGS and other characteristics among different quartile groups of DTIW (p < 0.05). There was a significant nonlinear trend (exhibiting an inverted U-curve) between DTIW and HGS (p for nonlinear = 0.0044), with a cut-off point of 2663 g/day. Gender subgroup analysis showed that the nonlinear trend (exhibiting an inverted U-curve) was significant only in males (p for nonlinear = 0.0016), with a cut-off point of 2595 g/day. None of the stratified variables had an interaction effect on the association between DTIW and HGS (p for interaction > 0.05). In conclusion, this study found a nonlinear association between DTIW and HGS levels, as well as a gender difference. This finding provides new clues and directions for exploring the mechanism of the impact of DTIW on muscle function and health and also provides new evidence and suggestions for adults to adjust their water intake reasonably.
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Affiliation(s)
- Dongzhe Wu
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
| | - Chaoyi Qu
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
- Department of Exercise Physiology, Beijing Sport University, Beijing 100084, China
| | - Peng Huang
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
- School of Exercise and Health, Shanghai University of Sport, Shanghai 200438, China
| | - Xue Geng
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
- Department of Exercise Physiology, Beijing Sport University, Beijing 100084, China
| | - Jianhong Zhang
- National Institute of Sports Medicine, Beijing 100763, China;
| | - Yulin Shen
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
- Department of Exercise Physiology, Beijing Sport University, Beijing 100084, China
| | - Zhijian Rao
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
- College of Physical Education, Shanghai Normal University, Shanghai 200233, China
| | - Jiexiu Zhao
- Exercise Biological Center, China Institute of Sport Science, Beijing 100061, China; (D.W.); (C.Q.); (P.H.); (X.G.); (Y.S.); (Z.R.)
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10
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López-Torres O, Rodríguez-Longobardo C, Escribano-Tabernero R, Fernández-Elías VE. Hydration, Hyperthermia, Glycogen, and Recovery: Crucial Factors in Exercise Performance-A Systematic Review and Meta-Analysis. Nutrients 2023; 15:4442. [PMID: 37892517 PMCID: PMC10610078 DOI: 10.3390/nu15204442] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
Hyperthermia accelerates dehydration and can lead to a glycolysis malfunction. Therefore, to deeply understand the relationship between dehydration and hyperthermia during exercise, as well as in the recovery time, there might be important factors to improve athletic performance. A systematic review was carried out in different databases using the words "hydration" OR "dehydration" AND "glycogen" OR "glycogenesis" OR "glycogenolysis" AND "muscle" OR "muscle metabolism" OR "cardiovascular system" and adding them to the "topic section" in Web of Science, to "Title/Abstract" in PubMed and to "Abstract" in SPORTDiscus. A total of 18 studies were included in the review and 13 in the meta-analysis. The free statistical software Jamovi was used to run the meta-analysis (version 1.6.15). A total sample of 158 people was included in the qualitative analysis, with a mean age of 23.5 years. Ten studies compared muscle glycogen content after hydration vs. remaining dehydrated (SMD -4.77 to 3.71, positive 80% of estimates, \hat{\mu} = 0.79 (95% CI: -0.54 to 2.12), z = 1.17, p = 0.24, Q-test (Q(9) = 66.38, p < 0.0001, tau2 = 4.14, I2 = 91.88%). Four studies examined the effect of temperature on postexercise muscle glycogen content (SMD -3.14 to -0.63, 100% of estimates being negative, \hat{\mu} = -1.52 (95% CI: -2.52 to -0.53), (z = -3.00, p = 0.003, Q-test (Q(3) = 8.40, p = 0.038, tau2 = 0.68, I2 = 66.81%). In conclusion, both hyperthermia and dehydration may contribute to elevated glycogenolysis during exercise and poor glycogen resynthesis during recovery. Although core and muscle hyperthermia are the key factors in glycogen impairments, they are also directly related to dehydration.
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Affiliation(s)
- Olga López-Torres
- Sports Department, Faculty of Physical Activity and Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (R.E.-T.); (V.E.F.-E.)
| | - Celia Rodríguez-Longobardo
- Social Sciences of Physical Activity, Sport and Leisure Department, Faculty of Physical Activity and Sport Sciences, Universidad Politécnica de Madrid, 28040 Madrid, Spain;
| | - Rodrigo Escribano-Tabernero
- Sports Department, Faculty of Physical Activity and Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (R.E.-T.); (V.E.F.-E.)
| | - Valentín E. Fernández-Elías
- Sports Department, Faculty of Physical Activity and Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (R.E.-T.); (V.E.F.-E.)
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11
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Trinschek J, Zieliński J, Zarębska EA, Kusy K. Male and female athletes matched for maximum oxygen uptake per skeletal muscle mass: equal but still different. J Sports Med Phys Fitness 2023; 63:95-103. [PMID: 35230070 DOI: 10.23736/s0022-4707.22.13605-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND We matched highly trained competitive male and female athletes using maximal oxygen uptake (V̇O<inf>2max</inf>) per kg skeletal muscle mass (SMM) to show sex differences in factors limiting V̇O<inf>2max</inf>. METHODS Thirteen highly trained male (28±3.0 yr) vs. 13 female (21.3±3.0 yr) endurance athletes and 10 male (23.9±3.8 yr) vs. 10 female sprinters (21.9±3.3 yr) performed an incremental running treadmill test until exhaustion. Main cardiorespiratory variables were measured using ergospirometry. SMM was determined using the dual X-ray absorptiometry method and a regression equation based on measured appendicular lean soft tissue. Basic hematological parameters were obtained from capillary blood samples taken before exercise. RESULTS In both endurance and sprint groups, male athletes had significantly higher muscle mass (by 8-12%) and substantially lower total fat (by 55-58%). For almost all body composition indicators, the effect size of sex differences was very large (Cohens d>1.4). Male athletes obtained significantly higher values in cardiorespiratory variables (by 12-34%) and factors related to oxygen transport (9-13%). Cohens d of the revealed differences was large or very large in both groups (0.8-2.1 in sprinters and 0.8-2.3 in endurance athletes). CONCLUSIONS Male and female competitive athletes having the same V̇̇O<inf>2max</inf> per kg SMM strongly differ in main factors limiting maximum oxygen uptake. These differences are more pronounced in endurance- than in sprint-trained athletes. The strongest differences are seen for body composition (fat, lean, and muscle mass) and central cardiac factors.
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Affiliation(s)
- Jacek Trinschek
- Department of Athletics, Strength and Conditioning, Faculty of Sport Sciences, Poznan University of Physical Education, Poznań, Poland -
| | - Jacek Zieliński
- Department of Athletics, Strength and Conditioning, Faculty of Sport Sciences, Poznan University of Physical Education, Poznań, Poland
| | - Ewa A Zarębska
- Department of Athletics, Strength and Conditioning, Faculty of Sport Sciences, Poznan University of Physical Education, Poznań, Poland
| | - Krzysztof Kusy
- Department of Athletics, Strength and Conditioning, Faculty of Sport Sciences, Poznan University of Physical Education, Poznań, Poland
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12
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Muscle Glycogen Assessment and Relationship with Body Hydration Status: A Narrative Review. Nutrients 2022; 15:nu15010155. [PMID: 36615811 PMCID: PMC9823884 DOI: 10.3390/nu15010155] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/25/2022] [Accepted: 12/26/2022] [Indexed: 12/30/2022] Open
Abstract
Muscle glycogen is a crucial energy source for exercise, and assessment of muscle glycogen storage contributes to the adequate manipulation of muscle glycogen levels in athletes before and after training and competition. Muscle biopsy is the traditional and gold standard method for measuring muscle glycogen; alternatively, 13C magnetic resonance spectroscopy (MRS) has been developed as a reliable and non-invasive method. Furthermore, outcomes of ultrasound and bioimpedance methods have been reported to change in association with muscle glycogen conditions. The physiological mechanisms underlying this activity are assumed to involve a change in water content bound to glycogen; however, the relationship between body water and stored muscle glycogen is inconclusive. In this review, we discuss currently available muscle glycogen assessment methods, focusing on 13C MRS. In addition, we consider the involvement of muscle glycogen in changes in body water content and discuss the feasibility of ultrasound and bioimpedance outcomes as indicators of muscle glycogen levels. In relation to changes in body water content associated with muscle glycogen, this review broadens the discussion on changes in body weight and body components other than body water, including fat, during carbohydrate loading. From these discussions, we highlight practical issues regarding muscle glycogen assessment and manipulation in the sports field.
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13
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Abstract
Obesity remains a serious relevant public health concern throughout the world despite related countermeasures being well understood (i.e. mainly physical activity and an adjusted diet). Among different nutritional approaches, there is a growing interest in ketogenic diets (KD) to manipulate body mass (BM) and to enhance fat mass loss. KD reduce the daily amount of carbohydrate intake drastically. This results in increased fatty acid utilisation, leading to an increase in blood ketone bodies (acetoacetate, 3-β-hydroxybutyrate and acetone) and therefore metabolic ketosis. For many years, nutritional intervention studies have focused on reducing dietary fat with little or conflicting positive results over the long term. Moreover, current nutritional guidelines for athletes propose carbohydrate-based diets to augment muscular adaptations. This review discusses the physiological basis of KD and their effects on BM reduction and body composition improvements in sedentary individuals combined with different types of exercise (resistance training or endurance training) in individuals with obesity and athletes. Ultimately, we discuss the strengths and the weaknesses of these nutritional interventions together with precautionary measures that should be observed in both individuals with obesity and athletic populations. A literature search from 1921 to April 2021 using Medline, Google Scholar, PubMed, Web of Science, Scopus and Sportdiscus Databases was used to identify relevant studies. In summary, based on the current evidence, KD are an efficient method to reduce BM and body fat in both individuals with obesity and athletes. However, these positive impacts are mainly because of the appetite suppressive effects of KD, which can decrease daily energy intake. Therefore, KD do not have any superior benefits to non-KD in BM and body fat loss in individuals with obesity and athletic populations in an isoenergetic situation. In sedentary individuals with obesity, it seems that fat-free mass (FFM) changes appear to be as great, if not greater, than decreases following a low-fat diet. In terms of lean mass, it seems that following a KD can cause FFM loss in resistance-trained individuals. In contrast, the FFM-preserving effects of KD are more efficient in endurance-trained compared with resistance-trained individuals.
