1
|
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.
Collapse
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
| |
Collapse
|
2
|
Baghdassarian HM, Lewis NE. Resource allocation in mammalian systems. Biotechnol Adv 2024; 71:108305. [PMID: 38215956 PMCID: PMC11182366 DOI: 10.1016/j.biotechadv.2023.108305] [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: 08/03/2023] [Revised: 12/17/2023] [Accepted: 12/18/2023] [Indexed: 01/14/2024]
Abstract
Cells execute biological functions to support phenotypes such as growth, migration, and secretion. Complementarily, each function of a cell has resource costs that constrain phenotype. Resource allocation by a cell allows it to manage these costs and optimize their phenotypes. In fact, the management of resource constraints (e.g., nutrient availability, bioenergetic capacity, and macromolecular machinery production) shape activity and ultimately impact phenotype. In mammalian systems, quantification of resource allocation provides important insights into higher-order multicellular functions; it shapes intercellular interactions and relays environmental cues for tissues to coordinate individual cells to overcome resource constraints and achieve population-level behavior. Furthermore, these constraints, objectives, and phenotypes are context-dependent, with cells adapting their behavior according to their microenvironment, resulting in distinct steady-states. This review will highlight the biological insights gained from probing resource allocation in mammalian cells and tissues.
Collapse
Affiliation(s)
- Hratch M Baghdassarian
- Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nathan E Lewis
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
3
|
Cho W, Jung H, Hong S, Yang HI, Park DH, Suh SH, Lee DH, Choe YS, Kim JY, Lee W, Jeon JY. The effect of a short-term ketogenic diet on exercise efficiency during graded exercise in healthy adults. J Int Soc Sports Nutr 2023; 20:2264278. [PMID: 37791478 PMCID: PMC10552596 DOI: 10.1080/15502783.2023.2264278] [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: 11/03/2022] [Accepted: 09/22/2023] [Indexed: 10/05/2023] Open
Abstract
OBJECTIVE We examined the effects of short-term KD on exercise efficiency and hormonal response during and after the graded exercise testing. METHODS Fourteen untrained healthy adults (8 males, 6 females, age 26.4 ± 3.1 [SD] years; BMI 24.8 ± 4.6 kg/m2; peak VO2max 54.0 ± 5.8 ml/kg FFM/min) completed 3-days of a mixed diet (MD) followed by another 3-days of KD after 3-days of washout period. Upon completion of each diet arm, participants underwent graded exercise testing with low- (LIE; 40% of VO2max), moderate- (MIE; 55%), and high-intensity exercise (HIE; 70%). Exercise efficiency was calculated as work done (kcal/min)/energy expenditure (kcal/min). RESULTS Fat oxidation during the recovery period was higher in KD vs. MD. Despite identical workload during HIE, participants after having KD vs. MD showed higher energy expenditure and lower exercise efficiency (10.1 ± 0.7 vs. 12.5 ± 0.3%, p < .01). After KD, free fatty acid (FFA) concentrations were higher during MIE and recovery vs. resting, and beta-hydroxybutylate (BOHB) was lower at HIE vs. resting. Cortisol concentrations after KD was higher during recovery vs. resting, with no significant changes during graded exercise testing after MD. CONCLUSIONS Our data suggest that short-term KD is favorable to fat metabolism leading increased circulating FFA and BOHB during LIE to MIE. However, it is notable that KD may cause 1) exercise inefficiency manifested by increased energy expenditure and 2) elevated exercise stress during HIE and recovery. Trial registration: KCT0005172, International Clinical Trials Registry Platform.
Collapse
Affiliation(s)
- Wonhee Cho
- Syracuse University, Department of Exercise Science, David B. Falk College of Sport and Human Dynamics, Syracuse, NY, USA
- Yonsei University, Department of Sport Industries, Seoul, South Korea
| | - Hwaebong Jung
- Yonsei University, Department of Materials Science and Engineering, Seoul, South Korea
| | - Sunghyun Hong
- Yonsei University, Department of Sport Industries, Seoul, South Korea
| | - Hyuk In Yang
- Yonsei University, Department of Sport Industries, Seoul, South Korea
| | - Dong-Hyuk Park
- Yonsei University, Department of Sport Industries, Seoul, South Korea
| | - Sang-Hoon Suh
- Yonsei University, Department of Physical Education, Seoul, South Korea
| | - Dong Hoon Lee
- Yonsei University, Department of Sport Industries, Seoul, South Korea
- Harvard T.H. Chan School of Public Health, Department of Nutrition, Boston, MA, USA
- Nanyang Technological University, Lee Kong Chian School of Medicine, Nanyang, Singapore
| | | | - Joon Young Kim
- Syracuse University, Department of Exercise Science, David B. Falk College of Sport and Human Dynamics, Syracuse, NY, USA
| | - Wooyoung Lee
- Yonsei University, Department of Materials Science and Engineering, Seoul, South Korea
| | - Justin Y. Jeon
- Yonsei University, Department of Sport Industries, Seoul, South Korea
- Yonsei University College of Medicine, Cancer Prevention Center, Yonsei Cancer Center, Seoul, South Korea
- Yonsei University, Exercise Medicine Center for Diabetes and Cancer Patients, ICONS, Seoul, South Korea
| |
Collapse
|
4
|
