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Performance Nutrition in Diverse Populations

A special issue of Nutrients (ISSN 2072-6643). This special issue belongs to the section "Sports Nutrition".

Deadline for manuscript submissions: closed (20 January 2022) | Viewed by 88579

Special Issue Editor


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Guest Editor
Department of Health and Physical Education, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB T3E 6K6, Canada
Interests: paralympic athletes; exercise-induced gastrointestinal symptoms; diet quality; dietary supplements; nutrition knowledge
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The profile of athletes participating in sport, particularly at the elite levels, is becoming increasingly diverse. Extensive research is available regarding the body’s generalized response to exercise and the related nutritional needs; however, investigation is required regarding optimization for specific demographics. A host of factors will affect how the body responds to endurance and resistance exercise loads and the recovery thereafter. Additionally, nutrient needs are highly influenced by the individual athlete’s physiology. An athlete’s traits can affect energy expenditure, macro- and micronutrient needs, fluid recommendations, thermoregulation, muscle hypertrophy, recovery, and the effectiveness of ergogenic aids, as examples. To optimize athlete health and performance, nutritional recommendations must consider a host of factors such as age, hormone levels, and health status to name a few. Traditionally, however, recommendations are broadly applied based on evidence obtained in a relatively homogenous demographic. This Special Issue of Nutrients aims to cover a broad range of topics to improve the understanding of the influence of nutritional factors on health and physical performance in diverse athlete populations.

Dr. Jill Parnell
Guest Editor

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Keywords

  • Performance nutrition
  • Nutrition for specialized athletic populations
  • Para athletes
  • Female athletes
  • Youth athletes
  • Masters athletes
  • Ergogenic aids

Published Papers (15 papers)

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Research

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8 pages, 245 KiB  
Article
Dietary Intake of Young Male Ice Hockey Players 10–13 Years of Age during a Week-Long Hockey Camp
by Tyler F. Vermeulen, Stephanie M. Boville, Alexander S. D. Gamble, Jessica L. Bigg, Devin G. McCarthy, Gregory S. Eskedjian and Lawrence L. Spriet
Nutrients 2022, 14(14), 2978; https://doi.org/10.3390/nu14142978 - 21 Jul 2022
Cited by 3 | Viewed by 1693
Abstract
This study recorded the dietary intakes of young male ice hockey players (10–13 year (yr)) for 3 consecutive days while participating in a 5-day summer hockey camp. Players were categorized as older children (OC, n = 10; 10.7 ± 0.2 yr; 37.1 ± [...] Read more.
This study recorded the dietary intakes of young male ice hockey players (10–13 year (yr)) for 3 consecutive days while participating in a 5-day summer hockey camp. Players were categorized as older children (OC, n = 10; 10.7 ± 0.2 yr; 37.1 ± 1.5 kg; 147.9 ± 2.1 cm) and young adolescents (YA, n = 10; 12.9 ± 0.1 yr; 45.2 ± 1.5 kg; 157.0 ± 2.4 cm). Players consumed their usual daily intakes. Parents recorded food intake in the mornings and evenings, while the researchers recorded food intake at camp. Energy intake was higher in both groups when compared to data for age-matched young Canadian (CDN) males (OC, 2967 ± 211 vs. 2000 kcal/day; YA, 2773 ± 91 vs. 2250 kcal/day). Carbohydrate (CHO) (OC, 11.2 ± 0.8 vs. YO, 8.9 ± 0.5 g/kg body mass/day) and protein (OC, 3.2 ± 0.3; YO, 2.4 ± 0.1 g/kg/day) intakes were higher than reported for young CDN males (CHO, 3.6 and protein, 1.0 g/kg/day) and were within the Acceptable Macronutrient Distribution Range (AMDR; CHO, 56 ± 2.3; 57.4 ± 0.8%; protein, 16.1 ± 1.0; 15.7 ± 0.7%). Fat intake was also within the AMDR in both groups (OC, 29.8 ± 1.6%; YA, 28.3 ± 1.0%). Micronutrient intake was adequate except for Vitamin D intakes that were below the recommended 15 ug/day at 6.3 ± 0.7 (OC) and 5.0 ± 1.5 ug/day (YA). In summary, energy and macronutrient intakes of the OC (10–11 yr) and YA (12–13 yr) players were high and well above the age matched CDN norms. The older children had higher energy intakes/kg body mass than the young adolescents. Higher energy intakes allowed for micronutrients intakes to be met in these young active males, except for vitamin D intake. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
12 pages, 640 KiB  
Article
Dietary Intake over a 7-Day Training and Game Period in Female Varsity Rugby Union Players
by Claire Traversa, Danielle L. E. Nyman and Lawrence L. Spriet
Nutrients 2022, 14(11), 2281; https://doi.org/10.3390/nu14112281 - 29 May 2022
Viewed by 2326
Abstract
This study estimated the daily energy intake (EI) and energy expenditure (TDEE) in female varsity rugby union players during a weekly training/game cycle. Fifteen (nine forwards, six backs) players (20.5 ± 0.4 y, 167.1 ± 1.8 cm, 74.9 ± 2.9 kg) were monitored [...] Read more.
