Validation of web-based, multiple 24-h recalls combined with nutritional supplement intake questionnaires against nitrogen excretions to determine protein intake in Dutch elite athletes

AI nutritionist: Intelligent software as the next generation pioneer of precision nutrition

With the rapid development of information technology and artificial intelligence (AI), people have acquired the abilities and are encouraged to develop intelligent tools and software, which begins to shed light on intelligent and precise food nutrition. Despite the rapid development of such software, disparities still exist in terms of methodology, contents, and implementation strategies. Hence, a set of panoramic profiles is urgently needed to elucidate their values and guide their future development. Here a comprehensive review was conducted aiming to summarize and compare the objects, contents, intelligent algorithms, and functions realized by the already released software in current research. Consequently, 177 AI nutritionists in recent years were collected and analyzed. The advantages, limitations, and trends concerning their application scenarios were analyzed. It was found that AI nutritionists have been gradually advancing the production modes and efficiency of food recognition, dietary recording/monitoring, nutritional assessment, and nutrient/recipe recommendation. Most AI nutritionists have a relatively low level of intelligence. However, new trends combining advanced AI algorithms, intelligent sensors and big data are coming with new applications in real-time and precision nutrition. AI models concerning molecular-level behaviors are becoming the new focus to drive AI nutritionists. Multi-center and multi-level studies have also gradually been realized to be necessary.

Correlation of the Dietary Protein Intake between Those Estimated from a Short Protein Food-Recall Questionnaire and from 24-Hour Urinary Urea-Nitrogen Excretion in Stages 3-4 Chronic Kidney Disease Patients

Introduction

High protein intake may accelerate progression of chronic kidney disease (CKD). Estimation of dietary protein intake (DPI) is indispensable for management of CKD, but to achieve optimum DPI is quite challenging in routine clinical practice. We recently studied a beneficial effect of utilizing integrated care on the management of CKD at the rural community level. In that study, we created a short protein food-recall questionnaire (S-PFRQ) as a working tool to estimate DPI of the CKD patients during home visit by community health personnel. Herein, we reported the initial evaluation of the reliability of S-PFRQ from our previous study.

Objective

We compared the amount of DPI obtained from S-PFRQ with that obtained from protein-equivalent of total nitrogen appearance (PNA).

Methods

In the previous ESCORT-2 study, 914 patients with CKD stage 3 or 4, who were living in the rural area of Thailand, were prospectively followed while receiving integrated care for 36 consecutive months. During home visits by community nurses from subdistrict health centers, dietary food recall was made, recorded in S-PFRQ, and DPI was obtained. Among these, sixty patients were randomly selected, and 24-h urine was collected for urinary urea-N and estimation of PNA. A correlation was made between DPI obtained from S-PFRQ and PNA.

Results

The DPIs derived from S-PFRQ and PNA were 28.8 ± 14.8 and 39.26 ± 17.79 g/day, respectively. The mean difference and 95% CI between the 2 methods was -10.43 (-7.1 to -13.8) g/day, respectively (P < 0.001). Interclass correlation between these 2 methods was 0.24, P = 0.007. The difference between the 2 methods remained constant across different amounts of DPI.

Conclusion

The DPI estimated from S-PFRQ significantly correlated to that from PNA. However, the S-PFRQ method yielded a DPI value which was about 10 g of protein or 25% less than the PNA method. Despite this amount of difference, this S-PFRQ is user-friendly and could be used during field work as an easy and simple tool for DPI estimation in resource-limiting condition.

Potential of existing online 24-h dietary recall tools for national dietary surveys

OBJECTIVE

To describe existing online, 24-h dietary recall (24-h DR) tools in terms of functionalities and ability to tackle challenges encountered during national dietary surveys, such as maximising response rates and collecting high-quality data from a representative sample of the population, while minimising the cost and response burden.

DESIGN

A search (from 2000 to 2019) was conducted in peer-reviewed and grey literature. For each tool, information on functionalities, validation and user usability studies, and potential adaptability for integration into a new context was collected.