Lowder J, Fallah S, Venditti C, Musa-Veloso K, Kotlov V. An open-label, acute clinical trial in adults to assess ketone levels, gastrointestinal tolerability, and sleepiness following consumption of ( R)-1,3-butanediol (Avela™). Front Physiol 2023; 14:1195702. [PMID: 37457035 PMCID: PMC10338333 DOI: 10.3389/fphys.2023.1195702] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 06/09/2023] [Indexed: 07/18/2023] Open
Abstract
Introduction: A study was undertaken to determine the acute effects of a beverage made with Avela™ (R)-1,3-butanediol, on blood beta-hydroxybutyrate (BHB) levels (using the Keto-Mojo monitor), gastrointestinal (GI) tolerability (using the modified visual analogue scale GI Symptoms Tool), and sleepiness (using the Stanford Sleepiness Scale). Methods: Following a 12-h overnight fast, 26 healthy adults consumed one beverage containing 11.5 g of (R)-1,3-butanediol at each of 0, 30, and 60 min, culminating in a total intake of 34.5 g of (R)-1,3-butanediol. Blood BHB levels, GI tolerability, and sleepiness were assessed at baseline (0 min), and at 30, 60, 90, 120, 180, 240, and 300 min. At 240 min, a protein bar was consumed. Results: The mean (±SD) BHB fasting baseline level, maximal concentration, time at maximal concentration, and incremental area under the curve over 300 min were 0.23 ± 0.21 mmol/L, 2.10 ± 0.97 mmol/L, 133.85 ± 57.07 min, and 376.73 ± 156.76 mmol/L*min, respectively. BHB levels at each time point were significantly increased relative to baseline. In females, BHB Tmax was significantly greater (p = 0.046), and BHB iAUC0-300 min nearly significantly greater (p = 0.06) than in males. Discussion: The beverage formulated with Avela™ had no impact on sleepiness and was generally well-tolerated, with no or mild GI symptoms reported in most participants. Mild headaches were reported as an adverse event by five participants and judged possibly related to the study product in two of the participants.
Collapse
Affiliation(s)
- James Lowder
- Principal Investigator, Impact Science Alliance, San Diego, CA, United States
| | | | | | | | - Vassili Kotlov
- Study Coordinator, Impact Science Alliance, San Diego, CA, United States
| |
Collapse
|
5
|
Ward KE, Ramsay J, Vu BJ. A Case of Severe Metabolic Acidosis in the Setting of a Strict Ketogenic Diet. Cureus 2023; 15:e38741. [PMID: 37303440 PMCID: PMC10247339 DOI: 10.7759/cureus.38741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2023] [Indexed: 06/13/2023] Open
Abstract
Patients with metabolic acidosis often present with obscure, multifactorial etiologies, making efficient diagnosis and treatment key to preventing poor clinical outcomes. This case report describes a patient with severe metabolic acidosis in which the underlying cause was not immediately apparent. After a thorough work-up and history taking, the patient's strict ketogenic diet was identified as the most likely source of his illness. Over multiple days, the patient improved as he resumed a normal diet and was treated for refeeding syndrome. This case highlights the importance of taking a comprehensive social and diet history when assessing a patient with metabolic acidosis. It also highlights the need for physicians to understand and be ready to counsel on the possible effects of fad diets, such as the ketogenic diet.
Collapse
Affiliation(s)
- Kerrie E Ward
- Internal Medicine, University of California Irvine, Orange, USA
| | - Jay Ramsay
- Internal Medicine, University of California Irvine, Orange, USA
| | - Bao Joseph Vu
- Internal Medicine, Veterans Affairs Long Beach Healthcare System, Long Beach, USA
- Internal Medicine, University of California Irvine, Orange, USA
| |
Collapse
|
6
|
Defeudis G, Rossini M, Khazrai YM, Pipicelli AMV, Brucoli G, Veneziano M, Strollo F, Bellia A, Bitterman O, Lauro D, Mora D, Santarelli E. The gut microbiome as possible mediator of the beneficial effects of very low calorie ketogenic diet on type 2 diabetes and obesity: a narrative review. Eat Weight Disord 2022; 27:2339-2346. [PMID: 35773554 DOI: 10.1007/s40519-022-01434-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 06/11/2022] [Indexed: 10/17/2022] Open
Abstract
Several studies have shown a strong correlation between the different types of diets and gut microbiota composition on glycemia and weight loss. In this direction, low-carbohydrate and ketogenic diets have gained popularity, despite studies published so far leading to controversial results on subjects with diabetes. In this narrative review, firstly, we aimed to analyze the role of very-low-calorie ketogenic diets (VLCKDs) in type 2 diabetes (T2DM) and obesity management. Secondly, in this context, we focused attention on gut microbiota as a function of VLCKD, particularly in T2DM and obesity treatment. Finally, we reported all this evidence to underline the importance of gut microbiota to exalt new nutritional strategies for "tailor-made" management, treatment, and rehabilitation in subjects with T2DM and obesity, even with diabetic complications. In conclusion, this narrative review outlined the beneficial impact of VLCKD on gut microbiota even in subjects with T2DM and obesity, and, despite inner VLCKD short-duration feature allowing no sound-enough provisions for long-term outcomes, witnessed in favor of the short-term safety of VLCKD in those patients.Level of evidence Level V: Opinions of authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees.
