Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance

A non-invasive 13CO2 breath test detects differences in anabolic sensitivity with feeding and heavy resistance exercise in healthy young males: a randomized control trial

There are limited tools to measure anabolic sensitivity non-invasively in response to acute physiological stimuli, which represents a challenge for research in free-living settings and vulnerable populations. We tested the ability of a stable isotope breath test to detect changes in leucine oxidation (OX) and leucine retention (intake - OX) across a range of anabolic sensitivities. Healthy males ingested a beverage containing 0.25 g·kg-1 protein and 0.75 g·kg-1 carbohydrate with the leucine content enriched to 5% with L-[1-13C]leucine at rest (FED) or after a bout of resistance exercise (EXFED), with a parallel group consuming only the tracer (FAST). Concurrent primed-constant infusions of L-[5,5,5-2H3]leucine revealed high peripheral bioavailability for FED (~81%), EXFED (~80%), and FAST (~117%). After beverage ingestion, whole-body protein synthesis was greater in FED and EXFED than FAST. OX was greater in FED and EXFED than FAST, with EXFED lower than FED. Leucine retention demonstrated expected physiological differences in anabolic sensitivity (EXFED > FED > FAST). We demonstrated that a non-invasive breath test based on an amino acid (leucine) that is preferentially metabolized in peripheral (muscle) tissues can detect differences in anabolic sensitivity. Future studies could examine this test within a variety of populations experiencing muscle growth or atrophy. Novelty Bullets • An oral L-[1-13C]leucine breath test can detect greater anabolic sensitivity after feeding and resistance exercise. • This tool may be applied in growing (e.g., children) or wasting (e.g. aging) populations where invasive procedures are not possible.

Dietary Supplements Use among Athletes in Lebanon: Knowledge, Attitudes, Practices, and Correlates

Athletes are under the utmost pressure to reach excellence in their performance and achieve the desired outcomes in competitions, prompting them to use dietary supplements. Given the threats to both health and eligibility, it is crucial to observe the prevalence, sources of information, knowledge, attitudes, and practices (KAPs) among Lebanese athletes practicing their sports for at least two years. In the present paper, a cross-sectional study is performed using the snowball sampling method, in which a self-administered KAP questionnaire is used to collect data from 455 athletes (mean age: 27.4 ± 7.9 years; men: 73.1%) participating in four sports categories (ball games, combat sports, endurance sports, and weightlifting). Among the Lebanese athletes, the prevalence of dietary supplement (DS) use was 74%, where half of them had predominately used sports supplements. Athletes in Lebanon heavily rely on coaches (74%) and online sources, including webpages and social media (64%), as key information sources for DSs. The findings suggest that significant proportions of athletes show knowledge deficits and unsatisfactory attitudes towards multiple aspects related to supplementation. Moreover, education and sports type modulate the use of DSs among athletes. Furthermore, 34% reported using supplements without a recommendation from specialists, and 69% admitted to not reading the supplement's nutrition facts. This study urges the need for the regulation of concerned authorities and education programs to help overcome the existing challenges.

Fat-Free Mass Using Bioelectrical Impedance Analysis as an Alternative to Dual-Energy X-Ray Absorptiometry in Calculating Energy Availability in Female Adolescent Athletes

Energy availability (EA) is calculated by subtracting exercise energy expenditure from energy intake, adjusted for fat-free mass (FFM) obtained using accurate methods, such as dual-energy X-ray absorptiometry (DXA). Unlike DXA, the bioelectrical impedance analysis (BIA) is low in cost, simple and easy to carry out. This study aimed to test the concordance between the calculation of EA using FFM values from four BIA predictive equations and FFM obtained using DXA in female adolescent athletes (n = 94), recruited via social media. Paired Student's t test, Wilcoxon test, Lin's concordance correlation coefficient, root mean square error, limits of agreement, and mean absolute percentage error were used to evaluate agreement between the FFM values obtained by the four SF-BIA predictive equations and DXA. Regression linear analysis was used to determine the relation between FFM values obtained using DXA and the BIA predictive equations. Standardized residuals of the FFM and EA were calculated considering DXA values as reference. The most appropriate model for the FFM (limits of agreement = 4.0/-2.6 kg, root mean square error = 1.9 kg, mean absolute percentage error = 4.34%, Lin's concordance correlation coefficient = .926) and EA (limits of agreement = 2.51/4.4 kcal·kg FFM-1·day-1, root mean square error = 1.8 kcal·kg FFM-1·day-1, mean absolute percentage error 4.24%, Lin's concordance correlation coefficient = .992) was the equation with sexual maturity as a variable, while the equation with the greatest age variability was the one with the lowest agreement. FFM-BIA predictive equations can be used to calculate EA of female adolescent athletes. However, the equation should be chosen considering sex, age, and maturation status. In the case of athletes, researchers should use equations developed for this group.

Plant-based food patterns to stimulate muscle protein synthesis and support muscle mass in humans: a narrative review

The interest in a diet with a higher proportion of plant-based foods to animal-based foods is a global food pattern trend. However, there are concerns regarding adopting plants as the main dietary protein source to support muscle protein synthesis and muscle mass. These concerns are centred on three issues: lower protein bioavailability due to antinutritional compounds in plants, lower per-serve scores of protein at similar energy intake, and amino acid scores of plants being lower than optimal. We aimed here to synthesize and discuss evidence around plant protein in human nutrition focusing on the capacity of these proteins to stimulate muscle protein synthesis as a key part of gaining or maintaining muscle mass. In this review, we address the issues of plant protein quality and provide evidence for how plant proteins can be made more effective to stimulate muscle protein synthesis and support muscle mass in partial or total replacement of consumption of products of animal origin. Novelty: ● Plant proteins are known, in general, to have lower protein quality scores than animal proteins, and this may have important implications, especially for those aiming to increase their skeletal muscle mass through exercise. ● A plant-based diet has been postulated to have lower protein quality limiting MPS responses and potentially compromising exercise-induced gains in muscle mass. ● Current evidence shows that plant proteins can stimulate MPS, as can whole foods, especially when combining food groups, increasing portion sizes, and optimizing amino acid bioavailability through processing or common preparation methods.

Iron Metabolism following Twice a Day Endurance Exercise in Female Long-Distance Runners

Iron deficiency anemia (IDA) and iron deficiency (ID) are frequently observed among endurance athletes. The iron regulatory hormone hepcidin may be involved in IDA and/or ID. Endurance athletes incorporate multiple training sessions, but the influence of repeated bouts of endurance exercise within the same day on iron metabolism remains unclear. Therefore, the purpose of the present study was to investigate the influence of twice a day endurance exercise on iron metabolism, including the hepcidin level, in female long-distance runners. Thirteen female long-distance runners participated in this study. They completed the twice-a-day endurance exercise in the morning and afternoon. Blood samples were collected four times in total: at 06:00 (P0), 14:00 (P8), 20:00 (P14), and 06:00 the next day (P24). In addition to the blood variables, nutritional intake was assessed throughout the exercise day. Serum hepcidin levels were significantly elevated (compared to P0) until the following morning (P24). Moreover, dietary analysis revealed that subjects consumed a low volume of carbohydrates (<6 g/kg body mass/day). In conclusion, twice a day endurance exercise resulted in significant elevation of serum hepcidin level 24 h after completion of the exercise in female long-distance runners. Therefore, athletes with a high risk of anemia should pay attention to training frequency and nutritional intake in order to maintain optimal iron metabolism.

Prevalence and Attitudes Towards Using Protein Supplements Among Female Gym Users: An Online Survey

Background:

Protein supplements have become a widespread practice amongst athletes and gym users worldwide. However, studies on the use of protein supplements among female gym users in Saudi Arabia are lacking.

Objective:

The aim of this study was to investigate the prevalence of protein supplement usage among female gym users and their attitudes towards protein supplementation in Riyadh city, Saudi Arabia.

Methods:

In this cross-sectional study, 502 female gym users aged ≥18 years completed a structured, self-administered online questionnaire on the usage of protein supplementation. Socio- demographic information, anthropometry, health status, exercise frequency, attitudes and knowledge regarding protein supplements were obtained.

Results:

The overall prevalence rate of protein supplement use among the study respondents was 36.3%. There were significant associations between the use of protein supplements and educational level (p< 0.05), the duration of being a gym member (p< 0.05) and frequency of gym visits per week (p< 0.05). Whey protein was the predominantly used supplement (57.8%), and the reason attributed to the use of protein supplement was muscle building (53.9%). The main sources of information regarding protein supplement use included the internet (30.2%) followed by gym coaches (25.3%).

Conclusion:

Our findings demonstrated that a considerable number of females exercising in gyms use protein supplements, and most rely on unreliable sources for decision-making of protein supplements use. Nutritional education and consultations regarding protein supplement use are warranted.