This study estimated the daily energy intake (EI) and energy expenditure (TDEE) in female varsity rugby union players during a weekly training/game cycle. Fifteen (nine forwards, six backs) players (20.5 ± 0.4 y, 167.1 ± 1.8 cm, 74.9 ± 2.9 kg) were monitored for a 7-day period (one fitness, two heavy training, one light training, one game, and two recovery days) during their regular season. The average EI throughout the week for all 15 players was 2158 ± 87 kcal. There were no significant differences between days, but the lowest EI (1921 ± 227 kcal) occurred on the mid-week recovery day and the highest on game day (2336 ± 231 kcal). The average TDEE was 2286 ± 168 kcal (~6% > EI). The mean energy availability (EA) over the 7-day period was 31.1 ± 3.6 kcal/kg FFM/day for the group. Of the players, 14% were in the optimal EA range (>45 kcal/kg FFM/day); 34% were in the moderate range (≥30–45 kcal/kg FFM/day); and 52% had a poor EA of <30 kcal/kg FFM/day. Carbohydrate (3.38 ± 0.36 g/kg/day, 45% of EI); fat (1.27 ± 0.12 g/kg/day, 37% of EI); and protein (1.38 ± 0.12 g/kg/day, 18% of EI) consumption remained similar throughout the week (p > 0.05). The players consumed 6% less energy than they expended, providing poor to moderate EA; therefore, daily carbohydrate intake recommendations were not met. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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12 pages, 535 KiB  
Article
Dietary Intake in Law Enforcement Personnel: Occupation Is an Additional Challenge for Changing Behavior
by Kristen L. MacKenzie-Shalders, Ka Wing Lee, Charlene Wright, Joe Dulla, Angela Tsoi and Robin M. Orr
Nutrients 2022, 14(7), 1336; https://doi.org/10.3390/nu14071336 - 23 Mar 2022
Cited by 1 | Viewed by 2356
Abstract
Background: Law enforcement is a dangerous, stressful, and health-threatening occupation. This study investigated the association between demographic factors including sex, age, and types of law enforcement occupation and described self-reported barriers to healthy and enjoyable diets within a cohort of law enforcement personnel. [...] Read more.
