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Micronutrient Status of Recreational Runners with Vegetarian or Non-Vegetarian Dietary Patterns.
Nebl, J, Schuchardt, JP, Ströhle, A, Wasserfurth, P, Haufe, S, Eigendorf, J, Tegtbur, U, Hahn, A
Nutrients. 2019;11(5)
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There is current debate as to whether plant-based nutrition can provide all the required nutrients in adequate amounts for athletes. The aim of this cross-sectional study was to evaluate the micronutrient status among omnivore, vegetarian and vegan recreational runners. In this study, fasting blood levels of vitamin B12, folate, vitamin D, iron, calcium, magnesium and zinc were assessed in 27 omnivores, 26 vegetarians and 28 vegans. These results showed there were no significant differences between vegan and vegetarian diets compared with the omnivore diet. Based on these results, the authors conclude a well-planned vegetarian and vegan diet, including supplementation, can meet the recreational runner’s requirements of important micronutrients. The authors suggest further research be done on a larger sample size and on athletes of differing levels of performance intensity.
Abstract
Vegetarian diets have gained popularity in sports. However, few data exist on the status of micronutrients and related biomarkers for vegetarian and vegan athletes. The aim of this cross-sectional study was to compare the micronutrient status of omnivorous (OMN, n = 27), lacto-ovo-vegetarian (LOV, n = 26), and vegan (VEG, n = 28) recreational runners. Biomarkers of vitamin B12, folate, vitamin D, and iron were assessed. Additionally, serum levels of calcium, magnesium, and zinc were examined. Lifestyle factors and supplement intake were recorded via questionnaires. About 80% of each group showed vitamin B12 adequacy with higher levels in supplement users. Mean red blood cell folate exceeded the reference range (>340 nmol/L) in all three groups (OMN: 2213 ± 444, LOV: 2236 ± 596, and VEG: 2354 ± 639 nmol/L; not significant, n.s.). Furthermore, vitamin D levels were comparable (OMN: 90.6 ± 32.1, LOV: 76.8 ± 33.7, and VEG: 86.2 ± 39.5 nmol/L; n.s.), and we found low prevalence (<20%) of vitamin D inadequacy in all three groups. Less than 30% of each group had depleted iron stores, however, iron deficiency anemia was not found in any subject. Our findings suggest that a well-planned, health-conscious lacto-ovo-vegetarian and vegan diet, including supplements, can meet the athlete's requirements of vitamin B12, vitamin D and iron.
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Quality of life of female and male vegetarian and vegan endurance runners compared to omnivores - results from the NURMI study (step 2).
Boldt, P, Knechtle, B, Nikolaidis, P, Lechleitner, C, Wirnitzer, G, Leitzmann, C, Rosemann, T, Wirnitzer, K
Journal of the International Society of Sports Nutrition. 2018;15(1):33
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Vegetarian and vegan diets are an increasingly popular choice among members of the public and recreational athletes. There is a lack of knowledge about how a vegetarian or vegan diet might affect measures of wellbeing in athletes. The aim of this study was to compare Quality of Life (QOL) scores among endurance runners following a vegetarian or vegan diet against those who include meat in their diet. A total of 281 recreational endurance runners completed a QOL questionnaire which measured physical health, psychological wellbeing, social relationships and environment. 64% of female and 47% of male respondents followed a vegetarian or vegan diet. Men tended to have higher QOL scores than women, with higher scores in physical health and psychological well-being compared to women. Diet did not affect physical health or psychological wellbeing in men or women. Adhering to an omnivorous diet slightly but significantly improved environment scores for women and social relationships scores for men. The results revealed that endurance runners had a high QOL that was not greatly affected by diet choice. The researchers suggest that adhering to a vegetarian or vegan diet can be an appropriate and equal alternative to an omnivorous diet for endurance runners.
