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 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
|
Corona G, Rastrelli G, Sparano C, Vignozzi L, Sforza A, Maggi M. Advances in the treatment of functional male hypogonadism. Expert Rev Endocrinol Metab 2024; 19:163-177. [PMID: 38117229 DOI: 10.1080/17446651.2023.2296022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 12/13/2023] [Indexed: 12/21/2023]
Abstract
INTRODUCTION Functional hypogonadism is frequently found in obese men, particularly those with metabolic complications. Several possible therapeutic approaches could be considered. AREAS COVERED An extensive search on Medline, Embase, and Cochrane databases was performed to retrieve the available studies assessing the change of testosterone (T) and sexual function upon dieting or physical activity programs, as well as glucagon-like peptide 1 analogues. The role of lifestyle interventions associated with T replacement therapy (TRT) was also evaluated. The expert opinion provided here has been corroborated by meta-analyzing the results of the retrieved studies. EXPERT OPINION Current evidence supports the beneficial role of lifestyle modifications in increasing T and improving sexual function as a function of weight loss. While dieting programs are associated with greater effects in younger populations, physical exercise has major effects in older ones. Among the dieting programs, a very low-calorie ketogenic diet shows the best results; aerobic or endurance physical exercise perform similarly. The advantages of functional hypogonadism in lifestyle modifications are empowered by the association with TRT. Therefore, TRT may be a valuable complementary strategy to increase muscle mass and facilitate physical exercise while improving sexual symptoms, thus favoring the motivation and compliance for lifestyle interventions.
Collapse
Affiliation(s)
- Giovanni Corona
- Endocrinology Unit, Azienda Usl, Maggiore-Bellaria Hospital, Bologna, Italy
| | - Giulia Rastrelli
- Andrology, Women's Endocrinology and Gender Incongruence Unit, Florence, Italy
| | - Clotilde Sparano
- Mario Serio" Department of Experimental and Clinical Biomedical Sciences, University of Florence, Endocrinology Unit, Florence, Italy
| | - Linda Vignozzi
- Andrology, Women's Endocrinology and Gender Incongruence Unit, Florence, Italy
| | - Alessandra Sforza
- Endocrinology Unit, Azienda Usl, Maggiore-Bellaria Hospital, Bologna, Italy
| | - Mario Maggi
- Mario Serio" Department of Experimental and Clinical Biomedical Sciences, University of Florence, Endocrinology Unit, Florence, Italy
| |
Collapse
|
3
|
Durkalec-Michalski K, Kamińska J, Saunders B, Pokrywka A, Łoniewski I, Steffl M, Podgórski T. Does sodium bicarbonate based extra-cellular buffering support reduce high intensity exercise-induced fatigue and enhance short-term recovery assessed by selected blood biochemical indices? Biol Sport 2024; 41:17-27. [PMID: 38188117 PMCID: PMC10765444 DOI: 10.5114/biolsport.2024.125591] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 02/06/2023] [Accepted: 02/12/2023] [Indexed: 01/09/2024] Open
Abstract
Exercise-induced metabolic processes induce muscle acidification which contributes to a reduction in the ability to perform repeated efforts. Alkalizing agents such as sodium bicarbonate (NaHCO3) prevent large blood pH changes, however, there is no evidence on whether regulation of acid-base balance may also support whole body homeostasis monitored through heamatological and biochemical blood markers in a dose-dependent manner. Thirty Cross-Fit-trained participants were studied in a randomized, multi cross-over, placebo (PLA)-controlled double-blind manner in which they performed a control session (CTRL, without supplementation), three NaHCO3 visits (three different doses) and PLA (sodium chloride in an equimolar amount of sodium as NaHCO3). Each visit consisted of two 30-s Wingate tests separated by CrossFit-specific benchmarks (Wall Balls and Burpees - both performed for 3 min). Blood samples were collected at rest, immediately post-exercise and after 45 min recovery. Significant differences between visits appeared for blood pH, percentage of lymphocytes and granulocytes, red blood cells count and haemoglobin concentration at post-exercise and 45-min recovery, and for white blood cells count, percentage of monocytes, concentration of magnesium and creatinine at 45-min recovery. Most of the observed differences for heamatological and biochemical markers were significant compared to CTRL, but not different after PLA. NaHCO3 supplementation compared to PLA did not significantly affect exercise or recovery shifts in studied blood indicators. However, the changes in these markers after NaHCO3 and PLA in relation to CTRL indicate a possible role of sodium.