Sequential Submaximal Training in Elite Male Rowers Does Not Result in Amplified Increases in Interleukin-6 or Hepcidin

Previous research investigating single bouts of exercise have identified baseline iron status and circulating concentrations of interleukin-6 (IL-6) as contributors to the magnitude of postexercise hepcidin increase. The current study examined the effects of repeated training bouts in close succession on IL-6 and hepcidin responses. In a randomized, crossover design, 16 elite male rowers completed two trials, a week apart, with either high (1,000 mg) or low (<50 mg) calcium pre-exercise meals. Each trial involved two, submaximal 90-min rowing ergometer sessions, 2.5 hr apart, with venous blood sampled at baseline; pre-exercise; and 0, 1, 2, and 3 hr after each session. Peak elevations in IL-6 (approximately 7.5-fold, p < .0001) and hepcidin (approximately threefold, p < .0001) concentrations relative to baseline were seen at 2 and 3 hr after the first session, respectively. Following the second session, concentrations of both IL-6 and hepcidin remained elevated above baseline, exhibiting a plateau rather than an additive increase (2 hr post first session vs. 2 hr post second session, p = 1.00). Pre-exercise calcium resulted in a slightly greater elevation in hepcidin across all time points compared with control (p = .0005); however, no effect on IL-6 was evident (p = .27). Performing multiple submaximal training sessions in close succession with adequate nutritional support does not result in an amplified increase in IL-6 or hepcidin concentrations following the second session in male elite rowers. Although effects of calcium intake require further investigation, athletes should continue to prioritize iron consumption around morning exercise prior to exercise-induced hepcidin elevations to maximize absorption.

A Multidisciplinary Approach to Game Day Preparation for Team Sports: A Delphi Study With Expert Consensus

ABSTRACT

Mason, BRJ, Pumpa, KL, McKune, AJ, Gill, ND, and Ball, NB. A multidisciplinary approach to game day preparation for team sports: A Delphi study with expert consensus. J Strength Cond Res 36(5): 1345-1352, 2022-The aim of this study was to identify game day preparation strategies used by performance staff to improve team sport performance and to determine consensus regarding the application and importance of these strategies. Twenty-five performance staff working in high performance or professional team sports participated in this Delphi study, which implemented 3 survey rounds. The first round sought responses to open-ended questions relating to the use of game day preparation strategies. These responses were developed into statements and recirculated (round-2 survey), with subjects asked to rate their level of agreement with each statement. The third and final survey presented revised versions of statements that did not reach a consensus in the previous round, along with new statements derived from subject responses. A thematic analysis of the open-ended responses in the first survey identified 5 key themes relating to game day preparation strategies: "exercise," "nutrition," "psychological," "technical and tactical," and "other." The round-2 survey included 38 statements across the 5 themes, with 22 reaching the consensus threshold (≥75%) for agreement. The remaining 16 statements did not reach consensus. The final survey included 18 statements (16 revised and 2 new) with 12 reaching the consensus threshold for agreement. Key preparation strategies identified in this study include structured and progressive warm-ups, strength and power-based priming sessions, individualized nutrition plans, and precooling in hot conditions. Performance staff working in similar environments should consider adopting these strategies to improve athlete or team performance.

The effects of endogenously- and exogenously-induced hyperketonemia on exercise performance and adaptation

Elevating blood ketones may enhance exercise capacity and modulate adaptations to exercise training; however, these effects may depend on whether hyperketonemia is induced endogenously through dietary carbohydrate restriction, or exogenously through ketone supplementation. To determine this, we compared the effects of endogenously- and exogenously-induced hyperketonemia on exercise capacity and adaptation. Trained endurance athletes undertook 6 days of laboratory based cycling ("race") whilst following either: a carbohydrate-rich control diet (n = 7; CHO); a carbohydrate-rich diet + ketone drink four-times daily (n = 7; Ex Ket); or a ketogenic diet (n = 7; End Ket). Exercise capacity was measured daily, and adaptations in exercise metabolism, exercise physiology and postprandial insulin sensitivity (via an oral glucose tolerance test) were measured before and after dietary interventions. Urinary β-hydroxybutyrate increased by ⁓150-fold and ⁓650-fold versus CHO with Ex Ket and End Ket, respectively. Exercise capacity was increased versus pre-intervention by ~5% on race day 1 with CHO (p < 0.05), by 6%-8% on days 1, 4, and 6 (all p < 0.05) with Ex Ket and decreased by 48%-57% on all race days (all p > 0.05) with End Ket. There was an ⁓3-fold increase in fat oxidation from pre- to post-intervention (p < 0.05) with End Ket and increased perceived exercise exertion (p < 0.05). No changes in exercise substrate metabolism occurred with Ex Ket, but participants had blunted postprandial insulin sensitivity (p < 0.05). Dietary carbohydrate restriction and ketone supplementation both induce hyperketonemia; however, these are distinct physiological conditions with contrasting effects on exercise capacity and adaptation to exercise training.

The feasibility of a crossover, randomized controlled trial design to assess the effect of probiotics and prebiotics on health of elite Swiss para-athletes: a study protocol

BACKGROUND

Spinal cord injury (SCI) may cause an autonomic imbalance in the gastrointestinal tract, leading to deficits in colonic motility, mucosal secretions, vascular tone, and an increase of intestinal barrier permeability. Autonomic denervation and factors such as age, physical activity, antibiotic use and stress may cause intestinal bacterial translocation, decreased microbiota diversity, known as gut dysbiosis and thus increase susceptibility to experiencing gastrointestinal discomfort. Probiotic treatment in individuals with SCI may normalize the gut microbiota and improve overall health. We aim to assess the feasibility of probiotic and prebiotic intervention in athletes with SCI and collect information necessary for sample size calculation of a definite trial on improving health outcomes in para-athletes.

METHODS AND ANALYSIS

Elite Swiss para-athletes (aged> 18 years), being shortlisted for the Paralympic Games 2021 in Tokyo or a member of a national team (n = 43), will be invited to participate in this single-center randomized crossover trial. Athletes suffering from chronic inflammatory bowel diseases, those currently taking antibiotics or other medication to alleviate gastro-intestinal complaints will not be eligible to be included in the study. Athletes will be randomized (1:1) to receive for 4 weeks a daily dose of either 3 g of probiotic preparation or 5 g of prebiotic (organic oat bran) supplementation in addition to usual diet, followed by a 4-week washout period or vice versa. The primary outcome is the feasibility of the study, measured by recruitment and dropout rates, feasibility of the measurements, acceptability and adherence to the intervention. Secondary outcomes include gastrointestinal health assessment, diet and training information, handgrip strength, blood diagnostic parameters, and intestinal microbiome characterization. The changes in clinically relevant secondary outcome values will be used to make a power calculation for definite trial.

DISCUSSION

This pilot trial will address two common challenges in SCI research: the difficulty to recruit enough participants for a sufficiently powered study and the ability to collect data within the limits of a realistic budget and time frame. Upon demonstrated feasibility of the intervention and study procedures, the intervention will be evaluated in a definitive controlled trial comprising a larger sample of para-athletes (elite, engaged, or recreationally active) individuals with a SCI.

TRIAL REGISTRATION

NCT04659408.

Evidence‐Based Recovery in Soccer – Low‐Effort Approaches for Practitioners

Strategies to improve recovery are widely used among soccer players at both amateur and professional levels. Sometimes, however, recovery strategies are ineffective, improperly timed or even harmful to players. This highlights the need to educate practitioners and athletes about the scientific evidence of recovery strategies as well as to provide practical approaches to address this issue. Therefore, recent surveys among soccer athletes and practitioners were reviewed to identify the recovery modalities currently in use. Each strategy was then outlined with its rationale, its physiological mechanisms and the scientific evidence followed by practical approaches to implement the modality. For each intervention, practical and particularly low-effort strategies are provided to ensure that practitioners at all levels are able to implement them. We identified numerous interventions regularly used in soccer, i.e., sleep, rehydration, nutrition, psychological recovery, active recovery, foam-rolling/massage, stretching, cold-water immersion, and compression garments. Nutrition and rehydration were classified with the best evidence, while cold-water immersion, compression garments, foam-rolling/massage and sleep were rated with moderate evidence to enhance recovery. The remaining strategies (active recovery, psychological recovery, stretching) should be applied on an individual basis due to weak evidence observed. Finally, a guide is provided, helping practitioners to decide which intervention to implement. Here, practitioners should rely on the evidence, but also on their own experience and preference of the players.

Olympic Cycle Comparison of the Nutritional and Cardiovascular Health Status of an Elite-Level Female Swimmer: Case Study Report from Slovenia

Monitoring the many aspects that are crucial to an athlete’s performance progress is vital for further training planning and for the development of performance and the sport. We evaluated a four-year change (2018 vs. 2022) in the current nutritional and cardiovascular health status of the most successful elite-level female swimmer in Slovenia. Body composition and dietary intake were assessed using dual-energy X-ray absorptiometry and a standardized food questionnaire. The concentration of blood lipids, blood pressure, and serum micronutrients (B₁₂, 25(OH)D), potassium, calcium, phosphorus, magnesium, and iron) were measured. The four-year comparison showed an improved body composition status (i.e., increased body mass and decreased body fat (percentage and mass), increased lean soft tissue and total bone mineral density (BMD) (i.e., significantly decreased BMD of a left femoral neck and increased BMD of a spine and head)). We also measured an improvement in the cardiovascular health status of some markers (i.e., decreased total cholesterol, triglycerides, and blood pressure but increased low-density lipoprotein cholesterol), most likely due to the differences in assessed dietary intake (i.e., lower carbohydrate intake, higher total and saturated fat intake, and lower sodium intake). Notably, nutrient intakes that are generally of concern (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), vitamin B₁₂ and D, calcium, iron, and zinc (except for fiber intake)) were all within recommended ranges. However, the athlete’s vitamin K and potassium intake were not adequate. Furthermore, in 2018, the athlete did not consume dietary supplements, while she now regularly uses several dietary supplements, including EPA and DHA omega-3, vitamin D, multivitamins, carbohydrate powder, and sports drink. Moreover, from the micronutrient serum, only iron levels deviated from the reference values (37 μmol/L vs. 10.7–28.6 μmol/L). The presented screening example using valid, sensitive, and affordable methods and with rapid organizational implementation may be a viable format for regular monitoring.

