Nutrition Periodization for Endurance Athletes

Nutrition plays a fundamental role in the success of endurance athletes, yet it’s a facet of training that often doesn’t receive the same level of attention and planning as other training aspects. Just as physical periodization, which involves varying the volume and intensity of training throughout the year, is crucial for successful race performance, the athlete must also adapt their nutrition strategy to support these changes effectively. This approach is referred to as nutrition periodization.

The primary goal of nutrition periodization is to ensure that athletes receive the necessary nutrients to enhance their health and improve their physical attributes, such as strength, speed, power, and endurance. This strategy not only helps athletes reach their physical potential but also supports their immune system, body weight, and body composition. Moreover, it facilitates high-quality workouts and quicker recovery, thereby contributing to overall athletic performance. Nutrition periodization is an ongoing effort meant to address the athlete’s fluctuating energy needs across different training phases throughout the year, not only when competition is on the horizon. This applies whether the athlete is at the beginning, middle, or end of a training cycle.

Each training cycle follows a distinct pattern, including the preparatory (base), pre-competition (build or intensity), competition (race), and transition (off-season) phases. These cycles may span weeks or months and align with various physical objectives in preparation for competition. While the sports themselves may blend from one season to the next, the basic structure of these cycles remains relatively consistent.

Scientific research provides recommended daily macronutrient ranges for endurance athletes. These ranges encompass carbohydrates (3 to 19 grams per kilogram of body weight), protein (1.2 to 2.0 grams per kilogram of body weight), and fat (0.8 to 3.0 grams per kilogram of body weight). It’s important to note that these ranges vary widely due to the diversity of athletes studied, from those competing in very short-duration events to ultra-endurance athletes. These ranges serve as a foundational guide for individuals who need to create a nutrition plan in conjunction with their specific training program. They are applicable to endurance athletes across different training cycles.

The Myth of the Ideal Diet: Athletes often fall into the misconception that there exists a one-size-fits-all ideal diet. In reality, there is no single perfect diet for every athlete. Athletes may have different food preferences and dietary needs. What’s critical is ensuring that they consume adequate levels of macronutrients (carbohydrates, proteins, fats, and water) and micronutrients (vitamins and minerals) through a balanced diet consisting of various foods. Different athletes might have entirely distinct diets, but if their nutrient requirements are met, they are both on the path to maintaining an ideal diet.

For coaches and athletes to effectively employ the concept of nutrition periodization, they must first understand the athlete’s physical goals. These objectives will guide the selection of foods, their quantities, and the timing of consumption. Nutrition periodization seeks to align an athlete’s nutritional needs with their goals, whether it’s optimizing performance, training for overall health and fitness, or aiming to reduce body fat. Understanding these goals is vital to crafting a suitable nutrition periodization plan.

Hydration and the Female Athlete Triad

Hydration: Staying properly hydrated is essential for an athlete’s performance. Traditionally, there were general recommendations for daily water intake, but these have evolved into a more individualized approach. Several factors influence an athlete’s hydration needs, including their dietary intake, exercise frequency, intensity, duration, sweat rate, and environmental conditions. While laboratory methods like refractometry offer precise assessments of hydration, athletes can determine their hydration status using practical indicators.

Monitoring urine color is a straightforward method, with healthy urine appearing pale yellow to clear, unlike apple juice. However, for athletes taking high-dose vitamin supplements, urine color may not be a reliable indicator. Additionally, urinating at regular intervals, approximately every two hours, serves as another reliable marker of hydration status. To further aid athletes in assessing their hydration, urine color charts are valuable tools.

Common Hydration Questions:

1. Do sports drinks benefit endurance athletes?
   • Yes, the taste of sports drinks promotes adequate fluid intake, and they provide carbohydrates and electrolytes that support metabolic function during exercise.
2. What are the training and performance consequences of frequent alcohol consumption by endurance athletes?
   • Frequent excessive alcohol consumption results in empty calories, dehydration, disrupted sleep patterns, and an increased likelihood of engaging in risky behaviors.
3. Why not drink water until one can’t take another sip if the “thirst response” isn’t a reliable gauge?
   • While inadequate fluid intake is a common issue, overconsumption is also possible. Excessive fluid intake can lead to hyponatremia, or water intoxication, due to either excessive fluid intake or inadequate sodium replacement. Drinking faster than the body can absorb fluid can lead to gastrointestinal issues.

