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Journal of the International Society of... 2017The International Society of Sports Nutrition (ISSN) provides an objective and critical review regarding the timing of macronutrients in reference to healthy, exercising... (Review)
Review
The International Society of Sports Nutrition (ISSN) provides an objective and critical review regarding the timing of macronutrients in reference to healthy, exercising adults and in particular highly trained individuals on exercise performance and body composition. The following points summarize the position of the ISSN:Nutrient timing incorporates the use of methodical planning and eating of whole foods, fortified foods and dietary supplements. The timing of energy intake and the ratio of certain ingested macronutrients may enhance recovery and tissue repair, augment muscle protein synthesis (MPS), and improve mood states following high-volume or intense exercise.Endogenous glycogen stores are maximized by following a high-carbohydrate diet (8-12 g of carbohydrate/kg/day [g/kg/day]); moreover, these stores are depleted most by high volume exercise.If rapid restoration of glycogen is required (< 4 h of recovery time) then the following strategies should be considered:aggressive carbohydrate refeeding (1.2 g/kg/h) with a preference towards carbohydrate sources that have a high (> 70) glycemic indexthe addition of caffeine (3-8 mg/kg)combining carbohydrates (0.8 g/kg/h) with protein (0.2-0.4 g/kg/h) Extended (> 60 min) bouts of high intensity (> 70% VOmax) exercise challenge fuel supply and fluid regulation, thus carbohydrate should be consumed at a rate of ~30-60 g of carbohydrate/h in a 6-8% carbohydrate-electrolyte solution (6-12 fluid ounces) every 10-15 min throughout the entire exercise bout, particularly in those exercise bouts that span beyond 70 min. When carbohydrate delivery is inadequate, adding protein may help increase performance, ameliorate muscle damage, promote euglycemia and facilitate glycogen re-synthesis.Carbohydrate ingestion throughout resistance exercise (e.g., 3-6 sets of 8-12 repetition maximum [RM] using multiple exercises targeting all major muscle groups) has been shown to promote euglycemia and higher glycogen stores. Consuming carbohydrate solely or in combination with protein during resistance exercise increases muscle glycogen stores, ameliorates muscle damage, and facilitates greater acute and chronic training adaptations.Meeting the total daily intake of protein, preferably with evenly spaced protein feedings (approximately every 3 h during the day), should be viewed as a primary area of emphasis for exercising individuals.Ingestion of essential amino acids (EAA; approximately 10 g)either in free form or as part of a protein bolus of approximately 20-40 g has been shown to maximally stimulate muscle protein synthesis (MPS).Pre- and/or post-exercise nutritional interventions (carbohydrate + protein or protein alone) may operate as an effective strategy to support increases in strength and improvements in body composition. However, the size and timing of a pre-exercise meal may impact the extent to which post-exercise protein feeding is required.Post-exercise ingestion (immediately to 2-h post) of high-quality protein sources stimulates robust increases in MPS.In non-exercising scenarios, changing the frequency of meals has shown limited impact on weight loss and body composition, with stronger evidence to indicate meal frequency can favorably improve appetite and satiety. More research is needed to determine the influence of combining an exercise program with altered meal frequencies on weight loss and body composition with preliminary research indicating a potential benefit.Ingesting a 20-40 g protein dose (0.25-0.40 g/kg body mass/dose) of a high-quality source every three to 4 h appears to most favorably affect MPS rates when compared to other dietary patterns and is associated with improved body composition and performance outcomes.Consuming casein protein (~ 30-40 g) prior to sleep can acutely increase MPS and metabolic rate throughout the night without influencing lipolysis.
