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Moitzi AM, Krššák M, Klepochova R, Triska C, Csapo R, König D. Effects of a 10-Week Exercise and Nutritional Intervention with Variable Dietary Carbohydrates and Glycaemic Indices on Substrate Metabolism, Glycogen Storage, and Endurance Performance in Men: A Randomized Controlled Trial. SPORTS MEDICINE - OPEN 2024; 10:36. [PMID: 38600291 PMCID: PMC11006643 DOI: 10.1186/s40798-024-00705-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 03/24/2024] [Indexed: 04/12/2024]
Abstract
BACKGROUND Daily nutrition plays an important role in supporting training adaptions and endurance performance. The objective of this 10-week study was to investigate the consequences of varying carbohydrate consumption and the glycaemic index (GI) together with an endurance training regimen on substrate oxidation, muscle energy storage and endurance performance under free-living conditions. Sixty-five moderately trained healthy men (29 ± 4 years; VO2 peak 55 ± 8 mL min-1 kg-1) were randomized to one of three different nutritional regimes (LOW-GI: 50-60% CHO with ≥ 65% of these CHO with GI < 50 per day, n = 24; HIGH-GI: 50-60% CHO with ≥ 65% CHO with GI > 70 per day, n = 20; LCHF: ≤ 50 g CHO daily, n = 21). Metabolic alterations and performance were assessed at baseline (T0) and after 10 weeks (T10) during a graded exercise treadmill test. Additionally, a 5 km time trial on a 400-m outdoor track was performed and muscle glycogen was measured by magnet resonance spectroscopy. RESULTS Total fat oxidation expressed as area under the curve (AUC) during the graded exercise test increased in LCHF (1.3 ± 2.4 g min-1 × km h-1, p < 0.001), remained unchanged in LOW-GI (p > 0.05) and decreased in HIGH-GI (- 1.7 ± 1.5 g min-1 × km h-1, p < 0.001). After the intervention, LOW-GI (- 0.4 ± 0.5 mmol L-1 × km h-1, p < 0.001) and LCHF (- 0.8 ± 0.7 mmol L-1 × km h-1, p < 0.001) showed significantly lower AUC of blood lactate concentrations. Peak running speed increased in LOW-GI (T0: 4.3 ± 0.4 vs. T10: 4.5 ± 0.3 m s-1, p < 0.001) and HIGH-GI (T0: 4.4 ± 0.5 vs. T10: 4.6 ± 0.4 m s-1), while no improvement was observed in LCHF. Yet, time trial performance improved significantly in all groups. Muscle glycogen content increased for participants in HIGH-GI (T0: 97.3 ± 18.5 vs. T10: 144.5 ± 39.8 mmol L wet-tissue-1, p = 0.027) and remained unchanged in the LOW-GI and the LCHF group. At the last examination, muscle glycogen concentration was significantly higher in LOW-GI compared to LCHF (p = 0.014). CONCLUSION Changes in fat oxidation were only present in LCHF, however, lower lactate concentrations in LOW-GI resulted in changes indicating an improved substrate metabolism. Compared to a LCHF diet, changes in peak running speed, and muscle glycogen stores were superior in LOW- and HIGH-GI diets. The low GI diet seems to have an influence on substrate metabolism without compromising performance at higher intensities, suggesting that a high-carbohydrate diet with a low GI is a viable alternative to a LCHF or a high GI diet. TRIAL REGISTRATION Clinical Trials, NCT05241730. https://clinicaltrials.gov/study/NCT05241730 . Registered 25 January 2021.
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Affiliation(s)
- Anna Maria Moitzi
- Division of Nutrition, Exercise and Health, Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria.
- Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria.