It’s essential to understand that water is not the sole means of meeting daily fluid requirements. Athletes who prefer not to consume plain water can stay hydrated by incorporating foods with high water content, such as fruits and vegetables. Maintaining fluid balance is critical for optimal performance. Electrolyte balance is another aspect of hydration, with sodium, chloride, potassium, and calcium being crucial electrolytes. These substances facilitate various functions in the body and are lost through sweat during exercise. Sports drinks often contain these electrolytes to help replenish losses during physical activity.

The Female Athlete Triad: The Female Athlete Triad encompasses three interconnected conditions: energy deficit (disordered eating), menstrual disturbances (amenorrhea), and bone loss (osteoporosis). This syndrome is most common among female athletes in sports emphasizing a lean physique or those involving weight checks. The three conditions in the triad influence each other significantly. Energy deficiency is central to its development. Chronic energy deficiency can result from not consuming enough calories to meet energy expenditure or burning more calories through training without adequate food intake. Disordered eating behavior is typically associated with energy deficiency, often driven by the desire to achieve a lower body weight.

Common signs and symptoms of the triad include sleep disturbances, constant fatigue, irregular or absent menstrual cycles, stress fractures, a preoccupation with thinness, food restriction, and cold extremities. Education efforts to address the Female Athlete Triad primarily focus on nutrition and disordered eating. Athletes must understand that proper nutrition is as critical as training, playing a crucial role in performance and recovery. Encouraging a focus on health and a positive body image and forming a support team of professionals, including sport dietitians, physicians, counselors, and certified athletic trainers, are effective strategies to help athletes showing signs of the triad.

Year-Round Nutrition Program for Endurance Athletes

Implementing a year-round nutrition program alongside an athlete’s training regimen can yield numerous benefits, including improved health, enhanced performance, and better control of weight and body composition. This nutrition program should adapt in sync with training phases, ensuring that an athlete’s dietary intake aligns with their physical demands.

Common Errors in Nutrition Programs: Two common nutrition-related errors endurance athletes make are inadequate hydration during and after training and inconsistent nutrient intake on a day-to-day basis. Proper hydration is vital for performance and recovery, and failing to hydrate adequately can compromise training effectiveness and recovery. On the other hand, not consistently maintaining appropriate nutrient intake can have adverse effects on both training and recovery. Nutrition periodization aims to harmonize nutrient intake with training loads, reducing the likelihood of these errors.

Nutrition for the Preparatory Cycle: During the preparatory training cycle, athletes may prioritize weight loss and body composition improvement. Daily carbohydrate intake should align with body weight and activity level:

• For moderate-duration, low-intensity training (1 to 3 hours per day), the recommended daily intake is 4 to 7 grams per kilogram of body weight.
• For moderate to heavy training (3 to 4 hours per day), the recommended daily intake is 7 to 10 grams per kilogram of body weight.
• For extreme training (4 to 6 hours or more per day), the recommended daily intake is 10 or more grams per kilogram of body weight. However, most athletes won’t reach this category in this cycle.

To meet these carbohydrate needs, athletes should primarily consume fruits and vegetables, which offer essential vitamins, minerals, antioxidants, and fiber. A goal of 6 to 12 servings of fruits and vegetables per day is achievable by distributing these servings throughout meals and snacks.

Protein intake, based on body weight and goals for body weight, can range from 1.2 to 1.7 grams per kilogram of body weight. Athletes should opt for lean sources of protein, like low-fat dairy products, and lean cuts of meat, poultry, or fish without skin or visible fat.

Daily fat intake should remain relatively low, at 0.8 to 1.0 grams per kilogram of body weight. The best sources of fat include monounsaturated fats found in avocados, olives, and nuts, and polyunsaturated fats, particularly omega-3 fats found in salmon, trout, walnuts, and flax products. Athletes must minimize the intake of saturated and trans fats found in processed and high-fat meats.

For athletes who prioritize weight loss and body composition, the daily carbohydrate intake should be reduced to 3 to 4 grams per kilogram of body weight. Additionally, protein intake should be higher, ranging from 1.8 to 2.0 grams per kilogram of body weight per day, with an emphasis on branched-chain amino acids to enhance satiety and stabilize blood sugar levels. Athletes should continue to maintain fat intake around 0.8 grams per kilogram of body weight.

Fueling for Training Sessions During the Preparatory Cycle

Eating during training sessions in the preparatory cycle is crucial for maintaining hydration and carbohydrate stores. Nutrition recommendations can vary significantly based on factors such as environmental conditions, weight goals, sweat rate, and training load. These variables change as athletes progress through the preparatory training cycle, necessitating adaptable nutrition plans.

