Significant Changes in Resting Metabolic Rate Over a Competitive Match Week Are Accompanied by an Absence of Nutritional Periodization in Male Professional Soccer Players
in International Journal of Sport Nutrition and Exercise Metabolism 2023 Jennie L. Carter
Resting metabolic rate (RMR) is an important component of total daily energy expenditure; however, it is currently not understood how it varies across a typical competitive match week in professional soccer players. For the first time, we aimed to assess RMR throughout an in-season competitive week in professional soccer players. Additionally, we aimed to assess energy and carbohydrate intake across the same week. Twenty-four professional soccer players from an English Premier League club (age: 18 ± 1.6 years) completed the study. RMR was assessed each morning of a typical competitive match week (match day [MD] −3, −2, −1, +1, +2, and + 3), and dietary intake (including MD) was assessed daily via the remote food photography method and 24-hr recall. Daily training load was quantified using Global Positioning System, daily muscle soreness ratings were recorded, and body composition was assessed via dual-energy X-ray absorptiometry.
There was a significant (p = .0004) increase in mean RMR of ∼261 kcal/day on MD + 1, compared with MD − 1. Additionally, volume of oxygen consumed significantly increased at MD + 1 (p = .0002) versus MD − 1. There were no significant differences in daily energy or carbohydrate intake across the competitive week (p > .05), with inadequate carbohydrate intakes on MD − 1 (∼3.9 g/kg body mass), MD (∼4.2 g/kg body mass), and MD + 1 (∼3.6 g/kg body mass) in relation to current recommendations. We report, for the first time, that RMR is significantly increased following a competitive match in professional soccer players.
In addition, we confirm previous findings to reinforce that players exhibit inadequate nutrition periodization practices, which may impair physical performance and recovery.