Collapse
Affiliation(s)
- Krzysztof Durkalec-Michalski
- Department of Sports Dietetics, Poznan University of Physical Education, 61-871 Poznan, Poland
- Sport Sciences–Biomedical Department, Faculty of Physical Education and Sport, Charles University, 162 52 Prague, Czech Republic
| | - Joanna Kamińska
- Department of Physiology and Biochemistry, Poznan University of Physical Education, 61-871 Poznan, Poland
| | - Bryan Saunders
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, Rheumatology Division, Faculdade de Medicina FMUSP, University of São Paulo, São Paulo, Brazil
- Institute of Orthopedics and Traumatology, Faculty of Medicine FMUSP, University of São Paulo, Brazil
| | - Andrzej Pokrywka
- Department of Biochemistry and Pharmacogenomics, Medical University of Warsaw, 02-097 Warsaw, Poland
| | - Igor Łoniewski
- Department of Biochemical Sciences, Pomeranian Medical University in Szczecin, 71-460 Szczecin, Poland
| | - Michal Steffl
- Sport Sciences–Biomedical Department, Faculty of Physical Education and Sport, Charles University, 162 52 Prague, Czech Republic
| | - Tomasz Podgórski
- Department of Physiology and Biochemistry, Poznan University of Physical Education, 61-871 Poznan, Poland
| |
Collapse
|
4
|
Webb KL, Gorman EK, Morkeberg OH, Klassen SA, Regimbal RJ, Wiggins CC, Joyner MJ, Hammer SM, Senefeld JW. The relationship between hemoglobin and [Formula: see text]: A systematic review and meta-analysis. PLoS One 2023; 18:e0292835. [PMID: 37824583 PMCID: PMC10569622 DOI: 10.1371/journal.pone.0292835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 09/29/2023] [Indexed: 10/14/2023] Open
Abstract
OBJECTIVE There is widespread agreement about the key role of hemoglobin for oxygen transport. Both observational and interventional studies have examined the relationship between hemoglobin levels and maximal oxygen uptake ([Formula: see text]) in humans. However, there exists considerable variability in the scientific literature regarding the potential relationship between hemoglobin and [Formula: see text]. Thus, we aimed to provide a comprehensive analysis of the diverse literature and examine the relationship between hemoglobin levels (hemoglobin concentration and mass) and [Formula: see text] (absolute and relative [Formula: see text]) among both observational and interventional studies. METHODS A systematic search was performed on December 6th, 2021. The study procedures and reporting of findings followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Article selection and data abstraction were performed in duplicate by two independent reviewers. Primary outcomes were hemoglobin levels and [Formula: see text] values (absolute and relative). For observational studies, meta-regression models were performed to examine the relationship between hemoglobin levels and [Formula: see text] values. For interventional studies, meta-analysis models were performed to determine the change in [Formula: see text] values (standard paired difference) associated with interventions designed to modify hemoglobin levels or [Formula: see text]. Meta-regression models were then performed to determine the relationship between a change in hemoglobin levels and the change in [Formula: see text] values. RESULTS Data from 384 studies (226 observational studies and 158 interventional studies) were examined. For observational data, there was a positive association between absolute [Formula: see text] and hemoglobin levels (hemoglobin concentration, hemoglobin mass, and hematocrit (P<0.001 for all)). Prespecified subgroup analyses demonstrated no apparent sex-related differences among these relationships. For interventional data, there was a positive association between the change of absolute [Formula: see text] (standard paired difference) and the change in hemoglobin levels (hemoglobin concentration (P<0.0001) and hemoglobin mass (P = 0.006)). CONCLUSION These findings suggest that [Formula: see text] values are closely associated with hemoglobin levels among both observational and interventional studies. Although our findings suggest a lack of sex differences in these relationships, there were limited studies incorporating females or stratifying results by biological sex.
Collapse
Affiliation(s)
- Kevin L. Webb
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ellen K. Gorman
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Olaf H. Morkeberg
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Stephen A. Klassen
- Department of Kinesiology, Brock University, St. Catharines, Ontario, Canada
| | - Riley J. Regimbal
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Chad C. Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Michael J. Joyner
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Shane M. Hammer
- Department of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Jonathon W. Senefeld
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois
| |
Collapse
|
5
|
Cignarelli A, Santi D, Genchi VA, Conte E, Giordano F, Di Leo S, Natalicchio A, Laviola L, Giorgino F, Perrini S. Very low-calorie ketogenic diet rapidly augments testosterone levels in non-diabetic obese subjects. Andrology 2023; 11:234-244. [PMID: 36459060 DOI: 10.1111/andr.13357] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/21/2022] [Accepted: 11/29/2022] [Indexed: 12/04/2022]
Abstract
BACKGROUND The very low-calorie ketogenic diet (VLCKD) represents an opportunity to attain clinically relevant weight loss in obese patients. Functional hypogonadism represents a frequent hormonal disorder associated with obesity and visceral fat accumulation characterised by low testosterone levels and subnormal luteinising hormone (LH) levels. AIM To evaluate the early effects of VLCKD on serum total testosterone (TT) levels in non-diabetic obese patients. METHODS Twenty-two obese male patients (mean age 39.3 ± 11.7 years, mean body mass index (BMI) 38.2 ± 6.4 kg/m2 ) were enrolled and treated for 28 days with VLCKD. Anthropometric and hormonal variables were assessed before, during and after diet intervention. RESULTS After 7 and 28 days on a VLCKD, a significant and persistent reduction in body weight, BMI, fat mass, blood glucose, insulin and homeostasis model assessment index was observed compared with baseline. TT significantly increased after 7 days (+35 ± 64 ng/dl) and 28 days (+74 ± 97 ng/dl) on a VLCKD. In addition to TT, a significant increase in serum sex hormone-binding globulin levels was observed after 7 (+2.1 ± 4.1) and 28 days (+7.7 ± 10.0). However, both calculated free testosterone and LH did not change after 7 or 28 days of VLCKD. Following cessation of VLCKD, hypogonadal subjects achieved a higher percentage of total weight loss (8.5% ± 1.5%), a greater reduction in weight (-9.94 ± 1.66 kg), fat mass (-7 ± 2.1 kg) and waist circumference (-6.31 ± 2.65 cm) and a greater improvement in glycaemia (-8.75 ± 10.92 mg/dl) as compared with eugonadal subjects. Furthermore, hypogonadal subjects exhibited a trend of higher TT increase (+98.12 ± 71.51 ng/dl) as compared with eugonadal subjects. CONCLUSIONS VLCKD results in rapid improvements in TT levels associated with weight loss in male obese non-diabetic subjects, particularly in the presence of obesity-related hypogonadism.
