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Zhang XL, Zhang Q, Zhang X, Gu QW, Pan JJ, Pei YF, Li JF, Jiang F, Diao LJ, Zhou HM, Ding HM, Zhang ZL, Zhou GM, Wang WJ, Li BY. Effect of vitamin D 3 supplementation in winter on physical performance of university students: a one-month randomized controlled trial. J Int Soc Sports Nutr 2023; 20:2258850. [PMID: 37735799 PMCID: PMC10540648 DOI: 10.1080/15502783.2023.2258850] [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: 03/10/2023] [Accepted: 09/07/2023] [Indexed: 09/23/2023] Open
Abstract
BACKGROUND There is epidemiological evidence which suggests an association between 25-hydroxyvitamin D [25(OH)D] levels and bone and muscle function; however, it is unclear whether vitamin D supplementation has an added benefit beyond bone health. Here, we investigated the effects of vitamin D3 supplementation (1 month) on physical performance in Chinese university students in winter. METHODS One hundred and seventeen eligible subjects with 25(OH)D (19.2 ± 7.8 ng/mL) were randomly assigned to either vitamin D3 supplement (N = 56; 1000 IU/day) or the control (N = 61) group for 1 month. Pre- and post-measurements included: 1) serum levels of 25(OH)D; 2) musculoskeletal and pulmonary function [vertical jump height (VJH) and right handgrip strength (RHS), forced vital capacity (FVC), and forced expiratory volume at 1s (FEV1)]; 3) bone turnover markers [parathyroid hormone (PTH), n-terminal osteocalcin (N-MID), and calcium]; 4) hemoglobin-related parameters [hemoglobin (Hb), hematocrit (HCT), red blood cells (RBC), and red cell distribution width (RDW)]; 5) lipid parameters [total triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)]; 6) Fatigue-related indicators [serum creatine kinase (CK), lactate dehydrogenase (LDH), and total testosterone (T)]. In addition, aerobic capacity was assessed by measuring maximal oxygen uptake (VO2max) at baseline. RESULTS During wintertime, supplementation with 1000 IU/d of vitamin D3 significantly increased serum 25(OH)D levels (from 18.85 ± 7.04 to 26.98 ± 5.88 ng/mL, p < 0.05), accompanied by a decrease of PTH (p < 0.05). However, vitamin D3 supplementation did not significantly impact the physical performance, serum lipid parameters, and bone turnover markers of students. Furthermore, 25(OH)D was found to be positively correlated with VJH and negatively correlated with PTH and TC at the beginning and end of the study (p < 0.05). In addition, the multiple linear regression analysis showed that 25(OH)D combined with athletic, gender, height, weight, Hb, and FVC could account for 84.0% of the VO2max value. CONCLUSIONS The study demonstrated that one-month of 1000 IU/d of vitamin D3 supplementation during the winter had beneficial effects on 25(OH)D status and PTH. However, vitamin D3 intervention was not sufficient to improve physical performance. Furthermore, 25(OH)D levels combined with athletic, Hb and FVC could be a predictor of VO2max.