Hydration: Staying hydrated is the paramount consideration during training sessions in this cycle. Current hydration guidelines recommend drinking 0.07 to 0.10 ounces (2.1-3 ml) of fluid per pound (0.45 kg) of body weight four hours before training. Additionally, an extra 0.04 to 0.10 ounces (1.2-3 ml) of fluid per pound of body weight should be consumed two hours before training if the athlete’s urine isn’t pale yellow. For athletes training early in the morning, a more realistic recommendation is to consume at least 0.04 ounces (1.2 ml) of fluid per pound of body weight in the 30 to 45 minutes before training.

Carbohydrate Intake: For athletes not aiming to lose weight or body fat during the preparatory cycle, a recommended carbohydrate intake during training is 30 to 50 grams per hour. These recommendations are based on absolute values, not relative values (grams per kilogram of body weight). Since training sessions in this cycle are usually of low to moderate volume and low intensity, athletes do not require additional carbohydrates beyond these basic recommendations. Athletes can consume carbohydrates from a variety of sources, both solids (e.g., crackers, bananas, energy bars) and liquids (e.g., sports drinks, gels). Easily digestible carbohydrates are preferable, especially during low- to moderate-intensity exercises when blood flow to the stomach is adequate.

Protein: Protein intake is generally not required in large amounts during most training sessions in the preparatory cycle.

Hydration During Exercise: In general, athletes should aim to drink 3 to 8 ounces (89-237 ml) of fluid every 15 to 20 minutes during exercise to maintain hydration. However, sweat rates vary depending on the training environment, so this must be adjusted accordingly. Cyclists can usually absorb fluid at a higher rate than weight-bearing athletes such as runners due to differences in muscle mass and blood flow to the gut.

Weight Loss and Hydration: Athletes actively seeking weight loss can consider sports drinks containing electrolytes only for low-intensity training sessions shorter than 90 minutes. Maintaining a balance between fluid intake for hydration and avoiding overconsumption that might affect the subsequent running portion of training or racing is essential.

Post-Workout Nutrition: After training, athletes should aim to replace lost nutrients. Fluid, carbohydrate, protein, and sodium are the primary focus points for post-workout nutrition and should be consumed immediately after training, up to 60 minutes afterward. For fluids, athletes may need to consume more than what was lost to ensure adequate rehydration. Consuming 150 percent of fluid losses can help rehydrate the body effectively.

Post-Workout Carbohydrates: For glycogen-depleting workouts lasting longer than 90 minutes or featuring very high-intensity intervals, consuming carbohydrates with a higher glycemic index can enhance recovery. Athletes should consume 1.0 to 1.2 grams of these high-glycemic carbohydrates per kilogram of body weight.

Post-Workout Protein: While not required at the same levels as carbohydrates, post-workout protein helps the body shift into positive protein balance. Athletes should aim to eat 10 to 20 grams of high-quality protein.

Post-Workout Fat: Fat is typically not needed in the immediate post-workout window of opportunity and should not be included immediately after exercise.

Sustained Recovery: Athletes not seeking weight loss should consume 1.0 to 1.2 grams of carbohydrates per kilogram of body weight every two hours for the next 6 to 8 hours after the initial carbohydrate intake. Smaller snacks or meals are preferred, maximizing glycogen repletion without overfilling the athlete. The focus should be on less processed and refined carbohydrates in balanced snacks or meals.

These nutrition practices aim to align dietary intake with the energy demands of the athlete during different phases of the training cycle, ultimately supporting performance and recovery.

Nutrition for the Competition Cycle

The competition cycle in endurance sports typically encompasses two phases: the build (precompetition) and race (competition) components. During the build phase, athletes focus on high-intensity, high-volume training to enhance speed, power, and sport-specific strength. This phase adds considerable stress to the body, necessitating a strong focus on recovery. The training intensity and volume remain high during the competition cycle. Therefore, athletes are advised not to actively pursue weight loss during this phase. Caloric restriction can hinder the body’s ability to maintain high output levels and recover effectively after intense training.

Common mistakes during the competition season include not eating frequently enough, making poor food choices, and insufficient fluid intake. Athletes should avoid significantly altering their nutrition plan during this time.

In this phase, daily carbohydrate intake should be elevated compared to the previous training cycle, ranging from 7 to 10 grams per kilogram of body weight. Athletes engaged in extreme training may even require over 10 grams per kilogram to meet glycogen resynthesis needs.

The recommended daily protein intake remains moderate, ranging from 1.2 to 1.7 grams per kilogram of body weight. Athletes engaging in frequent, intense speed and strength training sessions may opt for the higher end of this range.