Background: Law enforcement is a dangerous, stressful, and health-threatening occupation. This study investigated the association between demographic factors including sex, age, and types of law enforcement occupation and described self-reported barriers to healthy and enjoyable diets within a cohort of law enforcement personnel. Methods: This mixed-methods study explored cross-sectional data from the Perceived Barriers to Healthy Eating validated survey. The survey included eight questions obtaining quantitative data and two open ended question obtaining qualitative data. A framework thematic analysis using the theory of planned behavior was undertaken to describe self-reported barriers to a healthy and enjoyable dietary intake. Results: 159 participants (median age = 27 (range 19–60) years; 74% males) were surveyed. In general, demographic factors are not associated with the dietary beliefs and behavior of law enforcement personnel. Self-reported barriers (generated themes) to a healthy and enjoyable diet included individual preferences, social influences, internal drive, capacity to change and occupational influences, which broadly aligned with the theory of planned behavior. Conclusions: Dietary intake in law enforcement personnel is impacted by occupational considerations, including busy schedules, long working hours, inconsistent meal breaks, tiredness, and shift work. The study provides useful information to support dietary interventions. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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19 pages, 1812 KiB  
Article
Effect of a Four-Week Vegan Diet on Performance, Training Efficiency and Blood Biochemical Indices in CrossFit-Trained Participants
by Krzysztof Durkalec-Michalski, Adrian Domagalski, Natalia Główka, Joanna Kamińska, Damian Szymczak and Tomasz Podgórski
Nutrients 2022, 14(4), 894; https://doi.org/10.3390/nu14040894 - 20 Feb 2022
Cited by 9 | Viewed by 10764
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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18 pages, 1297 KiB  
Article
Who Is Running in the D-A-CH Countries? An Epidemiological Approach of 2455 Omnivorous, Vegetarian, and Vegan Recreational Runners—Results from the NURMI Study (Step 1)
by Katharina Wirnitzer, Mohamad Motevalli, Derrick Tanous, Gerold Wirnitzer, Claus Leitzmann, Renato Pichler, Thomas Rosemann and Beat Knechtle
Nutrients 2022, 14(3), 677; https://doi.org/10.3390/nu14030677 - 05 Feb 2022
Cited by 13 | Viewed by 3354
Abstract
Accompanied by the growing popularity of distance running, the prevalence of vegan and vegetarian diets in endurance runners has increased across the globe and especially in German-speaking (D-A-CH: Germany, Austria, Switzerland) countries. The present study aimed to investigate and compare the epidemiological characteristics [...] Read more.
Accompanied by the growing popularity of distance running, the prevalence of vegan and vegetarian diets in endurance runners has increased across the globe and especially in German-speaking (D-A-CH: Germany, Austria, Switzerland) countries. The present study aimed to investigate and compare the epidemiological characteristics associated with diet types and running behaviors of recreational endurance runners. From a total number of 7422 runners who started to fill in the online survey, 3835 runners completed the questionnaire. After data clearance, 2455 distance runners (mean age: 37 years; 56% females, 44% males) were selected as the final sample and classified as 1162 omnivores (47.4%), 529 vegetarians (21.5%), and 764 vegans (31.1%). Sociodemographic information and general characteristics in training and competition were evaluated using a questionnaire-based approach. A significant association was found between diet type and race distance (p < 0.001). In females, vegan ultra-marathoners and omnivorous half-marathoners had better individual running records among dietary groups. Sex differences in running performance had a minimizing trend with increasing race distance. Most runners reported independent race preparation (90%) over less than four months (73%). From an epidemiological viewpoint, the present findings suggest a central role of plant-based diets in running performance and behaviors among active distance runners in D-A-CH countries and that vegetarian and vegan diets are compatible with competitive running. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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15 pages, 735 KiB  
Article
Analysis and Evaluation of Nutritional Intake and Nutrition Quotient of Korean Athletes with Disabilities in the Tokyo Paralympic Games
by Bogja Jeoung and Jiyoun Kim
Nutrients 2021, 13(10), 3631; https://doi.org/10.3390/nu13103631 - 16 Oct 2021
Cited by 8 | Viewed by 3307
Abstract
This study analyzed and evaluated the nutritional intake and nutrition quotient for adults (NQ-A) among 21 disabled national athletes preparing for the Tokyo Paralympic competition. A 24-h recall nutrition survey was conducted on the second day of training and one day of the [...] Read more.