COVID-19 Impact on the Sport Sector Economy and Athletic Performance

As COVID-19 continues to impact global health, and educational, financial, commercial institutions, sport, in particular, has not been spared [...]

Efficacy of Nutritional Strategies on the Improvement of the Performance and Health of the Athlete: A Systematic Review

Evidence shows that the use of food strategies can impact health, but a clear consensus about how the effects of different food strategies impact improvement in the athlete’s performance and health remain unclear. This study evaluated how food strategies, specifically intermittent fasting and a ketogenic diet affect health and performance in healthy athletes. Study selection for this review was based on clinical trial studies analyzing changes in performance and health in athletes. The Pubmed, Web of Science, PEDro, Dialnet, Scopus, CINAHL, ProQuest, Medline and Cochrane databases were searched. The Physiotherapy Evidence Database (PEDro) scale, PEDro Internal Validity Scale (IVS) and Standard Quality Assessment Criteria for Evaluating Primary Research Papers from a variety of fields (QUALSYT) checklists were used to evaluate the risk of bias of the included studies. Articles were selected based on criteria concerning the effectiveness of nutritional strategies on athletes’ performance; articles should be randomized clinical trials (RCTs) or uncontrolled clinical trials; they should be human studies and they should have been published less than 7 years ago. A total of 15 articles were evaluated, 8 randomised clinical trials and 7 non-randomized clinical studies, with 411 participants who satisfied our inclusion criteria and were included in this review. The results of the study showed intermittent fasting and time-restricted feeding as strategies that produce health benefits. On the other hand, the ketogenic diet did not reach an appropriate consensus. The articles presented a medium level of methodological quality in the PEDro scale, low quality in IVS scale and high quality in QUALSYT scale. Despite the lack of studies analyzing changes in the performance and health of athletes after the use of different nutritional strategies, intermittent fasting and time-restricted feeding should be considered since they seem to be effective, and further studies are necessary.

Is RED-S in athletes just another face of malnutrition?

BACKGROUND & AIMS

Relative energy deficiency syndrome in sport (RED-S) can impair the function of several body systems, resulting in short and long-term threats to athletes' health and performance. Research showed that these health and performance problems are often unrecognized, and the treatment is not adequate. The retrospective study presented in this paper aims to determine the prevalence of RED-S-related symptoms in a sample of Slovenian competitive athletes from various sports.

METHODS

We performed retrospective research based on a database of 150 athletes, aged from 14 to 34, who had nutritional assessments as a part of their medical examination. Data were collected, refined and statistical analysis was performed. 77 women and 73 men were included; 113 were classified as young athletes (14-21 years) and 37 as elite athletes (more than 21 years).

RESULTS

The majority (87%) of the athletes demonstrated at least one health-related symptom described by the RED-S-model; only 9% female and 18% male did not have any symptoms of RED-S. The number of different body systems with the compromised function was significantly higher (p < 0.001) in female athletes (2.9 ± 0.2) in comparison to male athletes (1.6 ± 0.1). For other health-related symptoms, there are statistically significant differences between young and elite athletes (p = 0.03), between female and male athletes (p = 0.02) and between young and elite female athletes (p = 0.01). When comparing groups by the number of all RED-S related symptoms, female athletes were more affected (p = 0.02). According to the RED-S CAT tool, the majority of athletes (64%) were classified in the yellow group, 7% of athletes have severe health and performance problems and fulfil criteria for the red group, and only 29% were classified in the green group.

CONCLUSIONS

A high prevalence of RED-S-related symptoms in our sample competitive athletes indicates the high prevalence of nutrition-related medical problems in young and elite athletes. Therefore, it is necessary to incorporate nutritional risk screenings as a part of regular medical examinations of athletes. In addition, appropriate treatments for competitive athletes should be readily accessible, even for young athletes. It seems that the youth athlete population is the most endangered for developing malnutrition-related health problems. At the same time, we urgently need a more specific and simple nutritional screening tool that will allow us to identify athletes at nutritional risk or athletes who have RED-S.

Brazilian Guidelines for Nutrition in Cystic Fibrosis

OBJECTIVE

To develop a scientific consensus on nutrition in cystic fibrosis.

METHODS

Sixteen coordinators elaborated relevant questions on nutritional therapy in cystic fibrosis, which were divided into six sections: nutritional assessment, nutritional recommendations, nutritional intervention, dietary counseling, special situations and enzyme replacement, and gastrointestinal manifestations. Two to three specialists in the field were responsible for each section and obtaining answers formulated based on standardized bibliographic searches. The available literature was searched in the PubMed®/MEDLINE database, after training and standardization of search strategies, to write the best level of evidence for the questions elaborated. Issues related to disagreement were discussed until a consensus was reached among specialists, based on the current scientific literature.

RESULTS

Forty-two questions were prepared and objectively answered, resulting in a consensus of nutritional therapy in cystic fibrosis.

CONCLUSION

This work enabled establishing a scientific consensus for nutritional treatment of cystic fibrosis patients.

Non-Pharmacological Treatments for Insulin Resistance: Effective Intervention of Plant-Based Diets—A Critical Review

Plant-based diets are becoming increasingly popular. Vegetarian diets are better for the environment and exhibit health benefits. A correctly balanced plant-based diet is appropriate at every stage of life. Compared to omnivores, vegetarians consume more fruits and vegetables, more fibre, vitamins C and E, magnesium and less saturated fats. In general, they have better nutrition knowledge, and they are slimmer, healthier and live longer than omnivores. It also seems that following a plant-based diet prevents the onset of chronic diseases such as cardiovascular diseases, hypertension, type 2 diabetes, obesity and some cancers. Food intake has a key influence on insulin resistance. Consumption of calorie-rich and highly processed foods, meats and sweetened beverages is a characteristic element of Western diets. They promote and elevate insulin resistance and type 2 diabetes. In contrast, intake of pulses and exclusion of meats as well as animal products bring significant benefits to vegetarian diets. According to studies, vegetarians and vegans have better blood parameters, including better glucose, insulin, total cholesterol, and LDL cholesterol levels. Their homeostatic model assessment for insulin resistance (HOMA-IR) test results are also better. More plant-based foods and fewer animal foods in a diet result in lower insulin resistance and a lower risk of prediabetes and type 2 diabetes. The aim of the study was to investigate the effect of plant-based diets on insulin resistance. In this review, we focused on presenting the positive effects of vegetarian and vegan diets on insulin resistance while showing possible clinical applications of plant-based diets in the treatment and prevention of modern-age diseases. Current and reliable publications meeting the requirements of Evidence-Based Medicine (EBM) were taken into account in this review.

Effects of Three Different Modes of Resistance Training on Appetite Hormones in Males With Obesity

Purpose

This study explored the effect of three different modes of resistance training on appetite hormones [leptin, ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), and peptide tyrosine–tyrosine (PYY)], cardiometabolic and anthropometric measures in males with obesity.

Methods

Forty-four males with obesity (age: 27.5 ± 9.4 yrs.; mean weight: 93.2 ± 2.2 kg, body mass index: 32.9 ± 1.2 kg/m²) were randomized to traditional resistance training (TRT, n = 11), circuit resistance training (CRT, n = 11), interval resistance training (IRT, n = 11) or control (C, n = 11) groups. All resistance training groups received 50 min of supervised training per session, three days per week, for 12 weeks. Measurements were taken at baseline and after 12 weeks of training.

Results

Plasma levels of leptin, ghrelin, CCK, and PYY decreased significantly in all three different modalities of resistance training groups when compared to the control group (p < 0.05). GLP-1 increased significantly in both CRT and IRT groups compared to TRT and C groups (p < 0.05). Glucose-dependent insulinotropic polypeptide decreased significantly in CRT and IRT groups compared to the C group (p < 0.05). Adiponectin levels increased significantly in all resistance training groups compared to the C group (p < 0.05).

Conclusion

Overall, CRT and IRT protocols had the greatest impact on appetite hormones compared to individuals who engaged in TRT or did not exercise (C).