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14
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Evans C, Mekhail V, Curtis J, Czartoryski P, Kaminski J, Ellerbroek A, Bustillo E, Jiannine L, Santana JC, Antonio J. The Effects of 5-HTP on Body Composition: An 8-Week Preliminary RCT. J Diet Suppl 2022:1-10. [PMID: 35583055 DOI: 10.1080/19390211.2022.2076760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The purpose of this investigation was to determine the effects of supplementing with 100 mg daily of 5-Hydroxytryptophan (5-HTP) on indices of body composition in exercise-trained men and women. Sixty-one subjects volunteered for this investigation. Forty-eight subjects were randomized into a treatment (n = 31, 12 male/19 female; 100 mg 5-HTP daily; CLEANMOOD™) or a placebo (n = 17, six male/11 female; maltodextrin). Body composition was assessed pre- and post-treatment after eight weeks via a multi-frequency bioelectrical impedance device (InBody® 270). Subjects were instructed to not change their training or eating habits; moreover, they were instructed to track their diet ∼2-3 days per week using a mobile app (MyFitnessPal). There were no changes in food intake (i.e. total energy intake or grams of macronutrients) between or within groups. Lean body mass, total body water, and % body fat did not change significantly in either group. Fat mass decreased significantly post versus pre in the 5-HTP group (p = 0.02) but did not change in the placebo group (p = 0.58). Moreover, changes in fat mass were significantly different between the 5-HTP and placebo group (p = 0.048). Based on the limited data from this investigation, daily supplementation with 100 mg of 5-HTP may affect body composition.
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Affiliation(s)
- Cassandra Evans
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
| | - Veronica Mekhail
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
| | | | - Paulina Czartoryski
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
| | - Jackie Kaminski
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
| | - Anya Ellerbroek
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
| | | | - Lia Jiannine
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
| | | | - Jose Antonio
- Department of Health and Human Performance, Nova Southeastern University, Davie, FL, USA
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15
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Altered electrical properties in skeletal muscle of mice with glycogen storage disease type II. Sci Rep 2022; 12:5327. [PMID: 35351934 PMCID: PMC8964715 DOI: 10.1038/s41598-022-09328-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 03/14/2022] [Indexed: 01/15/2023] Open
Abstract
Electrical impedance methods, including electrical impedance myography, are increasingly being used as biomarkers of muscle health since they measure passive electrical properties of muscle that alter in disease. One disorder, Pompe Disease (Glycogen storage disease type II (GSDII)), remains relatively unstudied. This disease is marked by dramatic accumulation of intracellular myofiber glycogen. Here we assessed the electrical properties of skeletal muscle in a model of GSDII, the Pompe6neo/6neo (Pompe) mouse. Ex vivo impedance measurements of gastrocnemius (GA) were obtained using a dielectric measuring cell in 30-week-old female Pompe (N = 10) and WT (N = 10) mice. Longitudinal and transverse conductivity, σ, and the relative permittivity, εr, and Cole–Cole complex resistivity parameters at 0 Hz and infinite frequency, ρo and ρ∞, respectively, and the intracellular resistivity, ρintracellular were determined from the impedance data. Glycogen content (GC) was visualized histologically and quantified biochemically. At frequencies > 1 MHz, Pompe mice demonstrated significantly decreased longitudinal and transverse conductivity, increased Cole–Cole parameters, ρo and ρo-ρ∞, and decreased ρintracellular. Changes in longitudinal conductivity and ρintracellular correlated with increased GC in Pompe animals. Ex vivo high frequency impedance measures are sensitive to alterations in intracellular myofiber features considered characteristic of GSDII, making them potentially useful measures of disease status.
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16
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Yatsuhashi H, Furuyashiki T, Vo PHT, Kamasaka H, Kuriki T. Effects of Glycogen on Ceramide Production in Cultured Human Keratinocytes via Acid Sphingomyelinase Activation. J Appl Glycosci (1999) 2021; 68:41-46. [PMID: 34429698 PMCID: PMC8367632 DOI: 10.5458/jag.jag.jag-2020_0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 04/23/2021] [Indexed: 11/07/2022] Open
Abstract
Glycogen is a highly branched storage polysaccharide found mainly in the liver and the muscles. Glycogen is also present in the skin, but its functional role is poorly understood. Recently, it has been reported that glycogen plays an important role in intracellular signal transduction. In the epidermis of the skin, keratinocytes are the predominant cells that produce ceramide. Ceramides are lipids composed of sphingosine, and prevent water loss, as well as protecting the skin against environmental stressors. In this study, we investigated the effects of glycogen on ceramide production in cultured keratinocytes. Thin-layer chromatography revealed that incubation of keratinocytes with 2 % glycogen enhanced the cellular amount of ceramide NS (ceramide 2) by 3.4-fold compared to the control. We also found that glycogen regulated the mRNA expression levels of signaling molecules of the sphingomyelin-ceramide pathway by quantitative real-time PCR. The activity of sphingomyelinase was also significantly enhanced by 2.5-fold in cultures with 1 % glycogen compared to the control. Moreover, glycogen increased the ATP production by 1.5-fold compared to the control, while glucose did not affect the production. Western blotting showed that phosphorylation of Akt, a cellular signaling molecule, was inhibited in the presence of glycogen in cultured keratinocytes. This study shows that glycogen upregulates the ceramide production pathway from sphingomyelin in epidermal keratinocytes, and provides new insights into the role of glycogen in cellular signal transduction.
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17
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The Validity of Ultrasound Technology in Providing an Indirect Estimate of Muscle Glycogen Concentrations Is Equivocal. Nutrients 2021; 13:nu13072371. [PMID: 34371881 PMCID: PMC8308826 DOI: 10.3390/nu13072371] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/02/2021] [Accepted: 07/07/2021] [Indexed: 12/04/2022] Open
Abstract
Researchers and practitioners in sports nutrition would greatly benefit from a rapid, portable, and non-invasive technique to measure muscle glycogen, both in the laboratory and field. This explains the interest in MuscleSound®, the first commercial system to use high-frequency ultrasound technology and image analysis from patented cloud-based software to estimate muscle glycogen content from the echogenicity of the ultrasound image. This technique is based largely on muscle water content, which is presumed to act as a proxy for glycogen. Despite the promise of early validation studies, newer studies from independent groups reported discrepant results, with MuscleSound® scores failing to correlate with the glycogen content of biopsy-derived mixed muscle samples or to show the expected changes in muscle glycogen associated with various diet and exercise strategies. The explanation of issues related to the site of assessment do not account for these discrepancies, and there are substantial problems with the premise that the ratio of glycogen to water in the muscle is constant. Although further studies investigating this technique are warranted, current evidence that MuscleSound® technology can provide valid and actionable information around muscle glycogen stores is at best equivocal.
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18
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Januszko P, Lange E. Nutrition, supplementation and weight reduction in combat sports: a review. AIMS Public Health 2021; 8:485-498. [PMID: 34395698 PMCID: PMC8334642 DOI: 10.3934/publichealth.2021038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 06/29/2021] [Indexed: 11/18/2022] Open
Abstract
Nutrition is the aspect closely connected to physical activity and may affect body composition, sports performance and post-workout regeneration. Using an appropriate diet plan is a proven method to optimize performance improvements in combat sports. In the majority of combat sports athletes are classified according to their body mass in order to minimize differences between competitors. Many athletes induce weight loss in order to gain an advantage over their opponents. The review was undertaken to provide safe, evidence-based protocols helping athletes in weight reduction without negative effects on sports performance. The nutritional requirements for combat sports athletes, sports supplements, gradual and rapid weight reduction strategies are discussed in this review.
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Affiliation(s)
- Paulina Januszko
- Department of Dietetics, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences, SGGW, Warsaw, Poland
| | - Ewa Lange
- Department of Dietetics, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences, SGGW, Warsaw, Poland
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19
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Klement RJ, Koebrunner PS, Meyer D, Kanzler S, Sweeney RA. Impact of a ketogenic diet intervention during radiotherapy on body composition: IV. Final results of the KETOCOMP study for rectal cancer patients. Clin Nutr 2021; 40:4674-4684. [PMID: 34233255 DOI: 10.1016/j.clnu.2021.05.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/10/2021] [Accepted: 05/22/2021] [Indexed: 12/24/2022]
Abstract
BACKGROUND & AIMS Obesity and low muscle mass are associated with worse outcomes of colorectal cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in rectal cancer patients undergoing radiotherapy. METHODS Patients with non-metastasized rectal cancer were allocated to either the KD (N = 24) or the SD (N = 25) group during radiotherapy. Body composition was measured weekly by bioimpedance analysis and analyzed using linear mixed effects models. Pathologic response in patients undergoing neoadjuvant treatment was evaluated at the time of surgery. RESULTS A total of 18 KD and 23 SD patients completed the study and were eligible for analysis. The SD group experienced no noteworthy changes in any body composition parameter. In contrast, patients in the KD group lost significant amounts of body weight and fat mass, averaging 0.5 and 0.65 kg/week (p < 0.0001). There was a rapid loss of intracellular water consistent with initial intramuscular glycogen and water depletion, but skeletal muscle tissue was conserved. Pathological tumor responses were somewhat greater in the KD group, with a larger mean Dworak regression grade (p = 0.072) and larger percentage of near-complete (yT0N0 or yT1N1) responses (43 versus 15%, p = 0.116) that almost reached statistical significance in intention-to-treat analysis (50% versus 14%, p = 0.018). CONCLUSIONS In rectal cancer patients undergoing curative radiotherapy, a KD significantly reduced body weight and fat mass while preserving skeletal muscle mass. We could demonstrate a trend for KDs contributing synergistically to pathological tumor response, a finding in line with preclinical data that warrants future confirmation in larger studies. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015.