SETTING

Not country-specific.

PARTICIPANTS

General population.

RESULTS

Eighteen online 24-h DR tools were identified. Most were developed in Europe, for children ≥10 years old and/or for adults. Eight followed the five multiple-pass steps but used various methodologies and features. Almost all tools (except three) validated their nutrient intake estimates, but with high heterogeneity in methodologies. User usability was not always assessed, and rarely by applying real-time methods. For researchers, eight tools developed a web platform to manage the survey and five appeared to be easily adaptable to a new context.

CONCLUSIONS

Among the eighteen online 24-h DR tools identified, the best candidates to be used in national dietary surveys should be those that were validated for their intake estimates, had confirmed user and researcher usability, and seemed sufficiently flexible to be adapted to new contexts. Regardless of the tool, adaptation to another context will still require time and funding, and this is probably the most challenging step.

Relative validity and reliability of a novel diet quality assessment tool for athletes: the Athlete Diet Index

Diet quality indices are a practical, cost-effective method to evaluate dietary patterns, yet few have investigated diet quality in athletes. This study describes the relative validity and reliability of the recently developed Athlete Diet Index (ADI). Participants completed the electronic ADI on two occasions, 2 weeks apart, followed by a 4-d estimated food record (4-dFR). Relative validity was evaluated by directly comparing mean scores of the two administrations (mAdm) against scores derived from 4-dFR using Spearman's rank correlation coefficient and Bland-Altman (B-A) plots. Construct validity was investigated by comparing mAdm scores and 4-dFR-derived nutrient intakes using Spearman's coefficient and independent t test. Test-retest reliability was assessed using paired t test, intraclass correlation coefficients (ICC) and B-A plots. Sixty-eight elite athletes (18·8 (sd 4·2) years) from an Australian sporting institute completed the ADI on both occasions. Mean score was 84·1 (sd 15·2; range 42·5-114·0). The ADI had good reliability (ICC = 0·80, 95 % CI 0·69, 0·87; P < 0·001), and B-A plots (mean 1·9; level of agreement -17·8, 21·7) showed no indication of systematic bias (y = 4·57-0·03 × x) (95 % CI -0·2, 0·1; P = 0·70). Relative validity was evaluated in fifty athletes who completed all study phases. Comparison of mAdm scores with 4-dFR-derived scores was moderate (rs 0·69; P < 0·001) with no systematic bias between methods of measurement (y = 6·90-0·04 × x) (95 % CI -0·3, 0·2; P = 0·73). Higher scores were associated with higher absolute nutrient intake consistent with a healthy dietary pattern. The ADI is a reliable tool with moderate validity, demonstrating its potential for application to investigate the diet quality of athletes.

Whey protein supplementation does not accelerate recovery from a single bout of eccentric exercise

The current double blind, randomized, placebo-controlled trial with two parallel groups aimed to assess the impact of whey protein supplementation on recovery of muscle function and muscle soreness following eccentric exercise. During a 9-day period, forty recreationally active males received twice daily supplementation with either whey protein (PRO; 60 g/day) or an iso-energetic amount of carbohydrate (CON). Muscle function and soreness were assessed before, and 0, 3, 24, 48, and 72 h after performing 100 drop jumps. Recovery of isometric maximal voluntary contraction (MVC) did not significantly differ between groups (timextreatment, P = 0.56). In contrast, the recovery of isokinetic MVC at 90°·s^-1 was faster in CON as opposed to PRO (timextreatment interaction, P = 0.044). Recovery of isokinetic MVC at 180°·s^-1 was also faster in CON as opposed to PRO (timextreatment interaction, P = 0.011). Recovery of countermovement jump performance did not differ between groups (timextreatment interaction, P = 0.52). Muscle soreness, CK and CRP showed a transient increase over time (P < 0.001), with no differences between groups. In conclusion, whey protein supplementation does not accelerate recovery of muscle function or attenuate muscle soreness and inflammation during 3 days of recovery from a single bout of eccentric exercise.