Collapse
Affiliation(s)
- G Defeudis
- Unit of Endocrinology and Diabetes, Department of Medicine, University Campus Bio-Medico di Roma, Rome, Italy.
| | - M Rossini
- Diet and Diabetes Unit, ASL RM1, Rome, Italy
| | - Y M Khazrai
- Unit of Food Science and Nutrition, Department of Science and Technology for Humans and the Environment, University Campus Bio-Medico di Roma, Rome, Italy
| | - A M V Pipicelli
- UOC di Nefrologia, Dialisi e Trapianto, Dipartimento di Scienze Mediche e Chirurgiche, Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
| | - G Brucoli
- Diet and Diabetes Unit, ASL RM1, Rome, Italy
| | - M Veneziano
- Diet and Diabetes Unit, ASL RM1, Rome, Italy
| | - F Strollo
- Endocrinology and Diabetes Unit, IRCCS San Raffaele Pisana, Rome, Italy
| | | | | | | | | | | | | |
Collapse
|
7
|
Koerich ACC, Borszcz FK, Thives Mello A, de Lucas RD, Hansen F. Effects of the ketogenic diet on performance and body composition in athletes and trained adults: a systematic review and Bayesian multivariate multilevel meta-analysis and meta-regression. Crit Rev Food Sci Nutr 2022; 63:11399-11424. [PMID: 35757868 DOI: 10.1080/10408398.2022.2090894] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
This systematic review with meta-analysis aimed to determine the effects of the ketogenic diet (KD) against carbohydrate (CHO)-rich diets on physical performance and body composition in trained individuals. The MEDLINE, EMBASE, CINAHL, SPORTDiscus, and The Cochrane Library were searched. Randomized and non-randomized controlled trials in athletes/trained adults were included. Meta-analytic models were carried out using Bayesian multilevel models. Eighteen studies were included providing estimates on cyclic exercise modes and strength one-maximum repetition (1-RM) performances and for total, fat, and free-fat masses. There were more favorable effects for CHO-rich than KD on time-trial performance (mode [95% credible interval]; -3.3% [-8.5%, 1.7%]), 1-RM (-5.7% [-14.9%, 2.6%]), and free-fat mass (-0.8 [-3.4, 1.9] kg); effects were more favorable to KD on total (-2.4 [-6.2, 1.8] kg) and fat mass losses (-2.4 [-5.4, 0.2] kg). Likely modifying effects on cyclic performance were the subject's sex and VO2max, intervention and performance durations, and mode of exercise. The intervention duration and subjects' sex were likely to modify effects on total body mass. KD can be a useful strategy for total and fat body losses, but a small negative effect on free-fat mass was observed. KD was not suitable for enhancing strength 1-RM or high-intensity cyclic performances.
Collapse
Affiliation(s)
- Ana Clara C Koerich
- Department of Nutrition, Health Sciences Center, Federal University of Santa Catarina, University Campus, Trindade, Florianópolis, Santa Catarina, Brazil
| | - Fernando Klitzke Borszcz
- Physical Effort Laboratory, Sports Center, Federal University of Santa Catarina, University Campus, Pantanal, Florianópolis, Santa Catarina, Brazil
| | - Arthur Thives Mello
- Department of Nutrition, Health Sciences Center, Federal University of Santa Catarina, University Campus, Trindade, Florianópolis, Santa Catarina, Brazil
| | - Ricardo Dantas de Lucas
- Physical Effort Laboratory, Sports Center, Federal University of Santa Catarina, University Campus, Pantanal, Florianópolis, Santa Catarina, Brazil
| | - Fernanda Hansen
- Department of Nutrition, Health Sciences Center, Federal University of Santa Catarina, University Campus, Trindade, Florianópolis, Santa Catarina, Brazil
| |
Collapse
|
8
|
The Combinatory Effect of Spirulina Supplementation and Resistance Exercise on Plasma Contents of Adipolin, Apelin, Ghrelin, and Glucose in Overweight and Obese Men. Mediators Inflamm 2022; 2022:9539286. [PMID: 35733519 PMCID: PMC9208992 DOI: 10.1155/2022/9539286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 02/16/2022] [Accepted: 03/26/2022] [Indexed: 11/18/2022] Open
Abstract
Methods The current investigation was conducted in a single-blind and quasiexperimental fashion. Sixty overweight and obese men (BMI > 25) ranging in age from 30 to 55 years were purposefully selected and randomly assigned to one of four groups: training plus spirulina (T+S), training plus placebo (T+P), spirulina (S), or placebo (P). For eight weeks, the (S) and (P) groups consumed two 500 mg spirulina and placebo capsules daily, respectively. Resistance training was performed three sessions a week over eight weeks, consisting of 12 movements with 1-, 2-, 3-, and 4-minute rest intervals and 40-90 percent maximal repetition. Adipolin, apelin, and ghrelin indices were measured before and after exercise using special kits. Results All variables changed significantly between groups except for apelin. Within-group comparisons revealed a substantial increase in adipolin levels in the (T+S) and (T+P) groups (P < 0.05). Apelin levels were decreased in the (T+S) and (T+P) groups. Additionally, FBS levels reduced significantly in (T+S) (P = 0.01). Conclusion It seems that eight weeks of circuit resistance training and spirulina supplementation can lead to reduced weight and apelin and FBS levels as well as increased concentrations of adipolin and ghrelin contents in overweight and obese men.