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Affiliation(s)
- Rainer J Klement
- Department of Radiation Oncology, Leopoldina Hospital, Schweinfurt, Germany.
| | - Petra S Koebrunner
- Department of Radiation Oncology, Leopoldina Hospital, Schweinfurt, Germany
| | - Detlef Meyer
- Darmkrebszentrum, Leopoldina Hospital, Schweinfurt, Germany
| | - Stefan Kanzler
- Darmkrebszentrum, Leopoldina Hospital, Schweinfurt, Germany
| | - Reinhart A Sweeney
- Department of Radiation Oncology, Leopoldina Hospital, Schweinfurt, Germany; Darmkrebszentrum, Leopoldina Hospital, Schweinfurt, Germany
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20
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Body Composition Over the Menstrual and Oral Contraceptive Cycle in Trained Females. Int J Sports Physiol Perform 2021; 16:375-381. [DOI: 10.1123/ijspp.2020-0038] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/07/2020] [Accepted: 04/16/2020] [Indexed: 11/18/2022]
Abstract
Purpose: The influence of female sex hormones on body fluid regulation and metabolism homeostasis has been widely studied. However, it remains unclear whether hormone fluctuations throughout the menstrual cycle (MC) and with oral contraceptive (OC) use affect body composition (BC). Thus, the aim of this study was to investigate BC over the MC and OC cycle in well-trained females. Methods: A total of 52 eumenorrheic and 33 monophasic OC-taking well-trained females participated in this study. Several BC variables were measured through bioelectrical impedance analysis 3 times in the eumenorrheic group (early follicular phase, late follicular phase, and midluteal phase) and on 2 occasions in the OC group (withdrawal phase and active pill phase). Results: Mixed linear model tests reported no significant differences in the BC variables (body weight, body mass index, basal metabolism, fat mass, fat-free mass, and total body water) between the MC phases or between the OC phases (P > .05 for all comparisons). Trivial and small effect sizes were found for all BC variables when comparing the MC phases in eumenorrheic females, as well as for the OC cycle phases. Conclusions: According to the results, sex hormone fluctuations throughout the menstrual and OC cycle do not influence BC variables measured by bioelectrical impedance in well-trained females. Therefore, it seems that bioimpedance analysis can be conducted at any moment of the cycle, both for eumenorrheic women and women using OC.
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21
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Ashtary-Larky D, Bagheri R, Asbaghi O, Tinsley GM, Kooti W, Abbasnezhad A, Afrisham R, Wong A. Effects of resistance training combined with a ketogenic diet on body composition: a systematic review and meta-analysis. Crit Rev Food Sci Nutr 2021; 62:5717-5732. [PMID: 33624538 DOI: 10.1080/10408398.2021.1890689] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We evaluated the effects of ketogenic diets (KDs) on body mass (BM), fat mass (FM), fat-free mass (FFM), body mass index (BMI), and body fat percentage (BFP) compared to non-KDs in individuals performing resistance training (RT). Online electronic databases including PubMed, the Cochrane Library, Web of Science, Embase, SCOPUS, and Ovid were searched to identify initial studies until February 2021. Data were pooled using both fixed and random-effects methods and were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). Out of 1372 studies, 13 randomized controlled trials (RCTs) that enrolled 244 volunteers were included. The pooled results demonstrated that KDs significantly decreased BM [(WMD = -3.67 kg; 95% CI: -4.44, -2.90, p < 0.001)], FM [(WMD = -2.21 kg; 95% CI: -3.09, -1.34, p < 0.001)], FFM [(WMD = -1.26 kg; 95% CI: -1.82, -0.70, p < 0.001)], BMI [(WMD = -1.37 kg.m-2; 95% CI: -2.14, -0.59, p = 0.022)], and BFP [(WMD = -2.27%; 95% CI: -3.63, -0.90, p = 0.001)] compared to non-KDs. We observed beneficial effects of KDs compared to non-KDs on BM and body fat (both FM and BFP) in individuals performing RT. However, adherence to KDs may have a negative effect on FFM, which is not ameliorated by the addition of RT.
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Affiliation(s)
- Damoon Ashtary-Larky
- Nutrition and Metabolic Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Reza Bagheri
- Department of Exercise Physiology, University of Isfahan, Isfahan, Iran
| | - Omid Asbaghi
- Student Research Committee, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Grant M Tinsley
- Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, Texas, USA
| | - Wesam Kooti
- Lung Diseases & Allergy Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Amir Abbasnezhad
- Nutritional Health Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Reza Afrisham
- Department of Clinical Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Alexei Wong
- Department of Health and Human Performance, Marymount University, Arlington, Texas, USA
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22
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Keith L, Seo CA, Rowsemitt C, Pfeffer M, Wahi M, Staggs M, Dudek J, Gower B, Carmody M. Ketogenic diet as a potential intervention for lipedema. Med Hypotheses 2020; 146:110435. [PMID: 33303304 DOI: 10.1016/j.mehy.2020.110435] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/06/2020] [Accepted: 11/24/2020] [Indexed: 02/06/2023]
Abstract
Lipedema (LI) is a common yet misdiagnosed condition, often misconstrued with obesity. LI affects women almost exclusively, and its painful and life-changing symptoms have long been thought to be resistant to the lifestyle interventions such as diet and exercise. In this paper, we discuss possible mechanisms by which patients adopting a ketogenic diet (KD) can alleviate many of the unwanted clinical features of LI. This paper is also an effort to provide evidence for the hypothesis of the potency of this dietary intervention for addressing the symptoms of LI. Specifically, we examine the scientific evidence of effectiveness of adopting a KD by patients to alleviate clinical features associated with LI, including excessive and disproportionate lower body adipose tissue (AT) deposition, pain, and reduction in quality of life (QoL). We also explore several clinical features of LI currently under debate, including the potential existence and nature of edema, metabolic and hormonal dysfunction, inflammation, and fibrosis. The effectiveness of a KD on addressing clinical features of LI has been demonstrated in human studies, and shows promise as an intervention for LI. We hope this paper leads to an improved understanding of optimal nutritional management for patients with LI and stimulates future research in this area of study.
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Affiliation(s)
- L Keith
- The Lipedema Project, Boston, MA, USA; Lipedema Simplified, Boston, MA, USA.
| | - C A Seo
- The Lipedema Project, Boston, MA, USA; Lipedema Simplified, Boston, MA, USA
| | - C Rowsemitt
- Lipedema Simplified, Boston, MA, USA; Comprehensive Weight Management, Templeton, CA and Providence, RI, USA; The Lipedema Project: Medical Advisory Board, Boston, MA, USA
| | - M Pfeffer
- Lipedema Simplified, Boston, MA, USA; The Lipedema Project: Medical Advisory Board, Boston, MA, USA; I Choose Health, Metung, Australia
| | - M Wahi
- DethWench Professional Services, Boston, MA, USA
| | - M Staggs
- Lipedema Simplified, Boston, MA, USA
| | - J Dudek
- The Lipedema Project: Medical Advisory Board, Boston, MA, USA; SWPS University of Social Sciences and Humanities, Warsaw, Poland
| | - B Gower
- University of Alabama at Birmingham, Department of Nutrition Sciences, Birmingham, AL, USA
| | - M Carmody
- Harvard Medical School, Boston, MA, USA
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Klement RJ, Champ CE, Kämmerer U, Koebrunner PS, Krage K, Schäfer G, Weigel M, Sweeney RA. Impact of a ketogenic diet intervention during radiotherapy on body composition: III-final results of the KETOCOMP study for breast cancer patients. Breast Cancer Res 2020; 22:94. [PMID: 32819413 PMCID: PMC7441712 DOI: 10.1186/s13058-020-01331-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/11/2020] [Indexed: 01/09/2023] Open
Abstract
Background Obesity and low muscle mass are associated with worse outcomes of breast cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in breast cancer patients undergoing radiotherapy. Methods Patients with non-metastasized breast cancer were allocated to either the KD (N = 32) or the SD (N = 31) during radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters and quality of life were assessed before, during, and at the end of radiotherapy. Results A total of 29 KD and 30 SD patients completed the study. During radiotherapy, mean and median fasting BHB concentrations in the KD group were 0.72 and 0.49 mmol/l (range 0.06–4.9) which was significantly higher than those in the SD group (p < 2.2 × 10−16). There was a very small and insignificant increase in body weight and fat mass in the SD group, as well as a decrease of fat free mass. In contrast, patients in the KD group lost body weight and fat free and skeletal muscle mass quickly after diet onset, which for the most part was related to water losses. The KD did not cause further substantial changes in fat free or skeletal muscle mass, but was associated with a gradual decrease of 0.4 kg body weight and fat mass per week (p < 0.0001). The KD significantly decreased free T3 levels by 0.06 pg/ml/week (p = 6.3 × 10−5). Global quality of life remained stable in the SD group but increased in the KD group from a score of 66.7 to 75.0 (p = 0.20). Conclusions In breast cancer patients undergoing curative radiotherapy, a KD based on natural foods is feasible. After initial water losses, the KD tends to reduce body weight and fat mass while preserving fat free and skeletal muscle mass. Trial registration ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015.
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Affiliation(s)
- Rainer J Klement
- Department of Radiation Oncology, Leopoldina Hospital, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany.
| | - Colin E Champ
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
| | - Ulrike Kämmerer
- Department of Obstetrics and Gynaecology, University Hospital of Würzburg, Würzburg, Germany
| | - Petra S Koebrunner
- Department of Radiation Oncology, Leopoldina Hospital, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany
| | - Kelley Krage
- Department of Radiation Oncology, Leopoldina Hospital, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany
| | - Gabriele Schäfer
- Department of Radiation Oncology, Leopoldina Hospital, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany
| | - M Weigel
- Department of Obstetrics and Gynaecology, Leopoldina Hospital, Breast Cancer Centre, Schweinfurt, Germany
| | - Reinhart A Sweeney
- Department of Radiation Oncology, Leopoldina Hospital, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany
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San-Millán I, Hill JC, Calleja-González J. Reply to Comment on: "Changes in Skeletal Muscle Glycogen Content in Professional Soccer Players before and after a Match by a Non-Invasive MuscleSound ® Technology. A Cross Sectional Pilot Study Nutrients 2020, 12(4), 971". Nutrients 2020; 12:E2066. [PMID: 32664622 PMCID: PMC7400906 DOI: 10.3390/nu12072066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 07/08/2020] [Indexed: 11/17/2022] Open
Abstract
In our paper published in this journal, we present a pilot study application of a novel way to "indirectly assess" skeletal muscle glycogen based on the methodology that we developed though high-frequency skeletal muscle ultrasound [...].