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Affiliation(s)
- Xiao-Li Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Qing Zhang
- School of Physical Education and Sports Science, Soochow University, Suzhou 215021, China
| | - Xu Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Qin-Wen Gu
- School of Physical Education and Sports Science, Soochow University, Suzhou 215021, China
| | - Jin-Jing Pan
- Department of Nutrition and Food Hygiene, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Yu-Fang Pei
- Department of Epidemiology and Biostatistics, School of Public Health, Soochow University, Suzhou, China
| | - Jia-Fu Li
- Department of Occupational and Environmental Health, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Fei Jiang
- Department of Occupational and Environmental Health, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Ling-Jing Diao
- Department of Nutrition and Food Hygiene, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Hui-Ming Zhou
- Department of Nutrition and Food Hygiene, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Hong-Mei Ding
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zeng-Li Zhang
- Department of Occupational and Environmental Health, School of Public Health, Medical College of Soochow University, Suzhou, China
| | - Guang-Ming Zhou
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, China
| | - Wen-Jun Wang
- School of Physical Education and Sports Science, Soochow University, Suzhou 215021, China
| | - Bing-Yan Li
- Department of Nutrition and Food Hygiene, School of Public Health, Medical College of Soochow University, Suzhou, China
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Jiménez-Casquet MJ, Conde-Pipó J, Valenzuela-Barranco I, Rienda-Contreras R, Olea-Serrano F, Bouzas C, Tur JA, Mariscal-Arcas M. Nutrition Status of Female Winter Sports Athletes. Nutrients 2023; 15:4472. [PMID: 37892548 PMCID: PMC10609974 DOI: 10.3390/nu15204472] [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: 09/12/2023] [Revised: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 10/29/2023] Open
Abstract
Eating disorders, especially restrictive eating, are common among female athletes. There are two main types of winter sports: those that are practiced outdoors on snow (-25 to +5 °C and 2500 m), such as alpine skiing and snowboarding, and those that are practiced indoors on ice (5-10 °C at low altitude), such as figure skating and ice hockey. The aim of this research was to identify the nutritional status and potential risk of female athletes practicing winter sports, considering the altitude of training. The sample was composed of 58 women (aged 19.81 years (SD: 12.61)) who were competitors in some winter sports. Anthropometrics and nutritional variables were taken. Statistically significant differences were found between HA and LA groups for all the characteristics except thigh skinfold, and neither group had an energy intake (EI) that matched their total energy expenditure (TEE). Both groups met at least two-thirds of the RDI for all minerals and vitamins except iodine, fluorine, vitamin D, vitamin E, and retinol. This study suggests that female winter sports athletes have insufficient energy, vitamin, and mineral intake, which can be worsened with altitude.
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Affiliation(s)
- María José Jiménez-Casquet
- Health Science and Nutrition Research (HSNR-CTS1118), Department of Nutrition and Food Science, School of Pharmacy, University of Granada, 18071 Granada, Spain; (M.J.J.-C.); (J.C.-P.); (F.O.-S.)
| | - Javier Conde-Pipó
- Health Science and Nutrition Research (HSNR-CTS1118), Department of Nutrition and Food Science, School of Pharmacy, University of Granada, 18071 Granada, Spain; (M.J.J.-C.); (J.C.-P.); (F.O.-S.)
| | | | - Raquel Rienda-Contreras
- Department of Sports and Women, Andalusian Federation of Winter Sports (FADI), 18008 Granada, Spain;
| | - Fátima Olea-Serrano
- Health Science and Nutrition Research (HSNR-CTS1118), Department of Nutrition and Food Science, School of Pharmacy, University of Granada, 18071 Granada, Spain; (M.J.J.-C.); (J.C.-P.); (F.O.-S.)
- Instituto de Investigación Biosanitaria de Granada (ibs.GRANADA), 18012 Granada, Spain
| | - Cristina Bouzas
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands-IUNICS & IDISBA, 07122 Palma de Mallorca, Spain; (C.B.); (J.A.T.)
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Institute of Health Carlos III, 28029 Madrid, Spain
- Health Research Institute of the Balearic Islands, 07120 Palma de Mallorca, Spain
| | - Josep A. Tur
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands-IUNICS & IDISBA, 07122 Palma de Mallorca, Spain; (C.B.); (J.A.T.)
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Institute of Health Carlos III, 28029 Madrid, Spain
- Health Research Institute of the Balearic Islands, 07120 Palma de Mallorca, Spain
| | - Miguel Mariscal-Arcas
- Health Science and Nutrition Research (HSNR-CTS1118), Department of Nutrition and Food Science, School of Pharmacy, University of Granada, 18071 Granada, Spain; (M.J.J.-C.); (J.C.-P.); (F.O.-S.)