This study analyzed and evaluated the nutritional intake and nutrition quotient for adults (NQ-A) among 21 disabled national athletes preparing for the Tokyo Paralympic competition. A 24-h recall nutrition survey was conducted on the second day of training and one day of the weekend (holidays) to analyze daily nutritional intake. Dietary information was analyzed using the NQ-A questionnaire, which comprises 21 items. The athletes were divided into three groups based on the NQ-A score (High, Middle, Low). A comparative analysis of dietary intake of disabled athletes with the recommended dietary intake amount (RDA) was performed. The intake of carbohydrates (166.9%), proteins (112.3%), vitamin E (112.0%), thiamine (124.6%), riboflavin (100.2%), vitamin B6 (110.6%), vitamin B12 (120.7%), sodium (216.6%), phosphorus (118.3%), iron (146.5%), iodine (143.2%), and selenium (114.2%) was higher than the Korean-recommended amount. In particular, as the results of comparing dietary intake between the three groups showed, the low NQ-A score group had significantly lower intake compared to the %RDA for vitamin E (67.1%), C (26.3%), and Potassium (42.8%). However, with most nutrients, nutritional intake deficiency was not shown to be a problem. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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12 pages, 886 KiB  
Article
Dietary Macronutrient and Micronutrient Intake over a 7-Day Period in Female Varsity Ice Hockey Players
by Tyler F. Vermeulen, Logan A. Boyd and Lawrence L. Spriet
Nutrients 2021, 13(7), 2262; https://doi.org/10.3390/nu13072262 - 30 Jun 2021
Cited by 6 | Viewed by 3141
Abstract
This study examined the energy, macronutrient, and micronutrient intakes of female ice hockey players over a 7-d period including game, practice, and rest days. Twenty-three female varsity players (19.0 ± 1.1 yr, 167.1 ± 6.5 cm, 67.0 ± 8.0 kg) volunteered for the [...] Read more.
This study examined the energy, macronutrient, and micronutrient intakes of female ice hockey players over a 7-d period including game, practice, and rest days. Twenty-three female varsity players (19.0 ± 1.1 yr, 167.1 ± 6.5 cm, 67.0 ± 8.0 kg) volunteered for the study. Average total daily energy expenditure (TDEE) was estimated over the 7-day period. Average 7-day energy intake (EI) and TDEE were 2354 ± 353 and 2304 ± 204 kcal. The majority (n = 19) of athletes had an EI ≥ 90% of their estimated TDEE. Macronutrient intake was 52% carbohydrate (CHO), 32% fat, and 16% protein of total EI, although CHO intake was slightly below recommendations (5 g/kg BM/d) on game and practice (4.8 ± 1.4 and 4.5 g/kg BM/d) days. Game day EI was greater than practice and rest days. Recommended micronutrient intakes were not met by most athletes for iron, calcium, vitamin D, and potassium, and intakes were similar between game, practice, and rest days. In summary, the average EI for female varsity ice hockey players appeared adequate to meet their energy needs over a weekly cycle of game, practice, and rest days. However, these female athletes would benefit from increasing CHO intake on game and practice days and selecting foods that are rich in vitamins and minerals. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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15 pages, 709 KiB  
Article
Body Composition, Dietary Intake and the Risk of Low Energy Availability in Elite-Level Competitive Rhythmic Gymnasts
by María Villa, José G. Villa-Vicente, Jesus Seco-Calvo, Juan Mielgo-Ayuso and Pilar S. Collado
Nutrients 2021, 13(6), 2083; https://doi.org/10.3390/nu13062083 - 18 Jun 2021
Cited by 10 | Viewed by 4965
Abstract
The aim of this study was to analyze dietary intake and body composition in a group of elite-level competitive rhythmic gymnasts from Spain. We undertook body composition and nutritional analysis of 30 elite gymnasts, divided into two groups by age: pre-teen (9–12 years) [...] Read more.