Topics: Athletic Performance; Body Composition; Dietary Carbohydrates; Dietary Proteins; Energy Metabolism; Feeding Behavior; Glycogen; Humans; Nutritional Requirements; Physical Endurance; Resistance Training; Societies; Sports Nutritional Sciences; Time Factors
PubMed: 28919842
DOI: 10.1186/s12970-017-0189-4 -
Nutrients Nov 2013Diet, particularly vitamin deficiency, is associated with the risk of birth defects. The aim of this review paper is to show the characteristics of common and severe... (Review)
Review
Diet, particularly vitamin deficiency, is associated with the risk of birth defects. The aim of this review paper is to show the characteristics of common and severe neural-tube defects together with congenital heart defects (CHD) as vitamin deficiencies play a role in their origin. The findings of the Hungarian intervention (randomized double-blind and cohort controlled) trials indicated that periconceptional folic acid (FA)-containing multivitamin supplementation prevented the major proportion (about 90%) of neural-tube defects (NTD) as well as a certain proportion (about 40%) of congenital heart defects. Finally the benefits and drawbacks of three main practical applications of folic acid/multivitamin treatment such as (i) dietary intake; (ii) periconceptional supplementation; and (iii) flour fortification are discussed. The conclusion arrived at is indeed confirmation of Benjamin Franklin's statement: "An ounce of prevention is better than a pound of care".
Topics: Diet; Dietary Supplements; Flour; Folic Acid; Folic Acid Deficiency; Food, Fortified; Heart Defects, Congenital; Humans; Neural Tube Defects
PubMed: 24284617
DOI: 10.3390/nu5114760 -
BMJ (Clinical Research Ed.) Oct 2021To examine the associations between dietary intake and tissue biomarkers of alpha linolenic acid (ALA) and risk of mortality from all causes, cardiovascular disease... (Meta-Analysis)
Meta-Analysis
Dietary intake and biomarkers of alpha linolenic acid and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of cohort studies.
OBJECTIVE
To examine the associations between dietary intake and tissue biomarkers of alpha linolenic acid (ALA) and risk of mortality from all causes, cardiovascular disease (CVD), and cancer.
DESIGN
Systematic review and meta-analysis of prospective cohort studies.
DATA SOURCES
PubMed, Scopus, ISI Web of Science, and Google Scholar to 30 April 2021.
STUDY SELECTION
Prospective cohort studies that reported the risk estimates for death from all causes, CVD, and cancer.
DATA SYNTHESIS
Summary relative risks and 95% confidence intervals were calculated for the highest versus lowest categories of ALA intake using random effects and fixed effects models. Linear and non-linear dose-response analyses were conducted to assess the dose-response associations between ALA intake and mortality.
RESULTS
41 articles from prospective cohort studies were included in this systematic review and meta-analysis, totalling 1 197 564 participants. During follow-up ranging from two to 32 years, 198 113 deaths from all causes, 62 773 from CVD, and 65 954 from cancer were recorded. High intake of ALA compared with low intake was significantly associated with a lower risk of deaths from all causes (pooled relative risk 0.90, 95% confidence interval 0.83 to 0.97, I=77.8%, 15 studies), CVD (0.92, 0.86 to 0.99, I=48.2%, n=16), and coronary heart disease (CHD) (0.89, 0.81 to 0.97, I=5.6%, n=9), and a slightly higher risk of cancer mortality (1.06, 1.02 to 1.11, I=3.8%, n=10). In the dose-response analysis, a 1 g/day increase in ALA intake (equivalent to one tablespoon of canola oil or 0.5 ounces of walnut) was associated with a 5% lower risk of all cause (0.95, 0.91 to 0.99, I=76.2%, n=12) and CVD mortality (0.95, 0.91 to 0.98, I=30.7%, n=14). The pooled relative risks for the highest compared with lowest tissue levels of ALA indicated a significant inverse association with all cause mortality (0.95, 0.90 to 0.99, I=8.2%, n=26). Also, based on the dose-response analysis, each 1 standard deviation increment in blood concentrations of ALA was associated with a lower risk of CHD mortality (0.92, 0.86 to 0.98, I=37.1%, n=14).
CONCLUSIONS
The findings show that dietary ALA intake is associated with a reduced risk of mortality from all causes, CVD, and CHD, and a slightly higher risk of cancer mortality, whereas higher blood levels of ALA are associated with a reduced risk of all cause and CHD mortality only.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO CRD42021229487.