- Division of Nurtition, Exercise and Health, Department of Sport and Human Movement Science, University of Vienna, Vienna, Austria.
| | - Martin Krššák
- Department of Biomedical Imaging and Image Guided Therapy, High Field MR Centre of Excellence, Medical University of Vienna, Vienna, Austria
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Radka Klepochova
- Department of Biomedical Imaging and Image Guided Therapy, High Field MR Centre of Excellence, Medical University of Vienna, Vienna, Austria
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Christoph Triska
- Leistungssport Austria, High Performance Centre, Brunn am Gebirge, Lower Austria, Austria
- Division of Training Science, Department of Sport and Human Movement Science, University of Vienna, Vienna, Austria
| | - Robert Csapo
- Division of Training Science, Department of Sport and Human Movement Science, University of Vienna, Vienna, Austria
| | - Daniel König
- Division of Nutrition, Exercise and Health, Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria
- Division of Nurtition, Exercise and Health, Department of Sport and Human Movement Science, University of Vienna, Vienna, Austria
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Xia Q, Lan J, Pan Y, Wang Y, Song T, Yang Y, Tian X, Chen L, Gu Z, Ding YY. Effects of Dityrosine on Lactic Acid Metabolism in Mice Gastrocnemius Muscle During Endurance Exercise via the Oxidative Stress-Induced Mitochondria Damage. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:5269-5282. [PMID: 38439706 DOI: 10.1021/acs.jafc.3c09649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
Dityrosine (Dityr) has been detected in commercial food as a product of protein oxidation and has been shown to pose a threat to human health. This study aims to investigate whether Dityr causes a decrease in lactic acid metabolism in the gastrocnemius muscle during endurance exercise. C57BL/6 mice were administered Dityr or saline by gavage for 13 weeks and underwent an endurance exercise test on a treadmill. Dityr caused a severe reduction in motion displacement and endurance time, along with a significant increase in lactic acid accumulation in the blood and gastrocnemius muscle in mice after exercise. Dityr induced significant mitochondrial defects in the gastrocnemius muscle of mice. Additionally, Dityr induced serious oxidative stress in the gastrocnemius muscle, accompanied by inflammation, which might be one of the causes of mitochondrial dysfunction. Moreover, significant apoptosis in the gastrocnemius muscle increased after exposure to Dityr. This study confirmed that Dityr induced oxidative stress in the gastrocnemius muscle, which further caused significant mitochondrial damage in the gastrocnemius muscle cell, resulting in decreased capacity of lactic acid metabolism and finally affected performance in endurance exercise. This may be one of the possible mechanisms by which highly oxidized foods cause a decreased muscle energy metabolism.
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Affiliation(s)
- Qiudong Xia
- Department of Physical Education, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Jinchi Lan
- Food Safety Key Laboratory of Zhejiang Province, National Experimental Teaching Demonstration Center for Food Engineering and Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Yuxiang Pan
- Food Safety Key Laboratory of Zhejiang Province, National Experimental Teaching Demonstration Center for Food Engineering and Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Yuxin Wang
- Food Safety Key Laboratory of Zhejiang Province, National Experimental Teaching Demonstration Center for Food Engineering and Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Tianyuan Song
- Food Safety Key Laboratory of Zhejiang Province, National Experimental Teaching Demonstration Center for Food Engineering and Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Ying Yang
- Institute of Food Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xu Tian
- Beijing Competitor Sports Nutrition Research Institute, Beijing 100027, China
| | - Longjun Chen
- Huzhou Shengtao Biotechnology LLC, Huzhou 313000, China
| | - Zhenyu Gu
- Food Safety Key Laboratory of Zhejiang Province, National Experimental Teaching Demonstration Center for Food Engineering and Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Yin-Yi Ding
- Food Safety Key Laboratory of Zhejiang Province, National Experimental Teaching Demonstration Center for Food Engineering and Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
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Wang Y, Dong Y, Zhang Y, Yan J, Ren C, Ma H, Cui Z. An 8-week ketogenic diet improves exercise endurance and liver antioxidant capacity after weight loss in obese mice. Front Nutr 2023; 10:1322936. [PMID: 38223504 PMCID: PMC10785402 DOI: 10.3389/fnut.2023.1322936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/30/2023] [Indexed: 01/16/2024] Open
Abstract
Evolving evidence supports the role of the ketogenic diet (KD) in weight loss. However, no coherent conclusions are drawn on its impact on the effect of KD on exercise and antioxidant capacity after weight loss in obese individuals. We evaluated the exercise performance, energy metabolism and antioxidant capacity of mice after weight loss using high-fat diet-induced obese mice, and used KD and normal diet (ND) intervention, respectively, to provide a theoretical basis for further study of the health effects of KD. Our results showed that the 8-week KD significantly reduced the body weight of obese mice and improved the performance of treadmill exercise, but had no significant effect on grip strength. Serum biochemical results suggest that KD has the risk of elevating blood lipid. In liver tissue, KD significantly reduced the level of oxidative stress and increased the antioxidant capacity of the liver. Our findings suggest that the intervention with KD led to weight loss, modulate energy metabolism and improve aerobic exercise endurance in obese mice. Despite its antioxidant potential in the liver, the utilization of KD still requires caution. This study underscores the need for further investigation into the health impacts of KD, especially in regard to its potential risks.
