Dietary Intake and Daily Distribution of Carbohydrate, Protein and Fat in Youth Tennis Players over a 7-Day Training and Competition Period

Abstract

During a 7-day training and/or competition period, macronutrient intake and distribution was assessed using food diaries, supported by remote food photography and 24-hr multiple pass recalls of youth tennis players categorised by under 12s, under 14s and under 16+ age groups (n = 27). Total energy did not differ between age groups nor type of day (training [TD], competition day [CD]), irrespective of a significant increase in body mass reported in the older players (U16+; p < 0.05). Average intakes were consistently below 2250 kcal·day-1 (range 1965 ± 317–2232 ± 612 kcal·day-1). Carbohydrate consumption was below guidelines for all groups (≤6g·kg-1). Conversely, protein intake met or exceeded guidelines throughout, with intakes ≥2 g·kg-1 for both the U12 and U14 age groups on both days. Protein intake was ~17% higher on TDs than CDs (p < 0.05), with protein intake at lunch significantly higher on TDs than CDs (p < 0.05). No further differences were observed between breakfast, lunch or dinner between group or day. Inconsistent snacking was reported, with players consuming snacks on less than half of the days reported (46 ± 12% of TDs and 43 ± 30% of CDs). In conclusion, youth tennis players present sub-optimal nutrition practices, appearing to under fuel and under consume carbohydrate for performance, adaptation, recovery and health.

Biomechanical Analysis of Touch Ball Movements in Tennis Forehand Strokes

“…Whether open stance and closed stance will affect the hitting speed and joint force, Fillmore and Hall think that open stance will cause a greater load on the athlete's body; however, some studies have also found that closed stance forehands have greater peak shoulder internal rotation torque and greater peak wrist flexion torque; this is in contrast to the idea that open stance shots place a greater load on the upper body [ 8 ]. Fleming et al study the characteristics of trunk muscle activation during open and closed forehand strokes in tennis; the results of the study do not support the hypothesis that open poses produce greater trunk muscle activation than closed poses; the external oblique is important in axial rotation, and female tennis players may require greater external oblique activation due to fewer external oblique muscle fibers [ 9 ]. While Bankosz and Winiarski suggested that the upper extremity dynamics of the open and closed forehand are very similar, except for the peak torque in shoulder internal rotation and wrist flexion, all subjects developed shoulder internal rotation torque during the forward swing, and the closed shoulder internal rotation torque was significantly greater than the open one, and the wrist flexion torque was also significantly greater [ 10 ].…”

Nutrition and the elite and highly trained junior and young adult tennis player: A scoping review

“…Yli-Piipari 23 established five female NCAA Division 1 players to consume 2011 ± 207 kcal . day −1 , and Fleming et al 25 reported intakes consistently below 2250 kcal . day −1 irrespective of age group (ranging from 12–20 year olds).…”

“…40 Research to date largely fails to consider the distribution and timing of dietary intake, limited to two studies. 23,25 Initial insights suggest a lack of nutritional planning, with no clear differences in nutritional intake (total caloric intake and macronutrient distribution) established between type of day (rest, training, competition) nor meal (breakfast, lunch, dinner, snacks). This raises concerns regarding nutritional knowledge and the amount of time players spend planning and considering their dietary intake.…”

“…Protein intakes >1.4 g . kg.bm −1 were reported in four studies [23][24][25]27 ranging from 1.43 ± 0.43 g . kg.bm −1 27 -2.4 ± 0.2 g .…”

“…Potential limitations of this scoping review are the heterogeneity and breadth of studies included. Specifically, methods used to quantify dietary intake largely focussed on self-reported food diaries, inherently associated with under-reporting, 45 with only one study utilising multiple methods (food diaries, dietary recall and food photography), 25 deemed a more robust method of accurately assessing dietary intake. 46 This too was evident in the quantification of EE.…”