Food Composition for Youth Cross Country Runners

At Saturday, our goal is to enhance athletic performance by strategically augmenting nutrition. An integral part of this strategy involves comprehensive knowledge of food composition, including digestibility, bioavailability, and the concentration of crucial nutrients. Although food composition may not be the primary factor in athletic performance, it plays a significant role in determining a young runner's nutritional wellbeing and metabolic proficiency.

Proteins: Checking Quality and Digestibility

Evaluating proteins involves focusing on their quality and digestibility. Protein quality primarily depends on the spectrum and proportions of amino acids it encompasses. Among the 20 amino acids, 11 are internally produced (non-essential), while the remaining 9 (essential) must be obtained through dietary intake. Proteins are categorized as either complete or incomplete, based on the presence or absence of all essential amino acids. However, intelligent pairing of multiple incomplete proteins can create a complementary protein that collectively meets the essential amino acid requirement. Foods such as chicken, beef, and fish are complete proteins, while beans and nuts are incomplete proteins but can be partnered to deliver a full amino acid profile.

The digestibility of a protein, which indicates the proportion of ingested protein that the body absorbs and uses, is another critical aspect. The Protein Digestibility Corrected Amino Acid Score (PDCAAS) offers a reliable measure of protein digestibility, evaluated on a scale from 0 to 1.0. Animal-based products typically have high PDCAAS scores, indicating superior digestibility and quality. In contrast, plant-derived proteins usually have reduced digestibility, largely due to the presence of cellulose—an indigestible component of plant cell walls—that impedes complete protein absorption. Given these findings, we recommend that a substantial part of a young runner's protein intake should come from animal sources due to their excellent quality and digestibility.

Carbohydrates: Grasping Digestion Time and Nutrient Density

Assessing the quality of carbohydrates relies on two factors: digestion time and nutrient density. The Glycemic Index (GI), a scale from 0 (lowest) to 100 (highest), serves as the reference. It measures the speed of digestion and absorption of carbohydrates into the bloodstream, with quick-digesting sources causing a swift blood sugar spike and thus higher GI values. Slow-digesting sources result in a more gradual increase and lower GI values.

The GI is relevant to both health and athletic performance. Lower GI carbohydrates, such as whole grains and legumes, often offer additional health benefits such as fiber content, micronutrients, and phytochemicals. Conversely, for young cross country runners, consuming high-GI carbohydrates, such as sugar, during training ensures a rapid glucose supply to the bloodstream while minimizing gastrointestinal discomfort. A useful guideline is that the further from training you are, the lower the GI of your carbohydrate intake should be.

Fats: Understanding the Types

The quality of fat is primarily dictated by its type: monounsaturated, polyunsaturated (including omega-3 and omega-6), saturated, and trans fats. While fats form an integral part of macronutrients, their contribution to athletic performance is relatively modest, mainly serving to maintain health. Runners should prioritize the inclusion of monounsaturated, polyunsaturated, and saturated fats while minimizing or completely avoiding trans fats due to their potential adverse health effects. Foods like avocados, nuts, and olive oil are rich in monounsaturated fats, while fatty fish and flaxseeds are good sources of polyunsaturated fats. Animal products like butter and cheese provide saturated fats.

Conclusion

In conclusion, while food composition might not be the leading driver in athletic performance, it plays a pivotal role. A nuanced understanding of protein quality and digestibility, the consideration of carbohydrate digestion time and nutrient density, and the inclusion of healthy fats are crucial for optimizing nutrition for youth cross country runners. By prioritizing these aspects of food composition, young runners can support their athletic performance, promote healthy growth and development, and lay the foundation for lifelong nutritional habits. Therefore, implementing sound nutrition principles that take into account food composition is essential for youth cross country runners to thrive both on and off the running track.