Pre-Exercise Nutrition Habits and Beliefs of Endurance Athletes Vary by Sex, Competitive Level, and Diet

OBJECTIVE

The purpose of this study was to determine the self-reported beliefs and practices relating to pre-exercise nutrition intake among endurance athletes of varying ages and competitive levels and examine differences based on sex, competitive level, and habitual dietary pattern.

METHOD

An anonymous online survey was circulated internationally in English and completed by 1950 athletes of varying competitive levels (51.0% female, mean age 40.9 years [range 18:78]). Survey questions included training background, determinants of pre-exercise nutrition intake and composition, and timing relative to exercise.

RESULTS

Prior to morning exercise, 36.4%, 36.0%, and 27.6% of athletes consumed carbohydrate-containing food/drinks before almost every workout, some of the time, and never/rarely, respectively, with significant effects of sex (p < 0.001, Cramer's V (ϕ_c) = 0.15) and competitive level (p < 0.001, ϕ_c = 0.09). Nutritional intake before exercise varied based on workout duration for 47.6% of athletes, with significant effects of sex (ϕ_c = 0.15) and habitual diet (ϕ_c = 0.19), and based on workout intensity for 39.1% of athletes, with significant effects of sex (ϕ_c = 0.13) and habitual diet (ϕ_c = 0.17, all p < 0.001). Additionally, 89.0% of athletes reported using at least some type of dietary supplement (including caffeine from coffee/tea) within 1 hour before exercise.

CONCLUSIONS

Overall, nearly all factors measured relating to pre-exercise nutrition intake varied by sex, competitive level, habitual dietary pattern, and/or intensity/duration of the training session and suggest a large number of athletes may not be following current recommendations for optimizing endurance training adaptations.

Prevalence and Determinants of Fasted Training in Endurance Athletes: A Survey Analysis

Athletes may choose to perform exercise in the overnight-fasted state for a variety of reasons related to convenience, gut comfort, or augmenting the training response, but it is unclear how many endurance athletes use this strategy. We investigated the prevalence and determinants of exercise performed in the overnight-fasted state among endurance athletes using an online survey and examined differences based on sex, competitive level, and habitual dietary pattern. The survey was completed by 1,950 endurance athletes (51.0% female, mean age 40.9 ± 11.1 years). The use of fasted training was reported by 62.9% of athletes, with significant effects of sex (p < .001, Cramer’s V [φc] = 0.18, 90% CI [0.14, 0.22]), competitive level (p < .001, φc = 0.09, 90% CI [0.5, 0.13]), and habitual dietary pattern noted (p < .001, φc = 0.26, 90% CI [0.22, 0.29]). Males, nonprofessional athletes, and athletes following a low-carbohydrate, high-fat diet were most likely to perform fasted training. The most common reasons for doing so were related to utilizing fat as a fuel source (42.9%), gut comfort (35.5%), and time constraints/convenience (31.4%), whereas the most common reasons athletes avoided fasted training were that it does not help their training (47.0%), performance was worse during fasted training (34.7%), or greater hunger (34.6%). Overall, some athletes perform fasted training because they think it helps their training, whereas others avoid it because they think it is detrimental to their training goals, highlighting a need for future research. These findings offer insights into the beliefs and practices related to fasted-state endurance training.

Protein Supplementation Does Not Augment Adaptations to Endurance Exercise Training

Supplemental digital content is available in the text.

Introduction

Recently, it has been speculated that protein supplementation may further augment the adaptations to chronic endurance exercise training. We assessed the effect of protein supplementation during chronic endurance exercise training on whole-body oxidative capacity (V˙O_2max) and endurance exercise performance.