The aim of this study was to analyze dietary intake and body composition in a group of elite-level competitive rhythmic gymnasts from Spain. We undertook body composition and nutritional analysis of 30 elite gymnasts, divided into two groups by age: pre-teen (9–12 years) (n = 17) and teen (13–18 years) (n = 13). Measures of height, weight, and bioimpedance were used to calculate body mass index and percent body fat. Energy and nutrient intakes were assessed based on 7-day food records. The two groups had similar percentages of total body fat (pre-teen: 13.99 ± 3.83% vs. teen: 14.33 ± 5.57%; p > 0.05). The energy availability values for pre-teens were above the recommended values (>40 kcal/FFM/day) 69.38 ± 14.47 kcal/FFM/day, while those for the teens were much lower (34.7 ± 7.5 kcal/FFM/day). The distribution of the daily energy intake across the macronutrients indicates that both groups ingested less than the recommended level of carbohydrates and more than the recommended level of fat. Very low intakes of calcium and vitamin D among other micronutrients were also noted. The main finding is that teenage gymnasts do not consume as much energy as they need each day, which explains their weight and development. Moreover, they are at a high risk of developing low energy availability that could negatively impact their performance and future health. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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25 pages, 761 KiB  
Article
The Sleep and Recovery Practices of Athletes
by Rónán Doherty, Sharon M. Madigan, Alan Nevill, Giles Warrington and Jason G. Ellis
Nutrients 2021, 13(4), 1330; https://doi.org/10.3390/nu13041330 - 17 Apr 2021
Cited by 22 | Viewed by 13955
Abstract
Background: Athletes maintain a balance between stress and recovery and adopt recovery modalities that manage fatigue and enhance recovery and performance. Optimal TST is subject to individual variance. However, 7–9 h sleep is recommended for adults, while elite athletes may require more quality [...] Read more.
Background: Athletes maintain a balance between stress and recovery and adopt recovery modalities that manage fatigue and enhance recovery and performance. Optimal TST is subject to individual variance. However, 7–9 h sleep is recommended for adults, while elite athletes may require more quality sleep than non-athletes. Methods: A total of 338 (elite n = 115, 74 males and 41 females, aged 23.44 ± 4.91 years; and sub-elite n = 223, 129 males and 94 females aged 25.71 ± 6.27) athletes were recruited from a variety of team and individual sports to complete a battery of previously validated and reliable widely used questionnaires assessing sleep, recovery and nutritional practices. Results: Poor sleep was reported by both the elite and sub-elite athlete groups (i.e., global PSQI score ≥5—elite 64% [n = 74]; sub-elite 65% [n = 146]) and there was a significant difference in sport-specific recovery practices (3.22 ± 0.90 vs. 2.91 ± 0.90; p < 0.001). Relatively high levels of fatigue (2.52 ± 1.32), stress (1.7 ± 1.31) and pain (50%, n = 169) were reported in both groups. A range of supplements were used regularly by athletes in both groups; indeed, whey (elite n = 22 and sub-elite n = 48) was the most commonly used recovery supplement in both groups. Higher alcohol consumption was observed in the sub-elite athletes (12%, n = 26) and they tended to consume more units of alcohol per drinking bout. Conclusion: There is a need for athletes to receive individualised support and education regarding their sleep and recovery practices. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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12 pages, 459 KiB  
Article
Risk of Low Energy Availability in National and International Level Paralympic Athletes: An Exploratory Investigation
by Kelly Pritchett, Alicia DiFolco, Savannah Glasgow, Robert Pritchett, Katy Williams, Trent Stellingwerff, Patricia Roney, Susannah Scaroni and Elizabeth Broad
Nutrients 2021, 13(3), 979; https://doi.org/10.3390/nu13030979 - 18 Mar 2021
Cited by 16 | Viewed by 3521
Abstract
(1) Background: The purpose of this study was to examine the symptoms of low energy availability (LEA) and risk of relative energy deficiency in sport (RED-S) symptoms in para-athletes using a multi-parameter approach. (2) Methods: National level para-athletes (n = 9 males, [...] Read more.
(1) Background: The purpose of this study was to examine the symptoms of low energy availability (LEA) and risk of relative energy deficiency in sport (RED-S) symptoms in para-athletes using a multi-parameter approach. (2) Methods: National level para-athletes (n = 9 males, n = 9 females) completed 7-day food and activity logs to quantify energy availability (EA), the LEA in Females Questionnaire (LEAF-Q), dual energy X-ray absorptiometry (DXA) scans to assess bone mineral density (BMD), and hormonal blood spot testing. (3) Results: Based on EA calculations, no athlete was at risk for LEA (females < 30 kcal·kg−1 FFM·day−1; and males < 25 kcal·kg−1 FFM·day−1; thresholds for able-bodied (AB) subjects). Overall, 78% of females were “at risk” for LEA using the LEAF-Q, and 67% reported birth control use, with three of these participants reporting menstrual dysfunction. BMD was clinically low in the hip (<−2 z-score) for 56% of female and 25% of male athletes (4) Conclusions: Based on calculated EA, the risk for RED-S appears to be low, but hormonal outcomes suggest that RED-S risk is high in this para-athlete population. This considerable discrepancy in various EA and RED-S assessment tools suggests the need for further investigation to determine the true prevalence of RED-S in para-athlete populations. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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19 pages, 1980 KiB  
Article
Is a Four-Week Ketogenic Diet an Effective Nutritional Strategy in CrossFit-Trained Female and Male Athletes?
