Vitamin and mineral intake are also important considerations for endurance athletes. Micronutrients are essential for optimal metabolic health, as various vitamins and minerals support functions like energy production, muscle growth, and recovery, all of which are central to performance for endurance athletes.

Carbohydrates are an important macronutrient for endurance performance, as they provide a simple source of fuel for immediate energy production. Additionally, carbohydrate intake has been linked to immune health benefits in endurance athletes, and intake may also improve the bioavailability of other supplements, such as protein supplements, that are needed for athletes to meet their energy demands.

While some endurance athletes may strategically train with lower-carbohydrate intake to improve fat oxidation and aerobic capacity, current research still points to carbohydrates as an essential energy source for endurance sports, particularly during higher-intensity training.

While protein and fat can still provide energy, carbohydrates are most efficiently metabolized by the body and can be broken down quickly enough to be used intra-exercise by endurance athletes. Carbohydrates also help to replenish glycogen stores, with carbohydrate loading strategies primarily aimed at optimizing glycogen supply before an event.

Inadequate glycogen reserve has been linked to a negative impact on performance in endurance athletes, especially during periods of strenuous training or competition. Rapidly absorbed, simple carbohydrates such as rice, potatoes, honey, or fruit are typically recommended over whole-grain, high-fiber carbohydrates for loading protocols.

Endurance exercise has been found to alter protein metabolism and can lead to hypertrophy of skeletal muscle, making protein intake post-training essential for recovery and adaptation to training.

Prolonged endurance training sessions also stimulate the oxidation of amino acids for energy, particularly branched-chain amino acids BCAAs.

For this reason, it can be beneficial for endurance athletes to consume adequate essential amino acids to not only repair exercise-induced muscle damage but also to supply supplemental energy for longer training sessions. Nutrition consensus statements from various dietetic associations state that athletes should aim for a protein intake of 1.

However, some studies suggest that a higher protein intake, upwards of 2 grams per kilogram of body weight, may be more beneficial for endurance athletes to maintain protein balance and meet training needs. Post-training or event sessions, protein intake accompanied by dietary fiber may be a good strategy to help prolong the availability of amino acids for endurance athletes.

Endurance athletes may have a longer post-training window for protein synthesis than found with resistance training, so dividing up protein intake between two meals within a 6-hour window for ongoing protein synthesis may also be ideal.

Readily digestible sources of protein with a high leucine content, such as grass-fed whey protein, are ideal for maximizing muscle protein synthesis after a training session.

While carbohydrate intake is often a focal point for endurance athletes, dietary fat intake is important for overall health, including optimal hormone function as well as serving as another energy source.

Endurance athletes can use nutritional strategies alongside training to help improve their metabolic flexibility, or the ability to switch between carbohydrates and fat-burning for energy production. Metabolic flexibility may be particularly beneficial towards the end of longer sessions or races, where glycogen reserves are depleted.

It may be best to consume dietary fats away from training sessions to minimize gastrointestinal distress, having them after training sessions but avoiding pre-session and peri-session fat intake. For any athlete, the longer the training session is, the more important hydration becomes as the risk increases for dehydration, salt loss, and an overall negative impact on body water balance.

No one recommendation can be applied to all athletes due to differences in training load, sweat rate, body mass, and other factors; however, the following recommendations apply to most endurance athletes and can help determine individual fluid intake needs.

First, measuring body weight before and after training can help to estimate the amount of water loss experienced during activity, so an athlete can replace fluids accordingly. Second, athletes should pay attention to urine it should be a pale color and thirst sensation it should be low to ensure hydration is adequate before training.

Micronutrients may help boost mental performance while competing, as well as supporting hormone production and overall cognitive function.

Female athletes are less likely to meet their iron intake requirements, and may also have lower levels of other micronutrients important to both overall health and athletic performance, including choline, selenium, zinc, and vitamin B Three specific micronutrients that are especially important for endurance athletes are iron, magnesium, and calcium.

Iron is an important mineral for endurance athletes, as iron deficiency anemia can hurt athletic performance. Athletes are more prone to iron-deficiency anemia than the general population, due to post-training inflammation, sweating, training intensity and muscle repair, and a higher need for nutrient intake in general.

While iron supplementation and increasing the frequency of iron-rich foods in the diet is most helpful for athletes who have deficiencies , low-dose iron supplementation even in non-anemic endurance athletes has been shown to help improve training-related stress, mood, and fatigue.