Methods

In this double-blind, randomized, parallel placebo-controlled trial, 60 recreationally active males (age, 27 ± 6 yr; body mass index, 23.8 ± 2.6 kg·m⁻²; V˙O_2max, 47 ± 6 mL·min⁻¹·kg⁻¹) were subjected to 12 wk of triweekly endurance exercise training. After each session and each night before sleep, participants ingested either a protein supplement (PRO; 28.7 g casein protein) or an isoenergetic carbohydrate placebo (PLA). Before and after the 12 wk of training, V˙O_2max and endurance exercise performance (~10-km time trial) were assessed on a cycle ergometer. Muscular endurance (total workload achieved during 30 reciprocal isokinetic contractions) was assessed by isokinetic dynamometry and body composition by dual-energy x-ray absorptiometry. Mixed-model ANOVA was applied to assess whether training adaptations differed between groups.

Results

Endurance exercise training induced an 11% ± 6% increase in V˙O_2max (time effect, P < 0.0001), with no differences between groups (PRO, 48 ± 6 to 53 ± 7 mL·min⁻¹·kg⁻¹; PLA, 46 ± 5 to 51 ± 6 mL·min⁻¹·kg⁻¹; time–treatment interaction, P = 0.50). Time to complete the time trial was reduced by 14% ± 7% (time effect, P < 0.0001), with no differences between groups (time–treatment interaction, P = 0.15). Muscular endurance increased by 6% ± 7% (time effect, P < 0.0001), with no differences between groups (time–treatment interaction, P = 0.84). Leg lean mass showed an increase after training (P < 0.0001), which tended to be greater in PRO compared with PLA (0.5 ± 0.7 vs 0.2 ± 0.6 kg, respectively; time–treatment interaction, P = 0.073).

Conclusion

Protein supplementation after exercise and before sleep does not further augment the gains in whole-body oxidative capacity and endurance exercise performance after chronic endurance exercise training in recreationally active, healthy young males.

Validity of a Food and Fluid Exercise Questionnaire for Macronutrient Intake during Exercise against Observations

Information about the accuracy of self-reported food and fluid intake during competitions is scarce. The objective of this study was to validate a previously developed food and fluid exercise questionnaire (FFEQ) against direct observations made during competitions in athletes. Fifty-eight recreational endurance athletes participating in four different running events and one cross duathlon in the Netherlands between 2015 and 2017 were recruited. The FFEQ overestimated the median energy and carbohydrate intake by 27.6 kcal/h (20.6%) and 9.25 g/h (30.8%) (p < 0.001), respectively, compared to direct observation. Reporting bias (i.e., correlation between the difference between methods and average of both methods) increased with a higher energy (r: 0.41, p < 0.01) and carbohydrate intake (r: 0.44, p < 0.01). No statistically significant difference was found between FFEQ-reported fluid intake per hour and observations (median difference: −2.93 mL, −1.1%; p = 0.48) and no fluid reporting bias was identified (r: 0.23, p = 0.08). FFEQ-reported energy (r: 0.74), carbohydrate (r: 0.74), and fluid (r: 0.85) intake was strongly correlated with the observed intake (all p-values < 0.001). In conclusion, the FFEQ accurately estimates the fluid intake on a group level during competitions in recreational athletes. Even though FFEQ overestimates the energy and carbohydrate intake, it is still a useful tool for ranking individuals based on their intake.