Collapse
|
9
|
Antonio Paoli A, Mancin L, Caprio M, Monti E, Narici MV, Cenci L, Piccini F, Pincella M, Grigoletto D, Marcolin G. Effects of 30 days of ketogenic diet on body composition, muscle strength, muscle area, metabolism, and performance in semi-professional soccer players. J Int Soc Sports Nutr 2021; 18:62. [PMID: 34530857 PMCID: PMC8447662 DOI: 10.1186/s12970-021-00459-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/25/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND A ketogenic diet (KD) is a nutritional approach, usually adopted for weight loss, that restricts daily carbohydrates under 30 g/day. KD showed contradictory results on sport performance, whilst no data are available on team sports. We sought to investigate the influence of a KD on different parameters in semi-professional soccer players. METHODS Subjects were randomly assigned to a iso-protein (1.8 g/Kg body weight/day) ketogenic diet (KD) or western diet (WD) for 30 days. Body weight and body composition, resting energy expenditure (REE), respiratory exchange ratio (RER), cross sectional area (CSA) and isometric muscle strength of quadriceps, counter movement jump (CMJ) and yoyo intermittent recovery test time were measured. RESULTS There was a significantly higher decrease of body fat (p = 0.0359), visceral adipose tissue (VAT) (p = 0.0018), waist circumference (p = 0.0185) and extra-cellular water (p = 0.0060) in KD compared to WD group. Lean soft tissue, quadriceps muscle area, maximal strength and REE showed no changes in both groups. RER decreased significantly in KD (p = 0.0008). Yo-yo intermittent test improved significantly (p < 0.0001) in both groups without significant differences between groups. CMJ significantly improved (p = 0.0021) only in KD. CONCLUSIONS This is the first study investigating the effects of a KD on semi-professional soccer players. In our study KD athletes lost fat mass without any detrimental effects on strength, power and muscle mass. When the goal is a rapid weight reduction in such athletes, the use of a KD should be taken into account. TRIAL REGISTRATION registered retrospectively on Clinical Trial registration number NCT04078971 .
Collapse
Affiliation(s)
- A Antonio Paoli
- Department of Biomedical Sciences, University of Padua, Via Marzolo, 3, 35131, Padua, Italy. .,Research Center for High Performance Sport, UCAM, Catholic University of Murcia, 30107, Murcia, Spain. .,Human Inspired Technology Research Center, University of Padua, Padua, Italy.
| | - Laura Mancin
- Department of Biomedical Sciences, University of Padua, Via Marzolo, 3, 35131, Padua, Italy.,Human Inspired Technology Research Center, University of Padua, Padua, Italy
| | - Massimiliano Caprio
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, Rome, Italy
| | - Elena Monti
- Department of Biomedical Sciences, University of Padua, Via Marzolo, 3, 35131, Padua, Italy
| | - Marco V Narici
- Department of Biomedical Sciences, University of Padua, Via Marzolo, 3, 35131, Padua, Italy
| | - Lorenzo Cenci
- Human Inspired Technology Research Center, University of Padua, Padua, Italy
| | | | - Matteo Pincella
- Inter FC., Milan, Italy.,FIGC Federazione Italiana Giuoco Calcio (Italian Football Federation), Rome, Italy
| | - Davide Grigoletto
- Department of Biomedical Sciences, University of Padua, Via Marzolo, 3, 35131, Padua, Italy
| | - Giuseppe Marcolin
- Department of Biomedical Sciences, University of Padua, Via Marzolo, 3, 35131, Padua, Italy
| |
Collapse
|
10
|
Ketogenic Diet, Physical Activity, and Hypertension-A Narrative Review. Nutrients 2021; 13:nu13082567. [PMID: 34444726 PMCID: PMC8398985 DOI: 10.3390/nu13082567] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/12/2022] Open
Abstract
Several studies link cardiovascular diseases (CVD) with unhealthy lifestyles (unhealthy dietary habits, alcohol consumption, smoking, and low levels of physical activity). Therefore, the strong need for CVD prevention may be pursued through an improved control of CVD risk factors (impaired lipid and glycemic profiles, high blood pressure, and obesity), which is achievable through an overall intervention aimed to favor a healthy lifestyle. Focusing on diet, different recommendations emphasize the need to increase or avoid consumption of entire classes of food, with only partly known and only partly foreseeable consequences on the overall level of health. In recent years, the ketogenic diet (KD) has been proposed to be an effective lifestyle intervention for metabolic syndrome, and although the beneficial effects on weight loss and glucose metabolism seems to be well established, the effects of a prolonged KD on the ability to perform different types of exercise and the influence of KD on blood pressure (BP) levels, both in normotensives and in hypertensives, are not so well understood. The objective of this review is to analyze, on the basis of current evidence, the relationship between KD, regular physical activity, and BP.
Collapse
|
11
|
Effects of a low-carbohydrate ketogenic diet on health parameters in resistance-trained women. Eur J Appl Physiol 2021; 121:2349-2359. [PMID: 34003364 DOI: 10.1007/s00421-021-04707-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 04/29/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE The aim of this study was to evaluate the effect of a ketogenic diet on blood pressure, visceral adipose tissue (VAT), bone mineral content (BMC), and bone mineral density (BMD) in trained women. METHODS Twenty-one resistance-trained women performed an 8-week resistance training program after a 3-week familiarization phase. Participants were randomly assigned to a non-ketogenic diet (n = 11, NKD) or ketogenic diet (n = 10, KD) group. Health parameters were measured before and after the nutritional intervention. Blood pressure was measured using a digital automatic monitor, while VAT, BMC, and BMD changes were measured by dual-energy X-ray absorptiometry. RESULTS There was a significant reduction in systolic blood pressure in KD (mean ± SD [IC 95%], P value, Hedges' g; - 6.3 ± 6.0 [- 10.5, - 2.0] mmHg, P = 0.009, g = - 0.81) but not in NKD (- 0.4 ± 8.9 [- 6.8, 6.0] mmHg, P = 0.890, g = - 0.04). The results on VAT showed no changes in both groups. The KD showed a small favorable effect on BMD (0.02 ± 0.02 [0.01, 0.03] g·cm-2, P = 0.014, g = 0.19) while NKD did not show significant changes (0.00 ± 0.02 [- 0.02, 0.02] g·cm-2, P = 0.886, g = 0.01). No differences in group or in the time × group interaction were found in any of the variables. CONCLUSIONS Consuming a low-carbohydrate high-fat KD in conjunction with a resistance training program might help to promote the improvement of health-related markers in resistance-trained women. Long-term studies are required to evaluate the superiority of a KD in comparison to a traditional diet.
