Isolated & combined wearable technology underestimate the total energy expenditure of professional young rugby league players ; a doubly labelled water validation study

Accurately determining total energy expenditure enables the precise manipulation of energy balance within professional collision-based sports. Therefore, this study investigated the ability of isolated or combined wearable technology to determine the total energy expenditure of professional young rugby league players across a typical pre-season and in-season period. Total energy expenditure was measured via doubly labelled water, the criterion method, across a fourteen-day pre-season (n=6) and seven-day in-season (n=7) period. Practical measures of total energy expenditure included SenseWear Pro3 Armbands in isolation and combined with metabolic power derived from microtechnology units. SenseWear Pro3 Armbands significantly under-reported pre-season (5.00 (2.52) MJ.day-1; p = 0.002) and in-season (2.86 (1.15) MJ.day-1; p < 0.001) total energy expenditure, demonstrating a large and extremely large standardised mean bias, and a very large and large typical error, respectively. Combining metabolic power with SenseWear Pro3 Armbands almost certainly improved pre-season (0.95 (0.15) MJ.day-1; ES = 0.32 ±0.04; p < 0.001) and in-season (1.01 (0.15) MJ.day-1; ES = 0.88 ±1.05; p < 0.001) assessment. However, SenseWear Pro3 Armbands combined with metabolic power continued to significantly under-report pre-season (4.04 (2.38) MJ.day-1; p = 0.004) and in-season (2.18 (0.96) MJ.day-1; p = 0.002) expenditure, demonstrating a large and very large standardised mean bias, and a very large and large typical error, respectively. These findings demonstrate the limitations of utilising isolated or combined wearable technology to accurately determine the total energy expenditure of professional collision-based sport athletes across different stages of the season

Collision activity during training increases total energy expenditure measured via doubly labelled water

Purpose: Collision sports are characterised by frequent high intensity collisions that induce substantial muscle damage, potentially increasing the energetic cost of recovery. Therefore, this study investigated the energetic cost of collision-based activity for the first time across any sport. Methods: Using a randomised crossover design, six professional young male rugby league players completed two different five-day pre-season training microcycles. Players completed either a collision (COLL; 20 competitive one-on-one collisions) or non-collision (nCOLL; matched for kinematic demands, excluding collisions) training session on the first day of each microcycle, exactly seven days apart. All remaining training sessions were matched and did not involve any collision-based activity. Total energy expenditure was measured using doubly labelled water, the literature gold standard. Results: Collisions resulted in a very likely higher (4.96 ± 0.97 MJ; ES = 0.30 ±0.07; p=0.0021) total energy expenditure across the five-day COLL training microcycle (95.07 ± 16.66 MJ) compared with the nCOLL training microcycle (90.34 ± 16.97 MJ). The COLL training session also resulted in a very likely higher (200 ± 102 AU; ES = 1.43 ±0.74; p=0.007) session rating of perceived exertion and a very likely greater (-14.6 ± 3.3%; ES = -1.60 ±0.51; p=0.002) decrease in wellbeing 24h later. Conclusions: A single collision training session considerably increased total energy expenditure. This may explain the large energy expenditures of collision sport athletes, which appear to exceed kinematic training and match demands. These findings suggest fuelling professional collision-sport athletes appropriately for the "muscle damage caused” alongside the kinematic “work required”. Key words: Nutrition, Recovery, Contact, Rugb

Wearable technology underestimates the total energy expenditure of professional athletes

Accurately determining total energy expenditure (TEE) enables the precise manipulation of energy balance within professional collision-based sports. Therefore, this study investigated the ability of isolated or combined wearable technology to determine the TEE of professional young rugby league players across a typical preseason and in-season period. Total energy expenditure was measured via doubly labelled water, the criterion method, across a fourteen-day preseason (n = 6) and 7-day in-season (n = 7) period. Practical measures of TEE included SenseWear Pro3 Armbands in isolation and combined with metabolic power derived from microtechnology units. SenseWear Pro3 Armbands significantly under-reported preseason (5.00 [2.52] MJ·d−1; p = 0.002) and in-season (2.86 [1.15] MJ·d−1; p &lt; 0.001) TEE, demonstrating a large and extremely large standardized mean bias, and a very large and large typical error, respectively. Combining metabolic power with SenseWear Pro3 Armbands almost certainly improved preseason (0.95 [0.15] MJ·d−1; Effect size = 0.32 ± 0.04; p &lt; 0.001) and in-season (1.01 [0.15] MJ·d−1; ES = 0.88 ± 1.05; p &lt; 0.001) assessment. However, SenseWear Pro3 Armbands combined with metabolic power continued to significantly under-report preseason (4.04 [2.38] MJ·d−1; p = 0.004) and in-season (2.18 [0.96] MJ·d−1; p = 0.002) expenditure, demonstrating a large and very large standardized mean bias, and a very large and large typical error, respectively. These findings demonstrate the limitations of utilizing isolated or combined wearable technology to accurately determine the TEE of professional collision-based sport athletes across different stages of the season

Can a contemporary dietary assessment tool or wearable technology accurately assess the energy intake of professional young rugby league players? A doubly labelled water validation study

Accurate quantification of energy intake is imperative in athletes; however traditional dietary assessment tools are frequently inaccurate. Therefore, this study investigated the validity of a contemporary dietary assessment tool or wearable technology to determine the total energy intake (TEI) of professional young athletes. The TEI of eight professional young male rugby league players was determined by three methods; Snap-N-Send, SenseWear Armbands (SWA) combined with metabolic power and doubly labelled water (DLW; intake-balance method; criterion) across a combined ten-day pre-season and seven-day in-season period. Changes in fasted body mass were recorded, alongside changes in body composition via isotopic dilution and a validated energy density equation. Energy intake was calculated via the intake-balance method. Snap-N-Send non significantly over-reported pre-season and in-season energy intake by 0.21 (2.37) MJ.day−1 (p = 0.833) and 0.51 (1.73) MJ.day−1 (p = 0.464), respectively. This represented a trivial and small standardised mean bias, and very large and large typical error. SenseWear Armbands and metabolic power significantly under-reported pre-season and in-season TEI by 3.51 (2.42) MJ.day−1 (p = 0.017) and 2.18 (1.85) MJ.day−1 (p = 0.021), respectively. This represents a large and moderate standardised mean bias, and very large and very large typical error. There was a most likely larger daily error reported by SWA and metabolic power than Snap-N-Send across pre-season (3.30 (2.45) MJ.day−1; ES = 1.26 ± 0.68; p = 0.014) and in-season periods (1.67 (2.00) MJ.day−1; ES = 1.27 ± 0.70; p = 0.012). This study demonstrates the enhanced validity of Snap-N-Send for assessing athlete TEI over combined wearable technology, although caution is required when determining the individual TEIs of athletes via Snap-N-Send