Validity of Dietary Assessment in Athletes: A Systematic Review

Dietary assessment methods that are recognized as appropriate for the general population are usually applied in a similar manner to athletes, despite the knowledge that sport-specific factors can complicate assessment and impact accuracy in unique ways. As dietary assessment methods are used extensively within the field of sports nutrition, there is concern the validity of methodologies have not undergone more rigorous evaluation in this unique population sub-group. The purpose of this systematic review was to compare two or more methods of dietary assessment, including dietary intake measured against biomarkers or reference measures of energy expenditure, in athletes. Six electronic databases were searched for English-language, full-text articles published from January 1980 until June 2016. The search strategy combined the following keywords: diet, nutrition assessment, athlete, and validity; where the following outcomes are reported but not limited to: energy intake, macro and/or micronutrient intake, food intake, nutritional adequacy, diet quality, or nutritional status. Meta-analysis was performed on studies with sufficient methodological similarity, with between-group standardized mean differences (or effect size) and 95% confidence intervals (CI) being calculated. Of the 1624 studies identified, 18 were eligible for inclusion. Studies comparing self-reported energy intake (EI) to energy expenditure assessed via doubly labelled water were grouped for comparison (n = 11) and demonstrated mean EI was under-estimated by 19% (-2793 ± 1134 kJ/day). Meta-analysis revealed a large pooled effect size of -1.006 (95% CI: -1.3 to -0.7; p < 0.001). The remaining studies (n = 7) compared a new dietary tool or instrument to a reference method(s) (e.g., food record, 24-h dietary recall, biomarker) as part of a validation study. This systematic review revealed there are limited robust studies evaluating dietary assessment methods in athletes. Existing literature demonstrates the substantial variability between methods, with under- and misreporting of intake being frequently observed. There is a clear need for careful validation of dietary assessment methods, including emerging technical innovations, among athlete populations.

Evaluation of dietary intake assessed by the Dutch self-administered web-based dietary 24-h recall tool (Compl-eat™) against interviewer-administered telephone-based 24-h recalls

Self-administered web-based 24-h dietary recalls (24 hR) may save a lot of time and money as compared with interviewer-administered telephone-based 24 hR interviews and may therefore be useful in large-scale studies. Within the Nutrition Questionnaires plus (NQplus) study, the web-based 24 hR tool Compl-eat™ was developed to assess Dutch participants’ dietary intake. The aim of the present study was to evaluate the performance of this tool against the interviewer-administered telephone-based 24 hR method. A subgroup of participants of the NQplus study (20–70 years, n 514) completed three self-administered web-based 24 hR and three telephone 24 hR interviews administered by a dietitian over a 1-year period. Compl-eat™ as well as the dietitians guided the participants to report all foods consumed the previous day. Compl-eat™ on average underestimated the intake of energy by 8 %, of macronutrients by 10 % and of micronutrients by 13 % as compared with telephone recalls. The agreement between both methods, estimated using Lin's concordance coefficients (LCC), ranged from 0·15 for vitamin B₁ to 0·70 for alcohol intake (mean LCC 0·38). The lower estimations by Compl-eat™ can be explained by a lower number of total reported foods and lower estimated intakes of the food groups, fats, oils and savoury sauces, sugar and confectionery, dairy and cheese. The performance of the tool may be improved by, for example, adding an option to automatically select frequently used foods and including more recall cues. We conclude that Compl-eat™ may be a useful tool in large-scale Dutch studies after suggested improvements have been implemented and evaluated.

Snap-N-Send: A valid and reliable method for assessing the energy intake of elite adolescent athletes

To ensure that elite adolescent athletes meet their unique training, growth and maturation demands, it is imperative to have access to valid measures of energy intake. Contemporary methods demand close attention-to-detail, meaning that athletes often do not fully adhere to real-time protocols. This study represents the first investigation of a real-time dietary assessment designed using a comprehensive behaviour change framework (COM-B). In a crossover design, 12 elite adolescent male rugby players recorded their energy intake via an estimated food diary (est-FD) and photography-based mobile assessment ('Snap-n-Send'), combined with a 24-h dietary recall interview. Two 4-day assessment periods were divided into three separate recording environments: 96 h free-living and researcher-observed; 72 h free-living and 10 h researcher-observed. Assessment periods were one month apart. All foods and beverages were provided and weighed by the research team to quantify actual intakes. 'Snap-n-Send' reported a small mean bias for under-reporting across 96 h (-0.75 MJ day^-1; 95% confidence interval [CI] for bias = -5.7% to -2.2%, p < .001), 72 h (-0.76 MJ day^-1; 95% CI for bias = -5.6% to -2.1%, p = .004) and 10 h (-0.72 MJ day^-1; 95% CI for bias = -8.1% to -0.1%; p = .067) environments. The est-FD reported a moderate mean bias for under-reporting across 96 h (-2.89 MJ day^-1; 95% CI for bias = -17.9% to -10.2%; p < .001), 72 h (-2.88 MJ day^-1; 95% CI for bias = -17.9% to -10.1%; p < .001) and 10 h (-2.52 MJ day^-1;-26.1% to -5.3%; p = .023) environments. Results evidence the ability of 'Snap-n-Send' to accurately assess the diet of elite adolescent athletes, signalling the exciting promise of this comprehensive and theoretical behavioural approach within valid dietary assessment.