Carbohydrate Intake Practices and Determinants of Food Choices During Training in Recreational, Amateur, and Professional Endurance Athletes: A Survey Analysis

Carbohydrate (CHO) intake during exercise can optimize endurance performance. However, there is limited information regarding fueling practices of endurance athletes during training. Accordingly, an anonymous German-language online survey was circulated examining the determinants of CHO choices, and intake practices among runners, triathletes, and cyclists during training. Survey questions included predefined answers, and a Likert scale with response of CHO food choice intakes from 1 = never to 5 = always. 1,081 endurance participants (58.0% male, 68.6% aged 18–39 years) of varying competitive levels were included in the analysis. Overall, most participants consumed a combination of commercial sport nutrition products and everyday foods (67.4%, n = 729) with their primary reason that food-first was preferred, but in some exercise scenarios, commercial sport nutrition products were deemed more convenient (61.3%, n = 447). Participants consuming commercial sport nutrition products only (19.3%, n = 209) most often valued their ease of intake during exercise (85.2%, n = 178). Among those consuming everyday foods only (13.2%, n = 143), the most common reason was the perceived importance of eating wholesome foods/natural ingredients (84.6%, n = 121). Between the most frequently consumed CHO sources during training at low-to-moderate intensities (n = 1032), sports drinks (mean ± SD; 2.56 ± 1.33) were consumed significantly more often than bananas (2.27 ± 1.14, p &lt; 0.001), with no significant difference in intake frequency between bananas and traditional muesli/fruit/energy bars (2.25 ± 1.14, p = 0.616). Whereas during high intensities (n = 1,077), sports drinks (3.31 ± 1.51) were significantly more often consumed than gels (2.79 ± 1.37), and gels significantly more often than energy bars (2.43 ± 1.28), all commercial sport nutrition products (all, p &lt; 0.001). Overall, 95.1% (n = 1028) of all participants consumed CHO during training at all exercise intensities, with males (n = 602; 2.35 ± 0.70) consuming significantly more often commercial sport nutrition products than females (n = 424; 2.14 ± 0.79, p &lt; 0.001); females consumed significantly more often everyday foods than males (1.66 ± 0.47 vs. 1.54 ± 0.42, p &lt; 0.001). Most participants used mixed CHO forms during low-to-moderate (87.9%), and high exercise intensities (94.7%). 67.6% (n = 731) of all participants reported guiding their CHO intake rates during training by gut feeling. These large-scale survey findings suggest a preference of endurance participants’ CHO intake during training in liquid form independent of exercise intensities and offer novel insights into CHO intake practices to guide sports nutrition strategies and education.

Maltodextrin-Based Carbohydrate Oral Rinsing and Exercise Performance: Systematic Review and Meta-Analysis

Background

Carbohydrates are an important fuel for optimal exercise performance during moderate- and high-intensity exercise; however, carbohydrate ingestion during high-intensity exercise may cause gastrointestinal upset. A carbohydrate oral rinse is an alternative method to improve exercise performance in moderate- to high-intensity exercise with a duration of 30–75 min. This is the first systematic review and meta-analysis to comprehensively examine the isolated effect of maltodextrin-based rinsing on exercise performance.

Objective

The objective of this review was to establish the effect of a maltodextrin-based carbohydrate oral rinse on exercise performance across various modes of exercise. Furthermore, a secondary objective was to determine the effects of moderators [(1) participant characteristics; (2) oral rinse protocols; (3) exercise protocol (i.e. cycling, running etc.) and (4) fasting] on exercise performance while using a maltodextrin-based, carbohydrate oral rinse.

Methods

Five databases (MEDLINE, PsycINFO, Embase, SPORTDiscus and Global Health) were systematically searched for articles up to March 2021 and screened using Covidence (a systematic review management tool). A random effects robust meta-analysis and subgroup analyses were performed using Stata Statistical Software: Release 16.

Results

Thirty-five articles met the inclusion criteria and were included in the systematic review; 34 of these articles were included in the meta-analysis. When using a conventional meta-analytic approach, overall, a carbohydrate oral rinse improved exercise performance in comparison with a placebo (SMD = 0.15, 95% CI 0.04, 0.27; p = 0.01). Furthermore, when implementing an adjusted, conservative, random effects meta-regression model using robust variance estimation, overall, compared with placebo, a carbohydrate oral rinse demonstrated evidence of improving exercise performance with a small effect size (SMD = 0.17, 95% CI − 0.01, 0.34; p = 0.051).

Conclusion

This systematic review and meta-analysis demonstrates that a maltodextrin-based carbohydrate oral rinse can improve exercise performance. When comparing the two meta-analytic approaches, although non-significant, the more robust, adjusted, random effects meta-regression model demonstrated some evidence of a maltodextrin-based carbohydrate oral rinse improving exercise performance overall.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-022-01658-3.

Evaluating the Effects of Increased Protein Intake on Muscle Strength, Hypertrophy and Power Adaptations with Concurrent Training: A Narrative Review

Concurrent training incorporates dual exercise modalities, typically resistance and aerobic-based exercise, either in a single session or as part of a periodized training program, that can promote muscle strength, mass, power/force and aerobic capacity adaptations for the purposes of sports performance or general health/wellbeing. Despite multiple health and exercise performance-related benefits, diminished muscle hypertrophy, strength and power have been reported with concurrent training compared to resistance training in isolation. Dietary protein is well-established to facilitate skeletal muscle growth, repair and regeneration during recovery from exercise. The degree to which increased protein intake can amplify adaptation responses with resistance exercise, and to a lesser extent aerobic exercise, has been highly studied. In contrast, much less focus has been directed toward the capacity for protein to enhance anabolic and metabolic responses with divergent contractile stimuli inherent to concurrent training and potentially negate interference in muscle strength, power and hypertrophy. This review consolidates available literature investigating increased protein intake on rates of muscle protein synthesis, hypertrophy, strength and force/power adaptations following acute and chronic concurrent training. Acute concurrent exercise studies provide evidence for the significant stimulation of myofibrillar protein synthesis with protein compared to placebo ingestion. High protein intake can also augment increases in lean mass with chronic concurrent training, although these increases do not appear to translate into further improvements in strength adaptations. Similarly, the available evidence indicates protein intake twice the recommended intake and beyond does not rescue decrements in selective aspects of muscle force and power production with concurrent training.

Bioavailability, Efficacy, Safety, and Regulatory Status of Creatine and Related Compounds: A Critical Review

In 2011, we published a paper providing an overview about the bioavailability, efficacy, and regulatory status of creatine monohydrate (CrM), as well as other “novel forms” of creatine that were being marketed at the time. This paper concluded that no other purported form of creatine had been shown to be a more effective source of creatine than CrM, and that CrM was recognized by international regulatory authorities as safe for use in dietary supplements. Moreover, that most purported “forms” of creatine that were being marketed at the time were either less bioavailable, less effective, more expensive, and/or not sufficiently studied in terms of safety and/or efficacy. We also provided examples of several “forms” of creatine that were being marketed that were not bioavailable sources of creatine or less effective than CrM in comparative effectiveness trials. We had hoped that this paper would encourage supplement manufacturers to use CrM in dietary supplements given the overwhelming efficacy and safety profile. Alternatively, encourage them to conduct research to show their purported “form” of creatine was a bioavailable, effective, and safe source of creatine before making unsubstantiated claims of greater efficacy and/or safety than CrM. Unfortunately, unsupported misrepresentations about the effectiveness and safety of various “forms” of creatine have continued. The purpose of this critical review is to: (1) provide an overview of the physiochemical properties, bioavailability, and safety of CrM; (2) describe the data needed to substantiate claims that a “novel form” of creatine is a bioavailable, effective, and safe source of creatine; (3) examine whether other marketed sources of creatine are more effective sources of creatine than CrM; (4) provide an update about the regulatory status of CrM and other purported sources of creatine sold as dietary supplements; and (5) provide guidance regarding the type of research needed to validate that a purported “new form” of creatine is a bioavailable, effective and safe source of creatine for dietary supplements. Based on this analysis, we categorized forms of creatine that are being sold as dietary supplements as either having strong, some, or no evidence of bioavailability and safety. As will be seen, CrM continues to be the only source of creatine that has substantial evidence to support bioavailability, efficacy, and safety. Additionally, CrM is the source of creatine recommended explicitly by professional societies and organizations and approved for use in global markets as a dietary ingredient or food additive.

Design of Motion Detection Device in Sports Based on Deep Learning of Internet of Things

With the improvement of people's income levels in recent years, people have gradually begun to pay more attention to health, and the number of exercise and fitness people has increased year by year. People are gradually willing to pay for sports and fitness, increase sports consumption, and promote the development of the sports and fitness industry. This article aims to study the deep learning based on the Internet of things to make people aware of the importance of sports. Not loving sports is a major problem that contemporary people need to overcome. This article proposes how to design a motion detection device in sports based on deep learning of the Internet of things. Based on the calculation of the economic volume of the deep learning of the Internet of things and the questionnaire survey method, it can be seen that, in today's globalization, although everyone knows the importance of sports, they are unwilling to practice it and would rather spend more time on the Internet. The experimental results of this article show that more than 50% of college students are very interested in sports and fitness, but the actual use is less than 30%, which is not optimistic. In social surveys, this number will be even lower, with only 14% of people interested in sports. Big data is like a "double-edged sword." It not only displays the user's exercise data in front of everyone through the built-in sensors of the mobile phone, but also manages their physical condition through these. How to use the strengths of sports applications at the same time properly disposing of private information is a part of the next development of sports applications that must be faced.