- Instituto de Investigación Biosanitaria de Granada (ibs.GRANADA), 18012 Granada, Spain
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Ghazzawi HA, Hussain MA, Raziq KM, Alsendi KK, Alaamer RO, Jaradat M, Alobaidi S, Al Aqili R, Trabelsi K, Jahrami H. Exploring the Relationship between Micronutrients and Athletic Performance: A Comprehensive Scientific Systematic Review of the Literature in Sports Medicine. Sports (Basel) 2023; 11:109. [PMID: 37368559 DOI: 10.3390/sports11060109] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 06/29/2023] Open
Abstract
The aim of this systematic review is twofold: (i) to examine the effects of micronutrient intake on athletic performance and (ii) to determine the specific micronutrients, such as vitamins, minerals, and antioxidants, that offer the most significant enhancements in terms of athletic performance, with the goal of providing guidance to athletes and coaches in optimizing their nutritional strategies. The study conducted a systematic search of electronic databases (i.e., PubMed, Web of Science, Scopus) using keywords pertaining to micronutrients, athletic performance, and exercise. The search involved particular criteria of studies published in English between 1950 and 2023. The findings suggest that vitamins and minerals are crucial for an athlete's health and physical performance, and no single micronutrient is more important than others. Micronutrients are necessary for optimal metabolic body's functions such as energy production, muscle growth, and recovery, which are all important for sport performance. Meeting the daily intake requirement of micronutrients is essential for athletes, and while a balanced diet that includes healthy lean protein sources, whole grains, fruits, and vegetables is generally sufficient, athletes who are unable to meet their micronutrient needs due to malabsorption or specific deficiencies may benefit from taking multivitamin supplements. However, athletes should only take micronutrient supplements with the consultation of a specialized physician or nutritionist and avoid taking them without confirming a deficiency.
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Affiliation(s)
- Hadeel Ali Ghazzawi
- Department Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman 11942, Jordan
| | - Mariam Ali Hussain
- Department of Psychiatry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama 323, Bahrain
| | - Khadija Majdy Raziq
- Department of Psychiatry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama 323, Bahrain
| | - Khawla Khaled Alsendi
- Department of Psychiatry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama 323, Bahrain
| | - Reem Osama Alaamer
- Department of Psychiatry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama 323, Bahrain
| | - Manar Jaradat
- Department Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman 11942, Jordan
| | - Sondos Alobaidi
- Department Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman 11942, Jordan
| | - Raghad Al Aqili
- Department Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman 11942, Jordan
| | - Khaled Trabelsi
- High Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax 3000, Tunisia
- Research Laboratory-Education, Motricity, Sport and Health, University of Sfax, Sfax 3000, Tunisia
| | - Haitham Jahrami
- Department of Psychiatry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama 323, Bahrain
- Government Hospitals, Ministry of Health, Manama 323, Bahrain
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Bârsan M, Chelaru VF, Râjnoveanu AG, Popa ȘL, Socaciu AI, Bădulescu AV. Difference in Levels of Vitamin D between Indoor and Outdoor Athletes: A Systematic Review and Meta-Analysis. Int J Mol Sci 2023; 24:ijms24087584. [PMID: 37108748 PMCID: PMC10147028 DOI: 10.3390/ijms24087584] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 04/11/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Vitamin D, its importance in different processes taking place in the human body, the effects of abnormal levels of this hormone, either too low or too high, and the need for supplementation have been extensively researched thus far. Variances in exposure to sunlight can cause vitamin D levels to fluctuate. Indoor activity can be a factor for these fluctuations and can lead to a decrease in vitamin D levels. We conducted a systematic review and meta-analysis aiming to identify whether indoor compared to outdoor training has a significant influence on vitamin D levels; we also performed subgroup analyses and multivariate meta-regression. The type of training has an impact on vitamin D levels that is influenced by multiple cofounders. In a subgroup analysis not considering cofounders, the mean serum vitamin D was 3.73 ng/mL higher in outdoor athletes, a difference which barely fails to achieve significance (p = 0.052, a total sample size of 5150). The indoor-outdoor difference is only significant (clinically and statistically) when considering studies performed exclusively on Asian athletes (a mean difference of 9.85 ng/mL, p < 0.01, and a total sample size of 303). When performing the analyses within each season, no significant differences are observed between indoor and outdoor athletes. To control for multiple cofounders (the season, latitude, and Asian/Caucasian race) simultaneously, we constructed a multivariate meta-regression model, which estimated a serum vitamin D concentration lower by 4.446 ng/mL in indoor athletes. While a multivariate model suggests that outdoor training is associated with slightly higher vitamin D concentrations when controlling for the season, latitude, and Asian/Caucasian race, the type of training has a numerically and clinically small impact. This suggests that vitamin D levels and the need for supplementation should not be decided based on training type alone.
