Carbohydrate availability and caffeine ingestion have been shown to elicit improvements in performance independently of one another. The purpose of the study was to examine the effect of a carbohydrate + caffeine beverage on performance and perceived effort in soccer players. Forty-three collegiate women’s soccer athletes were recruited to participate during a single day of simulated match play, in which each team played once. Athletes consumed either a carbohydrate + caffeine (Experimental) beverage or a control (Control) beverage (flavored water) during half-time in a double-blind, placebo-controlled, randomized control trial design. Prior to and after each game, Ratings of Perceived Exertion (RPE) and blood glucose levels were assessed. Heart rate, training impulse (TRIMP), total distance covered, high-speed distance, and velocity were recorded. Blood glucose levels after the match simulation were positively associated with total distance (r = 0.434; p = 0.01), distance per minute (r = 0.439; p < 0.01), average velocity (r = 0.438; p = 0.01), and TRIMP (r = 0.404; p = 0.018) during the second half. There was a significant main effect for half regarding blood glucose (p < 0.001), total distance (p < 0.001), high-speed distance (p < 0.001), and TRIMP (p = 0.046). There was a significant half × condition effect for blood glucose (p = 0.05). Pairwise comparisons indicated the Experimental beverage condition resulted in a +27 mg/dL (95% CI: −3.6, 58.8) difference compared to the Control beverage following the 2nd Half. In the current study, consumption of the carbohydrate + caffeine beverage during half-time resulted in higher blood glucose levels post-game compared to placebo; however, the experimental beverage did not influence the total distance covered, average velocities, average heart rate, or TRIMP values during the second half of simulated match play.
Nutrition Knowledge and Perceived Dietary Requirements of Adolescent Student-Athletes: A Pilot Study
Background/Objectives: Adherence to sports-specific nutritional guidelines can help optimize athlete performance and health. However, adolescent athletes may not have adequate nutrition knowledge and understanding of specific nutritional requirements. The objective of the current study was to examine the nutrition knowledge and perceived dietary requirements of adolescent athletes. Methods: Male (n = 29, age: 15.7 ± 1.3 yrs.; height: 178.9 ± 8.3 cm; body mass: 74.7 ± 17.2 kg; body fat %: 13.9 ± 7.9%) and female (n = 15, age: 16.5 ± 1.4 yrs.; height: 169.9 ± 6.5 cm; body mass: 63.3 ± 4.5 kg; body fat %: 23.7 ± 3.8%) secondary school student-athletes completed body composition testing (hydrostatic weighing) and electronic surveys (Abridged Sports Nutrition Knowledge Questionnaire (ASNKQ); self-perception of dietary energy and macronutrient requirements). Results: Athletes demonstrated poor sports nutrition knowledge, with no differences observed between sexes for the number of questions answered correctly (males: 45.1 ± 9.8% vs. females: 43.1 ± 12.7%; p = 0.57). No relationships were observed between ASNKQ scores and body composition parameters or between ASNKQ scores and self-reported perception of dietary energy and macronutrient requirements (p > 0.05). Athletes self-reported a lower perceived energy (−560 ± 1272 kcal/d; p = 0.014) and carbohydrate intake (−73 ± 376 g/d; p = 0.014) requirement compared to calculated nutritional recommendations. Athletes self-reported a higher perceived protein intake (263 ± 586 g/d; p = 0.026) requirement compared to calculated nutritional requirements. Conclusions: The current sample of adolescent athletes from the secondary school level appears to have a poor level of sports nutrition knowledge and understanding of energy and macronutrient requirements.
Body Composition, Energy Availability, Risk of Eating Disorder, and Sport Nutrition Knowledge in Young Athletes
Young athletes may be at risk for low energy availability (LEA) or dietary habits that are indicative of eating disorders. Thus, the purpose of the current study was to investigate the prevalence of LEA among high school athletes and examine those at risk for eating disorders. A secondary aim was to examine relationships between sport nutrition knowledge, body composition, and LEA. Methods: 94 male (n = 42) and female (n = 52) mean ± SD age: 18.09 ± 2.44 y; height: 172.6 ± 9.8 cm; body mass: 68.7 ± 14.5 kg; BMI: 22.91 ± 3.3 kg·m−2) athletes completed a body composition assessment and electronic versions of the abridged sports nutrition knowledge questionnaire (ASNK-Q), brief eating disorder in athletes questionnaire (BEDA-Q), and the low energy availability for females questionnaire (LEAF-Q; females only). Results: 52.1% of female athletes were classified as being at risk for LEA. Moderate inverse relationships existed for computed LEAF-Q scores and BMI (r = −0.394; p < 0.01). A total of 42.9% of males (n = 18) and 68.6% of females (n = 35) were at risk for eating disorders, with females being at greater risk (p < 0.01). Body fat percentage was a predictor (β = −0.095; p = −0.01) for eating disorder risk status. For every 1 unit increase in body fat percentage, athletes were 0.909 (95% CI: 0.845–0.977) times less likely to be classified as at risk for an eating disorder. Male (46.5 ± 13.9) and female (46.9 ± 11.4) athletes scored poorly on the ASNK-Q, with no differences between sex (p = 0.895). Conclusions: Female athletes were at a greater risk for eating disorders. No relationships existed between sport nutrition knowledge and %BF. Female athletes with a higher %BF had a lower risk for an eating disorder and risk for LEA.
Body Composition And Oral Contraceptive Use In Young Female Athletes