In a recent publication by Liam Anderson from Liverpool John Moores University and colleagues unique insights in English Premier League football (soccer for those across the pond) were obtained. The results of the study were also discussed in December 2016 at the ISENC Sports Nutrition conference in Newcastle (UK) by Dr James Morton. Six professional soccer players of Liverpool Football club were followed during training and matches in order to get a better insight in their energy expenditure and energy intake.
The researchers used the most accurate technique possible for free-living conditions to measure energy expenditure, an advanced technique called the doubly labelled water method. This technique uses different excretion rates of oxygen and hydrogen to calculate energy expenditure and is generally regarded as the gold standard. The investigators also obtained detailed nutrition intake information from the players on different days: match days, recovery days and training days.
Energy expenditure was on average 3566 kcal/day (but was of course higher on the match days and lower on recovery days). Energy intake on match days averaged 3789 kcal and on training days 2956 kcal. All these figures are similar to what has been reported in the literature previously.
Of course it is particularly interesting to see if the players meet the recommendations especially for match play. For example, it is recommended to have different carbohydrate intakes on match days or hard training days versus easier days or rest days, but carbohydrate intake should be centred around the days with a higher load. On rest days a carbohydrate intake of 5 g/kg may be sufficient whereas on match days, in preparation for match day and in recovery from matches intake would have to be closer to 7 g/kg to meet the carbohydrate requirements of match play and optimise glycogen resynthesis
The players reported an intake of 4.2 g/kg/day on training days and an average intake of 6.4 g/kg on match days. It is recommended to make sure that glycogen stores are fully replenished before a match by eating a diet relatively high in carbohydrate and that the day or days after carbohydrate intake is slightly elevated to make sure glycogen can be restored to high levels before the match. This did not seem to happen, so the authors concluded that carbohydrate intake around match days can be further optimised.
Players had no problem achieving recommendations for daily protein intake but what may be more important is the distribution of protein intake during the day and this is something that should be looked at as well.