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Affiliation(s)
- Iñigo San-Millán
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Aurora, CO 80045, USA;
- Department of Human Physiology and Nutrition, University of Colorado, Colorado Springs, CO 80918, USA
| | - John C. Hill
- Department of Family Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA;
| | - Julio Calleja-González
- Laboratory of Analysis of Human Performance, Department of Physical Education and Sport, Faculty of Education, Sports Section, University of the Basque Country, 01007 Vitoria, Spain
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25
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Lopez P, Crosby BJ, Robetti BP, Turella DJP, Weber TAS, de Oliveira ML, Rech A. Effects of an 8-week resistance training intervention on plantar flexor muscle quality and functional capacity in older women: A randomised controlled trial. Exp Gerontol 2020; 138:111003. [PMID: 32562747 DOI: 10.1016/j.exger.2020.111003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/27/2020] [Accepted: 06/13/2020] [Indexed: 01/11/2023]
Abstract
The present study examined 8 weeks of resistance training and its effects on muscle quality measures, plantar flexor muscle strength, muscle thickness and functional capacity in older women. Moreover, we tested if changes in muscle quality were associated with functional capacity. Twenty-four older women (66.3 ± 5.8 years; 69.0 ± 3.0 kg; 25.3 ± 1.4 kg·m-2) were recruited to the study. After completion of the baseline assessment, participants were randomly assigned to either the resistance training (RET, n = 12) or an active control group (CTR, n = 12). Muscle quality was evaluated through muscle echo intensity (MQEI) and specific tension (MQST). Muscle thickness, unilateral plantar flexor muscle strength and functional tests were evaluated at baseline and after the training period. After 8 weeks, both MQEI and MQST did not respond to the intervention. Furthermore, significant changes in stair climb performance (P < 0.05) were not associated with plantar flexor-derived muscle quality (P > 0.05). Finally, significant gains in muscle hypertrophy were observed in the RET group (P < 0.01), while muscle strength failed to change significantly (P > 0.05). In conclusion, a resistance training program provided significant benefits in the stair climb test, unrelated to plantar flexor-derived muscle quality measures as previously demonstrated in quadriceps femoris.
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Affiliation(s)
- Pedro Lopez
- Exercise Medicine Research Institute, Edith Cowan University, Perth, Western Australia, Australia.
| | - Brendan James Crosby
- Exercise Medicine Research Institute, Edith Cowan University, Perth, Western Australia, Australia
| | | | | | | | | | - Anderson Rech
- Universidade de Caxias do Sul, Caxias do Sul, Rio Grande do Sul, Brazil
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26
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Routledge HE, Bradley WJ, Shepherd SO, Cocks M, Erskine RM, Close GL, Morton JP. Ultrasound Does Not Detect Acute Changes in Glycogen in Vastus Lateralis of Man. Med Sci Sports Exerc 2020; 51:2286-2293. [PMID: 31169793 DOI: 10.1249/mss.0000000000002052] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE To examine the validity of ultrasound (via cloud-based software that measures pixilation intensity according to a scale of 0-100) to noninvasively assess muscle glycogen in human skeletal muscle. METHODS In study 1, 14 professional male rugby league players competed in an 80-min competitive rugby league game. In study 2 (in a randomized repeated measures design), 16 recreationally active males completed an exhaustive cycling protocol to deplete muscle glycogen followed by 36 h of HIGH or LOW carbohydrate intake (8 g·kg vs 3 g·kg body mass). In both studies, muscle biopsies and ultrasound scans were obtained from the vastus lateralis (at 50% of the muscle length) before and after match play in study 1 and at 36 h after glycogen depletion in study 2. RESULTS Despite match play reducing (P < 0.01) muscle glycogen concentration (pregame: 443 ± 65; postgame: 271 ± 94 mmol·kg dw, respectively) in study 1, there were no significant changes (P = 0.4) in ultrasound scores (pregame: 47 ± 6, postgame: 49 ± 7). In study 2, muscle glycogen concentration was significantly different (P < 0.01) between HIGH (531 ±129 mmol·kg dw) and LOW (252 ± 64 mmol·kg dw) yet there was no difference (P = 0.9) in corresponding ultrasound scores (HIGH: 56 ± 7, LOW: 54 ± 6). In both studies, no significant correlations (P > 0.05) were present between changes in muscle glycogen concentration and changes in ultrasound scores. CONCLUSIONS Data demonstrate that ultrasound (as based on measures of pixilation intensity) is not valid to measure muscle glycogen status within the physiological range (i.e., 200-500 mmol·kg dw) that is applicable to exercise-induced muscle glycogen utilization and postexercise muscle glycogen resynthesis.
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Affiliation(s)
- Harry E Routledge
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM
| | - Warren J Bradley
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM
| | - Sam O Shepherd
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM
| | - Matthew Cocks
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM
| | - Robert M Erskine
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM.,Institute of Sport, Exercise and Health, University College London, London, UNITED KINGDOM
| | - Graeme L Close
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM
| | - James P Morton
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM
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27
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Serra-Prat M, Lorenzo I, Papiol M, Palomera E, Bartolomé M, Pleguezuelos E, Burdoy E. Intracellular Water Content in Lean Mass as an Indicator of Muscle Quality in an Older Obese Population. J Clin Med 2020; 9:jcm9051580. [PMID: 32455974 PMCID: PMC7290582 DOI: 10.3390/jcm9051580] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/04/2020] [Accepted: 05/19/2020] [Indexed: 02/07/2023] Open
Abstract
Background: In aged populations, muscle strength depends more on muscle quality than on muscle quantity, while all three are criteria for the diagnosis of sarcopenia. Intracellular water content (ICW) in lean mass (LM) has been proposed as an indicator of muscle quality related to muscle strength in older people. Objectives: To evaluate the relationship between the ICW/LM ratio, muscle strength and indicators of functional performance in obese older adults, and to assess the value of the ICW/LM ratio as an indicator of muscle quality. Methodology: Design: cross-sectional study. Population: persons aged 65–75 years with a body mass index of 30–39 kg/m2. ICW and LM were estimated by bioelectrical impedance. Hand grip, gait speed, unipedal stance test, timed up-and-go (TUG) test, Barthel score and frailty (Fried criteria) were assessed. Sarcopenia was established according to EWGSOP2 criteria. Results: Recruited were 305 subjects (66% women), mean age 68 years. The ICW/LM ratio correlated with the TUG test, gait speed and grip strength, and was also associated with sex, the unipedal stance test and frailty. Independently of age, sex and muscle mass, the ICW/LM ratio was related with gait speed, the TUG test and unipedal stance capacity. One person (0.3%) had sarcopenia defined as low muscle strength and low muscle mass, while 25 people (8.2%) had sarcopenia defined as low muscle strength and poor muscle quality (ICW/LM). With this last definition, sarcopenia was related to frailty, gait speed and the TUG test. Conclusions: ICW content in LM could be a useful muscle quality indicator for defining sarcopenia. However, more studies are required to confirm our findings for other populations.
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Affiliation(s)
- Mateu Serra-Prat
- Research Unit, Consorci Sanitari del Maresme, Mataró, 08304 Barcelona, Spain; (I.L.); (E.P.)
- Institut de Recerca Germans Trias i Pujol (IGTP), Badalona, 08916 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), ISCIII, 08304 Barcelona, Spain
- Correspondence: ; Tel.: +34-(93)-741-7730
| | - Isabel Lorenzo
- Research Unit, Consorci Sanitari del Maresme, Mataró, 08304 Barcelona, Spain; (I.L.); (E.P.)
- Universitat de Vic-Universitat Central de Catalunya, 08500 Barcelona, Spain
| | - Mònica Papiol
- ABS Argentona, Consorci Sanitari del Maresme, Argentona, 08310 Barcelona, Spain; (M.P.); (E.B.)
| | - Elisabet Palomera
- Research Unit, Consorci Sanitari del Maresme, Mataró, 08304 Barcelona, Spain; (I.L.); (E.P.)
| | - Maria Bartolomé
- ABS Mataró Centre, Consorci Sanitari del Maresme, Mataró, 08304 Barcelona, Spain;
| | - Eulogio Pleguezuelos
- Rehabilitation Service, Hospital de Mataró, Consorci Sanitari del Maresme, Mataró, 08304 Barcelona, Spain;
| | - Emili Burdoy
- ABS Argentona, Consorci Sanitari del Maresme, Argentona, 08310 Barcelona, Spain; (M.P.); (E.B.)