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Affiliation(s)
- Ying Wang
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China
| | - Yunlong Dong
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China
| | - Ying Zhang
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China
| | - Jiabao Yan
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China
| | - Cuiru Ren
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China
| | - Hong Ma
- Sports Department, Xi’an International Studies University, Xi’an, China
| | - Zhenwei Cui
- Centre for Sport Nutrition and Health, Centre for Nutritional Ecology, School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China
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Kaufman M, Nguyen C, Shetty M, Oppezzo M, Barrack M, Fredericson M. Popular Dietary Trends' Impact on Athletic Performance: A Critical Analysis Review. Nutrients 2023; 15:3511. [PMID: 37630702 PMCID: PMC10460072 DOI: 10.3390/nu15163511] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND Nutrition fuels optimal performance for athletes. With increased research developments, numerous diets available, and publicity from professional athletes, a review of dietary patterns impact on athletic performance is warranted. RESULTS The Mediterranean diet is a low inflammatory diet linked to improved power and muscle endurance and body composition. Ketogenic diets are restrictive of carbohydrates and proteins. Though both show no decrements in weight loss, ketogenic diets, which is a more restrictive form of low-carbohydrate diets, can be more difficult to follow. High-protein and protein-paced versions of low-carbohydrate diets have also shown to benefit athletic performance. Plant-based diets have many variations. Vegans are at risk of micronutrient deficiencies and decreased leucine content, and therefore, decreased muscle protein synthesis. However, the literature has not shown decreases in performance compared to omnivores. Intermittent fasting has many different versions, which may not suit those with comorbidities or specific needs as well as lead to decreases in sprint speed and worsening time to exhaustion. CONCLUSIONS This paper critically evaluates the research on diets in relation to athletic performance and details some of the potential risks that should be monitored. No one diet is universally recommend for athletes; however, this article provides the information for athletes to analyze, in conjunction with medical professional counsel, their own diet and consider sustainable changes that can help achieve performance and body habitus goals.