Abstract
BACKGROUND Health-related effects of a vegetarian or vegan diet are known to support parameters positively affecting exercise performance in athletes, whereas knowledge about psyche and wellbeing is sparse. Therefore, the aim of the Nutrition and Running High Mileage (NURMI) Study (Step 2) was to compare Quality of Life (QOL) scores among endurance runners following a vegetarian or vegan diet against those who adhere to an omnivorous diet. METHODS The study was conducted following a cross-sectional design. A total of 281 recreational runners (159 women, 122 men) completed the WHOQOL-BREF questionnaire consisting of the domains physical health, psychological wellbeing, social relationships and environment, which generates scores on a scale from 4 to 20. Data analysis was performed using ANOVA. RESULTS It was found that 123 subjects followed an omnivorous diet and 158 adhered to a vegetarian/vegan diet. There were 173 runners who met the inclusion criteria ('NURMI-Runners'), among them 103 half-marathoners and 70 marathoners and ultramarathoners, as well as 108 10 km runners as control group. Overall QOL scores were high (~ 16.62 ± 1.91). Men had higher scores than women due to high scores in the physical health and psychological well-being dimensions. Adhering to an omnivorous diet affected environment scores for women and social relationships scores for men. A minor effect concerning race distance was observed in women, where half-marathoners had a higher environmental score than 10-km runners. A moderate diet×race distance interaction on environment scores was shown for men. CONCLUSIONS The results revealed that endurance runners had a high QOL regardless of the race distance or diet choice. These findings support the notion that adhering to a vegetarian or vegan diet can be an appropriate and equal alternative to an omnivorous diet. TRIAL REGISTRATION ISRCTN73074080 . Registered 12th June 2015, retrospectively registered.
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Effect of a Protein Supplement on the Gut Microbiota of Endurance Athletes: A Randomized, Controlled, Double-Blind Pilot Study.
Moreno-Pérez, D, Bressa, C, Bailén, M, Hamed-Bousdar, S, Naclerio, F, Carmona, M, Pérez, M, González-Soltero, R, Montalvo-Lominchar, MG, Carabaña, C, et al
Nutrients. 2018;10(3)
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Protein supplements are popular among athletes to improve performance and increase muscle mass. However, their effect on other aspects of health is less well known. Dietary changes can affect gut microbiota balance, with beneficial or harmful consequences for the host. This small pilot study was performed on cross-country runners whose diets were complemented with a protein supplement (whey isolate and beef hydrolysate) or maltodextrin (control) for 10 weeks. Microbiota, water content, pH, ammonia, and short-chain fatty acids (SCFAs) were analysed in faecal samples, and oxidative stress markers were measured in blood plasma and urine. Faecal pH, water content, ammonia, and SCFA concentrations did not change, indicating that protein supplementation did not increase the presence of these metabolites of fermentation. Similarly, it had no impact on plasma or urine malondialdehyde levels. Protein supplementation did however increase the abundance of the Bacteroidetes phylum and decrease the presence of health-related taxa including Roseburia, Blautia, and Bifidobacterium longum. The authors concluded that long-term protein supplementation may have a negative impact on gut microbiota. Further research is needed to establish the impact of protein supplements on gut microbiota.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Long-term protein supplementation may have a negative impact on gut microbiota.
- Further research is needed to establish the impact of protein supplements on gut microbiota and whether there is a differential impact between protein from animal and plant sources.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
This is a very interesting study that is relevant to athletic populations.
Clinical practice applications:
Potentially there is a role for probiotics / prebiotics when increasing protein intake (particularly of animal origin) to maintain microbiota diversity and prevent ensuing health complications.
Considerations for future research:
Further, larger scale, research is needed to understand whether the same effect of protein supplementation would be seen with plant-based proteins or whether this is unique to animal based protein supplementation. For example, is the hydrolysation of the proteins to account for the largest effect or could a whole food protein, i.e. not hydrolysed, elicit the same effects?
Also, is this effect seen in other sports, e.g. non-endurance. What about the effect under different conditions e.g. energy deficit vs. energy excess?