Collapse
|
12
|
Locatelli CAA, Mulvihill EE. Islet Health, Hormone Secretion, and Insulin Responsivity with Low-Carbohydrate Feeding in Diabetes. Metabolites 2020; 10:E455. [PMID: 33187118 PMCID: PMC7697690 DOI: 10.3390/metabo10110455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/05/2020] [Accepted: 11/07/2020] [Indexed: 12/25/2022] Open
Abstract
Exploring new avenues to control daily fluctuations in glycemia has been a central theme for diabetes research since the Diabetes Control and Complications Trial (DCCT). Carbohydrate restriction has re-emerged as a means to control type 2 diabetes mellitus (T2DM), becoming increasingly popular and supported by national diabetes associations in Canada, Australia, the USA, and Europe. This approval comes from many positive outcomes on HbA1c in human studies; yet mechanisms underlying their success have not been fully elucidated. In this review, we discuss the preclinical and clinical studies investigating the role of carbohydrate restriction and physiological elevations in ketone bodies directly on pancreatic islet health, islet hormone secretion, and insulin sensitivity. Included studies have clearly outlined diet compositions, including a diet with 30% or less of calories from carbohydrates.
Collapse
Affiliation(s)
- Cassandra A. A. Locatelli
- Energy Substrate Laboratory, The University of Ottawa Heart Institute, 40 Ruskin Street, H-3229A, Ottawa, ON KIY 4W7, Canada;
- Department of Biochemistry, Microbiology and Immunology, The University of Ottawa, Faculty of Medicine, 451 Smyth Rd, Ottawa, ON K1H 8L1, Canada
| | - Erin E. Mulvihill
- Energy Substrate Laboratory, The University of Ottawa Heart Institute, 40 Ruskin Street, H-3229A, Ottawa, ON KIY 4W7, Canada;
- Department of Biochemistry, Microbiology and Immunology, The University of Ottawa, Faculty of Medicine, 451 Smyth Rd, Ottawa, ON K1H 8L1, Canada
- Montreal Diabetes Research Centre CRCHUM-Pavillion R, 900 Saint-Denis-Room R08.414, Montreal, QC H2X 0A9, Canada
- Centre for Infection, Immunity and Inflammation, The University of Ottawa, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| |
Collapse
|
13
|
Jo E, Silva Ms SC, Auslander PhD AT, Arreglado Ms JP, Elam PhD ML, Osmond Ms AD, Steinberg Ms R, Wong Ms MWH. The Effects of 10-Day Exogenous Ketone Consumption on Repeated Time Trial Running Performances: A Randomized-Control Trial. J Diet Suppl 2020; 19:34-48. [PMID: 33111587 DOI: 10.1080/19390211.2020.1838022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION The effects of ketone salt supplementation on repeated short-distance running time trial (TT) performance in well-trained subjects remain unknown. PURPOSE To determine the effects of 10-day exogenous ketone salt supplementation on two consecutive 800 m running TTs in endurance-trained subjects. METHODS Male and female subjects were randomly allocated to one of the following groups: Ketone (KET) (n = 16) or placebo (CON) (n = 16) (8 m, 8f per group). Subjects underwent two consecutive 800 m TTs before and after a 10-day treatment on a self-propelled treadmill. Time-to-completion of the first (TT1) and second (TT2) TT, the average time-to-completion (TTAVG), and blood lactate response during each TT was measured pre-post-treatment. Changes in blood ketone levels in response to a single dosing were measured pre- and post-treatment. Data was analyzed with a mixed factorial ANOVA with significance set to p < 0.05. RESULTS KET demonstrated a faster TTAVG from pre- to post-treatment (-6.1 ± 8.9 s; p = 0.02) while CON showed no change. At pre- and post-treatment, CON showed no acute changes in blood ketones after a single-dosing while KET demonstrated a significant increases (Pretreatment = +0.4 ± 0.3 mmol/L; p < 0.001; Post-Treatment = +0.4 ± 0.4 mmol/L; p < 0.001). These acute single-dosing responses in blood ketone levels for KET did not change between pre- and post-treatment. There were no interactions for blood lactate response to exercise or fatigue index. CONCLUSIONS In trained subjects, 10 days of ketone salt supplementation does not affect performance in an initial bout of short-distance running, such as during TT1. However, ergogenic effects may be observed under fatigue conditions for example during a repeated running bout.