- ABS Mataró Centre, Consorci Sanitari del Maresme, Mataró, 08304 Barcelona, Spain;
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Muñoz CX, Johnson EC, Kunces LJ, McKenzie AL, Wininger M, Butts CL, Caldwell A, Seal A, McDermott BP, Vingren J, Colburn AT, Wright SS, Lopez III V, Armstrong LE, Lee EC. Impact of Nutrient Intake on Hydration Biomarkers Following Exercise and Rehydration Using a Clustering-Based Approach. Nutrients 2020; 12:nu12051276. [PMID: 32365848 PMCID: PMC7282025 DOI: 10.3390/nu12051276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/21/2020] [Accepted: 04/27/2020] [Indexed: 12/26/2022] Open
Abstract
We investigated the impact of nutrient intake on hydration biomarkers in cyclists before and after a 161 km ride, including one hour after a 650 mL water bolus consumed post-ride. To control for multicollinearity, we chose a clustering-based, machine learning statistical approach. Five hydration biomarkers (urine color, urine specific gravity, plasma osmolality, plasma copeptin, and body mass change) were configured as raw- and percent change. Linear regressions were used to test for associations between hydration markers and eight predictor terms derived from 19 nutrients merged into a reduced-dimensionality dataset through serial k-means clustering. Most predictor groups showed significant association with at least one hydration biomarker: (1) Glycemic Load + Carbohydrates + Sodium, (2) Protein + Fat + Zinc, (3) Magnesium + Calcium, (4) Pinitol, (5) Caffeine, (6) Fiber + Betaine, and (7) Water; potassium + three polyols, and mannitol + sorbitol showed no significant associations with any hydration biomarker. All five hydration biomarkers were associated with at least one nutrient predictor in at least one configuration. We conclude that in a real-life scenario, some nutrients may serve as mediators of body water, and urine-specific hydration biomarkers may be more responsive to nutrient intake than measures derived from plasma or body mass.
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Affiliation(s)
- Colleen X. Muñoz
- Department of Health Sciences, University of Hartford, West Hartford, CT 06117, USA;
- Correspondence:
| | - Evan C. Johnson
- Division of Kinesiology & Health, University of Wyoming, Laramie, WY 82071, USA;
| | | | | | - Michael Wininger
- Department of Health Sciences, University of Hartford, West Hartford, CT 06117, USA;
- Yale School of Public Health, New Haven, CT 06511, USA
- Department of Veterans Affairs, West Haven, CT 06516, USA
| | - Cory L. Butts
- Department of Health Promotion & Human Performance Weber State University, University of Arkansas, Fayetteville, AR 72701, USA; (C.L.B.); (A.C.); (A.S.); (B.P.M.)
| | - Aaron Caldwell
- Department of Health Promotion & Human Performance Weber State University, University of Arkansas, Fayetteville, AR 72701, USA; (C.L.B.); (A.C.); (A.S.); (B.P.M.)
| | - Adam Seal
- Department of Health Promotion & Human Performance Weber State University, University of Arkansas, Fayetteville, AR 72701, USA; (C.L.B.); (A.C.); (A.S.); (B.P.M.)
- California Polytechnic State University, San Luis Obispo, CA 93407, USA
| | - Brendon P. McDermott
- Department of Health Promotion & Human Performance Weber State University, University of Arkansas, Fayetteville, AR 72701, USA; (C.L.B.); (A.C.); (A.S.); (B.P.M.)
| | - Jakob Vingren
- Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA;
| | - Abigail T. Colburn
- Department of Kinesiology, Human Performance Laboratory, University of Connecticut, Storrs, CT 06269, USA; (A.T.C.); (S.S.W.); (L.E.A.); (E.C.L.)
| | - Skylar S. Wright
- Department of Kinesiology, Human Performance Laboratory, University of Connecticut, Storrs, CT 06269, USA; (A.T.C.); (S.S.W.); (L.E.A.); (E.C.L.)
| | - Virgilio Lopez III
- Department of Kinesiology, Human Performance Laboratory, University of Connecticut, Storrs, CT 06269, USA; (A.T.C.); (S.S.W.); (L.E.A.); (E.C.L.)
| | - Lawrence E. Armstrong
- Department of Kinesiology, Human Performance Laboratory, University of Connecticut, Storrs, CT 06269, USA; (A.T.C.); (S.S.W.); (L.E.A.); (E.C.L.)
| | - Elaine C. Lee
- Department of Kinesiology, Human Performance Laboratory, University of Connecticut, Storrs, CT 06269, USA; (A.T.C.); (S.S.W.); (L.E.A.); (E.C.L.)
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Moghaddam M, Estrada CA, Baghurst T, Jacobson BH. Muscular morphological adaptations of two whole-body high intensity interval training configurations. J Sports Med Phys Fitness 2020; 60:985-991. [PMID: 32343081 DOI: 10.23736/s0022-4707.20.10526-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND High-intensity intermittent training (HIIT) has increased in popularity due to being time-efficient mode of exercise. Previous HIIT studies have mainly focused on percentage of fat loss, fat mass loss, and weight loss. However, enhancing muscle protein synthesis induced by HIIT that results in muscular morphological adaptations is a potential benefit of HIIT. This study compared the effects of two HIIT protocols on muscular morphological adaptations. METHODS Thirty-four recreationally active participants were randomly assigned to 10-5-HIIT and 20-10-HIIT to complete 6 sets of 6 intervals. The 10-5-HIIT and 20-10-HIIT protocols were performed with 10s:5s and 20s:10s exercise-to-rest ratios and provided with 1- and 2-min recovery periods between sets, respectively. Muscle cross-sectional area (mCSA) and echo intensity (EI) of the rectus femoris (RF) and vastus lateralis (VL) were assessed via B-mode ultrasonography before and after intervention. Two-way mixed factorial ANOVAs were used for analyses. RESULTS The 10-5-HIIT and 20-10-HIIT groups significantly (P<0.05) increased RF mCSA (change (Δ)=0.4±0.8 cm2, 8.0%; Δ=0.5±0.8 cm2, 5.5%) and VL mCSA (Δ=1.2±1.6 cm2, 9.0%; Δ=2.20±1.4 cm2, 10.4%), respectively. No significant (P>0.05) change was observed for the EI of the RF and VL. CONCLUSIONS Whole-body HIIT can be a time-efficient exercise modality to elicit muscular morphological adaptations in the RF and VL muscles. The 10-5-HIIT protocol induced benefits comparable to those of the 20-10-HIIT, while it reduced the total exercise time by 50%.
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Vargas-Molina S, Petro JL, Romance R, Kreider RB, Schoenfeld BJ, Bonilla DA, Benítez-Porres J. Effects of a ketogenic diet on body composition and strength in trained women. J Int Soc Sports Nutr 2020; 17:19. [PMID: 32276630 PMCID: PMC7146906 DOI: 10.1186/s12970-020-00348-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/27/2020] [Indexed: 01/07/2023] Open
Abstract
Background The effect of ketogenic diets (KD) on body composition in different populations has been investigated. More recently, some have recommended that athletes adhere to ketogenic diets in order to optimize changes in body composition during training. However, there is less evidence related to trained women. We aimed to evaluate the effect of a KD on body composition and strength in trained women following an eight-week resistance training (RT) program. Methods Twenty-one strength-trained women (27.6 ± 4.0 years; 162.1 ± 6.6 cm; 62.3 ± 7.8 kg; 23.7 ± 2.9 kg·m− 2) were randomly assigned to either a non-KD group (n = 11, NKD) or a KD group (n = 10, KD). Study outcomes included body composition as measured by dual-energy X-ray absorptiometry (DXA), strength levels measured using one maximum repetition (RM) in back squat and bench press (BP), and countermovement jump (CMJ) measured on a force plate. Results A significant reduction in fat mass was observed in KD (− 1.1 ± 1.5 kg; P = 0.042; d = − 0.2) but not in NDK (0.3 ± 0.8 kg; P = 0.225; d = 0.1). No significant changes in fat-free mass were observed in KD (− 0.7 ± 1.7 kg; P = 0.202; d = − 0.1) or NKD (0.7 ± 1.1 kg; P = 0.074; d = 0.2), but absolute changes favored NKD. No significant changes in BP were observed in KD (1.5 ± 4.6 kg; P = 0.329; d = 0.2), although significant changes were noted in the squat and CMJ (5.6 ± 7.6 kg; P = 0.045; d = 0.5 and 2.2 ± 1.7 kg; P = 0.022; d = 0.6, respectively). In contrast, NKD showed significant increases in BP (4.8 ± 1.8; P < 0.01; d = 0.7), squat (15.6 ± 5.4 kg; P = 0.005; d = 1.4) and CMJ (22.0 + 4.2 cm; P = 0.001; d = 0.5). Conclusions Findings indicate that a KD may help to decrease fat mass and maintain fat-free mass after eight 8 weeks of RT in trained-women but is suboptimal for increasing fat-free mass.
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Affiliation(s)
- Salvador Vargas-Molina
- Human Kinetics and Body Composition Laboratory, University of Málaga, Bulevar Louis Pasteur, 25, 29010, Málaga, Spain.,EADE-University of Wales Trinity Saint David, Málaga, Spain
| | - Jorge L Petro
- Research Group in Physical Activity, Sports and Health Sciences (GICAFS), Universidad de Córdoba, Montería, Colombia.,Research Division, DBSS INTERNATIONAL SAS, Bogotá, Colombia
| | - Ramón Romance
- Human Kinetics and Body Composition Laboratory, University of Málaga, Bulevar Louis Pasteur, 25, 29010, Málaga, Spain
| | - Richard B Kreider
- Exercise & Sport Nutrition Lab, Human Clinical Research Facility, Texas A&M University, College Station, TX, USA
| | | | | | - Javier Benítez-Porres
- Human Kinetics and Body Composition Laboratory, University of Málaga, Bulevar Louis Pasteur, 25, 29010, Málaga, Spain.