Collapse
Affiliation(s)
- Angelo Cignarelli
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Daniele Santi
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Valentina Annamaria Genchi
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Eleonora Conte
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Fiorella Giordano
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Simona Di Leo
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Annalisa Natalicchio
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Luigi Laviola
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Giorgino
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Sebastio Perrini
- Department of Precision and Regenerative Medicine and Ionian Area, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| |
Collapse
|
6
|
Furini C, Spaggiari G, Simoni M, Greco C, Santi D. Ketogenic state improves testosterone serum levels-results from a systematic review and meta-analysis. Endocrine 2023; 79:273-282. [PMID: 36149528 DOI: 10.1007/s12020-022-03195-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/04/2022] [Indexed: 02/04/2023]
Abstract
BACKGROUND It is widely demonstrated that obesity and hypogonadism are bi-directionally correlated, since the hypogonadism prevalence is higher in obese population, while weight loss increases testosterone serum levels. Several approaches are available to contrast weight excess, from simple dietary regimens to more complex surgical procedures. Ketogenic diets (KD) fit in this context and their application is growing year after year, aiming to improve the metabolic and weight patterns in obese patients. However, KD influence on testosterone levels is still poorly investigated. OBJECTIVES To systematically evaluate the potential effect of KD on testosterone levels. METHODS A systematic literature search was performed until April 2022 including studies investigating testosterone levels before and after KD. Secondary endpoints were body weight, estradiol and sex-hormone binding globulin serum levels. Any kind of KD was considered eligible, and no specific criteria for study populations were provided. RESULTS Seven studies (including eight trials) were included in the analysis for a total of 230 patients, five using normocaloric KD and three very low calories KD (VLCKD). Only three studies enrolled overweight/obese men. A significant total testosterone increase was recorded after any kind of KD considering 111 patients (2.86 [0.95, 4.77], p = 0.003). This increase was more evident considering VLCKD compared to normocaloric KD (6.75 [3.31, 10.20], p < 0.001, versus 0.98 [0.08, 1.88], p = 0.030). Meta-regression analyses highlighted significant correlations between the post-KD testosterone raise with patients' age (R-squared 36.4, p < 0.001) and weight loss (R-squared 73.6, p < 0.001). CONCLUSIONS Comprehensively, KD improved testosterone levels depending on both patients' age and KD-induced weight loss. However, the lack of information in included studies on hormones of the hypothalamic-pituitary-gonadal axis prevents an exhaustive comprehension about mechanisms connecting ketosis and testosterone homeostasis.
Collapse
Affiliation(s)
- Chiara Furini
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, Modena, Italy
| | - Giorgia Spaggiari
- Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, Modena, Italy
| | - Manuela Simoni
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, Modena, Italy
| | - Carla Greco
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy.
- Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, Modena, Italy.
| | - Daniele Santi
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Ospedale Civile di Baggiovara, Modena, Italy
| |
Collapse
|
7
|
Komka Z, Szilágyi B, Molnár D, Sipos B, Tóth M, Sonkodi B, Ács P, Elek J, Szász M. Exercise-related hemoconcentration and hemodilution in hydrated and dehydrated athletes: An observational study of the Hungarian canoeists. PLoS One 2022; 17:e0277978. [PMID: 36584041 PMCID: PMC9803156 DOI: 10.1371/journal.pone.0277978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 11/08/2022] [Indexed: 12/31/2022] Open
Abstract
Hemoconcentration during exercise is a well-known phenomenon, however, the extent to which dehydration is involved is unclear. In our study, the effect of dehydration on exercise-induced hemoconcentration was examined in 12 elite Hungarian kayak-canoe athletes. The changes of blood markers were examined during acute maximal workload in hydrated and dehydrated states. Dehydration was achieved by exercise, during a 120-minute extensive-aerobic preload. Our research is one of the first studies in which the changes in blood components were examined with a higher time resolution and a wider range of the measured parameters. Hydration status had no effect on the dynamics of hemoconcentration during both the hydrated (HS) and dehydrated (DHS) load, although lower maximal power output were measured after the 120-minute preload [HS Hemoglobin(Hgb)Max median 17.4 (q1 17.03; q3 17.9) g/dl vs. DHS HgbMax median 16.9 (q1 16.43; q3 17.6) g/dl (n.s); HS Hematocrit(Hct)Max 53.50 (q1 52.28; q3 54.8) % vs. DHS HctMax 51.90 (q1 50.35; q3 53.93) % (n.s)]. Thirty minutes after the maximal loading, complete hemodilution was confirmed in both exercises. Dehydration had no effect on hemoconcentration or hemodilution in the recovery period [HS HgbR30' 15.7 (q1 15.15; q3 16.05) g/dl (n.s.) vs. DHS HgbR30' 15.75 (q1 15.48; q3 16.13) g/dl (n.s.), HS HctR30' 48.15 (q1 46.5; q3 49.2) % vs. DHS HctR30' 48.25 (q1 47.48; q3 49.45) % (n.s.)], however, plasma osmolality did not follow a corresponding decrease in hemoglobin and hematocrit in the dehydrated group. Based on our data, metabolic products (glucose, lactate, sodium, potassium, chloride, bicarbonate ion, blood urea nitrogen) induced osmolality may not play a major role in the regulation of hemoconcentration and post-exercise hemodilution. From our results, we can conclude that hemoconcentration depends mainly on the intensity of the exercise.
Collapse
Affiliation(s)
- Zsolt Komka
- Department of Health Sciences and Sports Medicine, Hungarian University of Sports Science, Budapest, Hungary
- Heart and Vascular Center, Semmelweis University, Budapest, Hungary
- Hungarian Canoe Federation, Budapest, Hungary
- * E-mail:
| | - Brigitta Szilágyi
- Institute of Mathematics, Budapest University of Technology and Economics, Budapest, Hungary
- Institute of Mathematics and Statistical Modelling, Corvinus University of Budapest, Budapest, Hungary
| | - Dóra Molnár
- Hungarian Canoe Federation, Budapest, Hungary
| | - Bence Sipos
- Faculty of Natural Sciences Department of Geometry, Budapest University of Technology and Economics, Budapest, Hungary
| | - Miklós Tóth
- Department of Health Sciences and Sports Medicine, Hungarian University of Sports Science, Budapest, Hungary
- Faculty of Health Sciences, University of Pécs, Pécs, Hungary
- Department of Laboratory Medicine, Semmelweis University, Budapest, Hungary
- Szentágothai Research Center, Pécs, Hungary
| | - Balázs Sonkodi
- Department of Health Sciences and Sports Medicine, Hungarian University of Sports Science, Budapest, Hungary
| | - Pongrác Ács
- Faculty of Health Sciences, University of Pécs, Pécs, Hungary
- Szentágothai Research Center, Pécs, Hungary
| | - János Elek
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | | |
Collapse
|
8
|
Abstract
A recent meta-analysis found low-carbohydrate, high-protein diets (> 3.4 g/kg of bodyweight/day) (g/kg/day) decreased men's total testosterone (∼5.23 nmol/L) [Whittaker and Harris (2022) Low-carbohydrate diets and men's cortisol and testosterone: systematic review and meta-analysis. Nutrition and Health. DOI: 10.1177/02601060221083079]. This finding has generated substantial discussion, however, it has often lacked clarity and context, with the term 'high-protein' being used unqualified. Firstly, diets < 3.4 g/kg/day are not associated with a consistent decrease in testosterone. Secondly, the average protein intake is ∼1.3 g/kg/day, conventional 'high-protein' diets are ∼1.8-3 g/kg/day and the vast majority of athletes are < 3.4 g/kg/day; meaning very few individuals will ever surpass 3.4 g/kg/day. To avoid such confusion in the future, the following definitions are proposed: very high (> 3.4 g/kg/day), high (1.9-3.4 g/kg/day), moderate (1.25-1.9 g/kg/day) and low (<1.25 g/kg/day). Using these, very high-protein diets (> 3.4 g/kg/day) appear to decrease testosterone, however high- and moderate-protein diets (1.25-3.4 g/kg/day) do not.