Collapse
Affiliation(s)
- Edward Jo
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| | - Samantha C Silva Ms
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| | - Alexandra T Auslander PhD
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| | - John P Arreglado Ms
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| | - Marcus L Elam PhD
- Department of Human Nutrition and Food Science, California State Polytechnic University Pomona, Pomona, CA, USA
| | - Adam D Osmond Ms
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| | - Ross Steinberg Ms
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| | - Michael W H Wong Ms
- Department of Kinesiology and Health Promotion, Human Performance Research Laboratory, California State Polytechnic University Pomona, Pomona, CA, USA
| |
Collapse
|
14
|
Hottenrott K, Werner T, Hottenrott L, Meyer TP, Vormann J. Exercise Training, Intermittent Fasting and Alkaline Supplementation as an Effective Strategy for Body Weight Loss: A 12-Week Placebo-Controlled Double-Blind Intervention with Overweight Subjects. Life (Basel) 2020; 10:life10050074. [PMID: 32455547 PMCID: PMC7281477 DOI: 10.3390/life10050074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 05/19/2020] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Intermittent fasting (IF) combined with exercise has been suggested to enhance weight loss. However, both procedures might negatively influence acid-base status. The aim of this study was to determine the combined effects of IF, exercise training and alkaline supplementation in overweight subjects on body composition and running performance. METHODS 80 overweight subjects of age 45.5 ± 7.8 years were assigned to IF or non-intermittent fasting (nIF). Furthermore, subjects were randomly assigned to take either an alkaline supplement (IF-v, nIF-v) or a placebo (IF-p, nIF-p) twice a day. All subjects performed a personalized endurance exercise program (3-4 times/week for 12 weeks). Body weight, body composition, running performance and acid-base parameters were determined before (pre) and after the 12-week program (post). RESULTS 68 participants completed the study. There was a significant effect on body weight loss, body fat loss, visceral fat loss and running performance enhancement in all groups (p < 0.01) for pre and post measurements. Body weight decreased in all groups (IF-p: -5.80 ± 0.77 kg and nIF-p: -3.40 ± 0.58 kg; IF-v: -8.28 ± 0.75 kg and nIF-v: -5.59 ± 0.87 kg). In both dietary strategies, weight loss was significantly further enhanced by alkaline supplementation. The increase in running velocity was significantly higher in IF combined with alkaline supplementation (IF-v 1.73 ± 0.23 km/h and IF-p 0.97 ± 0.20 km/h). In addition, alkaline supplementation increased plasma HCO3- concentration and urinary pH. CONCLUSION Exercise training in combination with IF and alkaline supplementation is an effective strategy to reduce body weight and improve running performance in a 12-week intervention.
Collapse
Affiliation(s)
- Kuno Hottenrott
- Institute for Performance Diagnostics and Health Promotion, Martin-Luther-University of Halle-Wittenberg, 06108 Halle, Germany
| | - Tanja Werner
- NuOmix Research k.s. Applied Nutriomic Research, Martin, 81106 Bratislava, Slovaki
| | - Laura Hottenrott
- Faculty of Sport Science, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Till P Meyer
- Institute of Sport Science, Martin-Luther-University of Halle-Wittenberg, 06108 Halle, Germany
| | - Jürgen Vormann
- Institute for Prevention and Nutrition, 85737 Ismaning, Germany
| |
Collapse
|
15
|
Abstract
The purpose of the present review is to describe how human physiology at very low carbohydrate intakes relates to the criteria for nutritional essentiality. Although we did not limit ourselves to one particular type or function of carbohydrates, we did primarily focus on glucose utilisation as that function was used to determine the recommended daily allowance. In the general population, the human body is able to endogenously synthesise carbohydrates, and does not show signs of deficiency in the absence of dietary carbohydrates. However, in certain genetic defects, such as glycogen storage disease type I, absence of dietary carbohydrates causes abnormalities that are resolved with dietary supplementation of carbohydrates. Therefore, dietary carbohydrates may be defined as conditionally essential nutrients because they are nutrients that are not required in the diet for the general population but are required for specific subpopulations. Ketosis may be considered a physiological normal state due to its occurrence in infants in addition to at very low carbohydrate intakes. Although sources of dietary carbohydrates can provide beneficial micronutrients, no signs of micronutrient deficiencies have been reported in clinical trials of low-carbohydrate ketogenic diets. Nonetheless, more research is needed on how micronutrient requirements can change depending on the dietary and metabolic context. More research is also needed on the role of dietary fibre during a low-carbohydrate ketogenic diet as the beneficial effects of dietary fibre were determined on a standard diet and several studies have shown beneficial effects of decreasing non-digestible carbohydrates.
Collapse
|
16
|
Sherrier M, Li H. The impact of keto-adaptation on exercise performance and the role of metabolic-regulating cytokines. Am J Clin Nutr 2019; 110:562-573. [PMID: 31347659 DOI: 10.1093/ajcn/nqz145] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 06/19/2019] [Indexed: 12/20/2022] Open
Abstract
The ketogenic diet (KD) is a normocaloric diet composed of high-fat, low-carbohydrate, and adequate protein that induces fasting-like effects and results in the production of ketone bodies. Initially used widely for children with refractory epilepsy, the KD gained popularity due to its beneficial effects on weight loss, diabetes, and cancer. In recent years, there has been a resurgence in interest surrounding the KD and exercise performance. This review provides new insights into the adaptation period necessary for enhancement in skeletal muscle fat and ketone oxidation after sustained nutritional ketosis. In addition, this review highlights metabolically active growth factors and cytokines, which may function as important regulators of keto-adaptation in the setting of exercise and the KD.
Collapse
Affiliation(s)
- Matthew Sherrier
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Hongshuai Li
- Musculoskeletal Growth and Regeneration Laboratory, Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| |
Collapse
|
17
|
Murphy EA, Jenkins TJ. A ketogenic diet for reducing obesity and maintaining capacity for physical activity: hype or hope? Curr Opin Clin Nutr Metab Care 2019; 22:314-319. [PMID: 31166223 DOI: 10.1097/mco.0000000000000572] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW This review will evaluate the recent scientific literature on the efficacy of the ketogenic diet for enhancing weight loss and maintaining capacity for physical activity. RECENT FINDINGS With the increasing obesity epidemic, the 21st century has witnessed the emergence of various diet programs aimed at promoting weight loss and enhancing physical performance. The ketogenic diet, a diet high in fat and low in carbohydrates, has been at the forefront. Recent literature has documented significant weight-loss following ketogenic diet interventions. This has been associated with a decrease in systemic inflammation, reduced insulin resistance, and improved lipid profile. Given the importance of physical activity to sustaining a healthy weight, the impact of a ketogenic diet on physical performance has been investigated. The majority of the current literature supports a positive influence of the ketogenic diet on physical activity owing to its ability to maintain performance of both endurance and resistance activities. We highlight the most important recent advances that have been made on the ketogenic diet in relation to obesity and capacity for physical activity. SUMMARY The ketogenic diet is a potentially promising diet for reducing obesity while maintaining capacity for physical activity. However, questions surrounding the sustainability of this diet for the long-term remain.