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Affiliation(s)
- Maria Bârsan
- Department of Occupational Medicine, 'Iuliu Hațieganu' University of Medicine and Pharmacy Cluj-Napoca, 400347 Cluj-Napoca, Romania
| | - Vlad-Florin Chelaru
- Faculty of Medicine, 'Iuliu Hațieganu' University of Medicine and Pharmacy Cluj-Napoca, 400347 Cluj-Napoca, Romania
| | - Armand-Gabriel Râjnoveanu
- Department of Occupational Medicine, 'Iuliu Hațieganu' University of Medicine and Pharmacy Cluj-Napoca, 400347 Cluj-Napoca, Romania
| | - Ștefan Lucian Popa
- 2nd Medical Department, 'Iuliu Hațieganu' University of Medicine and Pharmacy Cluj-Napoca, 400347 Cluj-Napoca, Romania
| | - Andreea-Iulia Socaciu
- Department of Occupational Medicine, 'Iuliu Hațieganu' University of Medicine and Pharmacy Cluj-Napoca, 400347 Cluj-Napoca, Romania
| | - Andrei-Vlad Bădulescu
- Faculty of Medicine, 'Iuliu Hațieganu' University of Medicine and Pharmacy Cluj-Napoca, 400347 Cluj-Napoca, Romania
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Savolainen L, Timpmann S, Mooses M, Medijainen L, Tõnutare L, Ross F, Lellsaar M, Piir A, Zilmer M, Unt E, Ööpik V. Vitamin D Supplementation Has No Impact on Cardiorespiratory Fitness, but Improves Inflammatory Status in Vitamin D Deficient Young Men Engaged in Resistance Training. Nutrients 2022; 14:nu14245302. [PMID: 36558461 PMCID: PMC9787541 DOI: 10.3390/nu14245302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/09/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022] Open
Abstract
Data on the effect of vitamin D (Vit-D) supplementation on cardiorespiratory fitness (VO2max) are conflicting. A possible source of discrepancies in the literature is the heterogeneity in baseline Vit-D status among participants in previous studies. The main objectives of the present study were to assess the impact of Vit-D supplementation on VO2max and inflammatory status in Vit-D deficient young healthy men. Participants (n = 39, baseline serum Vit-D level < 50 nmol/L) were quasi-randomly assigned to one of the two groups, which, in a double-blind manner, supplemented their diet daily with either Vit-D (8000 IU; VD) or placebo (PLC) and concomitantly performed a 12-week supervised resistance training program. During the 12-week intervention, serum Vit-D concentrations increased 3.9-fold (p < 0.001) in the VD group while no changes occurred in the PLC group. Baseline VO2max did not differ in the two groups and remained unchanged during the intervention. Serum interleukin-10/tumour necrosis factor alpha ratio increased significantly (30%, p = 0.007; effect size 0.399) in VD but not in PLC group. In conclusion, 12-week Vit-D supplementation increases serum 25(OH)D levels and improves inflammatory status, but has no impact on VO2max in Vit-D deficient young men engaged in resistance training.