Magnesium benefits endurance athletes due to its impact on blood pressure, heart rate, and VO2 max. Even a slight magnesium deficiency can impact endurance exercise performance and may amplify the oxidative stress that naturally occurs with intense exercise.

Additionally, the need for magnesium increases with higher levels of physical exertion, making magnesium needs for endurance athletes higher than that of the general population. A third example of a micronutrient important for endurance athletes is calcium.

Calcium is important to optimize bone health in athletes, though is also important for heart function and neuromuscular coordination. Calcium losses may also occur with excessive sweating during longer endurance events, making it an important micronutrient to track and replace as needed.

Other supplementations common amongst endurance athletes include caffeine, antioxidants, probiotics , protein supplements, and nitrates beetroot powder or juice. When it comes to nutrition strategies for different types of endurance events, the use of periodized nutrition by athletes and coaches can help personalize a training and recovery program.

Periodized nutrition refers to the strategic combination of exercise and nutrition to optimize performance, meaning that nutritional strategies may vary with types of training depending on the goal of each athlete, versus eating the same way constantly. Strategies may vary between types of race events as well.

An example of this concept can be explained by looking at strategies for triathletes. During triathlons, carbohydrates tend to be the primary fuel to ensure easy access to an energy source throughout a fairly long race event.

Electrolytes or salt must also be replaced based on the sweat rate of the athletes, in addition to ensuring ongoing fuel intake. For race times in the Athletes may strategically consume carbohydrates more in the cycle portion of the triathlon, through carbohydrate drinks, gels, or bars, as it tends to be easier to consume while seated on a bike.

While it can seem daunting to consider all of the different nutritional strategies an endurance athlete can employ to support optimal energy and performance, there are a few basic concepts that are simple to follow that will help to maintain proper nutrition. Prioritizing carbohydrates, fluids, and electrolytes during pre- and peri-training sessions helps minimize the risk of dehydration and ensures an ongoing, accessible fuel source to tap into for athletes.

A well-planned hydration strategy that is practiced during training can help make race day much more efficient. Protein intake should also be a focus, with post-workout protein intake particularly important to support muscle recovery and training adaptations.

Fat and fiber intake are important for overall health but may be best consumed away from training windows to minimize gastrointestinal discomfort during the race or training session. Endurance athletes may face a few different nutritional challenges when it comes to optimizing their race-day performance.

Common challenges include eating enough calories to meet training demands, as well as consuming enough key nutrients such as protein, calcium, and iron. The timing of food intake can also be challenging, as athletes want to consume food within a timeframe to optimize performance, but also simultaneously minimize gastrointestinal symptoms like bloating, stomach cramps, or needing to have a bowel movement while racing.

Athletes, especially female athletes, are at a higher risk for RED-S , or Relative Energy Deficiency in Sports, which can be a consequence of continually not meeting caloric needs and having low energy availability.

RED-S can lead to poor recovery, poor adaptation to training, hormone imbalances, decreased immunity, and in severe cases compromise of bone health. To prevent and address these challenges, endurance athletes can incorporate several things into their training programs.

Smart use of supplementation, guided by personalized lab testing, can help address any nutrient gaps identified in their diet alone, especially in athletes who may have dietary restrictions.

Additionally, trying out different methods of meal timing and macronutrient intake around training sessions can help athletes identify which feeding schedules work best for their performance and recovery, helping to plan out race day strategies. For example, athletes may want to emphasize carbohydrates and protein closer to their training windows, while reserving fat and fiber intake for post-training meals to ensure they hit their overall dietary needs without compromising feeling their best during a session.

Athletes must also consider meal timing pre- and post-training, as well as during training, as many endurance athletes are participating in sessions that can last for multiple hours.

A nutrient-dense, balanced diet that covers macro- and micronutrient needs is important for optimal performance, sustained energy, and recovery and training adaptation. Achten, J. Higher dietary carbohydrate content during intensified running training results in better maintenance of performance and mood state.

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Early postexercise muscle glycogen recovery is enhanced with a carbohydrate-protein supplement. Journal of Applied Physiology , 93 4 , — Kanter, M. High-Quality Carbohydrates and Physical Performance. Nutrition Today , 53 1 , 35— Kapoor, M. Influence of iron supplementation on fatigue, mood states and sweating profiles of healthy non-anemic athletes during a training exercise: A double-blind, randomized, placebo-controlled, parallel-group study.