Micronutrient Intakes in 553 Dutch Elite and Sub-Elite Athletes: Prevalence of Low and High Intakes in Users and Non-Users of Nutritional Supplements

This study investigated whether athletes meet micronutrient recommendations and whether the adequacy of their intake is related to the use of dietary supplements, sport nutrition products or a combination. Micronutrient intakes of 553 Dutch (sub-) elite athletes were assessed using web-based 24-h dietary recalls with accompanying nutritional supplement questionnaires. In the majority of both users and non-users of dietary supplements, vitamin D intake was below the estimated average requirement (AR) if supplements were not included in the analysis. Including dietary supplements improved vitamin D intake, but still a part of the athletes, both men and women, reported an intake below the AR. Non-users of dietary supplements were particularly at risk for low intakes of vitamins B1, B2, B3 and vitamins A, C and selenium. Mean iron intake was reported below the AR in a substantial group of women, both users and non-users. The use of sport nutrition products contributed only slightly to micronutrient intake. A small prevalence of athletes using dietary supplements showed intakes of some micronutrients above the Upper Level. In conclusion, both users and non-users of nutritional supplements reported inadequate intake of micronutrients. For most micronutrients, use of nutritional supplements does not completely compensate for intakes below AR. Athletes should consider making better food choices and the daily use of a low-dosed multivitamin supplement.

Macronutrient Intakes in 553 Dutch Elite and Sub-Elite Endurance, Team, and Strength Athletes: Does Intake Differ between Sport Disciplines?

Web-based 24-h dietary recalls and questionnaires were obtained from 553 Dutch well-trained athletes. The total energy and macronutrient intake was compared between discipline-categories (endurance, team, and strength) within gender, and dietary inadequacy, i.e., too low or high intakes, according to selected recommendations and guidelines, was evaluated by applying a probability approach. On average, 2.83 days per person were reported with a mean energy intake of 2566-2985 kcal and 1997-2457 kcal per day, for men and women, respectively. Between disciplines, small differences in the mean intake of energy and macronutrients were seen for both men and women. Overall, 80% of the athletes met the suggested lower-limit sport nutrition recommendation of 1.2 g·kg^-1 of protein per day. The carbohydrate intake of 50%-80% of athletes was between 3 and 5 g·kg^-1 bodyweight, irrespective of the category of their discipline. This can be considered as low to moderate, in view of their daily total exercise load (athletes reported on average ~100 minutes per day). In conclusion, only small differences in the mean energy and macronutrient intake between elite endurance, strength, and team sport athletes, were found. The majority of the athletes were able to meet the generally accepted protein recommendation for athletes, of 1.2 g·kg^-1. However, for most athletes, the carbohydrate intake was lower than generally recommended in the existing consensus guidelines on sport nutrition. This suggests that athletes could either optimize their carbohydrate intake, or that average carbohydrate requirements merit a re-evaluation.

A review of the design and validation of web- and computer-based 24-h dietary recall tools

Technology-based dietary assessment offers solutions to many of the limitations of traditional dietary assessment methodologies including cost, participation rates and the accuracy of data collected. The 24-h dietary recall (24HDR) method is currently the most utilised method for the collection of dietary intake data at a national level. Recently there have been many developments using web-based platforms to collect food intake data using the principles of the 24HDR method. This review identifies web- and computer-based 24HDR tools that have been developed for both children and adult population groups, and examines common design features and the methods used to investigate the performance and validity of these tools. Overall, there is generally good to strong agreement between web-based 24HDR and respective reference measures for intakes of macro- and micronutrients.