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Affiliation(s)
- Lauri Savolainen
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Saima Timpmann
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Martin Mooses
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Luule Medijainen
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Lisette Tõnutare
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Frederik Ross
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Märt Lellsaar
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
| | - Anneli Piir
- Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu, 50090 Tartu, Estonia
| | - Mihkel Zilmer
- Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu, 50090 Tartu, Estonia
| | - Eve Unt
- Department of Cardiology, Institute of Clinical Medicine, University of Tartu, 50090 Tartu, Estonia
- Department of Sport Medicine and Rehabilitation, Institute of Clinical Medicine, University of Tartu, 50090 Tartu, Estonia
- Sport Medicine and Rehabilitation Clinic, Tartu University Hospital, 1a Puusepa St., 50406 Tartu, Estonia
| | - Vahur Ööpik
- Institute of Sport Sciences and Physiotherapy, University of Tartu, 18 Ülikooli St., 50090 Tartu, Estonia
- Correspondence: ; Tel.: +372-7-375-366
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Książek A, Zagrodna A, Słowińska-Lisowska M, Lombardi G. Relationship Between Metabolites of Vitamin D, Free 25-(OH)D, and Physical Performance in Indoor and Outdoor Athletes. Front Physiol 2022; 13:909086. [PMID: 35874521 PMCID: PMC9304810 DOI: 10.3389/fphys.2022.909086] [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: 04/01/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
The potential effects of vitamin D in athletes have received considerable attention in the literature. However, little is known about vitamin D metabolites and their association with physical performance in athletes. Therefore, the aim of our study was to determine the relationship between metabolites of vitamin D, vitamin D binding protein (VDBP), free, bioavailable 25-(OH)D, and physical fitness tests in athletes. A total of 40 indoor and outdoor players (16 judoists and 24 football players) participated in the study. Vitamin D metabolites (25-(OH)D, 24,25-(OH)2D3, 3-epi-25-(OH)D3, and 1,25-(OH)2D) were assessed using LM-MS/MS. Free 25-(OH)D concentration was evaluated by calculation using serum albumin and VDBP levels. Athletic performance was assessed using handgrip and vertical jump. Our study showed a significant correlation between vitamin D metabolites and handgrip strength and vertical jump variables in indoor players. It demonstrated a significant association between 3-epi-25-(OH)D3 and vertical jump parameters in outdoor players. The results of our study showed relationship between free, bioavailable 25-(OH)D, and vertical jump variables in indoor players. In conclusion, we provide novel information on the vitamin D metabolites and athletic performance in athletes. Based on the results of our study, we concluded that vitamin D metabolites might be involved in skeletal muscle function in relation to athletic performance.
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Affiliation(s)
- Anna Książek
- Department of Biological and Medical Basis of Sport, Faculty of Physical Education and Sports, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
- *Correspondence: Anna Książek,
| | - Aleksandra Zagrodna
- Department of Biological and Medical Basis of Sport, Faculty of Physical Education and Sports, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
| | - Małgorzata Słowińska-Lisowska
- Department of Biological and Medical Basis of Sport, Faculty of Physical Education and Sports, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
| | - Giovanni Lombardi
- Laboratory of Experimental Biochemistry & Molecular Biology, I.R.C.C.S. Istituto Ortopedico Galeazzi, Milano, Italy
- Department of Athletics, Strength and Conditioning, Poznań University of Physical Education, Poznań, Poland
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Influences of Vitamin D and Iron Status on Skeletal Muscle Health: A Narrative Review. Nutrients 2022; 14:nu14132717. [PMID: 35807896 PMCID: PMC9268405 DOI: 10.3390/nu14132717] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 12/02/2022] Open
Abstract
There is conflicting evidence of the roles vitamin D and iron have in isolation and combined in relation to muscle health. The purpose of this narrative review was to examine the current literature on the roles that vitamin D and iron have on skeletal muscle mass, strength, and function and how these nutrients are associated with skeletal muscle health in specific populations. Secondary purposes include exploring if low vitamin D and iron status are interrelated with skeletal muscle health and chronic inflammation and reviewing the influence of animal-source foods rich in these nutrients on health and performance. PubMed, Scopus, SPORT Discus, EMBAE, MEDLINE, and Google Scholar databases were searched to determine eligible studies. There was a positive effect of vitamin D on muscle mass, particularly in older adults. There was a positive effect of iron on aerobic and anaerobic performance. Studies reported mixed results for both vitamin D and iron on muscle strength and function. While vitamin D and iron deficiency commonly occur in combination, few studies examined effects on skeletal muscle health and inflammation. Isolated nutrients such as iron and vitamin D may have positive outcomes; however, nutrients within food sources may be most effective in improving skeletal muscle health.
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