Dietary Supplements for Athletic Performance in Women: Beta-Alanine, Caffeine, and Nitrate

Beta-alanine, caffeine, and nitrate are dietary supplements generally recognized by the sport and exercise science community as evidence-based ergogenic performance aids. Evidence supporting the efficacy of these supplements, however, is greatly skewed due to research being conducted primarily in men. The physiological differences between men and women, most notably in sex hormones and menstrual cycle fluctuations, make generalizing male data to the female athlete inappropriate, and potentially harmful to women. This narrative review outlines the studies conducted in women regarding the efficacy of beta-alanine, caffeine, and nitrate supplementation for performance enhancement. Only nine studies on beta-alanine, 15 on caffeine, and 10 on nitrate in healthy women under the age of 40 years conducted in normoxia conditions were identified as relevant to this research question. Evidence suggests that beta-alanine may lower the rate of perceived exertion and extend training bouts in women, leading to greater functional adaptations. Studies of caffeine in women suggest the physiological responder status and caffeine habituation may contribute to caffeine's efficacy, with a potential plateau in the dose-response relationship of performance enhancement. Nitrate appears to vary in influence based on activity type and primary muscle group examined. However, the results summarized in the limited literature for each of these three supplements provide no consensus on dosage, timing, or efficacy for women. Furthermore, the literature lacks considerations for hormonal status and its role in metabolism. This gap in sex-based knowledge necessitates further research on these ergogenic supplements in women with greater considerations for the effects of hormonal status.

Considerations in the Care of Athletes With Type 1 Diabetes Mellitus

Type 1 diabetes mellitus is an autoimmune disease caused by affected individuals’ autoimmune response to their own pancreatic beta-cell. It affects millions of people worldwide. Exercise has numerous health and social benefits for patients with type 1 diabetes mellitus; however, careful management of blood glucose is crucial to minimize the risk of hypoglycemia and hyperglycemia. Anaerobic and aerobic exercises cause different glycemic responses during and after exercise, each of which will affect athletes’ ability to reach their target blood glucose ranges. The optimization of the patient’s macronutrient consumption, especially carbohydrates, the dosage of basal and short-acting insulin, and the frequent monitoring of blood glucose, will enable athletes to perform at peak levels while reducing their risk of dysglycemia. Despite best efforts, hypoglycemia can occur. Recognition of symptoms and rapid treatment with either fast-acting carbohydrates or glucagon is important. Continuous glucose monitoring devices have become more widely used in preventing hypoglycemia.

Recovery Strategies in Endurance Athletes

In order to achieve optimal performance, endurance athletes need to implement a variety of recovery strategies that are specific to their training and competition. Recovery is a multidimensional process involving physiological, psychological, emotional, social, and behavioral aspects. The purpose of the study was to examine current implementation, beliefs, and sources of information associated with recovery strategies in endurance athletes. Participants included 264 self-identified endurance athletes (male = 122, female = 139) across 11 different sports including placing top three overall in competition (n = 55) and placing in the top three in their age group or division (n = 113) during the past year. Endurance athletes in the current study preferred hydration, nutrition, sleep, and rest in terms of use, belief, and effectiveness of the recovery strategy. Female endurance athletes use more recovery strategies for training than males (p = 0.043, d = 0.25), but not in competition (p = 0.137, d = 0.19). For training, top three finishers overall (p &lt; 0.001, d = 0.61) and by division (p &lt; 0.001, d = 0.57), used more recovery strategies than those placing outside the top three. Similar findings were reported for competition in top three finishers overall (p = 0.008, d = 0.41) and by division (p &lt; 0.001, d = 0.45). These athletes are relying on the people around them such as coaches (48.3%) and fellow athletes (47.5%) along with websites (32.7%) for information and recommendations. Endurance athletes should be educated on other strategies to address the multidimensionality of recovery. These findings will be useful for healthcare professionals, practitioners, and coaches in understanding recovery strategies with endurance athletes.

Gut Microbiome and Metabolome Variations in Self-Identified Muscle Builders Who Report Using Protein Supplements

Muscle builders frequently consume protein supplements, but little is known about their effect on the gut microbiota. This study compared the gut microbiome and metabolome of self-identified muscle builders who did or did not report consuming a protein supplement. Twenty-two participants (14 males and 8 females) consumed a protein supplement (PS), and seventeen participants (12 males and 5 females) did not (No PS). Participants provided a fecal sample and completed a 24-h food recall (ASA24). The PS group consumed significantly more protein (118 ± 12 g No PS vs. 169 ± 18 g PS, p = 0.02). Fecal metabolome and microbiome were analyzed by using untargeted metabolomics and 16S rRNA gene sequencing, respectively. Metabolomic analysis identified distinct metabolic profiles driven by allantoin (VIP score = 2.85, PS 2.3-fold higher), a catabolic product of uric acid. High-protein diets contain large quantities of purines, which gut microbes degrade to uric acid and then allantoin. The bacteria order Lactobacillales was higher in the PS group (22.6 ± 49 No PS vs. 136.5 ± 38.1, PS (p = 0.007)), and this bacteria family facilitates purine absorption and uric acid decomposition. Bacterial genes associated with nucleotide metabolism pathways (p < 0.001) were more highly expressed in the No PS group. Both fecal metagenomic and metabolomic analyses revealed that the PS group’s higher protein intake impacted nitrogen metabolism, specifically altering nucleotide degradation.

Theacrine does not enhance physical performance or training status over 8 weeks

Fatigue is a condition that may affect physical performance during training sessions. Consequently, this will impact training performance and will also affect the performance of the individual in the long term. Caffeine is extensively used to counteract fatigue; however, it contains several side effects. Theacrine might be used as an alternative to caffeine, providing the same benefits without the side effects. The current study aimed to investigate the effects of 8 weeks of supplementation with theacrine on physical performance and training status of young amateur athletes. Twenty-two subjects were divided into two groups – Theacrine Group (T) and Placebo Group (P) – and evaluated before and after the intervention period. Evaluations included physical tests and hormonal values of insulin like growth factor (IGF)-I and IGF binding protein (IGFBP)-3, used as markers of training status. Results demonstrated that theacrine was not capable of promoting benefits regarding the physical performance of the subjects. It also had no effects on serum secretion of IGF-I and its binding protein, IGFBP-3. Therefore, the findings of this study do not support the use of theacrine to increase physical performance.

The Impact of Sodium Alginate Hydrogel on Exogenous Glucose Oxidation Rate and Gastrointestinal Comfort in Well-Trained Runners

Purpose

The purpose of this study is to quantify the effect of adding sodium alginate and pectin to a carbohydrate (CHO) beverage on exogenous glucose (ExGluc) oxidation rate compared with an isocaloric CHO beverage.

Methods

Following familiarization, eight well-trained endurance athletes performed four bouts of prolonged running (105 min; 71 ± 4% of VO₂max) while ingesting 175 mL of one of the experimental beverages every 15 min. In randomized order, participants consumed either 70 g^.h⁻¹ of maltodextrin and fructose (10% CHO; NORM), 70 g^.h⁻¹ of maltodextrin, fructose, sodium alginate, and pectin (10% CHO; ENCAP), 180 g^.h⁻¹ of maltodextrin, fructose, sodium alginate, and pectin (26% CHO; HiENCAP), or water (WAT). All CHO beverages had a maltodextrin:fructose ratio of 1:0.7 and contained 1.5 g^.L⁻¹ of sodium chloride. Total substrate oxidation, ExGluc oxidation rate, blood glucose, blood lactate, serum non-esterified fatty acid (NEFA) concentration, and RPE were measured for every 15 min. Every 30 min participants provided information regarding their gastrointestinal discomfort (GID).

Results

There was no significant difference in peak ExGluc oxidation between NORM and ENCAP (0.63 ± 0.07 and 0.64 ± 0.11 g^.min⁻¹, respectively; p > 0.5), both of which were significantly lower than HiENCAP (1.13 ± 0.13 g^.min⁻¹, p < 0.01). Both NORM and HiENCAP demonstrated higher total CHO oxidation than WAT from 60 and 75 min, respectively, until the end of exercise, with no differences between CHO trials. During the first 60 min, blood glucose was significantly lower in WAT compared with NORM and HiENCAP, but no differences were found between CHO beverages. Both ENCAP and HiENCAP demonstrated a higher blood glucose concentration from 60–105 min than WAT, and ENCAP was significantly higher than HiENCAP. There were no significant differences in reported GID symptoms between the trials.

Conclusions

At moderate ingestion rates (i.e., 70 g^.h⁻¹), the addition of sodium alginate and pectin did not influence the ExGluc oxidation rate compared with an isocaloric CHO beverage. At very high ingestion rates (i.e., 180 g^.h⁻¹), high rates of ExGluc oxidation were achieved in line with the literature.

Loss of Skeletal Muscle Mass and Intracellular Water as Undesired Outcomes of Weight Reduction in Obese Hyperglycemic Women: A Short-Term Longitudinal Study

The current study is focused on the influence of hyperglycemia on weight loss in obese premenopausal women. Specifically, the study evaluated the impact of a six-month individualized low-calorie diet combined with moderate exercise on weight reduction and glucose metabolism in obese women with normoglycemia compared to obese women with moderate hyperglycemia. The results indicated that patients with normoglycemia achieved a successful weight loss, which was connected to a decrease in adipose tissue and reflected by diminished content of visceral fat area (VFA) and percent body fat. In contrast, weight reduction in patients with hyperglycemia was connected not only to the loss of VFA but also to undesired decrease in skeletal muscle mass as well as intracellular and total body water. These unfavorable outcomes were observed despite normalization of glucose metabolism reflected by statistically significant lowering glucose, fructosamine, advanced glycation end-products, and HOMA-IR levels. Overall, the obtained results indicate the importance of the measurement of the carbohydrate profile in obese women and the need for an early introduction of weight reduction strategies before the development of hyperglycemia.