Collapse
Affiliation(s)
- E Angela Murphy
- Department of Pathology, Microbiology, and Immunology, School of Medicine, University of South Carolina, Columbia
- OptHealth LLC, South Carolina, USA
| | | |
Collapse
|
18
|
Durkalec-Michalski K, Nowaczyk PM, Siedzik K. Effect of a four-week ketogenic diet on exercise metabolism in CrossFit-trained athletes. J Int Soc Sports Nutr 2019; 16:16. [PMID: 30953522 PMCID: PMC6451242 DOI: 10.1186/s12970-019-0284-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 03/26/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The ketogenic diet is becoming a popular nutritional model among athletes. However, the relationship between its use and metabolism during exercise seems to have not been fully investigated. METHODS The aim of the study was to assess the effects of a four-week ketogenic diet (KD) on fat and carbohydrate (CHO) utilization during an incremental cycling test (ICT) in CrossFit-trained female (n = 11) and male (n = 11) athletes. During the ICT (while consuming the customary diet and after the KD), oxygen uptake and carbon dioxide exhalation were registered, and CHO and fat utilization as well as energy expenditure were calculated. RESULTS In males, the KD led to an increase in fat utilization (g·min- 1·kgFFM- 1 and % oxidation). It was particularly noticeable at exercise intensities up to 80% of VO2max. An increase in the area under the curve (AUC) was seen in males but not in females at up to ≤65% VO2max of fat utilization. CONCLUSIONS Male CrossFit-trained athletes seem to be more prone to shifts in macronutrient utilization (in favor of fat utilization) during submaximal intensity exercise under a ketogenic diet than are female athletes. TRIAL REGISTRATION Clinical Trials Gov, NCT03665948 . Registered 11 September 2018 (retrospectively registered).
Collapse
Affiliation(s)
- Krzysztof Durkalec-Michalski
- Institute of Human Nutrition and Dietetics, Poznan University of Life Sciences, Wojska Polskiego 31, 60-624 Poznań, Poland
- Department of Food and Nutrition, Poznan University of Physical Education, 61-871 Poznań, Poland
| | - Paulina M. Nowaczyk
- Institute of Human Nutrition and Dietetics, Poznan University of Life Sciences, Wojska Polskiego 31, 60-624 Poznań, Poland
| | - Katarzyna Siedzik
- Institute of Human Nutrition and Dietetics, Poznan University of Life Sciences, Wojska Polskiego 31, 60-624 Poznań, Poland
| |
Collapse
|
19
|
Anaerobic Performance after a Low-Carbohydrate Diet (LCD) Followed by 7 Days of Carbohydrate Loading in Male Basketball Players. Nutrients 2019; 11:nu11040778. [PMID: 30987297 PMCID: PMC6520927 DOI: 10.3390/nu11040778] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/28/2019] [Accepted: 04/01/2019] [Indexed: 12/22/2022] Open
Abstract
Despite increasing interest among athletes and scientists on the influence of different dietary interventions on sport performance, the association between a low-carbohydrate, high-fat diet and anaerobic capacity has not been studied extensively. The aim of this study was to evaluate the effects of a low-carbohydrate diet (LCD) followed by seven days of carbohydrate loading (Carbo-L) on anaerobic performance in male basketball players. Fifteen competitive basketball players took part in the experiment. They performed the Wingate test on three occasions: after the conventional diet (CD), following 4 weeks of the LCD, and after the weekly Carbo-L, to evaluate changes in peak power (PP), total work (TW), time to peak power (TTP), blood lactate concentration (LA), blood pH, and bicarbonate (HCO3−). Additionally, the concentrations of testosterone, growth hormone, cortisol, and insulin were measured after each dietary intervention. The low-carbohydrate diet procedure significantly decreased total work, resting values of pH, and blood lactate concentration. After the low-carbohydrate diet, testosterone and growth hormone concentrations increased, while the level of insulin decreased. After the Carbo-L, total work, resting values of pH, bicarbonate, and lactate increased significantly compared with the results obtained after the low-carbohydrate diet. Significant differences after the low-carbohydrate diet and Carbo-L procedures, in values of blood lactate concentration, pH, and bicarbonate, between baseline and post exercise values were also observed. Four weeks of the low-carbohydrate diet decreased total work capacity, which returned to baseline values after the carbohydrate loading procedure. Moreover, neither the low-carbohydrate feeding nor carbohydrate loading affected peak power.