Topics: Cardiovascular Diseases; Eating; Humans; Mortality; Neoplasms; Protective Factors; Risk Assessment; alpha-Linolenic Acid
PubMed: 34645650
DOI: 10.1136/bmj.n2213 -
Sports Health 2018Emphasis on enhancing baseball pitch velocity has become popular, especially through weighted-ball throwing. However, little is known about the physical effects or... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Emphasis on enhancing baseball pitch velocity has become popular, especially through weighted-ball throwing. However, little is known about the physical effects or safety of these programs. The purpose of this study was to examine the effects of training with weighted baseballs on pitch velocity, passive range of motion (PROM), muscle strength, elbow torque, and injury rates.
HYPOTHESIS
A 6-week weighted ball training program would result in a change in pitching biomechanical and physical characteristics.
STUDY DESIGN
Randomized controlled trial.
LEVEL OF EVIDENCE
Level 1.
METHODS
During the baseball offseason, 38 healthy baseball pitchers were randomized into a control group and an experimental group. Pitch velocity, shoulder and elbow PROM, shoulder strength, elbow varus torque, and shoulder internal rotation velocity were measured in both groups. The experimental group then performed a 6-week weighted ball throwing program 3 times per week using balls ranging from 2 to 32 ounces while the control group only used a 5-ounce regulation baseball. Both groups performed a strength training program. Measurements were then repeated after the 6-week period. Injuries were tracked over the 6-week training program and the subsequent baseball season. The effect of training with a weighted ball program was assessed using 2-way repeated-measures analysis of variance at an a priori significance level of P < 0.05.
RESULTS
Mean age, height, mass, and pretesting throwing velocity were 15.3 ± 1.2 years (range, 13-18 years), 1.73 ± 0.28 m, 68.3 ± 11 kg, and 30.3 ± 0.7 m/s, respectively. Pitch velocity showed a statistically significant increase (3.3%) in the experimental group ( P < 0.001). There was a statistically significant increase of 4.3° of shoulder external rotation in the experimental group. The overall injury rate was 24% in the experimental group. Four participants in the experimental group suffered elbow injuries, 2 during the training program and 2 in the season after training. No pitchers in the control group were injured at any time during the study.
CONCLUSION
Performing a 6-week weighted ball throwing program increased pitch velocity. However, the program resulted in increased shoulder external rotation PROM and increased injury rate.
CLINICAL RELEVANCE
Although weighted-ball training may increase pitch velocity, caution is warranted because of the notable increase in injuries and physical changes observed in this cohort.
Topics: Adolescent; Arm; Arm Injuries; Athletic Performance; Baseball; Biomechanical Phenomena; Elbow; Humans; Male; Muscle Strength; Physical Conditioning, Human; Range of Motion, Articular; Rotation; Sports Equipment; Time Factors; Torque; Elbow Injuries
PubMed: 29882722
DOI: 10.1177/1941738118779909 -
JAMA Dermatology Mar 2022
Topics: Cardiovascular Diseases; Humans; Psoriasis
PubMed: 35044422
DOI: 10.1001/jamadermatol.2021.4723 -
Obesity (Silver Spring, Md.) Feb 2016To evaluate the effects of water versus beverages sweetened with non-nutritive sweeteners (NNS) on body weight in subjects enrolled in a year-long behavioral weight loss... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To evaluate the effects of water versus beverages sweetened with non-nutritive sweeteners (NNS) on body weight in subjects enrolled in a year-long behavioral weight loss treatment program.
METHODS
The study used a randomized equivalence design with NNS or water beverages as the main factor in a trial among 303 weight-stable people with overweight and obesity. All participants participated in a weight loss program plus assignment to consume 24 ounces (710 ml) of water or NNS beverages daily for 1 year.
RESULTS
NNS and water treatments were non-equivalent, with NNS treatment showing greater weight loss at the end of 1 year. At 1 year subjects receiving water had maintained a 2.45 ± 5.59 kg weight loss while those receiving NNS beverages maintained a loss of 6.21 ± 7.65 kg (P < 0.001 for difference).