Cardiometabolic health profile of young girls with aesthetic professions

BACKGROUND

In the literature, professions that impose body standards for daily performance are designated as non-conventional professions (i.e. models, athletes, ballet dancers), with great emphasis on the female population. More than a job, it becomes a lifestyle to those inserted in this environment, thus, thousands of children and adolescents seek inclusion and success in these professions due to financial and media gains. Such professions are associated with several health-related risk factors. The purpose of this study was to identify and compare among physical fitness levels, cardiometabolic health markers, mental health and dietary habits in non-conventional professions.

METHODS

The sample consisted of 41 female individuals aged between 14 and 24 years, allocated into four groups, control group composed by university students (UG = 11), models (MG = 11), ballet dancers (BG = 11), and athletes' group (AG = 8). Physical fitness outcomes (cardiorespiratory fitness, flexibility, maximal dynamic strength, muscular endurance and body composition); biochemical outcomes (high-density lipoprotein [HDL], low-density lipoprotein [LDL], total cholesterol [TC], fasting glucose [FG], fasting insulin [FI], C-reactive protein [CRP]), diet quality and mental health were evaluated.

RESULTS

No impairments were observed in the health markers evaluated among groups, both for health-related physical fitness and biochemical outcomes. However, low levels of bone mineral density (BMD) were observed. Even with statistically significant differences between the groups for chronological age (p = 0.002), menarche (p = 0.004), career length (p = 0.001), height (p = 0.001), body mass index (p = 0.018), waist-to-height ratio (p < 0.001), %Fat (p = 0.020), VO2peak (p = 0.020), maximal dynamic strength of knee extensors (p = 0.031) and elbow flexors (p = 0,001) and flexibility (p < 0.001), all these values are within the normal range for health.

CONCLUSION

The professions analyzed do not seem to interfere in the physical fitness and cardiometabolic health of the girls assessed. However, we identified that exposure to these profession can impair mental health (depressive symptoms in 100% of participants) and body composition (BMD 63% of participants).

Significant differences in dietary intake of NCAA Division III soccer players compared to recommended levels

Objective: This study evaluated dietary intake patterns of NCAA Division III soccer players compared to recommended levels. Participants: NCAA Division III soccer players (n = 75). Methods: Actual dietary intake was determined by the analysis of a 3-day food record. Results: Results indicate that total energy, carbohydrate, and dietary fiber intake was significantly below the recommended levels. In addition, added sugar and total fat consumption were significantly above recommended levels. Potassium, magnesium, and vitamin D levels were consumed in levels significantly below the recommended levels. Sodium, iron, and vitamin C were consumed in significantly higher levels than the recommended target. Female athletes had significantly higher intakes of added sugar, saturated fat and vitamin C compared to male athletes. Female athletes had significantly lower intakes of calcium, potassium, sodium, iron, magnesium and vitamin D compared to male athletes. Conclusion: Based on the results of the present study, increased efforts should be put into development of nutrition education programs for NCAA Division III athletes.

Intensity Dependent Effects of Interval Resistance Training on Myokines and Cardiovascular Risk Factors in Males With Obesity

OBJECTIVE

To determine the effects of different intensities of interval resistance training (IRT) protocols on the levels of select myokines (decorin, follistatin, myostatin, activin A, transforming growth factor beta-1 [TGF-β1]), and cardiometabolic and anthropometric measures in males with obesity.

METHODS

Forty-four obese males (age: 27.5 ± 9.4 yr.; height: 165.4 ± 2.8 cm; weight: 97.9 ± 2.6 kg and BMI: 35.7 ± 4.3 kg/m²) were randomly assigned to one of four groups (n=11 per group): low-intensity interval resistance training (LIIRT), moderate-intensity interval resistance training (MIIRT), high-intensity interval resistance training (HIIRT) or control (C). The LIIRT group performed 10 exercises in 3 sets of 40% (20 repetitions), the MIIRT group performed 10 exercises in three sets of 60% (13 repetitions), and the HIIRT group performed 10 exercises in three sets of 80% (10 repetitions) of one maximum repetition (1RM), which were followed with active rest of 20% of 1RM and 15 repetitions. The resistance training groups exercised ~70 min per session, 3 days per week, for 12 weeks. Measurements were taken at baseline and after 12 weeks of exercise training.

RESULTS

Baseline levels of myokines, cardiovascular risk factors, anthropometry, body composition, and cardio-respiratory fitness were not different between the four groups (p>0.05). The group x time interactions for decorin, activin A, follistatin, myostatin, and TGF-β1, total cholesterol (TC), triglyceride (TG), high-density cholesterol (HDL), low-density cholesterol (LDL), anthropometry, body composition, and cardio-respiratory fitness were statistically significant (p<0.05). There were increases in post-test values for decorin, follistatin, HDL (p<0.05) and decreases in TC, TG, TGF-β1, LDL, and myostatin levels in the LIIRT, MIIRT, and HIIRT groups compared to pretest values (p<0.05). Changes in fat mass, VO_2peak, HDL, TG, glucose, activin A, decorin were not significant in LIIRT compared to the control group, while changes in activin A, follistatin, and TFG-β1 levels were greater in HIIRT and MIIRT groups compared to the LIIRT group (p<0.05).

CONCLUSION

The LIIRT, MIIRT, and HIIRT protocols all produced beneficial changes in decorin, activin A, follistatin, myostatin, and TGF-β1 levels, and cardiometabolic risk factors, with greater effects from the MIIRT and HIIRT protocols compared to LIIRT.

Evaluation of a randomized nutrition intervention combining nutrition education and cooking workshops on dietary intakes and psychosocial determinants of performance in university football athletes

Although nutrition influences performance, many athletes, including football players, do not meet nutritional requirements for their sport. The objective of this study was to determine the impact of a nutrition intervention combining nutrition education and cooking workshops on nutrition knowledge, intention, and perceived behavioral control in the preparation of healthy meals, dietary intakes, and diet quality in male university football players. Athletes ( n = 23; age: 22 ± 1 year) were randomly assigned to an intervention (2 h/week) ( n = 13) or control group ( n = 10) over three weeks. Questionnaires were completed before (pre), immediately after (post 1), and two months after the intervention (post 2). Dietary intakes and diet quality were evaluated from three web-based 24-h dietary recalls per visit. Mixed linear models for repeated measures with Tukey’s post hoc test were performed to determine the effects of the intervention on all outcomes. There was a group by time interaction for nutrition knowledge ( p = 0.002) that was higher immediately after and two months after the intervention compared to the control group. No differences on other outcomes were observed. Combining nutrition education and cooking workshops improved nutrition knowledge, but did not affect intention and perceived behavioral control in the preparation of healthy meals, dietary intakes, and diet quality in male university football athletes.

Assessment of nutrition knowledge in division I college athletes

OBJECTIVE

Assess nutrition knowledge of Division I college athletes.

PARTICIPANTS

128 student-athletes (n = 70 female) from eight sports completed the survey in June 2018. METHODS: The survey by Calella et al (2017) was used to assess both general and sport nutrition knowledge.

RESULTS

Cases with more than 20% of responses missing were excluded (n = 3). Overall average score was 57.6% ± 18.6%. Females scored significantly (p < 0.001) better than the males (66.5% ± 16.4% versus 46.2% ± 14.7%). Participants were divided into revenue (football, ice hockey, male's basketball, women's basketball; n = 63) and non-revenue sports (field hockey, golf, rowing, soccer; n = 62) to address differences in knowledge between sports with greater versus lesser nutrition resource access. Revenue sports scored significantly (p < 0.001) worse than non-revenue sports (45.7% ± 15.2% versus 69.7% ± 13.1%).

CONCLUSIONS

Athletes appear to have low nutrition knowledge, putting them at risk for inappropriate dietary choices that could decrease ability to optimally perform and increase risk of injury.

The Ergogenic Effects of Acute Carbohydrate Feeding on Resistance Exercise Performance: A Systematic Review and Meta-analysis

BACKGROUND

Carbohydrate (CHO) ingestion has an ergogenic effect on endurance training performance. Less is known about the effect of acute CHO ingestion on resistance training (RT) performance and equivocal results are reported in the literature.

OBJECTIVE

The current systematic review and meta-analysis sought to determine if and to what degree CHO ingestion influences RT performance.

METHODS

PubMed, MEDLINE, SportDiscus, Scopus, and CINAHL databases were searched for peer-reviewed articles written in English that used a cross-over design to assess the acute effect of CHO ingestion on RT performance outcomes (e.g., muscle strength, power, and endurance) in healthy human participants compared to a placebo or water-only conditions. The Cochrane Collaboration's risk of bias tool and GRADE approaches were used to assess risk of bias and certainty of evidence, respectively. Random effects meta-analyses were performed for total training session volume and post-exercise blood lactate and glucose. Sub-group meta-analysis and meta-regression were performed for categorical (session and fast durations) and continuous (total number of maximal effort sets, load used, and CHO dose) covariates, respectively.