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Sagayama H, Yamada Y, Ichikawa M, Kondo E, Yasukata J, Tanabe Y, Higaki Y, Takahashi H. Evaluation of fat-free mass hydration in athletes and non-athletes. Eur J Appl Physiol 2020; 120:1179-1188. [PMID: 32239309 DOI: 10.1007/s00421-020-04356-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/21/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate the hydration of fat-free mass (FFM) in athletes and non-athletes. METHODS We analyzed the data of 128 healthy young adults (athletes: 61 men, 36 women; non-athletes: 19 men, 12 women) using the two-component (2C), 3C and 4C models. Under-water weighing or air-displacement plethysmography and deuterium dilution methods were used for estimating body density and total body water, respectively. The bone mineral content (BMC) was determined using whole-body scans by dual-energy X-ray absorptiometry. RESULTS There was no significant difference in FFM hydration between the athletes (men, 72.3 ± 1.3%; women, 71.8 ± 1.3%) and non-athletes (men, 72.1 ± 1.2%; women, 72.2% ± 1.0%) in the 3C model. The total mean FFM hydration (72.1% ± 1.3%) was similar to the corresponding value in the literature (~ 73%). The estimation error of the percentage fat by the 2C vs the 4C model was significantly and highly correlated with hydration (r = 0.96), BMC (r = - 0.70), and total body protein (r = - 0.86) in the 4C model FFM. CONCLUSION Although FFM hydration was similar in athletes and non-athletes, it would be underestimated or overestimated when the 2C model is used for evaluation, and the biological FFM hydration value deviates from the 73% value inter-individually. Despite that this inter-individual variation in FFM hydration is low in terms of between-individual standard deviation (1.3%), the BMC and total body protein differ greatly in athletes, and when it affects FFM hydration, it may also affect the percentage fat measurement in the 2C model. Thus, FFM hydration would not be affected by FFM, percent body fat, or the athletic status.
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Affiliation(s)
- Hiroyuki Sagayama
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan.
| | - Yosuke Yamada
- National Institute of Health and Nutrition, Tokyo, Japan
| | - Mamiko Ichikawa
- Institute of Sports Science and Medicine, Teikyo University, Tokyo, Japan
| | - Emi Kondo
- Japan Institute of Sports Sciences, Tokyo, Japan
| | - Jun Yasukata
- Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan
| | - Yoko Tanabe
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Yasuki Higaki
- Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan
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Abstract
The popularity of physique sports is increasing, yet there are currently few comprehensive nutritional guidelines for these athletes. Physique sport now encompasses more than just a short phase before competition and offseason guidelines have recently been published. Therefore, the goal of this review is to provide an extensive guide for male and female physique athletes in the contest preparation and recovery period. As optimal protein intake is largely related to one’s skeletal muscle mass, current evidence supports a range of 1.8-2.7 g/kg. Furthermore, as a benefit from having adequate carbohydrate to fuel performance and activity, low-end fat intake during contest preparation of 10-25% of calories allows for what calories remain in the “energy budget” to come from carbohydrate to mitigate the negative impact of energy restriction and weight loss on training performance. For nutrient timing, we recommend consuming four or five protein boluses per day with one consumed near training and one prior to sleep. During competition periods, slower rates of weight loss (≤0.5% of body mass per week) are preferable for attenuating the loss of fat-free mass with the use of intermittent energy restriction strategies, such as diet breaks and refeeds, being possibly beneficial. Additionally, physiological and psychological factors are covered, and potential best-practice guidelines are provided for disordered eating and body image concerns since physique athletes present with higher incidences of these issues, which may be potentially exacerbated by certain traditional physique practices. We also review common peaking practices, and the critical transition to the post-competition period.
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Valsdottir TD, Henriksen C, Odden N, Nellemann B, Jeppesen PB, Hisdal J, Westerberg AC, Jensen J. Effect of a Low-Carbohydrate High-Fat Diet and a Single Bout of Exercise on Glucose Tolerance, Lipid Profile and Endothelial Function in Normal Weight Young Healthy Females. Front Physiol 2019; 10:1499. [PMID: 31920704 PMCID: PMC6931312 DOI: 10.3389/fphys.2019.01499] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 11/25/2019] [Indexed: 01/07/2023] Open
Abstract
Low-carbohydrate-high-fat (LCHF) diets are efficient for weight loss, and are also used by healthy people to maintain bodyweight. The main aim of this study was to investigate the effect of 3-week energy-balanced LCHF-diet, with >75 percentage energy (E%) from fat, on glucose tolerance and lipid profile in normal weight, young, healthy women. The second aim of the study was to investigate if a bout of exercise would prevent any negative effect of LCHF-diet on glucose tolerance. Seventeen females participated, age 23.5 ± 0.5 years; body mass index 21.0 ± 0.4 kg/m2, with a mean dietary intake of 78 ± 1 E% fat, 19 ± 1 E% protein and 3 ± 0 E% carbohydrates. Measurements were performed at baseline and post-intervention. Fasting glucose decreased from 4.7 ± 0.1 to 4.4 mmol/L (p < 0.001) during the dietary intervention whereas fasting insulin was unaffected. Glucose area under the curve (AUC) and insulin AUC did not change during an OGTT after the intervention. Before the intervention, a bout of aerobic exercise reduced fasting glucose (4.4 ± 0.1 mmol/L, p < 0.001) and glucose AUC (739 ± 41 to 661 ± 25, p = 0.008) during OGTT the following morning. After the intervention, exercise did not reduce fasting glucose the following morning, and glucose AUC during an OGTT increased compared to the day before (789 ± 43 to 889 ± 40 mmol/L∙120min–1, p = 0.001). AUC for insulin was unaffected. The dietary intervention increased total cholesterol (p < 0.001), low-density lipoprotein (p ≤ 0.001), high-density lipoprotein (p = 0.011), triglycerides (p = 0.035), and free fatty acids (p = 0.021). In conclusion, 3-week LCHF-diet reduced fasting glucose, while glucose tolerance was unaffected. A bout of exercise post-intervention did not decrease AUC glucose as it did at baseline. Total cholesterol increased, mainly due to increments in low-density lipoprotein. LCHF-diets should be further evaluated and carefully considered for healthy individuals.
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Affiliation(s)
- Thorhildur Ditta Valsdottir
- Department of Medicine, Atlantis Medical University College, Oslo, Norway.,Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Christine Henriksen
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Nancy Odden
- Department of Nutrition, Atlantis Medical University College, Oslo, Norway
| | - Birgitte Nellemann
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Per B Jeppesen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jonny Hisdal
- Oslo Vascular Center, Department of Vascular Surgery, Oslo University Hospital, Oslo, Norway
| | - Ane C Westerberg
- Department of Nutrition, Atlantis Medical University College, Oslo, Norway.,Institute of Health Sciences, Kristiania University College, Oslo, Norway
| | - Jørgen Jensen
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
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Fazzino TL, Serwatka C, Schneider H, Sullivan D. A systematic review of the methodology used to study weight change among young adults attending college. Eat Behav 2019; 35:101333. [PMID: 31491664 DOI: 10.1016/j.eatbeh.2019.101333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 07/29/2019] [Accepted: 08/22/2019] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Young adulthood is a sensitive developmental period that is high-risk for weight gain. Ample research has focused on weight gain among college students; however meta-analyses report <2 kg pooled estimates of weight gain, which is in the range of normal weight fluctuation, and there is disagreement in the literature regarding common predictors of weight gain. These limitations pose a major barrier to targeted obesity prevention efforts. The present study reviewed the literature assessing college weight gain with a focus on three methodological factors that could contribute to variability in the literature: 1) use of an evidence-supported definition of weight gain (>2 kg or ≥3%); 2) weight measurement protocols; and 3) including weight/BMI in analyses of predictors of weight change. METHODS Three databases were systematically searched. Studies were included in the review if the primary goal was to determine magnitude of weight change and/or test predictors of weight change during the academic year, and they reported weight at 2+ time points. RESULTS A total of 81 studies were included in the review. Most studies (90%; 73/81) did not use an evidence-supported definition of weight gain. Studies that used an evidence-supported definition reported estimates of gain among students who gained weight to be beyond the range of normal weight fluctuation (4.0-7.5 kg), and occurred in a subset (<32%) of participants. Studies that did not use an evidence-supported definition reported weight gain to be 2.0-4.5 kg, and occurred in the majority >50% of students. Most studies that measured height and weight (71%; 42/59) did not use a fasting protocol and the majority (63%; 37/59) did not conduct measurements at the same time of day. A higher percentage of studies that used a standardized measurement protocol reported weight change >2 kg (44% vs 20%). A lower percentage of studies that used a standardized measurement protocol had substantial variability in weight change estimates (50% vs 69%). The majority of studies that tested predictors of weight gain (74%; 42/57) included weight/BMI as a covariate in analyses. CONCLUSIONS The body of literature examining weight change among college students suffers from limitations that may have contributed to overestimations in the percent of students who gain weight, and simultaneous underestimations of the magnitude of weight gain among those who gain weight. Weight gain may be limited to approximately 30% of students in a sample, and weight gain among this subset of students may be substantial (>4 kg). Going forward, use of both an evidence-supported weight gain definition and fasting measurement protocol will likely enhance accuracy in characterizing weight gain among college students, as well as improve researchers' ability to detect important predictors of weight gain.
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Affiliation(s)
- Tera L Fazzino
- Department of Psychology, University of Kansas, United States of America; Cofrin Logan Center for Addiction Research and Treatment, University of Kansas, United States of America.
| | - Catherine Serwatka
- Department of Psychology, University of Kansas, United States of America; Cofrin Logan Center for Addiction Research and Treatment, University of Kansas, United States of America
| | - Heather Schneider
- Department of Psychology, University of Kansas, United States of America; Cofrin Logan Center for Addiction Research and Treatment, University of Kansas, United States of America
| | - Debra Sullivan
- Department of Nutrition and Dietetics, University of Kansas Medical Center, United States of America
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Abstract
Ketogenic diet (KD) is a nutritional regimen characterized by a high-fat and an adequate protein content and a very low carbohydrate level (less than 20 g per day or 5% of total daily energy intake). The insufficient level of carbohydrates forces the body to primarily use fat instead of sugar as a fuel source. Due to its characteristic, KD has often been used to treat metabolic disorders, obesity, cardiovascular disease, and type 2 diabetes. Skeletal muscle constitutes 40% of total body mass and is one of the major sites of glucose disposal. KD is a well-defined approach to induce weight loss, with its role in muscle adaptation and muscle hypertrophy less understood. Considering this lack of knowledge, the aim of this review was to examine the scientific evidence about the effects of KD on muscle hypertrophy. We first described the mechanisms of muscle hypertrophy per se, and secondly, we discussed the characteristics and the metabolic function of KD. Ultimately, we provided the potential mechanism that could explain the influence of KD on skeletal muscle hypertrophy.