CONCLUSIONS
Water and NNS beverages were not equivalent for weight loss and maintenance during a 1-year behavioral treatment program. NNS beverages were superior for weight loss and weight maintenance in a population consisting of regular users of NNS beverages who either maintained or discontinued consumption of these beverages and consumed water during a structured weight loss program. These results suggest that NNS beverages can be an effective tool for weight loss and maintenance within the context of a weight management program.
Topics: Adult; Beverages; Body Mass Index; Body Weight; Energy Intake; Female; Humans; Longitudinal Studies; Male; Middle Aged; Non-Nutritive Sweeteners; Obesity; Water; Weight Loss
PubMed: 26708700
DOI: 10.1002/oby.21327 -
British Journal of Anaesthesia Jan 2021
Topics: Anemia; Blood Transfusion; Hemorrhage; Humans; Prospective Studies
PubMed: 32981674
DOI: 10.1016/j.bja.2020.09.009 -
Clinical Microbiology and Infection :... Oct 2018
Topics: Bacterial Vaccines; Community-Acquired Infections; Escherichia coli Infections; Humans; Urinary Tract Infections; Uropathogenic Escherichia coli; Vaccines
PubMed: 30170134
DOI: 10.1016/j.cmi.2018.08.016 -
The Journal of Nutrition Sep 2022The 2020-2025 Dietary Guidelines for Americans (2020 DGA) recommend 3 dietary patterns for Americans, including a Healthy Vegetarian Dietary Pattern (HVDP).
BACKGROUND
The 2020-2025 Dietary Guidelines for Americans (2020 DGA) recommend 3 dietary patterns for Americans, including a Healthy Vegetarian Dietary Pattern (HVDP).
OBJECTIVES
The objective of this study was to assess whether nutritionally adequate dairy-free and vegan adaptations to the HVDP can be modeled with foods already in the DGA.
METHODS
Using similar food pattern modeling procedures as the 2020 DGA, the nutrient composition of 2 alternative models-dairy-free and vegan-of the 1800-, 2000-, 2200-, and 2400-kcal/d HVDPs was assessed. The dairy food group was replaced with a dairy alternative group comprised of soy milk and soy yogurt fortified with calcium, vitamin A, and vitamin D. For the vegan model, eggs were replaced with equal proportions of vegetarian protein foods.
RESULTS
Dairy-free and vegan models required minimal changes to the HVDP. Cup-equivalents and/or ounce-equivalents of vegetables, fruits, grains, oils, and discretionary calories remained unchanged. Content of total fat, polyunsaturated fat, linoleic acid (18:2n-6), linolenic acid, iron, copper, vitamin D, riboflavin, vitamin B-12, and vitamin K increased in both models by ≥10% (all comparisons relative to the original HVDP). Choline increased ≥25% in the dairy-free models. Protein decreased 11% in both 1800-kcal/d models and 10% in both 2000-kcal/d models. Sodium, cholesterol, zinc, and phosphorus decreased across all energy levels in both models, and selenium decreased in the vegan model. Carbohydrate, fiber, saturated fat, EPA, DHA, calcium, magnesium, potassium, vitamin A, vitamin E, vitamin C, thiamin, folate, and vitamin B-6 changed ≤10%. Both models contained adequate nutrients to meet Dietary Reference Intakes (DRIs) for most age and sex groups for which 1800-, 2000-, 2200-, and 2400-kcal/d diets are appropriate. Zinc was the only nutrient below the DRI for males.
CONCLUSIONS
The dairy-free and vegan HVDP models could help adults who do not consume dairy foods and/or other animal products to meet nutrition recommendations.
Topics: Calcium; Calcium, Dietary; Diet; Diet, Vegetarian; Humans; Male; United States; United States Department of Agriculture; Vegans; Vitamin A; Vitamin D; Vitamins; Zinc
PubMed: 35485767
DOI: 10.1093/jn/nxac100