RESULTS

Twenty-one studies met the inclusion criteria (n = 226 participants). Pooled results revealed a significant benefit of CHO ingestion in comparison to a placebo or control for total session training volume (standardised mean difference [SMD] = 0.61). Sub-group analysis revealed a significant benefit of CHO ingestion during sessions longer than 45 min (SMD = 1.02) and after a fast duration of 8 h or longer (SMD = 0.39). Pooled results revealed elevated post-exercise blood lactate (SMD = 0.58) and blood glucose (SMD = 2.36) with CHO ingestion. Meta-regression indicated that the number of maximal effort sets, but not CHO dose or load used, moderates the effect of CHO ingestion on RT performance (beta co-efficient [b] = 0.11). Carbohydrate dose does not moderate post-exercise lactate accumulation nor do maximal effort sets completed, load used, and CHO dose moderate the effect of CHO ingestion on post-exercise blood glucose.

CONCLUSIONS

Carbohydrate ingestion has an ergogenic effect on RT performance by enhancing volume performance, which is more likely to occur when sessions exceed 45 min and where the fast duration is ≥ 8 h. Further, the effect is moderated by the number of maximal effort sets completed, but not the load used or CHO dose. Post-exercise blood lactate is elevated following CHO ingestion but may come at the expense of an extended time-course of recovery due to the additional training volume performed. Post-exercise blood glucose is elevated when CHO is ingested during RT, but it is presently unclear if it has an impact on RT performance.

PROTOCOL REGISTRATION

The original protocol was prospectively registered on the Open Science Framework (Project identifier: https://doi.org/10.17605/OSF.IO/HJFBW ).

Consumption of nutritional supplements by teenagers attending gyms supplements and exercise in teenagers

ABSTRACT Objective: To describe the supplements used by adolescents in gyms in the city of São Paulo and the factors related to their use. Methods: Participants were 1,012 adolescents of both sexes, aged between 13 and 18 years old, all of them regular regulars at gyms in the city of São Paulo. For data collection, a questionnaire was used to identify the main supplements consumed by adolescents. The chi-square test was used to verify possible associations with a significance of p<0.05. Results: The use of supplements was more frequent in the age group between 16 and 18 years, in the socioeconomic level B, and the use of these supplements was higher as the time of exercise in the gym was longer (>12 months). The amount of exercise modalities practiced in the gym was inversely associated with the use of supplements. Male adolescents consumed significantly more supplements than females, and Physical Education professionals, friends and parents were the ones who most influenced adolescents to use supplements. The main supplements used by the boys were carbohydrate gel (90.9%) and hypercaloric (94.5%). In girls it was fat burner (55.0%) and vitamins and minerals (50.0%). Conclusion: The use of supplements was common among adolescents who exercise in gyms in São Paulo and the indication was made by physical education professional.

White tea modulates antioxidant defense of endurance-trained rats

The interest in nutritional strategies that may counteract the deleterious oxidative effects induced by strenuous exercises is remarkable. Herein, the impact of white tea (Camellia sinensis) (WT), a polyphenol-rich beverage, on antioxidant status in endurance-trained rats after one session of exhaustive exercise were evaluated. Male Wistar rats were divided into groups, which received: control groups - water, and testing groups - WT1 (0.25%; w/v) or WT2 (0.5%; w/v). Drinks were consumed, ad libitum, for 5 or 10 weeks, concomitantly with the running training. Exhaustive running tests were applied before and after the experimental periods. WT intake increased the serum antioxidant capacity of rats in a dose-dependent manner (P < 0.001), which was unaccompanied by the activity of endogenous antioxidant enzymes SOD, GPx, and GR, and GSH content. Inflammatory markers in serum [IL-1β (P = 0.004) and IL-6 (P = 0.001)] could be downregulated by tea intake. In liver tissue, lower levels of lipid oxidation (P < 0.05) and improved antioxidant defenses (SOD, GPx, GR, and GSH, P < 0.05) were related to the consumption of 10.13039/100010269WT in both doses, supporting protective effects in this responsible metabolic organ. In conclusion, long-term consumption of WT could be a promising adjuvant to exercise-stress management, emphasizing its ability to regulate antioxidant responses and prevent oxidative tissue damage.

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White tea intake improved antioxidant status of blood and liver of runner rats.

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White tea intake promoted protective effect against liver lipid peroxidation after an exhaustive exercise.

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Long term white tea intake did not enhance physical performance.

Sustained Exposure to High Carbohydrate Availability Does Not Influence Iron-Regulatory Responses in Elite Endurance Athletes

This study implemented a 2-week high carbohydrate (CHO) diet intended to maximize CHO oxidation rates and examined the iron-regulatory response to a 26-km race walking effort. Twenty international-level, male race walkers were assigned to either a novel high CHO diet (MAX = 10 g/kg body mass CHO daily) inclusive of gut-training strategies, or a moderate CHO control diet (CON = 6 g/kg body mass CHO daily) for a 2-week training period. The athletes completed a 26-km race walking test protocol before and after the dietary intervention. Venous blood samples were collected pre-, post-, and 3 hr postexercise and measured for serum ferritin, interleukin-6, and hepcidin-25 concentrations. Similar decreases in serum ferritin (17-23%) occurred postintervention in MAX and CON. At the baseline, CON had a greater postexercise increase in interleukin-6 levels after 26 km of walking (20.1-fold, 95% CI [9.2, 35.7]) compared with MAX (10.2-fold, 95% CI [3.7, 18.7]). A similar finding was evident for hepcidin levels 3 hr postexercise (CON = 10.8-fold, 95% CI [4.8, 21.2]; MAX = 8.8-fold, 95% CI [3.9, 16.4]). Postintervention, there were no substantial differences in the interleukin-6 response (CON = 13.6-fold, 95% CI [9.2, 20.5]; MAX = 11.2-fold, 95% CI [6.5, 21.3]) or hepcidin levels (CON = 7.1-fold, 95% CI [2.1, 15.4]; MAX = 6.3-fold, 95% CI [1.8, 14.6]) between the dietary groups. Higher resting serum ferritin (p = .004) and hotter trial ambient temperatures (p = .014) were associated with greater hepcidin levels 3 hr postexercise. Very high CHO diets employed by endurance athletes to increase CHO oxidation have little impact on iron regulation in elite athletes. It appears that variations in serum ferritin concentration and ambient temperature, rather than dietary CHO, are associated with increased hepcidin concentrations 3 hr postexercise.

Nutritional Considerations for Injury Prevention and Recovery in Combat Sports

Sports participation is not without risk, and most athletes incur at least one injury throughout their careers. Combat sports are popular all around the world, and about one-third of their injuries result in more than 7 days of absence from competition or training. The most frequently injured body regions are the head and neck, followed by the upper and lower limbs, while the most common tissue types injured are superficial tissues and skin, followed by ligaments and joint capsules. Nutrition has significant implications for injury prevention and enhancement of the recovery process due to its effect on the overall physical and psychological well-being of the athlete and improving tissue healing. In particular, amino acid and protein intake, antioxidants, creatine, and omega-3 are given special attention due to their therapeutic roles in preventing muscle loss and anabolic resistance as well as promoting injury healing. The purpose of this review is to present the roles of various nutritional strategies in reducing the risk of injury and improving the treatment and rehabilitation process in combat sports. In this respect, nutritional considerations for muscle, joint, and bone injuries as well as sports-related concussions are presented. The injury risk associated with rapid weight loss is also discussed. Finally, preoperative nutrition and nutritional considerations for returning to a sport after rehabilitation are addressed.

A Glimpse of the Sports Nutrition Awareness in Spanish Basketball Players

Basketball is a team sport, with many fans and practitioners worldwide from all ages and levels. In all cases, players accumulate high levels of fatigue, and there is also limited time to recover between games or practices. In particular, nutrition plays a key role in optimizing performance and recovery. However, it is typical to observe erroneous nutritional behaviors among basketball players. It has been theorized that these behaviors are influenced by habits acquired based on the individual’s knowledge. Therefore, the main aim of this study was to conduct a descriptive research of the sports nutrition knowledge and practices in a sample of Spanish basketball players, from athletes under 18 years old (n = 69) to nonprofessional (n = 14) and professional adult players (n = 21). The sample was comprised of 49 men and 55 women. This was a transversal, cross-sectional, observational and descriptive study. All participants (n = 104) completed an anonymous online survey in order to analyze their sports nutrition knowledge and practices. In view of the obtained results, we can conclude that the knowledge of sport-specific nutrition in players under 18 years old, as well as non-professional and professional adult basketball players, is insufficient through all the categories and levels. The lack of professional support and time management difficulties were identified as some of the main barriers.

An Alternate Approach to Military Rations for Optimal Health and Performance

INTRODUCTION

Operational ration packs are the sole source of nutrition when military personnel cannot access fresh food and field kitchens due to deployment and training in remote and hostile locations. They should be light, durable, nutrient rich, and contain sufficient energy to ensure that the personnel can carry out the expected duties. The macronutrient composition of rations has remained relatively unchanged despite escalating concerns related to the health and operational readiness of personnel globally. Currently, the New Zealand Defence Force (NZDF) provides the personnel with a 24-hour ration pack. The aims of this study were to (1) analyse the nutrient content, cost, and weight of the NZDF-supplied ration pack and (2) develop and analyse an alternate ration pack. The alternate ration pack was designed with the intention of improving overall quality and macronutrient distribution ratio, to align with optimal health and performance outcomes.