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The Role of Water Homeostasis in Muscle Function and Frailty: A Review. Nutrients 2019; 11:nu11081857. [PMID: 31405072 PMCID: PMC6723611 DOI: 10.3390/nu11081857] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 07/31/2019] [Accepted: 08/07/2019] [Indexed: 02/07/2023] Open
Abstract
Water, the main component of the body, is distributed in the extracellular and intracellular compartments. Water exchange between these compartments is mainly governed by osmotic pressure. Extracellular water osmolarity must remain within very narrow limits to be compatible with life. Older adults lose the thirst sensation and the ability to concentrate urine, and this favours increased extracellular osmolarity (hyperosmotic stress). This situation, in turn, leads to cell dehydration, which has severe consequences for the intracellular protein structure and function and, ultimately, results in cell damage. Moreover, the fact that water determines cell volume may act as a metabolic signal, with cell swelling acting as an anabolic signal and cell shrinkage acting as a catabolic signal. Ageing also leads to a progressive loss in muscle mass and strength. Muscle strength is the main determinant of functional capacity, and, in elderly people, depends more on muscle quality than on muscle quantity (or muscle mass). Intracellular water content in lean mass has been related to muscle strength, functional capacity, and frailty risk, and has been proposed as an indicator of muscle quality and cell hydration. This review aims to assess the role of hyperosmotic stress and cell dehydration on muscle function and frailty.
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Lopez P, Pinto MD, Pinto RS. Does Rest Time before Ultrasonography Imaging Affect Quadriceps Femoris Muscle Thickness, Cross-Sectional Area and Echo Intensity Measurements? ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:612-616. [PMID: 30471782 DOI: 10.1016/j.ultrasmedbio.2018.10.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 09/27/2018] [Accepted: 10/05/2018] [Indexed: 06/09/2023]
Abstract
In the work described here, our aim was to determine, in an elderly population, changes in muscle thickness (MT), cross-sectional area (CSA) and echo intensity (EI) of the quadriceps muscles at four time points (0, 5, 10 and 15 min; i.e., T0, T5, T10 and T15, respectively) after changing from a standing to supine position. Twenty-one elderly participants (14 men: 68.1 ± 4.6 y; 8 women: 66.8 ± 4.1 y) were evaluated at four time points. Rectus femoris CSA (RFCSA), MT and EI of the quadriceps femoris (QF) muscles were assessed. EI significantly increased from T0 to T5, T10 and T15 (p < 0.001), whereas no differences were observed between T5 and T15 in the rectus femoris (RFEI), vastus intermedius (VIEI) and quadriceps femoris (QFEI). No differences were observed between any time points in the RFCSA and MT of QF muscles. In summary, these results suggest that periods >5 min are not necessary to obtain consistent MT and EI measurements of quadriceps femoris muscles in the elderly population.
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Affiliation(s)
- Pedro Lopez
- Exercise Research Laboratory, Physical Education, Physiotherapy and Dance School, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
| | - Matheus Daros Pinto
- Centre for Exercise and Sport Science Research (CESSR), School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Ronei Silveira Pinto
- Exercise Research Laboratory, Physical Education, Physiotherapy and Dance School, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Hornsby WG, Gentles JA, Haff GG, Stone MH, Buckner SL, Dankel SJ, Bell ZW, Abe T, Loenneke JP. What is the Impact of Muscle Hypertrophy on Strength and Sport Performance? Strength Cond J 2018. [DOI: 10.1519/ssc.0000000000000432] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Protein synthesis signaling in skeletal muscle is refractory to whey protein ingestion during a severe energy deficit evoked by prolonged exercise and caloric restriction. Int J Obes (Lond) 2018; 43:872-882. [PMID: 30242237 DOI: 10.1038/s41366-018-0174-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/24/2018] [Accepted: 06/24/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Exercise and protein ingestion preserve muscle mass during moderate energy deficits. OBJECTIVE To determine the molecular mechanisms by which exercise and protein ingestion may spare muscle mass during severe energy deficit (5500 kcal/day). DESIGN Fifteen overweight, but otherwise healthy men, underwent a pre-test (PRE), caloric restriction (3.2 kcals/kg body weight/day) + exercise (45 min one-arm cranking + 8 h walking) for 4 days (CRE), followed by a control diet (CD) for 3 days, with a caloric content similar to pre-intervention while exercise was reduced to less than 10,000 steps per day. During CRE, participants ingested either whey protein (PRO, n = 8) or sucrose (SU, n = 7) (0.8 g/kg body weight/day). Muscle biopsies were obtained from the trained and untrained deltoid, and vastus lateralis. RESULTS Following CRE and CD, serum concentrations of leptin, insulin, and testosterone were reduced, whereas cortisol and the catabolic index (cortisol/total testosterone) increased. The Akt/mTor/p70S6K pathway and total eIF2α were unchanged, while total 4E-BP1 and Thr37/464E-BP1 were higher. After CRE, plasma BCAA and EAA were elevated, with a greater response in PRO group, and total GSK3β, pSer9GSK3β, pSer51eIF2α, and pSer51eIF2α/total eIF2α were reduced, with a greater response of pSer9GSK3β in the PRO group. The changes in signaling were associated with the changes in leptin, insulin, amino acids, cortisol, cortisol/total testosterone, and lean mass. CONCLUSIONS During severe energy deficit, pSer9GSK3β levels are reduced and human skeletal muscle becomes refractory to the anabolic effects of whey protein ingestion, regardless of contractile activity. These effects are associated with the changes in lean mass and serum insulin, testosterone, and cortisol concentrations.
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Reipert S, Goldammer H, Richardson C, Goldberg MW, Hawkins TJ, Hollergschwandtner E, Kaufmann WA, Antreich S, Stierhof YD. Agitation Modules: Flexible Means to Accelerate Automated Freeze Substitution. J Histochem Cytochem 2018; 66:903-921. [PMID: 29969056 DOI: 10.1369/0022155418786698] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
For ultrafast fixation of biological samples to avoid artifacts, high-pressure freezing (HPF) followed by freeze substitution (FS) is preferred over chemical fixation at room temperature. After HPF, samples are maintained at low temperature during dehydration and fixation, while avoiding damaging recrystallization. This is a notoriously slow process. McDonald and Webb demonstrated, in 2011, that sample agitation during FS dramatically reduces the necessary time. Then, in 2015, we (H.G. and S.R.) introduced an agitation module into the cryochamber of an automated FS unit and demonstrated that the preparation of algae could be shortened from days to a couple of hours. We argued that variability in the processing, reproducibility, and safety issues are better addressed using automated FS units. For dissemination, we started low-cost manufacturing of agitation modules for two of the most widely used FS units, the Automatic Freeze Substitution Systems, AFS(1) and AFS2, from Leica Microsystems, using three dimensional (3D)-printing of the major components. To test them, several labs independently used the modules on a wide variety of specimens that had previously been processed by manual agitation, or without agitation. We demonstrate that automated processing with sample agitation saves time, increases flexibility with respect to sample requirements and protocols, and produces data of at least as good quality as other approaches.
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Affiliation(s)
- Siegfried Reipert
- Core Facility Cell Imaging and Ultrastructure Research, University of Vienna, Vienna, Austria
| | - Helmuth Goldammer
- Core Facility Cell Imaging and Ultrastructure Research, University of Vienna, Vienna, Austria
| | | | - Martin W Goldberg
- Department of Biosciences, Durham University, Durham, United Kingdom
| | - Timothy J Hawkins
- Department of Biosciences, Durham University, Durham, United Kingdom
| | | | - Walter A Kaufmann
- Electron Microscopy Facility, Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Sebastian Antreich
- Core Facility Cell Imaging and Ultrastructure Research, University of Vienna, Vienna, Austria
| | - York-Dieter Stierhof
- Center for Plant Molecular Biology (ZMBP), Microscopy, University of Tübingen, Tübingen, Germany
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Abstract
The ability of athletes to train day after day depends in large part on adequate restoration of muscle glycogen stores, a process that requires the consumption of sufficient dietary carbohydrates and ample time. Providing effective guidance to athletes and others wishing to enhance training adaptations and improve performance requires an understanding of the normal variations in muscle glycogen content in response to training and diet; the time required for adequate restoration of glycogen stores; the influence of the amount, type, and timing of carbohydrate intake on glycogen resynthesis; and the impact of other nutrients on glycogenesis. This review highlights the practical implications of the latest research related to glycogen metabolism in physically active individuals to help sports dietitians, coaches, personal trainers, and other sports health professionals gain a fundamental understanding of glycogen metabolism, as well as related practical applications for enhancing training adaptations and preparing for competition.
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Affiliation(s)
- Bob Murray
- Sports Science Insights, LLC, Crystal Lake, Illinois, USA
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42
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Bhutani S, Kahn E, Tasali E, Schoeller DA. Composition of two-week change in body weight under unrestricted free-living conditions. Physiol Rep 2018; 5:5/13/e13336. [PMID: 28676555 PMCID: PMC5506524 DOI: 10.14814/phy2.13336] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 05/29/2017] [Indexed: 11/24/2022] Open
Abstract
The composition of weight change has a large impact on energy balance calculations. Composition of long-term weight change interventions is well-documented, but information on short-term weight change under unrestricted free-living conditions is limited. The composition and energy density of the changes in body weight during 2-week free-living conditions were analyzed in adults from two cohorts: cohort 1 (n = 24) included participants from the reproducibility subset of the Observing Protein and Energy Nutrition study; cohort 2 (n = 22) included participants who were studied under free-living conditions in an ongoing study in the Chicago area. Change in body weight, total body water (TBW) by stable isotope dilution (cohort 1), and fat mass (FM) and fat-free mass (FFM) by serial DXA (cohort 2) were measured. To determine the fractional composition of the change in body weight we analyzed the linear associations between changes in body weight and changes in body composition. In the combined dataset, the average change in body weight (0.26 ± 1.2 kg) was consistent with being in energy balance. Average change in body weight was associated with the change in TBW (P < 0.0001) in cohort 1 and the change in FFM (P = 0.0002) in cohort 2. A unit change in body weight was composed of 84% change in FFM in the combined dataset indicating that 2-week fluctuation in body weight is largely composed of FFM The energy density of 1-3 kg short-term changes in body weight averaged 2380 kcal/kg.