Contemporary Clinical Trials Communications , 32 , Kato, H. Protein Requirements Are Elevated in Endurance Athletes after Exercise as Determined by the Indicator Amino Acid Oxidation Method. PLOS ONE , 11 6 , e Knuiman, P. Protein and the Adaptive Response With Endurance Training: Wishful Thinking or a Competitive Edge?

Frontiers in Physiology , 9. In fact, it is well documented that almost any induction of an energy deficit leads the downregulation of energy-expending processes to conserve energy in efforts to further minimize the energy gap between intake and expenditure, a phenomenon referred to as adaptive thermogenesis While adaptive reductions in RMR in response to energy restriction have been documented in numerous longitudinal studies in various populations 1 , 12 , 13 , 25 , cross-sectional approaches to identify athletes whose RMR is chronically suppressed are much more challenging, as RMR is highly variable between individuals One particular problem is the lack of suitable prediction equations for athletic populations, as prominent equations e.

Harris-Benedict, Cunningham, Mifflin-St. Jeor fail to account for the unique body composition of athletes 21 , 37 , thereby potentially under- or overestimating their RMR substantially. To overcome this issue, we have implemented a novel approach Figure 1 which combines advanced whole-body imaging with indirect calorimetry In short, we compare RMR measured via indirect calorimetry with RMR predicted from the size of the primary tissues and organs contributing to whole-body energy expenditure inner organs, brain, skeletal muscle, adipose tissue, bone using established tissue-coefficients While amenorrhea represents a clear clinical sign which has been linked to energy deficiency for many years 20 , its diagnosis in female athletes involves the exclusion of other causes 4.

Further, subclinical menstrual disturbances which may go unnoticed by the athletes, have also been linked to energy status 3. As such, the confirmation of RMR suppression can provide additional evidence for the role of energy deficiency in the etiology of menstrual disturbances, especially since it involves tools commonly available to sports nutrition practitioners.

Further, energy deficiency is more likely to go unnoticed in male athletes, whose reproductive function appears to be less vulnerable by energy status 32 , as well as female athletes using hormonal contraception. In these cases, RMR measurements may be a first step in the detection of energy deficiency.

In fact, unpublished data from various athlete and non-athlete groups suggests that other at-risk groups, such as male athletes involved in leanness sports 8 , exhibit similar reductions in RMR.

Confirmation of energy deficiency may complement available screening tools and make it easier for athletes and their support staff to adopt appropriate dietary treatment approaches 5 , 22 , While quantifying RMR reduction may be an important tool to detect chronically energy-deprived athletes, the RMR reduction is nothing but the product of underlying metabolic adaptations, i.

a symptom. Therefore, other metabolic, endocrine or clinical markers are required to determine causal and mechanistic factors contributing to RMR suppression.

In amenorrheic athletes, the RMR suppression was not only associated with the suppression of the reproductive hormones estrogen and progesterone, it also correlated with reductions in key metabolic hormones, such as leptin and T3 These findings provide real-life evidence of previous seminal studies by Anne Loucks and colleagues who established a direct and dose-dependent relationship between energy availability and alterations in hormones related to energy status e.

Furthermore, there is increasing evidence that physical performance is also impacted by energy deficiency. However, as prospective experiments are challenging if not prohibitive in competitive athletes, most of the knowledge on the potentially detrimental effects of energy deficiency on performance is derived from observational studies.

For example, Van Heest et al. followed a group of young elite female swimmers during a week training period. In light of the connection between energy status and menstrual health, swimmers were retrospectively divided into groups based on their menstrual status.

Further, swimmers with menstrual disturbances demonstrated endocrine evidence of low energy availability, including reduced concentrations of thyroid hormones and IGF A similar study was recently published by Woods et al. As a result, athletes lost weight Analysis of 5-km time trial data demonstrated a 3.

Despite the above mentioned negative effects on health and performance of athletes, acute or chronic states of energy deficiency remain a part of competitive sports.

Reasons for this continued problem include seasonal variations in training volume, the need to lose weight or improve body composition, and regulations or traditions in specific sports, including light weight rowing.

For example, shifting weight loss away from functional tissues, such as skeletal muscle and bone, towards the loss of adipose tissue has the potential to maintain functional capacity This can be achieved using exercise as a stimulus to preserve muscle mass, as data from our lab demonstrates.

Young, healthy and endurance-trained men underwent repeated periods of severe energy deficiency, once with incorporation of exercise and once without exercise.