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Affiliation(s)
- Matthew Kaufman
- Department of Orthopaedic Surgery, Stanford University, Redwood City, CA 94063, USA
| | - Chantal Nguyen
- Department of Orthopaedic Surgery, Stanford University, Redwood City, CA 94063, USA
| | - Maya Shetty
- Department of Orthopaedic Surgery, Stanford University, Redwood City, CA 94063, USA
| | - Marily Oppezzo
- Prevention Research Center, Stanford University, Redwood City, CA 94063, USA
| | - Michelle Barrack
- Department of Family and Consumer Sciences, California State University, Long Beach, CA 90840, USA
| | - Michael Fredericson
- Department of Orthopaedic Surgery, Stanford University, Redwood City, CA 94063, USA
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McKay AKA, Ross MLR, Tee N, Sharma AP, Leckey JJ, Burke LM. Adherence to a Ketogenic Low-Carbohydrate, High-Fat Diet Is Associated With Diminished Training Quality in Elite Racewalkers. Int J Sports Physiol Perform 2023:1-9. [PMID: 37263595 DOI: 10.1123/ijspp.2022-0351] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 01/10/2023] [Accepted: 02/10/2023] [Indexed: 06/03/2023]
Abstract
PURPOSE To examine the effects of a high-carbohydrate diet (HCHO), periodized-carbohydrate (CHO) diet (PCHO), and ketogenic low-CHO high-fat diet (LCHF) on training capacity. METHODS Elite male racewalkers completed 3 weeks of periodic training while adhering to their dietary intervention. Twenty-nine data sets were collected from 21 athletes. Each week, 6 mandatory training sessions were completed, with additional sessions performed at the athlete's discretion. Mandatory sessions included an interval session (10 × 1-km efforts on a 6-min cycle), tempo session (14 km with a 450-m elevation gain), 2 long walks (25-40 km), and 2 easy walks (8-12 km) where "sleep-low" and "train-low" dietary strategies were employed for PCHO. Racewalking speed, heart rate, rating of perceived exhaustion, and blood metabolites were collected around key sessions. RESULTS LCHF covered less total distance than HCHO and PCHO (P < .001); however, no differences in training load between groups were evident (P = .285). During the interval sessions, walking speed was slower in LCHF (P = .001), equating to a 2.8% and 5.6% faster speed in HCHO and PCHO, respectively. LCHF was also 3.2% slower in completing the tempo session than HCHO and PCHO (P = .001). Heart rate was higher (P = .002) and lactate concentrations were lower (P < .001) in LCHF compared to other groups, despite slower walking speeds during the interval session. No between-groups differences in rating of perceived exhaustion were evident (P = .077). CONCLUSION Athletes adhering to an LCHF diet showed impaired training capacity relative to their high-CHO-supported counterparts, completing lower training volumes at slower speeds, with higher heart rates.
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Affiliation(s)
- Alannah K A McKay
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC,Australia
| | - Megan L R Ross
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC,Australia
| | - Nicolin Tee
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC,Australia
| | | | | | - Louise M Burke
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC,Australia
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Perez-Montilla JJ, Cuevas-Cervera M, Gonzalez-Muñoz A, Garcia-Rios MC, Navarro-Ledesma S. Efficacy of Nutritional Strategies on the Improvement of the Performance and Health of the Athlete: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19074240. [PMID: 35409921 PMCID: PMC8998415 DOI: 10.3390/ijerph19074240] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/28/2022] [Accepted: 03/31/2022] [Indexed: 02/04/2023]
Abstract
Evidence shows that the use of food strategies can impact health, but a clear consensus about how the effects of different food strategies impact improvement in the athlete’s performance and health remain unclear. This study evaluated how food strategies, specifically intermittent fasting and a ketogenic diet affect health and performance in healthy athletes. Study selection for this review was based on clinical trial studies analyzing changes in performance and health in athletes. The Pubmed, Web of Science, PEDro, Dialnet, Scopus, CINAHL, ProQuest, Medline and Cochrane databases were searched. The Physiotherapy Evidence Database (PEDro) scale, PEDro Internal Validity Scale (IVS) and Standard Quality Assessment Criteria for Evaluating Primary Research Papers from a variety of fields (QUALSYT) checklists were used to evaluate the risk of bias of the included studies. Articles were selected based on criteria concerning the effectiveness of nutritional strategies on athletes’ performance; articles should be randomized clinical trials (RCTs) or uncontrolled clinical trials; they should be human studies and they should have been published less than 7 years ago. A total of 15 articles were evaluated, 8 randomised clinical trials and 7 non-randomized clinical studies, with 411 participants who satisfied our inclusion criteria and were included in this review. The results of the study showed intermittent fasting and time-restricted feeding as strategies that produce health benefits. On the other hand, the ketogenic diet did not reach an appropriate consensus. The articles presented a medium level of methodological quality in the PEDro scale, low quality in IVS scale and high quality in QUALSYT scale. Despite the lack of studies analyzing changes in the performance and health of athletes after the use of different nutritional strategies, intermittent fasting and time-restricted feeding should be considered since they seem to be effective, and further studies are necessary.