by Krzysztof Durkalec-Michalski, Paulina M. Nowaczyk, Natalia Główka, Anna Ziobrowska and Tomasz Podgórski
Nutrients 2021, 13(3), 864; https://doi.org/10.3390/nu13030864 - 06 Mar 2021
Cited by 25 | Viewed by 8987
Abstract
This single-arm interventional study examined the effect of a 4-week ketogenic diet (KD) on aerobic capacity and discipline-specific performance in female (n = 11) and male (n = 11) CrossFit-trained athletes. The participants performed incremental cycling (ICT) and Fight Gone Bad [...] Read more.
This single-arm interventional study examined the effect of a 4-week ketogenic diet (KD) on aerobic capacity and discipline-specific performance in female (n = 11) and male (n = 11) CrossFit-trained athletes. The participants performed incremental cycling (ICT) and Fight Gone Bad (FGB) tests after consuming a customary diet and a KD. Pre- and post-ICT exercise blood samples were also analysed. Consuming a KD had a slight impact on aerobic capacity and no relevant effect on CrossFit-specific performance. In females, consuming a KD led to an 10.4% decrease in peak oxygen uptake during the ICT (p = 0.027) and resulted in certain alterations in haematological parameters (haemoglobin (HGB), mean corpuscular HGB, and mean corpuscular HGB concentration). Furthermore, in males, alanine aminotransferase activity increased with a simultaneous improvement in the post-ICT blood acid–base balance after consuming a KD. The pre-exercise bilirubin concentration was also elevated in the entire group after consuming a KD. In conclusion, female CrossFit-trained athletes seem to be prone to aerobic performance decrements and increased risk of developing haematological disturbances when consuming a KD. In males who consumed a KD, there was an undesirable alanine aminotransferase elevation and a small tendency towards improved acid–base status. Moreover, consuming a KD had no effect on discipline-specific performance in CrossFit-trained athletes. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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15 pages, 1400 KiB  
Article
Dietary Patterns in Runners with Gastrointestinal Disorders
by Kelly Anne Erdman, Kim Wagner Jones, Robyn F. Madden, Nancy Gammack and Jill A. Parnell
Nutrients 2021, 13(2), 448; https://doi.org/10.3390/nu13020448 - 29 Jan 2021
Cited by 8 | Viewed by 4264
Abstract
Individuals with inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and reflux frequently experience gastrointestinal symptoms (GIS), potentially enhanced by high-intensity running. Food avoidances, food choices, and GIS in runners with IBS/IBD (n = 53) and reflux (n = 37) were [...] Read more.