Collapse
Affiliation(s)
- Joseph Whittaker
- The School of Allied Health and Community, 8709University of Worcester, UK
| |
Collapse
|
9
|
Ficarra S, Di Raimondo D, Navarra GA, Izadi M, Amato A, Macaluso FP, Proia P, Musiari G, Buscemi C, Barile AM, Randazzo C, Tuttolomondo A, Buscemi S, Bellafiore M. Effects of Mediterranean Diet Combined with CrossFit Training on Trained Adults’ Performance and Body Composition. J Pers Med 2022; 12:jpm12081238. [PMID: 36013187 PMCID: PMC9409826 DOI: 10.3390/jpm12081238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 07/24/2022] [Accepted: 07/25/2022] [Indexed: 11/16/2022] Open
Abstract
CrossFit is a high-intensity training discipline increasingly practiced in recent years. Specific nutritional approaches are usually recommended to maximize performance and improve body composition in high-intensity training regimens; notwithstanding, to date there are no targeted nutritional recommendations for CrossFit athletes. The Mediterranean Diet (MD) is a diet approach with a well-designed proportion of macronutrients, using only available/seasonal food of the Mediterranean area, whose health benefits are well demonstrated. No studies have evaluated this dietary strategy among CrossFit athletes and practitioners; for this reason, we tested the effects of 8 weeks of MD on CrossFit athletes’ performance and body composition. Participants were assigned to two groups: a diet group (DG) in which participants performed CrossFit training plus MD, and a control group (CG) in which participants partook in the CrossFit training, continuing their habitual diet. Participants were tested before and after the 8 weeks of intervention. At the end of the study, no significant difference was noted in participants’ body composition, whereas improvements in anaerobic power, explosive strength of the lower limbs, and CrossFit-specific performance were observed only in the DG. Our results suggest that adopting a MD in CrossFit athletes/practitioners could be a useful strategy to improve specific strength, endurance, and anaerobic capacity while maintaining overall body composition.
Collapse
Affiliation(s)
- Salvatore Ficarra
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| | - Domenico Di Raimondo
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
- Correspondence: ; Tel.: +39-091-6552180
| | - Giovanni Angelo Navarra
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| | - Mohammad Izadi
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| | - Alessandra Amato
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| | - Francesco Paolo Macaluso
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| | - Patrizia Proia
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| | - Gaia Musiari
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
| | - Carola Buscemi
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
| | - Anna Maria Barile
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
| | - Cristiana Randazzo
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
| | - Antonino Tuttolomondo
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
| | - Silvio Buscemi
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) “G. D’Alessandro”, University of Palermo, Piazza delle Cliniche, 90127 Palermo, Italy; (G.M.); (C.B.); (A.M.B.); (C.R.); (A.T.); (S.B.)
| | - Marianna Bellafiore
- Sport and Exercise Sciences Research Unit, Department of Psychology, Educational Science and Human Movement, University of Palermo, Via Giovanni Pascoli 6, 90144 Palermo, Italy; (S.F.); (G.A.N.); (M.I.); (A.A.); (F.P.M.); (P.P.); (M.B.)
| |
Collapse
|
10
|
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
|
11
|
Zdzieblik D, Friesenborg H, Gollhofer A, König D. A high carbohydrate diet with a low glycaemic index improves training effects in male endurance athletes. Int J Food Sci Nutr 2022; 73:965-972. [PMID: 35758204 DOI: 10.1080/09637486.2022.2091525] [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: 10/17/2022]
Abstract
The present study investigated the effect of a 4-week high fat low carbohydrate (HFLC-G) versus high carbohydrate low glycaemic (LGI-G) or high glycaemic (HGI-G) diet on power output at lactate thresholds, peak oxygen uptake and peak performance during an incremental cycle test in 28 male endurance athletes. All participants showed improved levels of power output at the lactate thresholds with a more pronounced effect in the HFLC-G and LGI-G. In the HFLC-G peak performance (-11.6 ± 16.3 W) decreased, while in the LGI-G (9.20 ± 13.8 W) and HGI-G (9.89 ± 12.8 W) peak performance increased (p = 0.009). In summary, the LGI-G showed comparable training adaptations as the HFLC-G at submaximal intensities without limiting the ability to perform at high intensities. Compared to a HFLC and HGI diet, the LGI diet in this study seemed to be advantageous during submaximal and high intensities resulting from an improved metabolic flexibility.