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Affiliation(s)
- J. Javier Perez-Montilla
- Department of Physiotherapy, Faculty of Health Sciences, Campus of Melilla, University of Granada, Querol Street, 5, 52004 Melilla, Spain; (J.J.P.-M.); (M.C.-C.)
| | - Maria Cuevas-Cervera
- Department of Physiotherapy, Faculty of Health Sciences, Campus of Melilla, University of Granada, Querol Street, 5, 52004 Melilla, Spain; (J.J.P.-M.); (M.C.-C.)
| | - Ana Gonzalez-Muñoz
- Clínica Ana González, Avenida Hernan Nuñez de Toledo 6, 29018 Malaga, Spain
- Correspondence: (A.G.-M.); (S.N.-L.)
| | - Maria Carmen Garcia-Rios
- Department of Physiotherapy, Faculty of Health Sciences, University of Granada, 18071 Granada, Spain;
| | - Santiago Navarro-Ledesma
- Department of Physiotherapy, Faculty of Health Sciences, Campus of Melilla, University of Granada, Querol Street, 5, 52004 Melilla, Spain; (J.J.P.-M.); (M.C.-C.)
- Correspondence: (A.G.-M.); (S.N.-L.)
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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.
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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:
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Paoli A, Cenci L, Pompei P, Sahin N, Bianco A, Neri M, Caprio M, Moro T. Effects of Two Months of Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, and Blood Parameters in Competitive Natural Body Builders. Nutrients 2021; 13:nu13020374. [PMID: 33530512 PMCID: PMC7911670 DOI: 10.3390/nu13020374] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 12/19/2022] Open
Abstract
Background: Ketogenic diet (KD) is a nutritional approach that restricts daily carbohydrates, replacing most of the reduced energy with fat, while maintaining an adequate quantity of protein. Despite the widespread use of KD in weight loss in athletes, there are still many concerns about its use in sports requiring muscle mass accrual. Thus, the present study sought to investigate the influence of a KD in competitive natural body builders. Methods: Nineteen volunteers (27.4 ± 10.5 years) were randomly assigned to ketogenic diet (KD) or to a western diet (WD). Body composition, muscle strength and basal metabolic rate were measured before and after two months of intervention. Standard blood biochemistry, testosterone, IGF-1, brain-derived neurotrophic factor (BDNF) and inflammatory cytokines (IL6, IL1β, TNFα) were also measured. Results: Body fat significantly decreased in KD (p = 0.030); whilst lean mass increased significantly only in WD (p < 0.001). Maximal strength increased similarly in both groups. KD showed a significant decrease of blood triglycerides (p < 0.001), glucose (p = 0.001), insulin (p < 0.001) and inflammatory cytokines compared to WD whilst BDNF increased in both groups with significant greater changes in KD (p < 0.001). Conclusions: KD may be used during body building preparation for health and leaning purposes but with the caution that hypertrophic muscle response could be blunted.
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Affiliation(s)
- Antonio Paoli
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy;
- Research Center for High Performance Sport, UCAM, Catholic University of Murcia, 30107 Murcia, Spain
| | - Lorenzo Cenci
- Brain, Mind and Computer Science Doctoral Program, University of Padua, 35131 Padua, Italy;
| | - PierLuigi Pompei
- Unit of Pharmacology, School of Pharmacy, University of Camerino, 62032 Camerino, Italy;
| | - Nese Sahin
- Faculty of Sport Science, Ankara University, 06830 Ankara, Turkey;
| | - Antonino Bianco
- Department of Psychology, Educational Science and Human Movement, Sport and Exercise Sciences Research Unit, University of Palermo, 90128 Palermo, Italy;
| | - Marco Neri
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, 00166 Rome, Italy; (M.N.); (M.C.)
| | - Massimiliano Caprio
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, 00166 Rome, Italy; (M.N.); (M.C.)
- Laboratory of Cardiovascular Endocrinology, IRCCS San Raffaele Pisana, 00163 Rome, Italy
| | - Tatiana Moro
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy;
- Correspondence: ; Tel.: +39-049-827-5306
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