Abstract
Nutritional supplements are popular among athletes to improve performance and physical recovery. Protein supplements fulfill this function by improving performance and increasing muscle mass; however, their effect on other organs or systems is less well known. Diet alterations can induce gut microbiota imbalance, with beneficial or deleterious consequences for the host. To test this, we performed a randomized pilot study in cross-country runners whose diets were complemented with a protein supplement (whey isolate and beef hydrolysate) (n = 12) or maltodextrin (control) (n = 12) for 10 weeks. Microbiota, water content, pH, ammonia, and short-chain fatty acids (SCFAs) were analyzed in fecal samples, whereas malondialdehyde levels (oxidative stress marker) were determined in plasma and urine. Fecal pH, water content, ammonia, and SCFA concentrations did not change, indicating that protein supplementation did not increase the presence of these fermentation-derived metabolites. Similarly, it had no impact on plasma or urine malondialdehyde levels; however, it increased the abundance of the Bacteroidetes phylum and decreased the presence of health-related taxa including Roseburia, Blautia, and Bifidobacterium longum. Thus, long-term protein supplementation may have a negative impact on gut microbiota. Further research is needed to establish the impact of protein supplements on gut microbiota.
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Effects of Low Versus Moderate Glycemic Index Diets on Aerobic Capacity in Endurance Runners: Three-Week Randomized Controlled Crossover Trial.
Durkalec-Michalski, K, Zawieja, EE, Zawieja, BE, Jurkowska, D, Buchowski, MS, Jeszka, J
Nutrients. 2018;10(3)
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During athletic performance, adequate amounts of carbohydrates are required to prolong the onset of fatigue. Research on whether the glycaemic index (GI) of ingested carbohydrates effects performance has been explored but has produced equivocal results. The aim of this randomised crossover study was to assess the effect of low- and moderate- GI diets on the aerobic capacity and endurance performance in 21 runners. Participants consumed a low- and moderate- GI, high carbohydrate and nutrient balanced diets for three weeks each with a two-week washout period. Aerobic capacity and body composition were measured at the beginning and end of each diet period through various athletic performance tests. This study found that after a low-GI, high-carbohydrate diet, improvements were seen in time to exhaustion and running performance. Gas exchange was improved by both diets. The low-GI carbohydrate diet helped athletes to maintain a more stable blood glucose concentration during exertion tests. Based on these results the authors suggest considering GI when planning a diet for performance athletes, and also urge further research be completed to better understand the effects of long-term GI diets with regards to exercise performance.
Abstract
The glycemic index (GI) of ingested carbohydrates may influence substrate oxidation during exercise and athletic performance. Therefore, the aim of this study was to assess the effect of low- and moderate-GI three-week diets on aerobic capacity and endurance performance in runners. We conducted a randomized crossover feeding study of matched diets differing only in GI (low vs. moderate) in 21 endurance-trained runners. Each participant consumed both, low- (LGI) and moderate-GI (MGI) high-carbohydrate (~60%) and nutrient-balanced diets for three weeks each. At the beginning and end of each diet, participants had their aerobic capacity and body composition measured and performed a 12-min running test. After LGI, time to exhaustion during incremental cycling test (ICT) and distance covered in the 12-min run were significantly increased. The MGI diet led to an increase in maximal oxygen uptake ( V ˙ O₂max), but no performance benefits were found after the MGI diet. The LGI and MGI diets improved time and workload at gas exchange threshold (GET) during ICT. The results indicate that a three-week high-carbohydrate LGI diet resulted in a small but significant improvement in athletic performance in endurance runners. Observed increase in V ˙ O₂max on MGI diet did not affect performance.
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Effect of protein and carbohydrate solutions on running performance and cognitive function in female recreational runners.
Gui, Z, Sun, F, Si, G, Chen, Y
PloS one. 2017;12(10):e0185982
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Research has shown that consuming a carbohydrate-electrolyte solution (CES) during endurance exercise can improve performance, delay fatigue and ameliorate post-exercise cognitive dysfuction when compared with a noncaloric placebo (PLA). The addition of protein to the CES (CPES) has been suggested to increase these benefits however the current data is limited. The aim of this crossover study was to investigate whether the added protein to a CES would improve exercise performance and cognitive function in 11 female recreational marathon runners. Participants were randomised to consume one of the three solutions (CES, CPES or PLA) every 2.5km during a 21km run, with a 28-day interval, and their VO2max and cognitive function were recorded after the run. This study showed that CES improved endurance performance compared with PLA, however adding protein to the CES did not provide any additional performance benefit. The CPES solution did benefit visual motor speed compared to PLA, but no differences were found in the other cognitive function tests.
