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

Abstract

Information on dietary composition is vitally important for elite athletes to optimise their performance and recovery, which requires valid tools. The aim of the present study was to investigate the validity of assessing protein intake using three web-based 24-h recalls and questionnaires, by comparing these with three urinary N excretions on the same day. A total of forty-seven Dutch elite top athletes, both disabled and non-disabled, aged between 18 and 35 years, with a BMI of 17·5-31 kg/m 2 , exercising >12 h/week were recruited. Estimated mean dietary protein intake was 109·6 (SD 33·0) g/d by recalls and questionnaires v. 141·3 (SD 38·2) g/d based on N excretions in urine; the difference was 25·5 (SD 21·3) % between the methods (P < 0·05). We found a reasonably good association between methods for protein intake of 0·65 (95 % CI 0·45, 0·79). On an individual level, under-reporting was larger with higher protein intakes than with lower intakes. No significant differences were found in reporting absolute differences between subcategories (sex, under-reporting, BMI, collection of recalls within a certain amount of time and using protein supplements or not). In conclusion, combined, multiple, 24-h recalls and questionnaires underestimated protein intake in these young elite athletes more than that reported for non-athlete populations. The method proved to be suitable for ranking athletes according to their protein intake as needed in epidemiological studies. On an individual level, the magnitude of underestimation was about equal for all athletes except for those with very high protein intakes.

Habitual Dietary Nitrate Intake in Highly Trained Athletes

“…Though the dietary habits of athletes are notoriously constant, we cannot exclude the possibility that a slight change in dietary habits and nitrate intake may have occurred throughout the 3-year collection period (e.g., due to changing food trends). Furthermore, there are several limitations of dietary assessments in athletes (Magkos & Yannakoulia, 2003) such as self-reported estimation of portion sizes, frequency of snacking, and underreporting, which have previously been described for a subselection of the current dataset (Wardenaar et al, 2015). However, the inclusion of 2-4 dietary registration days per person and verification of food intake by certified dietitians, strongly improves the validity for food consumption surveys to evaluate dietary intake (Brussaard et al, 2002).…”

“…Data were collected as part of the Dutch Sport Nutrition and Supplement Study (DSSS) that was performed between February 2012 and June 2015 (Wardenaar et al, 2015). In short, participants were asked to complete 2-4 unannounced web-based (Compl-eat) 24-hr dietary recalls and dietary supplement questionnaires during the conditioning phase of their training program.…”

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

“…Bland & Altman (51) analysis was only used by six investigators, four of which investigated the agreement and bias in nutrient intakes recorded by test and reference methods (5,27,52,53) . Moore et al (21) investigated agreements between methods in the recording of food and drink items and Carvalho et al (22) investigated estimated v. observed amounts consumed using Bland-Altman analysis.…”

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

“…The validity of 'Snap-n-Send' exceeds those of a range of approaches deployed within nonathletic and elite athlete populations (Wardenaar et al, 2015;Wood, 2014). These approaches include leading photography-based m-DIA (Gemming, Utter, & Ni Mhurchu, 2015;Henriksson et al, 2015), combined traditional and m-DIA assessments (Gemming et al, 2015), augmented reality m-DIA (Pouladzadeh, Shirmohammadi, & Yassine, 2016), wearable cameras (Gemming et al, 2015;Pettitt et al, 2016) and other innovative e-DIA (Rollo, Ash, Lyons-Wall, & Russell, 2015).…”