Collapse
Affiliation(s)
- Denise Zdzieblik
- Department for Nutrition, Institute for Sports and Sports Science, University of Freiburg, Freiburg, Germany
| | - Hilke Friesenborg
- Department for Nutrition, Institute for Sports and Sports Science, University of Freiburg, Freiburg, Germany
| | - Albert Gollhofer
- Department for Nutrition, Institute for Sports and Sports Science, University of Freiburg, Freiburg, Germany
| | - Daniel König
- Department for Nutrition, Exercise and Health, Centre for Sports Science and University Sports, University of Vienna, Vienna, Austria.,Department for Nutrition, Exercise and Health, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| |
Collapse
|
12
|
Zdzieblik D, Friesenborg H, Gollhofer A, König D. Effect of a High Fat Diet vs. High Carbohydrate Diets With Different Glycemic Indices on Metabolic Parameters in Male Endurance Athletes: A Pilot Trial. Front Nutr 2022; 9:802374. [PMID: 35479739 PMCID: PMC9037589 DOI: 10.3389/fnut.2022.802374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/04/2022] [Indexed: 12/20/2022] Open
Abstract
Consuming low glycemic carbohydrates leads to an increased muscle fat utilization and preservation of intramuscular glycogen, which is associated with improved flexibility to metabolize either carbohydrates or fats during endurance exercise. The purpose of this trial was to investigate the effect of a 4-week high fat low carbohydrate (HFLC-G: ≥65% high glycemic carbohydrates per day; n = 9) vs. high carbohydrate low glycemic (LGI-G: ≥65% low glycemic carbohydrates daily; n = 10) or high glycemic (HGI-G: ≥65% fat, ≤ 50 g carbohydrates daily; n = 9) diet on fat and carbohydrate metabolism at rest and during exercise in 28 male athletes. Changes in metabolic parameters under resting conditions and during cycle ergometry (submaximal and with incremental workload) from pre- to post-intervention were determined by lactate diagnostics and measurements of the respiratory exchange ratio (RER). Additionally, body composition and perceptual responses to the diets [visual analog scale (VAS)] were measured. A significance level of α = 0.05 was considered. HFLC-G was associated with markedly decreased lactate concentrations during the submaximal (−0.553 ± 0.783 mmol/l, p = 0.067) and incremental cycle test [−5.00 ± 5.71 (mmol/l) × min; p = 0.030] and reduced RER values at rest (−0.058 ± 0.108; p = 0.146) during the submaximal (−0.078 ± 0.046; p = 0.001) and incremental cycle test (−1.64 ± 0.700 RER × minutes; p < 0.001). In the HFLC-G, fat mass (p < 0.001) decreased. In LGI-G lactate, concentrations decreased in the incremental cycle test [−6.56 ± 6.65 (mmol/l) × min; p = 0.012]. In the LGI-G, fat mass (p < 0.01) and VAS values decreased, indicating improved levels of gastrointestinal conditions and perception of effort during training. The main findings in the HGI-G were increased RER (0.047 ± 0.076; p = 0.117) and lactate concentrations (0.170 ± 0.206 mmol/l, p = 0.038) at rest. Although the impact on fat oxidation in the LGI-G was not as pronounced as following the HFLC diet, the adaptations in the LGI-G were consistent with an improved metabolic flexibility and additional benefits regarding exercise performance in male athletes.
Collapse
Affiliation(s)
- Denise Zdzieblik
- Department for Nutrition, Institute for Sports and Sports Science, University of Freiburg, Freiburg, Germany
| | - Hilke Friesenborg
- Department for Nutrition, Institute for Sports and Sports Science, University of Freiburg, Freiburg, Germany
| | - Albert Gollhofer
- Department for Nutrition, Institute for Sports and Sports Science, University of Freiburg, Freiburg, Germany
| | - Daniel König
- Centre for Sports Science and University Sports, Department for Nutrition, Exercise and Health, University of Vienna, Vienna, Austria.,Department for Nutrition, Exercise and Health, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| |
Collapse
|
13
|
Saito H, Wada N, Iida K. Isonitrogenous low-carbohydrate diet elicits specific changes in metabolic gene expression in the skeletal muscle of exercise-trained mice. PLoS One 2022; 17:e0262875. [PMID: 35061842 PMCID: PMC8782354 DOI: 10.1371/journal.pone.0262875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 01/06/2022] [Indexed: 11/28/2022] Open
Abstract
With the renewed interest in low-carbohydrate diets (LCDs) in the sports field, a few animal studies have investigated their potential. However, most rodent studies have used an LCD containing low protein, which does not recapitulate a human LCD, and the muscle-specific adaptation in response to an LCD remains unclear. Therefore, we investigated the effects of two types of LCDs, both containing the same proportion of protein as a regular diet (isonitrogenous LCD; INLCD), on body composition, exercise performance, and metabolic fuel selection at the genetic level in the skeletal muscles of exercise-trained mice. Three groups of mice (n = 8 in each group), one fed a regular AIN-93G diet served as the control, and the others fed either of the two INLCDs containing 20% protein and 10% carbohydrate (INLCD-10%) or 20% protein and 1% carbohydrate (INLCD-1%) had a regular exercise load (5 times/week) for 12 weeks. Body weight and muscle mass did not decrease in either of the INLCD-fed groups, and the muscle glycogen levels and endurance capacity did not differ among the three groups. Only in the mice fed INLCD-1% did the plasma ketone concentration significantly increase, and gene expression related to glucose utilization significantly declined in the muscles. Both INLCD-1% and INLCD-10% consumption increased gene expression related to lipid utilization. These results suggest that, although INLCD treatment did not affect endurance capacity, it helped maintain muscle mass and glycogen content regardless of the glucose intake restrictions in trained mice. Moreover, an INLCD containing a low carbohydrate content might present an advantage by increasing lipid oxidation without ketosis and suppressing muscle glucose utilization.