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Affiliation(s)
- Surabhi Bhutani
- Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin .,Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Eva Kahn
- Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Esra Tasali
- Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Dale A Schoeller
- Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin
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43
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Affiliation(s)
| | - Roger Harris
- Formerly University of Chichester, Chichester, UK.
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44
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Bone JL, Ross ML, Tomcik KA, Jeacocke NA, Hopkins WG, Burke LM. Manipulation of Muscle Creatine and Glycogen Changes Dual X-ray Absorptiometry Estimates of Body Composition. Med Sci Sports Exerc 2017; 49:1029-1035. [PMID: 28410328 DOI: 10.1249/mss.0000000000001174] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Standardizing a dual x-ray absorptiometry (DXA) protocol is thought to provide a reliable measurement of body composition. PURPOSE We investigated the effects of manipulating muscle glycogen and creatine content independently and additively on DXA estimates of lean mass. METHOD Eighteen well-trained male cyclists undertook a parallel group application of creatine loading (n = 9) (20 g·d for 5 d loading; 3 g·d maintenance) or placebo (n = 9) with crossover application of glycogen loading (12 v 6 g·kg BM per day for 48 h) as part of a larger study involving a glycogen-depleting exercise protocol. Body composition, total body water, muscle glycogen and creatine content were assessed via DXA, bioelectrical impedance spectroscopy and standard biopsy techniques. Changes in the mean were assessed using the following effect-size scale: >0.2 small, >0.6, moderate, >1.2 large and compared with the threshold for the smallest worthwhile effect of the treatment. RESULTS Glycogen loading, both with and without creatine loading, resulted in substantial increases in estimates of lean body mass (mean ± SD; 3.0% ± 0.7% and 2.0% ± 0.9%) and leg lean mass (3.1% ± 1.8% and 2.6% ± 1.0%) respectively. A substantial decrease in leg lean mass was observed after the glycogen depleting condition (-1.4% ± 1.6%). Total body water showed substantial increases after glycogen loading (2.3% ± 2.3%), creatine loading (1.4% ± 1.9%) and the combined treatment (2.3% ± 1.1%). CONCLUSIONS Changes in muscle metabolites and water content alter DXA estimates of lean mass during periods in which minimal change in muscle protein mass is likely. This information needs to be considered in interpreting the results of DXA-derived estimates of body composition in athletes.
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Affiliation(s)
- Julia L Bone
- 1Sports Nutrition, Australian Institute of Sport, Canberra ACT, AUSTRALIA; 2Centre for Exercise and Nutrition, Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC, AUSTRALIA; and 3College of Sport and Exercise Science, Victoria University, Melbourne, VIC, AUSTRALIA
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45
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Blue MNM, Smith-Ryan AE, Trexler ET, Hirsch KR. The effects of high intensity interval training on muscle size and quality in overweight and obese adults. J Sci Med Sport 2017. [PMID: 28647284 DOI: 10.1016/j.jsams.2017.06.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVES Despite growing popularity of high intensity interval training (HIIT) for improving health and fitness, limited data exist identifying the effects of HIIT on muscle characteristics. The purpose of the current study was to investigate the effects of a 3-week HIIT intervention on muscle size and quality in overweight and obese men and women. DESIGN Randomized controlled trial. METHODS Forty-four overweight and obese men and women (mean±SD; age: 35.4±12.3years; height: 174.9±9.7cm; weight: 94.6±17.0kg; %fat: 32.7±6.5%) completed the current study. During baseline and post testing, muscle cross sectional area (mCSA) and echo intensity (EI) were determined from a panoramic scan of the vastus lateralis obtained by B-mode ultrasonography. Body composition variables were measured using dual energy X-ray absorptiometry. Participants were randomized into either a 1:1 work-to-rest ratio HIIT group (SIT; n=16), a 2:1 work-to-rest ratio HIIT group (LIT; n=19), or control (CON; n=9). HIIT participants performed five, 2-min bouts (LIT) or 10, 1-min bouts (SIT) at 85-100% VO2peak for 9 sessions over three weeks. RESULTS Analysis of covariance demonstrated a significant increase in mCSA for SIT (p=0.038; change (Δ)=3.17±3.36cm2) compared to CON (Δ=-0.34±2.36cm2). There was no significant difference in EI across groups (p=0.672). CONCLUSIONS HIIT may be an effective exercise modality to influence muscle size in overweight and obese individuals. Future studies should investigate muscle characteristics and remodeling in an overweight population following interventions of longer duration and varying work-to-rest protocols.
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Affiliation(s)
- Malia N M Blue
- Applied Physiology Laboratory, Department of Exercise and Sport Science, University of North Carolina, USA; Human Movement Science Curriculum, Department of Allied Health Science, University of North Carolina, USA
| | - Abbie E Smith-Ryan
- Applied Physiology Laboratory, Department of Exercise and Sport Science, University of North Carolina, USA; Human Movement Science Curriculum, Department of Allied Health Science, University of North Carolina, USA.
| | - Eric T Trexler
- Applied Physiology Laboratory, Department of Exercise and Sport Science, University of North Carolina, USA; Human Movement Science Curriculum, Department of Allied Health Science, University of North Carolina, USA
| | - Katie R Hirsch
- Applied Physiology Laboratory, Department of Exercise and Sport Science, University of North Carolina, USA; Human Movement Science Curriculum, Department of Allied Health Science, University of North Carolina, USA
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Mora-Rodríguez R, Sanchez-Roncero A, Fernández-Elías VE, Guadalupe-Grau A, Ortega JF, Dela F, Helge JW. Aerobic Exercise Training Increases Muscle Water Content in Obese Middle-Age Men. Med Sci Sports Exerc 2017; 48:822-8. [PMID: 26694843 DOI: 10.1249/mss.0000000000000848] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The objective of this study is to determine whether muscle water content (H2Omuscle) expands with training in deconditioned middle-age men and the effects of this expansion in other muscle metabolites. METHODS Eighteen obese (BMI = 33 ± 3 kg⁻¹·m⁻²) untrained (V˙O2peak = 29 ± 7 mL⁻¹·kg⁻¹·min⁻¹) metabolic syndrome men completed a 4-month aerobic cycling training program. Vastus lateralis muscle biopsies were collected before and 72 h after the completion of the last training bout. Water content, total protein, glycogen concentration, and citrate synthase activity were measured in biopsy tissue. Body composition was assessed using dual-energy X-ray absorptiometry, and cardiometabolic fitness was measured during an incremental cycling test. RESULTS Body weight and fat mass were reduced -1.9% and -5.4%, respectively (P < 0.05), whereas leg fat free mass increased with training (1.8%, P = 0.023). Cardiorespiratory fitness (i.e., V˙O2peak), exercise maximal fat oxidation (i.e., FOmax), and maximal cycling power (i.e., Wmax) improved with training (11%, 33%, and 10%, respectively; P < 0.05). After 4 months of training, H2Omuscle increased from 783 ± 18 to 799 ± 24 g·kg⁻¹ wet weight (ww) (2%, P = 0.011), whereas muscle protein concentration decreased 11% (145 ± 15 to 129 ± 13 g·kg⁻¹ ww, P = 0.007). Citrate synthase activity (proxy for mitochondrial density) increased by 31% (17 ± 5 to 22 ± 5 mmol·min⁻¹·kg⁻¹ ww, P = 0.024). Muscle glycogen concentration increased by 14% (22 ± 7 to 25 ± 7 g·kg⁻¹ ww) although without reaching statistical significance when expressed as per kilogram of wet weight (P = 0.15). CONCLUSIONS Our findings suggest that aerobic cycling training increases quadriceps muscle water although reduces muscle protein concentration in obese metabolic syndrome men. Reduced protein concentration coexists with increased leg lean mass suggestive of a water dilution effect that however does not impair increased cycling leg power with training.
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Affiliation(s)
- Ricardo Mora-Rodríguez
- 1Exercise Physiology Laboratory at Toledo, University of Castilla-La Mancha, Toledo, SPAIN; and 2Xlab, Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, Copenhagen, DENMARK
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Jenkins NDM. Are Resistance Training-Mediated Decreases in Ultrasound Echo Intensity Caused by Changes in Muscle Composition, or Is There an Alternative Explanation? ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:3050-3051. [PMID: 27590097 DOI: 10.1016/j.ultrasmedbio.2016.07.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 07/09/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Nathaniel D M Jenkins
- Department of Health and Human Performance, Applied Neuromuscular Physiology Laboratory, Oklahoma State University, Stillwater, Oklahoma, USA.
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Che Jusoh MR, Stannard SR, Mündel T. Sago supplementation for exercise performed in a thermally stressful environment: Rationale, efficacy and opportunity. Temperature (Austin) 2016; 3:384-393. [PMID: 28349080 PMCID: PMC5079226 DOI: 10.1080/23328940.2016.1211072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 06/30/2016] [Accepted: 07/02/2016] [Indexed: 12/04/2022] Open
Abstract
Sago (Metroxylin sagu), a carbohydrate (CHO) based dietary staple of Southeast Asia is easily digestible and quickly absorbed, and thus has potential to be prescribed as an affordable pre-and post-exercise food in this part of the world. Compared to other CHO staples, research into the physiological response to sago ingestion is sparse, and only a few recent studies have investigated its value before, during, and after exercise. The purpose of this review is to describe the published literature pertaining to sago, particularly as a supplement in the peri-exercise period, and suggest further avenues of research, principally in an environment/climate which would be experienced in Southeast Asia i.e. hot/humid.
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Affiliation(s)
| | - Stephen R. Stannard
- School of Sport and Exercise, Massey University, Palmerston North, New Zealand
| | - Toby Mündel
- School of Sport and Exercise, Massey University, Palmerston North, New Zealand
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