Abstract
This study compared the effects of a carbohydrate-electrolyte-protein solution (CEPS, 2% protein plus 4% carbohydrate), carbohydrate-electrolyte solution (CES, 6% carbohydrate), and noncaloric sweetened placebo (PLA) on both 21-km running performance and cognitive function. Eleven female recreational endurance runners performed a 21-km time-trial running on three occasions, separated by at least 28 days. In a randomized cross-over design, they ingested CEPS, CES, or PLA at a rate of 150 mL every 2.5 km with no time feedback. A cognitive function test was performed before and after the run. Participants ingested approximately 24 g/h carbohydrate plus 12 g/h protein in CEPS trial, and 36 g/h carbohydrate in CES trial during each 21-km trial. Time to complete the time-trial was slightly shorter (P < 0.05) during CES (129.6 ± 8.8 min) than PLA (134.6 ± 11.5 min), with no differences between CEPS and the other two trials. The CEPS trial showed higher composite of visual motor speed than the PLA trial (P < 0.05). In conclusion, CES feedings might improve 21-km time-trial performance in female recreational runners compared with a PLA. However, adding protein to the CES provided no additional time-trial performance benefit. CEPS feeding during prolonged exercise could benefit visual motor speed compared to PLA alone, but no differences in the performance of the other cognitive function tests were found.
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Physiologic and behavioral indicators of energy deficiency in female adolescent runners with elevated bone turnover.
Barrack, MT, Van Loan, MD, Rauh, MJ, Nichols, JF
The American journal of clinical nutrition. 2010;92(3):652-9
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Young female runners are more likely to have a low bone mass for their age. It is thought that this might be partly due to them using more energy (calories) than they consume. This study looked at the relationship between nutrition intake and biomarkers of bone turnover in young female runners. Participants were competitive cross-country runners, aged 14-17. The girls ate their usual diet and kept a food diary for a week, to allow the researchers to analyse their nutritional intakes. Runners that had an elevated bone turnover consumed significantly less calories and calcium than the runners with a normal bone turnover. They were also more likely to have a lower body mass, fewer menstrual cycles, lower oestrogen and vitamin D levels, lower BMI and lower bone mass. The authors concluded that nutritional support to increase energy and calcium intake, and vitamin D levels may improve bone growth in young female runners.
Abstract
BACKGROUND Female adolescent runners have an elevated prevalence of low bone mass for agemdashan outcome that may be partially due to inadequate energy intake. OBJECTIVE The objective was to evaluate diet, menstrual history, serum hormone concentrations, and bone mass in female adolescent runners with normal or abnormal bone turnover. DESIGN Thirty-nine cross-country runners (age: 15.7 plusmn 0.2 y) participated in the study, which included a 7-d dietary assessment with the use of a food record and daily 24-h dietary recalls; serum measures of insulin-like growth factor I, estradiol, leptin, parathyroid hormone, progesterone, triiodothyronine, 25-hydroxycholecalciferol, bone-specific alkaline phosphatase (BAP), and cross-linked C-telopeptides of type I collagen (CTX); an evaluation of height, weight, bone mass, and body composition with the use of dual-energy X-ray absorptiometry; and a questionnaire to assess menses and sports participation. Age- and sex-specific BAP and CTX concentrations of at least the 97th percentile and no greater than the third percentile, respectively, were considered abnormal. RESULTS All abnormal BAP and CTX concentrations fell within the elevated ( ge 97%) range. Runners with an elevated bone turnover (EBT) (n = 13) had a lower body mass, fewer menstrual cycles in the past year, lower estradiol and 25-hydroxycholecalciferol concentrations, and a higher prevalence of body mass index lt 10% for age, vitamin D insufficiency, amenorrhea, and low bone mass. Girls with EBT consumed less than the recommended amounts of energy and had a higher prevalence of consuming lt 1300 mg Ca than did those with normal bone turnover. CONCLUSIONS Runners with EBT had a profile consistent with energy deficiency. Nutritional support to increase energy, calcium intake, and 25-hydroxycholecalciferol concentrations may improve bone mineral accrual in young runners with EBT. This trial was registered at clinicaltrials.gov as NCT01059968.