MATERIALS AND METHODS

Nutrient and weight analyses of the NZDF and alternate ration packs were conducted using nutrition analysis software Foodworks V. 10 (Xyris software). The ration packs were costed using information from the NZDF and from commercial online shopping websites (particularly Countdown supermarket and an online shop, iHerb). Data from nutrition panels were entered into Foodworks V. 10 (Xyris software). The data underlying this article will be shared on reasonable request to the corresponding author.

RESULTS

The NZDF-supplied ration pack cost 37.00 NZD and contained an excessive amount of sugar (636 g or 46% total energy) and marginally insufficient protein (118.7 g or 9% total energy) to sustain physically active military personnel. Comparatively, the alternate ration pack was more costly (63.55 NZD) and contained significantly less sugar (74.6 g or 7.2% total energy) and exceeded protein (263.1 g or 26% total energy) requirements for physically active military personnel. Furthermore, the alternate ration pack was significantly lighter (0.71 kg) than the NZDF ration pack (1.4 kg). In summary, the alternate ration was nutritionally superior and lighter when compared to the currently supplied NZDF ration, but more expensive when purchased as a one-off.

CONCLUSIONS

This work highlights the shortcomings of currently supplied military rations packs (i.e., excessive sugar and marginally inadequate protein) and proposes a novel alternate approach to ration pack formulation. This approach would significantly reduce sugar and increase protein and fat content in military rations. Although this work indicates that the alternate approach (which would produce lighter and nutritionally superior rations) is more costly, this cost could be reduced significantly through bulk purchasing and purpose-built rations and food items. Considering these findings, field user-testing of the alternate ration pack is recommended and subsequent reformulation of guidelines for ration pack development, as appropriate.

In-Season Nutrition Strategies and Recovery Modalities to Enhance Recovery for Basketball Players: A Narrative Review

Basketball players face multiple challenges to in-season recovery. The purpose of this article is to review the literature on recovery modalities and nutritional strategies for basketball players and practical applications that can be incorporated throughout the season at various levels of competition. Sleep, protein, carbohydrate, and fluids should be the foundational components emphasized throughout the season for home and away games to promote recovery. Travel, whether by air or bus, poses nutritional and sleep challenges, therefore teams should be strategic about packing snacks and fluid options while on the road. Practitioners should also plan for meals at hotels and during air travel for their players. Basketball players should aim for a minimum of 8 h of sleep per night and be encouraged to get extra sleep during congested schedules since back-to back games, high workloads, and travel may negatively influence night-time sleep. Regular sleep monitoring, education, and feedback may aid in optimizing sleep in basketball players. In addition, incorporating consistent training times may be beneficial to reduce bed and wake time variability. Hydrotherapy, compression garments, and massage may also provide an effective recovery modality to incorporate post-competition. Future research, however, is warranted to understand the influence these modalities have on enhancing recovery in basketball players. Overall, a strategic well-rounded approach, encompassing both nutrition and recovery modality strategies, should be carefully considered and implemented with teams to support basketball players' recovery for training and competition throughout the season.

Sustainable Food Support during an Ultra-Endurance and Mindfulness Event: A Case Study in Spain

The present industrial food-production system is not suitably ecological for the environment. Mindful nutrition in sport is a relevant emergent sub-discipline that could help reduce environmental degradation. This case study describes a sustainable support diet during an ultra-endurance running (UR) event called the "Indoor Everest Challenge". This UR challenge involved attaining the altitude of Mount Everest (8849 m) in a simulated way, in less than 24 h, without using ultra-processed food and without wasting plastics. During this challenge, a male athlete (34 years, weight: 78 kg, and height: 173 cm) wore a SenseWear Armband® (BodyMedia Inc., Pittsburg, PA, USA) accelerometer on his right arm to estimate energy expenditure. To supply his nutritional requirements, the athlete consumed only specially prepared homemade and organic food. All consumption was weighed and recorded in real-time; we determined nutrients using two databases: a food composition software, Dial Alce Ingenieria® (Madrid, Spain), to measure energy and macro- and micro-nutrients, and Phenol Explorer Database® (INRA Institut National de Recherche pour l'Alimentation, Paris, France) precisely to determine polyphenolic content. Most energy intake (up to 96%) came from plant foods. We found that subject consumed 15.8 g/kg-1/d-1 or 1242 g of carbohydrates (CHO), (2.4 g/kg-1/d-1) or 190 g of proteins (P), and 10,692 mL of fluid. The total energy intake (7580 kcal) showed a distribution of 65% CHO, 10% P, and 25% lipids (L). Furthermore, this sustainable diet lead to a high antioxidant intake, specifically vitamin C (1079 mg), vitamin E (57 mg), and total polyphenols (1910 mg). This sustainable approach was suitable for meeting energy, CHO, and P recommendations for UR. Physical and mental training (mindfulness) were integrated from the specific preliminary phase to the day of the challenge. The athlete completed this challenge in 18 h with a low environmental impact. This sports event had an educational component, as it awakened curiosity towards food sustainability.

Evening Whey Protein Intake, Rich in Tryptophan, and Sleep in Elite Male Australian Rules Football Players on Training and Nontraining Days

OBJECTIVES

To investigate the effect of evening whey protein supplementation, rich in tryptophan, on sleep in elite male Australian Rules Football players.

DESIGN

Double-blinded, counterbalanced, randomized, cross-over study.

METHODS

Sleep was assessed using wrist activity monitors and sleep diaries in 15 elite male Australian Football League players on two training and nontraining days following evening consumption of an isocaloric whey protein supplement or placebo in preseason. A 5-day preintervention period was implemented to determine habitual dietary intake and baseline sleep measures. These habitual data were used to inform the daily dietary intake and timing of ingestion of the evening whey protein supplement or placebo on the intervention days. The whey protein supplement or placebo was consumed 3 hr prior to habitual bedtime.

RESULTS

Separate one-way repeated-measures analyses of covariance revealed no differences between the whey protein supplement and the placebo on sleep duration, sleep onset latency, sleep efficiency, or wake after sleep onset on either training or nontraining days.

CONCLUSIONS

Evening whey protein supplementation, rich in tryptophan, does not improve acute sleep duration or quality in elite male Australian Football League players. However, elite athletes may be able to ingest a high protein/energy intake close to bedtime without impairing sleep, which is important for athlete recovery. Future research should investigate the effect of evening protein intake, high in tryptophan, on sleep duration and quality, including sleep staging during periods of restricted sleep and in poor-sleeping athletes.

Increased carbohydrate availability effects energy and nutrient periodisation of professional male athletes from the Australian Football League

This research aimed to explore the effect of increased carbohydrate availability intervention on energy intake and distribution in professional Australian Football athletes. Six 24-h energy and macronutrient intakes were quantified (n = 19 males; age 24 ± 4 y, stature 187 ± 8 cm, mass 87 ± 9 kg) using photographic food diaries and Foodworks analyses. Energy expenditure was estimated for the same period using GeneActiv accelerometers. During 3 control days, athletes had ad libitum access to food, while the 3 intervention days increased carbohydrate availability, through greater prompting and access to carbohydrate foods. Daily energy intake was higher during intervention (185 ± 40 kJ/kg/d) compared with control (172 ± 31 kJ/kg/d; p < 0.05) but remained below estimated expenditure, and carbohydrate intake was also greater with intervention (5.0 ± 0.2 g/kg/d) than control (4.0 ± 0.2 g/kg/d; p < 0.05). Expenditure was highest during the morning, which coincided with lowest intake on all days, while the intervention was associated with greater carbohydrate intake in the morning (0.6 g/kg, p < 0.05) compared with control. Increasing availability of carbohydrate during high-load training generated a modest increase in carbohydrate and energy intake, and the intervention was most effective in improving carbohydrate intake during mornings. Novelty: Increased access and provision of carbohydrate foods increased carbohydrate consumption and energy intake on high training load days. Daily distribution of energy intake can be modified through actively promoting carbohydrate consumption.

Nutrient Intake of Wildland Firefighters During Arduous Wildfire Suppression: Macronutrient and Micronutrient Consumption

Wildland firefighters (WLFFs) perform in adverse environments making rapid adjustments to dietary needs. The National Mobile Food Services (NMFS) contract details WLFF dietary provisions on wildfire incidents.

OBJECTIVE

Determine the nutrient content of food and drink provided to and consumed by WLFFs under the NMFS contract.

METHODS

Individual (n = 122) dietary provisions and consumption was recorded during 1 workday. Nutritional analysis of items provided was compared with consumption and the recommended dietary allowance (RDA).

RESULTS

WLFFs consumed significantly (P < 0.05) fewer macronutrients than provided for calories, protein, and fat. Provided and consumed micronutrients were below the RDA for vitamins D and E, magnesium, and manganese.

CONCLUSION

Most dietary recommendations were met by NMFS provisions. Next steps include WLFF nutrition education to improve consumption and contract revisions to meet micronutrient recommendations.