Collapse
Affiliation(s)
- Hazuki Saito
- Department of Food and Nutrition Science, Graduate School of Humanities and Sciences, Ochanomizu University, Otsuka, Bunkyo, Tokyo, Japan
| | - Naoko Wada
- Department of Food and Nutrition Science, Graduate School of Humanities and Sciences, Ochanomizu University, Otsuka, Bunkyo, Tokyo, Japan
| | - Kaoruko Iida
- Department of Food and Nutrition Science, Graduate School of Humanities and Sciences, Ochanomizu University, Otsuka, Bunkyo, Tokyo, Japan
- The Institute for Human Life Innovation, Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan
- * E-mail:
| |
Collapse
|
14
|
Effect of a Four-Week Vegan Diet on Performance, Training Efficiency and Blood Biochemical Indices in CrossFit-Trained Participants. Nutrients 2022; 14:nu14040894. [PMID: 35215544 PMCID: PMC8878731 DOI: 10.3390/nu14040894] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/10/2022] [Accepted: 02/15/2022] [Indexed: 01/27/2023] Open
Abstract
This interventional study examined the effect of a four-week vegan diet (VegD) during a four-week high-intensity functional training (HIFT) on performance, training results and blood biochemical indices in female (n = 12) and male (n = 8) moderate-trained CrossFit participants. The whole study group performed the maximum number of repetitions with a load of 70% one repetition-maximum (1RM) and a modified Fight Gone Bad (FGBMod) test before and after a dietary intervention (the group was divided to follow a VegD or a traditional mixed diet (MixD)) in a randomised and parallel design. Pre-exercise resting blood samples were also analysed. There was a significant improvement in the number of repetitions performed at a load corresponding to 70% of 1RM in the classic squat in the MixD group (p < 0.001), and in the classic deadlift in the VegD group (p = 0.014). Furthermore, there was a significant improvement in the results of the FGBMod performance test after a MixD. Moreover, an improvement in some exercises in the modified FGBMod test (Wall Ball after the VegD and the MixD, and rowing after the MixD) was also observed. However, differences between the MixD and the VegD groups were not clinically relevant. In conclusion, the short-term study conducted here indicated that a VegD in HIFT training positively affects strength endurance in the classic deadlift but is unlikely to be more beneficial in improving performance than a MixD.
Collapse
|
15
|
Henselmans M, Bjørnsen T, Hedderman R, Vårvik FT. The Effect of Carbohydrate Intake on Strength and Resistance Training Performance: A Systematic Review. Nutrients 2022; 14:nu14040856. [PMID: 35215506 PMCID: PMC8878406 DOI: 10.3390/nu14040856] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 12/04/2022] Open
Abstract
High carbohydrate intakes are commonly recommended for athletes of various sports, including strength trainees, to optimize performance. However, the effect of carbohydrate intake on strength training performance has not been systematically analyzed. A systematic literature search was conducted for trials that manipulated carbohydrate intake, including supplements, and measured strength, resistance training or power either acutely or after a diet and strength training program. Studies were categorized as either (1) acute supplementation, (2) exercise-induced glycogen depletion with subsequent carbohydrate manipulation, (3) short-term (2–7 days) carbohydrate manipulation or (4) changes in performance after longer-term diet manipulation and strength training. Forty-nine studies were included: 19 acute, six glycogen depletion, seven short-term and 17 long-term studies. Participants were strength trainees or athletes (39 studies), recreationally active (six studies) or untrained (four studies). Acutely, higher carbohydrate intake did not improve performance in 13 studies and enhanced performance in six studies, primarily in those with fasted control groups and workouts with over 10 sets per muscle group. One study found that a carbohydrate meal improved performance compared to water but not in comparison to a sensory-matched placebo breakfast. There was no evidence of a dose-response effect. After glycogen depletion, carbohydrate supplementation improved performance in three studies compared to placebo, in particular during bi-daily workouts, but not in research with isocaloric controls. None of the seven short-term studies found beneficial effects of carbohydrate manipulation. Longer-term changes in performance were not influenced by carbohydrate intake in 15 studies; one study favored the higher- and one the lower-carbohydrate condition. Carbohydrate intake per se is unlikely to strength training performance in a fed state in workouts consisting of up to 10 sets per muscle group. Performance during higher volumes may benefit from carbohydrates, but more studies with isocaloric control groups, sensory-matched placebos and locally measured glycogen depletion are needed.
Collapse
Affiliation(s)
- Menno Henselmans
- The International Scientific Research Foundation for Fitness and Nutrition, David Blesstraat 28HS, 1073 LC Amsterdam, The Netherlands; (R.H.); (F.T.V.)
- Correspondence: ; Tel.: +31-61-809-5999
| | - Thomas Bjørnsen
- Department of Sport Science and Physical Education, Faculty of Health and Sport Sciences, University of Agder, 4630 Kristiansand, Norway;
| | - Richie Hedderman
- The International Scientific Research Foundation for Fitness and Nutrition, David Blesstraat 28HS, 1073 LC Amsterdam, The Netherlands; (R.H.); (F.T.V.)
| | - Fredrik Tonstad Vårvik
- The International Scientific Research Foundation for Fitness and Nutrition, David Blesstraat 28HS, 1073 LC Amsterdam, The Netherlands; (R.H.); (F.T.V.)
- Department of Sport Science and Physical Education, Faculty of Health and Sport Sciences, University of Agder, 4630 Kristiansand, Norway;
| |
Collapse
|
16
|
Reactive Oxygen Species (ROS) and Antioxidants as Immunomodulators in Exercise: Implications for Heme Oxygenase and Bilirubin. Antioxidants (Basel) 2022; 11:antiox11020179. [PMID: 35204062 PMCID: PMC8868548 DOI: 10.3390/antiox11020179] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/12/2022] [Accepted: 01/14/2022] [Indexed: 02/07/2023] Open
Abstract
Exercise is commonly prescribed as a lifestyle treatment for chronic metabolic diseases as it functions as an insulin sensitizer, cardio-protectant, and essential lifestyle tool for effective weight maintenance. Exercise boosts the production of reactive oxygen species (ROS) and subsequent transient oxidative damage, which also upregulates counterbalancing endogenous antioxidants to protect from ROS-induced damage and inflammation. Exercise elevates heme oxygenase-1 (HO-1) and biliverdin reductase A (BVRA) expression as built-in protective mechanisms, which produce the most potent antioxidant, bilirubin. Together, these mitigate inflammation and adiposity. Moderately raising plasma bilirubin protects in two ways: (1) via its antioxidant capacity to reduce ROS and inflammation, and (2) its newly defined function as a hormone that activates the nuclear receptor transcription factor PPARα. It is now understood that increasing plasma bilirubin can also drive metabolic adaptions, which improve deleterious outcomes of weight gain and obesity, such as inflammation, type II diabetes, and cardiovascular diseases. The main objective of this review is to describe the function of bilirubin as an antioxidant and metabolic hormone and how the HO-1-BVRA-bilirubin-PPARα axis influences inflammation, metabolic function and interacts with exercise to improve outcomes of weight management.
