Reading Passage: Prevention, Implementing a Well-Balanced Diet for the Growing Athlete

Module 12: Prevention: Implementing a Well-Balanced Diet for the Growing Athlete

Adolescence is a critical time for growth and development. It is also an important time to establish a lifelong relationship with food and the connection between diet, exercise, and body image. Research shows that adolescent athletes who maintain good nutrition knowledge have to higher daily energy availability and carbohydrate intake. Understand the below information and share it with your athlete in an appropriate manner that promotes their health and wellness.
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Higher Caloric Need:

Adolescent athletes have a higher resting metabolic rate in addition to their high energy expenditures. Thus, they require more “leftover energy” aka energy availability. This means that athletes should either limit their energy expenditure or increase their food intake (the latter is often easier in structured training plans). While there are general estimates for how much energy adolescent athletes need (around 3640 kcal/day for males and 3100 kcal/day for females), individual energy requirements can vary due to factors such as changes in training or workloads, participation in multiple sports, and sedentary behaviors. Determining individual energy needs is also complicated by variations in metabolism and hormones between individuals, as well as challenges in accurately measuring energy intake and expenditure
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Protein Requirements:

Adolescents have higher protein requirements than adults because there is a substantial increase in lean body mass during puberty. Thus, protein is essential for healthy growth and development. Protein is also essential to maximize the performance and recovery goals of athletics. Adequate energy intake is crucial to prevent protein (i.e. muscles) from being used as an energy source instead.

• 0.11 grams per kilogram of body weight per hour during post-exercise recovery
• OR the equivalent of approximately 1.5 grams per kilogram of body weight per day

Carbohydrate Requirements:

The way carbohydrates are used and replenished during exercise depends on the length and intensity of the workout. Research has shown that there is no significant difference in how adolescents and adults utilize carbohydrates. However, adolescents may be less capable of adapting to changes in carbohydrate availability compared to adults. In other words, adolescents may be more vulnerable to health consequences with low carbohydrate intake and stores.Thus, carbohydrate intake should depend on the amount and intensity of the exertion rather than the age of the individual. Adolescents often participate in higher quantity and intensity of exercise than adults, so therefore they should consume more carbohydrates than their adult counterparts. Short exercise duration may benefit from a carbohydrate mouth rinse or small amounts of carbohydrate intake. Endurance events over 90 minutes may benefit from carbohydrate loading strategies.
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Fat Requirements:

Sufficient consumption of dietary fat is important for adolescent athletes to meet their nutritional requirements for essential fatty acids and fat-soluble vitamins, and to provide energy for growth and maturation. Research shows that younger athletes may have slightly higher max rates of fat oxidation relative to lean mass.

Recommendations for total and type of fat intake for adolescent athletes aligns with the general health guidelines for adults with 20-35% of total energy coming from fat and no more than 10% of total energy intake from saturated and trans fatty acids. The focus should be on healthy fats, such as those found in nuts, avocado, fatty fish, and olive oil.
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Micronutrients:

Iron
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Studies on adolescent athletes, especially those in endurance sports, frequently show depleted iron stores, even without clinical symptoms. Even mild decreases in tissue iron have the potential to adversely affect endurance capacity and aerobic adaptation to training. Vegetarian athletes may have increased iron requirements due to the low iron bioavailability of non-heme iron sources. While most studies show no significant differences in dietary iron intake or hemoglobin concentrations between vegetarians and non-vegetarians, it is advisable for adolescent vegetarian athletes to monitor their iron status regularly. It is important to detect and treat iron depletion early in adolescent athletes because the rapid growth during adolescence increases  iron requirements, and progression from low iron stores to iron deficiency is rapid.

Calcium

‍Need for calcium is highest during pubertal growth spurts with adolescents estimated to require around 300 mg/day for skeletal production. Recommendations for calcium intake in the US is 1300 mg/day for males and females aged 14-18 years. High-intensity weight-bearing exercise and resistance exercise have been shown to increase bone mineral content in exercising adolescents. Although the increase is small, this effect can maximize peak hip strength and prevent osteoporosis later in life.

Vitamin D

Vitamin D (25 hydroxyvitamin D) is most commonly associated with bone health, but it also contributes to immune and muscular systems. Insufficient vitamin D can cause muscle pain, weakness, inflammation, and impaired skeletal muscle function. This may also increase risk of injury and extend the time it takes to recovery from injury.

Young athletes are at risk of vitamin D deficiency if they have reduced sun exposure, spend extended periods training indoors, have dark skin, use sunscreen, or wear protective clothing. It is important for health professionals to monitor vitamin D levels for those at-risk. Daily recommended intake in the US is 15 μg/day.
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Healthy Eating Behaviors:

Participating in sports can benefit mental health and promote a positive body image, but sports that emphasize leanness for optimal performance can lead to disordered eating behaviors. Therefore, it is important to educate adolescent athletes about developing a healthy relationship with food, and to discourage restrictive diets and unhealthy training strategies. Here are some key areas to focus on.

• Discourage restrictive diets and unhealthy training strategies (i.e. overtraining)
• Discourage weight-related comments
• Avoid unnecessary nutrition/food discussions
• Eliminate body composition/weight assessments
• Raise awareness of the negative effects of chronic LEA
• Monitor the athlete's growth and development
• Address toxic training environments that involve body shaming or manipulating an athlete’s physique regardless of performance
• Young athletes should avoid intentional body weight changes as it may delay pubertal development, growth, and bone growth, and increase the risk of developing eating disorders.
• Injured athletes should  maintain optimal food consumption to support their rehabilitation.

Fluid Intake:

Adolescent individuals have a similar ability as adults to exercise in hot conditions; however, they rely more on peripheral blood redistribution, rather than sweating, to maintain their heat equilibrium until puberty is completed.

Causes of dehydration include inadequate hydration, excessive physical exertion, insufficient cooling, and inappropriate clothing. Developing athletes may not recognize signs of heat stress, forget to drink water, and continue to exercise.

Fluid intake guidelines for young athletes align with those for adults, with fluid intakes of 13 mL/kg per hour of exercise. Fluid intake should also align with the intensity and duration of an athlete’s exertion.
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Supplements:

Although there is minimal scientific evidence, many young athletes use supplements to enhance their performance. The most commonly used supplements by adolescent athletes include vitamin/mineral supplements, sports/protein powders, vitamin waters, creatine, and caffeine. These supplements are often used due to pressure to achieve heightened performance, pursuit of physical ideals, peer pressure, social pressure, and marketing pressure.

It is typically not recommended for young athletes to use dietary supplements, except when prescribed by a qualified health professional. The focus should be on proper training, nutrition, and rest practices.