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

Abstract

PurposeCollision 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.MethodsUsing a randomised crossover design, six professional young male rugby league players completed two different 5-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 7 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.ResultsCollisions resulted in a very likely higher (4.96 ± 0.97 MJ; ES = 0.30 ± 0.07; p = 0.0021) total energy expenditure across the 5-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 24 h later.ConclusionsA 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”.Electronic supplementary materialThe online version of this article (10.1007/s00421-018-3846-7) contains supplementary material, which is available to authorized users.

Daily Changes of Resting Metabolic Rate in Elite Rugby Union Players

“…We therefore speculate that the collisions encountered on a game day could be responsible for the significant changes in RMR reported at GD+1. This may account for the increases in TEE previously observed in youth players when a training session contained collisions similar to that of match play (14).…”

“…It is therefore crucial that accurate and quantitative markers are developed to assess the extent of the IIMD to allow more targeted interventions to be developed. One potential candidate is assessing the energy expenditure of players given that the total energy expenditure (TEE) of young rugby league players was 5% higher when training weeks involved collisions (14).…”

There Is Little Difference in the Peak Movement Demands of Professional and Semi-Professional Rugby League Competition

“…Whilst the locomotor demands are similar, the concomitant contact demands may be greater for professional players (Gabbett, 2013; Johnston et al, 2014a; Hausler et al, 2016). Previous research has highlighted the significant energetic cost of physical contact in rugby league players (Norris et al, 2016; Costello et al, 2018), causing reductions in running intensity (Johnston et al, 2014c, 2015, 2016), and increases in markers of fatigue (Johnston et al, 2014b). A recent study has looked at the peak running and contact demands of professional competition (Weaving et al, 2018), but no studies have assessed the peak contact and running demands of semi-professional competition.…”

Returning to Play after Prolonged Training Restrictions in Professional Collision Sports

“…One of the main challenges for bespoke nutritional intervention during this period will be the accurate assessment of daily energy expenditure with a ‘ one-size fits all ’ approach being particularly problematic. Rugby players have large inter-individual differences in daily energy expenditure when measured via doubly-labelled water, even when the players appear to be undertaking similar training sessions ( Table 1 ) 106 107 108 109 . This highlights the substantial contribution of activities away from the training ground on total daily energy expenditure, and it is therefore essential that nutritionists attempt in some way to quantify the activities of the day during this period of training restriction.…”