Individuals with inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and reflux frequently experience gastrointestinal symptoms (GIS), potentially enhanced by high-intensity running. Food avoidances, food choices, and GIS in runners with IBS/IBD (n = 53) and reflux (n = 37) were evaluated using a reliability and validity tested questionnaire. Comparisons to a control group of runners (n = 375) were made using a Fisher’s Exact test. Runners with IBS/IBD experienced the greatest amount of exercise-induced GIS followed by those with reflux. Commonly reported GIS were stomach pain/cramps (77%; 53%), bloating (52%; 50%), intestinal pain/cramps (58%; 33%), and diarrhea (58%; 39%) in IBS/IBD and reflux groups respectively. In the pre-race meal, those with IBS/IBD frequently avoided milk products (53%), legumes (37%), and meat (31%); whereas, runners with reflux avoided milk (38%), meat (36%), and high-fibre foods (33%). When considering food choices pre-race, runners with IBS/IBD chose grains containing gluten (40%), high fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) fruits (38%), and water (38%). Runners with reflux chose water (51%), grains containing gluten (37%), and eggs (31%). In conclusion, while many runners with IBS/IBD and reflux are avoiding trigger foods in their pre-race meals, they are also consuming potentially aggravating foods, suggesting nutrition advice may be warranted. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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Review

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16 pages, 2901 KiB  
Review
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
by Jingguo Cao, Siman Lei, Xiuqiang Wang and Sulin Cheng
Nutrients 2021, 13(8), 2896; https://doi.org/10.3390/nu13082896 - 23 Aug 2021
Cited by 19 | Viewed by 16301
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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17 pages, 369 KiB  
Review
Carbohydrate Considerations for Athletes with a Spinal Cord Injury
by Belinda Ruettimann, Claudio Perret, Jill A. Parnell and Joelle Leonie Flueck
Nutrients 2021, 13(7), 2177; https://doi.org/10.3390/nu13072177 - 24 Jun 2021
Cited by 10 | Viewed by 3240
Abstract
The Paralympic movement is growing in popularity, resulting in increased numbers of athletes with a spinal cord injury (SCI) competing in various sport disciplines. Athletes with an SCI require specialized recommendations to promote health and to maximize performance, as evidenced by their metabolic [...] Read more.
The Paralympic movement is growing in popularity, resulting in increased numbers of athletes with a spinal cord injury (SCI) competing in various sport disciplines. Athletes with an SCI require specialized recommendations to promote health and to maximize performance, as evidenced by their metabolic and physiological adaptations. Nutrition is a key factor for optimal performance; however, scientifically supported nutritional recommendations are limited. This review summarizes the current knowledge regarding the importance of carbohydrates (CHO) for health and performance in athletes with an SCI. Factors possibly affecting CHO needs, such as muscle atrophy, reduced energy expenditure, and secondary complications are analyzed comprehensively. Furthermore, a model calculation for CHO requirements during an endurance event is provided. Along with assessing the effectiveness of CHO supplementation in the athletic population with SCI, the evaluation of their CHO intake from the available research supplies background to current practices. Finally, future directions are identified. In conclusion, the direct transfer of CHO guidelines from able-bodied (AB) athletes to athletes with an SCI does not seem to be reasonable. Based on the critical role of CHOs in exercise performance, establishing recommendations for athletes with an SCI should be the overall objective for prospective research. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
17 pages, 684 KiB  
Review
Dietary Supplementation for Para-Athletes: A Systematic Review
by Keely A. Shaw, Gordon A. Zello, Brian Bandy, Jongbum Ko, Leandy Bertrand and Philip D. Chilibeck
Nutrients 2021, 13(6), 2016; https://doi.org/10.3390/nu13062016 - 11 Jun 2021
Cited by 6 | Viewed by 4425
Abstract
The use of dietary supplements is high among athletes and non-athletes alike, as well as able-bodied individuals and those with impairments. However, evidence is lacking in the use of dietary supplements for sport performance in a para-athlete population (e.g., those training for the [...] Read more.
The use of dietary supplements is high among athletes and non-athletes alike, as well as able-bodied individuals and those with impairments. However, evidence is lacking in the use of dietary supplements for sport performance in a para-athlete population (e.g., those training for the Paralympics or similar competition). Our objective was to examine the literature regarding evidence for various sport supplements in a para-athlete population. A comprehensive literature search was conducted using PubMed, SPORTDiscus, MedLine, and Rehabilitation and Sports Medicine Source. Fifteen studies met our inclusion criteria and were included in our review. Seven varieties of supplements were investigated in the studies reviewed, including caffeine, creatine, buffering agents, fish oil, leucine, and vitamin D. The evidence for each of these supplements remains inconclusive, with varying results between studies. Limitations of research in this area include the heterogeneity of the subjects within the population regarding functionality and impairment. Very few studies included individuals with impairments other than spinal cord injury. Overall, more research is needed to strengthen the evidence for or against supplement use in para-athletes. Future research is also recommended on performance in para-athlete populations with classifiable impairments other than spinal cord injuries. Full article
(This article belongs to the Special Issue Performance Nutrition in Diverse Populations)
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