Collapse
|
17
|
Effects of a Low-Carbohydrate High-Fat Diet Combined with High-Intensity Interval Training on Body Composition and Maximal Oxygen Uptake: A Systematic Review and Meta-Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182010740. [PMID: 34682481 PMCID: PMC8535842 DOI: 10.3390/ijerph182010740] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/04/2021] [Accepted: 10/06/2021] [Indexed: 12/13/2022]
Abstract
The low-carbohydrate high-fat (LCHF) diet has recently been subject to attention on account of its reported influences on body composition and physical performance. However, the combined effect of LCHF with high-intensity interval training (HIIT) is unclear. A systematic review and meta-analysis were conducted to explore the effect of the LCHF diet combined with HIIT on human body composition (i.e., body weight (BM), body mass index (BMI), fat mass (FM), body fat percentage (BFP), fat-free mass (FFM)) and maximal oxygen uptake (VO2max). Online libraries (PubMed, Web of Science, EMBASE, Cochrane Library, EBSCO, CNKI, Wan Fang) were used to search initial studies until July 2021, from which 10 out of 2440 studies were included. WMD served as the effect size with a confidence interval value of 95%. The results of meta-analysis showed a significant reduction in BM (WMD = −5.299; 95% CI: −7.223, −3.376, p = 0.000), BMI (WMD = −1.150; 95% CI: −2.225, −0.075, p = 0.036), BFP (WMD = −2.787; 95% CI: −4.738, −0.835, p = 0.005) and a significant increase in VO2max (WMD = 3.311; 95% CI: 1.705, 4.918, p = 0.000), while FM (WMD = −2.221; 95% CI: −4.582, 0.139, p = 0.065) and FFM (WMD = 0.487; 95% CI: −3.512, 4.469, p = 0.814) remained unchanged. In conclusion, the LCHF diet combined with HIIT can reduce weight and fat effectively. This combination is sufficient to prevent muscle mass loss during LCHF, and further enhance VO2max. Further research might be required to clarify the effect of other types of exercise on body composition and physical performance during LCHF.
Collapse
|
18
|
Valenzuela PL, Castillo-García A, Lucia A, Naclerio F. Effects of Combining a Ketogenic Diet with Resistance Training on Body Composition, Strength, and Mechanical Power in Trained Individuals: A Narrative Review. Nutrients 2021; 13:nu13093083. [PMID: 34578961 PMCID: PMC8469041 DOI: 10.3390/nu13093083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/11/2021] [Accepted: 08/30/2021] [Indexed: 01/20/2023] Open
Abstract
Ketogenic diets (KD) have gained popularity in recent years among strength-trained individuals. The present review summarizes current evidence—with a particular focus on randomized controlled trials—on the effects of KD on body composition and muscle performance (strength and power output) in strength-trained individuals. Although long-term studies (>12 weeks) are lacking, growing evidence supports the effectiveness of an ad libitum and energy-balanced KD for reducing total body and fat mass, at least in the short term. However, no or negligible benefits on body composition have been observed when comparing hypocaloric KD with conventional diets resulting in the same energy deficit. Moreover, some studies suggest that KD might impair resistance training-induced muscle hypertrophy, sometimes with concomitant decrements in muscle performance, at least when expressed in absolute units and not relative to total body mass (e.g., one-repetition maximum). KD might therefore be a beneficial strategy for promoting fat loss, although it might not be a recommendable option to gain muscle mass and strength/power. More research is needed on the adoption of strategies for avoiding the potentially detrimental effect of KD on muscle mass and strength/power (e.g., increasing protein intake, reintroduction of carbohydrates before competition). In summary, evidence is as yet scarce to support a major beneficial effect of KD on body composition or performance in strength-trained individuals. Furthermore, the long-term effectiveness and safety of this type of diet remains to be determined.
Collapse
Affiliation(s)
- Pedro L. Valenzuela
- Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (P.L.V.); (A.L.)
| | | | - Alejandro Lucia
- Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (P.L.V.); (A.L.)
- Physical Activity and Health Research Group (‘PaHerg’), Research Institute of the Hospital 12 de Octubre (‘imas12’), 28041 Madrid, Spain
| | - Fernando Naclerio
- Institute for Lifecourse Development, School of Human Sciences, Centre for Exercise Activity and Rehabilitation, University of Greenwich, London SE10 9LS, UK
- Correspondence: or
| |
Collapse
|
19
|
Cao J, Lei S, Wang X, Cheng S. The Effect of a Ketogenic Low-Carbohydrate, High-Fat Diet on Aerobic Capacity and Exercise Performance in Endurance Athletes: A Systematic Review and Meta-Analysis. Nutrients 2021; 13:nu13082896. [PMID: 34445057 PMCID: PMC8400555 DOI: 10.3390/nu13082896] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/02/2021] [Accepted: 08/19/2021] [Indexed: 12/29/2022] Open
Abstract
A low-carbohydrate, high-fat (LCHF) diet has been proposed to enhance the fat utilization of muscle and the aerobic capacity of endurance athletes, thereby improving their exercise performance. However, it remains uncertain how the macronutrient intake shift from carbohydrate to fat affects endurance exercise training and performance. This study performed a systematic review and meta-analysis to explore the effects of a ketogenic low-carbohydrate, high-fat (K-LCHF) diet on aerobic capacity and exercise performance among endurance athletes. Searches were carried out in five electronic databases, and we followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The search included studies using an LCHF diet as an intervention protocol and compared data on factors such as maximum oxygen uptake (VO2max) and rating of perceived exertion (RPE) from the graded exercise test. In this case, 10 studies met the criteria and were included in the meta-analysis. We did not find a significant effect of K-LCHF diet interventions on VO2max, time to exhaustion, HRmax or RPE. However, a significant overall effect in the substrate oxidation response to respiratory exchange rate was observed. The meta-analysis showed that K-LCHF diets did not affect aerobic capacity and exercise performance. Therefore, high-quality interventions of a K-LCHF diet are needed to illustrate its effect on various endurance training programs.