Collapse
|
20
|
SPRINTING. . . Dietary Approaches to Optimize Training Adaptation and Performance. Int J Sport Nutr Exerc Metab 2019; 29:85-94. [PMID: 30943814 DOI: 10.1123/ijsnem.2018-0273] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Although sprint athletes are assumed to primarily be interested in promoting muscle hypertrophy, it is the ability to generate explosive muscle power, optimization of power-to-weight ratio, and enhancement of anaerobic energy generation that are key outcomes of sprint training. This reflects the physique of track sprinters, being characterized as ecto-mesomorphs. Although there is little contemporary data on sprinters dietary habits, given their moderate energy requirements relative to body mass, a carbohydrate intake within the range of 3-6 g·kg-1·day-1 appears reasonable, while ensuring carbohydrate availability is optimized around training. Similarly, although protein needs may be twice general population recommendations, sprint athletes should consume meals containing ∼0.4 g/kg high biological value protein (i.e., easily digested, rich in essential amino acids) every 3-5 hr. Despite the short duration of competitions and relative long-recovery periods between races, nutrition still plays an important role in sprint performance. As energy expenditure moderates during competition, so too should intake of energy and macronutrients to prevent unwanted weight gain. Further adjustments in macronutrient intake may be warranted among athletes contemplating optimization of power-to-weight ratio through reductions in body fat prior to the competitive season. Other novel acute methods of weight loss have also been proposed to enhance power-to-weight ratio, but their implementation should only be considered under professional guidance. Given the metabolic demands of sprinting, a few supplements may be of benefit to athletes in training and/or competition. Their use in competition should be preceded with trialing in training to confirm tolerance and perceived ergogenic potential.
Collapse
|
21
|
Wiecek M, Szymura J, Maciejczyk M, Kantorowicz M, Szygula Z. Acute Anaerobic Exercise Affects the Secretion of Asprosin, Irisin, and Other Cytokines - A Comparison Between Sexes. Front Physiol 2018; 9:1782. [PMID: 30618797 PMCID: PMC6295572 DOI: 10.3389/fphys.2018.01782] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/26/2018] [Indexed: 12/26/2022] Open
Abstract
Objective: The new adipokine, which is asprosin, affects glucose release from the liver to the blood, and thus, influences exercise metabolism. This is the first study assessing whether single anaerobic exercise affects asprosin secretion in women and men. Methods: 10 men and 10 women (aged 21.64 ± 1.22 and 22.64 ± 1.49, respectively) performed a single 20-s bicycle sprint. Blood samples were collected before exercise and in the 3′, 15′, 30′, and 60′ of recovery, and 24 h after competition. Results: Only in women did asprosin (P = 0.001) (15′, 30′, 60′, and 24 h after exercise) and irisin (P < 0.001) (15′, 30′, and 60′) concentrations increase. Leptin, however, decreased (P = 0.001) at 3′, 15′, and 30′ in women. There was an increase in interleukin-6 (P < 0.001) at 3′, 15′, 30′, and 60′ of recovery in men, at 15′, 30′, 60′, and 24 h of recovery in women, along with a simultaneous decrease in interleukin-1β (P < 0.001) at 15′, 30′, and 60′ of recovery in men, and at 15′ and 30′ of recovery in women (r = -0.35, P < 0.001). There was a positive correlation between asprosin and adiponectin and a negative one between asprosin and leptin. The increase in irisin concentration at 30′ of recovery was positively correlated with the increase in asprosin concentration and percentage fat content, while being negatively correlated with total and lean body mass (LBM). Conclusion: The single anaerobic effort induced an increase in asprosin and irisin secretion while reducing leptin secretion in women. Adipocytokine concentration changes are inter-related. Regardless of sex, anaerobic efforts induce anti-inflammatory effects.
Collapse
Affiliation(s)
- Magdalena Wiecek
- Department of Physiology and Biochemistry, Faculty of Physical Education and Sport, University of Physical Education in Krakow, Kraków, Poland
| | - Jadwiga Szymura
- Department of Clinical Rehabilitation, Faculty of Motor Rehabilitation, University of Physical Education in Krakow, Kraków, Poland
| | - Marcin Maciejczyk
- Department of Physiology and Biochemistry, Faculty of Physical Education and Sport, University of Physical Education in Krakow, Kraków, Poland
| | - Malgorzata Kantorowicz
- Faculty of Physical Education and Sport, University of Physical Education in Krakow, Kraków, Poland
| | - Zbigniew Szygula
- Department of Physiotherapy, State University of Applied Sciences in Nowy Sacz, Nowy Sącz, Poland
| |
Collapse
|
22
|
Rothschild J, Earnest CP. Dietary Manipulations Concurrent to Endurance Training. J Funct Morphol Kinesiol 2018; 3:jfmk3030041. [PMID: 33466970 PMCID: PMC7739303 DOI: 10.3390/jfmk3030041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 07/11/2018] [Accepted: 07/23/2018] [Indexed: 12/20/2022] Open
Abstract
The role of an athlete's dietary intake (both timing and food type) goes beyond simply providing fuel to support the body's vital processes. Nutritional choices also have an impact on the metabolic adaptations to training. Over the past 20 years, research has suggested that strategically reducing carbohydrate (CHO) availability during an athlete's training can modify the metabolic responses in lieu of simply maintaining a high CHO diet. Several methods have been explored to manipulate CHO availability and include: Low-carb, high-fat (LCHF) diets, performing two-a-day training without glycogen restoration between sessions, and a "sleep-low" approach entailing a glycogen-depleting session in the evening without consuming CHO until after a morning training session performed in an overnight fasted state. Each of these methods can confer beneficial metabolic adaptations for the endurance athlete including increases in mitochondrial enzyme activity, mitochondrial content, and rates of fat oxidation, yet data showing a direct performance benefit is still unclear.
Collapse
Affiliation(s)
| | - Conrad P. Earnest
- Exercise and Sport Nutrition Laboratory, Texas A&M University, College Station, TX 77843, USA
| |
Collapse
|