The range for daily fat intake remains similar to the preparatory cycle, except for ultradistance athletes who may require up to 1.5 grams per kilogram of body weight due to the higher energy expenditure during longer training sessions. Athletes are encouraged to focus on healthier fats, specifically omega-3 and monounsaturated fats, and minimize saturated and trans fats in their diet.

Fueling for Training Sessions during the Competition Cycle

During the competition cycle, fueling for training sessions is essential for optimizing workout effectiveness, ensuring proper recovery, and preventing or minimizing gastrointestinal (GI) distress during training and racing. Athletes should start sessions properly hydrated and with normal muscle glycogen levels. During the session, the goal is to maintain fluid, electrolyte, and blood glucose levels. Post-workout nutrients play a crucial role in the body’s recovery from training stress.

To avoid GI distress during training and racing, athletes should rely on their previous experiences to understand how their bodies respond to various types and quantities of foods and sport nutrition products. These experiences should guide their nutrition choices in this training cycle.

Recent research suggests that consuming a large amount (144 grams) of carbohydrate per hour during exercise can increase the body’s ability to use this fuel for energy. However, such high carbohydrate intake may not be practical for all athletes and should be tested during training sessions simulating race intensity. Recommendations for athletes during the competition cycle typically suggest consuming 30 to 90 grams of carbohydrate per hour during training and competitions. Smaller athletes, particularly females, may opt for lower quantities, while larger athletes could aim for higher amounts.

Post-glycogen-depleting workouts, athletes should follow the same nutrition guidelines as in the preparatory cycle, with a focus on consistency. Athletes should treat their post-workout nutrition regimen as an integral part of their training session, ensuring they do not forget or delay it. This consistency is vital for effective recovery and preparation for subsequent training sessions and competitions.

Nutrition for the Transition or Off-Season Cycle

The off-season is a period of rest, recovery, and rejuvenation for most athletes. However, it’s also a phase where some nutritional mistakes can lead to unnecessary body fat gain. These errors often occur when athletes do not maintain their focus on controlled, high-quality food intake. In the off-season cycle, the primary nutritional goal should be to control the quantity of food consumed while emphasizing the maintenance of stable blood sugar levels. Achieving this is primarily done through the consumption of lean protein and fiber-rich foods, with fruits and vegetables being preferred choices.

In contrast to specific training plans in other cycles, the off-season usually involves unstructured exercise. As a result, products such like energy bars, gels, sports drinks, and powders are generally not necessary. Given the lower energy requirements, daily carbohydrate intake decreases to as low as 3 to 4 grams per kilogram of body weight, with an emphasis on fruits and vegetables rather than whole grains and healthier starches. Daily protein intake should range from 1.6 to 2.0 grams per kilogram of body weight, while daily fat intake should remain low at 0.8 to 1.0 grams per kilogram of body weight, with an emphasis on omega-3 fats.

Fueling for Exercise Sessions during the Transition or Off-Season Cycle

During the transition or off-season cycle, training involves lower energy expenditure as training intensity and volume are reduced, and there are no specific training improvement goals. Athletes should prioritize being nourished and hydrated before exercise, typically by consuming a light, balanced meal or snack. During exercise, an athlete may require no more than 8 ounces (~237 ml) of water every 20 to 30 minutes. If necessary, small amounts of sodium (about 500 milligrams per liter of water) may be added to aid in maintaining hydration status.

After exercise, the focus should be on replenishing hydration stores by consuming 24 ounces (710 ml) of water with at least 500 milligrams of sodium per liter of water immediately after the workout. To enhance post-workout recovery, athletes can opt for a light snack or meal that is low in fat and includes a good source of carbohydrates along with some lean protein.

Ergogenic Aids

Ergogenic aids can be a source of confusion among athletes, often related to concerns about their safety and efficacy. These aids are not classified as macro- or micronutrients, which leads many people to think of them solely as performance enhancers for specific sports. While studies have provided valuable data supporting the performance- and recovery-enhancing effects of certain ergogenic aids, a comprehensive review of these supplements is beyond the scope of this section.

Athletes seeking more information on ergogenic aids can refer to specialized texts on the topic, such as “Power Eating, Third Edition” by Susan Kleiner with Maggie Greenwood-Robinson or “Advanced Sports Nutrition, Second Edition” by Dan Benardot. These texts offer in-depth insights into potential ergogenic aids. It’s essential for athletes to use these aids under the close supervision of a qualified health professional and to have a clear understanding of the potential risks associated with their use.