Collapse
Affiliation(s)
- Jingguo Cao
- Exercise, Health and Technology Centre, Department of Physical Education, Shanghai Jiao Tong University, Shanghai 200240, China; (J.C.); (S.L.); (S.C.)
| | - Siman Lei
- Exercise, Health and Technology Centre, Department of Physical Education, Shanghai Jiao Tong University, Shanghai 200240, China; (J.C.); (S.L.); (S.C.)
- Faculty of Education, University of Macau, Macau SAR, China
| | - Xiuqiang Wang
- Exercise, Health and Technology Centre, Department of Physical Education, Shanghai Jiao Tong University, Shanghai 200240, China; (J.C.); (S.L.); (S.C.)
- Exercise Translational Medicine Centre, Shanghai Centre for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, China
- Correspondence:
| | - Sulin Cheng
- Exercise, Health and Technology Centre, Department of Physical Education, Shanghai Jiao Tong University, Shanghai 200240, China; (J.C.); (S.L.); (S.C.)
- Exercise Translational Medicine Centre, Shanghai Centre for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, China
- Faculty of Sport and Health Science, University of Jyväskylä, 40014 Jyväskylä, Finland
| |
Collapse
|
20
|
The Effects of Fasting or Ketogenic Diet on Endurance Exercise Performance and Metabolism in Female Mice. Metabolites 2021; 11:metabo11060397. [PMID: 34207054 PMCID: PMC8234851 DOI: 10.3390/metabo11060397] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/12/2021] [Accepted: 06/15/2021] [Indexed: 01/13/2023] Open
Abstract
The promotion of ketone body (KB) metabolism via ketosis has been suggested as a strategy to increase exercise performance. However, studies in humans and animals have yielded inconsistent results. The purpose of the current study was to examine the effects of ketosis, achieved via fasting or a short-term ketogenic diet (KD), on endurance exercise performance in female mice. After 8 h of fasting, serum KB significantly increased and serum glucose significantly decreased in fasted compared to fed mice. When subjected to an endurance exercise capacity (EEC) test on a motorized treadmill, both fed and fasted mice showed similar EEC performance. A 5-week KD (90% calories from fat) significantly increased serum KB but did not increase EEC times compared to chow-fed mice. KD mice gained significantly more weight than chow-fed mice and had greater adipose tissue mass. Biochemical tissue analysis showed that KD led to significant increases in triglyceride content in the heart and liver and significant decreases in glycogen content in the muscle and liver. Furthermore, KD downregulated genes involved in glucose and KB oxidation and upregulated genes involved in lipid metabolism in the heart. These findings suggest that a short-term KD is not an effective strategy to enhance exercise performance and may lead to increased adiposity, abnormal endogenous tissue storage, and cardiometabolic remodeling.
Collapse
|
21
|
Durkalec-Michalski K, Zawieja EE, Zawieja BE, Podgórski T. Evaluation of the repeatability and reliability of the cross-training specific Fight Gone Bad workout and its relation to aerobic fitness. Sci Rep 2021; 11:7263. [PMID: 33790372 PMCID: PMC8012697 DOI: 10.1038/s41598-021-86660-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 03/18/2021] [Indexed: 11/09/2022] Open
Abstract
Cross-training is a high-intensity functional training (HIFT) with multiple workout modalities. Despite the increasing number of studies in HIFT, there is still no validated test to measure its specific performance. It would also be advisable to determine whether selected cross-training workouts can implement a stimulus corresponding to maximize aerobic work. For these reasons, the purpose of our study was to evaluate the repeatability and reliability of Fight Gone Bad (FGB) workout and to assess its relationship with aerobic fitness. Twenty-one cross-training participants (9 females) finished the study protocol which included three two-day measurement sessions separated by 10 days. During each session, participants had their body composition measured, and they performed two exercise tests. The first test was an incremental cycling test to measure aerobic fitness, and the second was a cross-training specific FGB workout performed the next day. Reliability and repeatability were calculated from the three measurements. The total FGB Score (FGBTOTAL) showed excellent reliability (ICC 0.9, SEM 6%). Moreover, FGBTOTAL was strongly correlated with aerobic fitness (i.e., time to exhaustion (Texh, R2 = 0.72), maximal workload (Wmax, R2 = 0.69), time to gas exchange threshold (TGET, R2 = 0.68), and peak oxygen uptake (VO2peak, R2 = 0.59). We also found that agreement between standardized FGB and standardized aerobic performance indices such as Texh, VO2peak, Wmax, maximum heart rate, TGET, and workload at gas exchange threshold was high by the Bland-Altman method. In conclusion, FGB is a reliable test that can be used in order to measure changes in cross-training performance caused by an intervention. Moreover, FGB is strongly correlated to aerobic fitness.
Collapse
Affiliation(s)
- Krzysztof Durkalec-Michalski
- Department of Sports Dietetics, Poznan University of Physical Education, 61-871, Poznan, Poland.
- Department of Human Nutrition and Dietetics, Poznan University of Life Sciences, 60-624, Poznan, Poland.
| | - Emilia E Zawieja
- Department of Human Nutrition and Dietetics, Poznan University of Life Sciences, 60-624, Poznan, Poland
| | - Bogna E Zawieja
- Department of Mathematical and Statistical Methods, Poznan University of Life Sciences, 60-637, Poznan, Poland
| | - Tomasz Podgórski
- Department of Physiology and Biochemistry, Poznan University of Physical Education, 61-871, Poznan, Poland
| |
Collapse
|