To maintain equicaloric conditions, participants were compensated for the additional energy cost of the prescribed exercise Despite similar reductions in body weight and fat mass, the incorporation of exercise preserved lean mass Figure 3 and prevented declines in submaximal performance indices and indices of well-being A recent follow-up study suggest that these beneficial effects can be expanded by combining exercise with elevated protein intake 1.

Although it may be challenging to incorporate more exercise into the training schedule of most athletes, these data highlight the importance of maintaining an effective exercise regimen.

The fact that the preventative effects of exercise on lean mass occurred predominantly in the exercised extremities suggest that exercise can be targeted exercise to protect specific muscle sites. Further, recent reports on sedentary behavior among elite level rowers 38 suggest that at least some targeted exercise can be incorporated into the lifestyle of competitive rowers, given that this does not interfere with their recovery.

Given the significance of adaptive reductions in energy expenditure, changes in body weight alone are insufficient measures of energy status. However, additional strategies may be needed to address other components of the RED-S framework which might be negatively impacted by energy deficiency.

Conflict of Interest The authors have no conflict of interest. Home Archive Archive Issue 1 Energy Deficiency and Nutrition in Endurance Sports — Focus on Rowing. DOI:

Intentional attempts to achieve weight gain via an energy surplus are rare and challenging 7. However, the likelihood of athletes entering a negative energy balance is much higher, whether it is through reducing dietary intake to achieve or maintain a low body weight in sports with weight limitations e.

lightweight rowing , endurance sports, or anti-gravity sports, as the result of disordered eating and clinical eating disorders, or the inability to match the increased expenditure as a result of training and competition The etiology as well as the consequences of chronic energy deficiency, i.

a long-term mismatch between energy intake and expenditure, have been reviewed extensively in the context of the female athlete triad 5 , and more recently under the term relative energy deficiency in sports RED-S , a more encompassing approach to include a broader athletic population and numerous health-related outcomes aside from bone and menstrual health 22 , In contrast, the purpose of the present mini-review, which resulted from an invited presentation at the World Rowing Conference held in Berlin, Germany, was to highlight issues specific to endurance sports and more specifically rowing, with a special emphasis on practical approaches for the detection of energy-deficient athletes and strategies to alleviate some of the effects detrimental to athletic performance.

Textbook knowledge suggests that a negative energy balance results in weight loss via the mobilization of energy stores from fat and lean tissues in efforts to balance the imposed energy deficit 9.

In addition to providing energy, the loss of metabolically active body tissue also results in a reduction in energy expenditure, thereby reducing the initial energy deficit However, this reduction is typically not sufficient to balance the imposed deficit completely and therefore requires additional reductions in TDEE to return to a physiologically preferential state of equilibrium at a lower set-point.

In fact, it is well documented that almost any induction of an energy deficit leads the downregulation of energy-expending processes to conserve energy in efforts to further minimize the energy gap between intake and expenditure, a phenomenon referred to as adaptive thermogenesis While adaptive reductions in RMR in response to energy restriction have been documented in numerous longitudinal studies in various populations 1 , 12 , 13 , 25 , cross-sectional approaches to identify athletes whose RMR is chronically suppressed are much more challenging, as RMR is highly variable between individuals One particular problem is the lack of suitable prediction equations for athletic populations, as prominent equations e.

Harris-Benedict, Cunningham, Mifflin-St. Jeor fail to account for the unique body composition of athletes 21 , 37 , thereby potentially under- or overestimating their RMR substantially. To overcome this issue, we have implemented a novel approach Figure 1 which combines advanced whole-body imaging with indirect calorimetry In short, we compare RMR measured via indirect calorimetry with RMR predicted from the size of the primary tissues and organs contributing to whole-body energy expenditure inner organs, brain, skeletal muscle, adipose tissue, bone using established tissue-coefficients While amenorrhea represents a clear clinical sign which has been linked to energy deficiency for many years 20 , its diagnosis in female athletes involves the exclusion of other causes 4.

Further, subclinical menstrual disturbances which may go unnoticed by the athletes, have also been linked to energy status 3. As such, the confirmation of RMR suppression can provide additional evidence for the role of energy deficiency in the etiology of menstrual disturbances, especially since it involves tools commonly available to sports nutrition practitioners.

Further, energy deficiency is more likely to go unnoticed in male athletes, whose reproductive function appears to be less vulnerable by energy status 32 , as well as female athletes using hormonal contraception. In these cases, RMR measurements may be a first step in the detection of energy deficiency.

In fact, unpublished data from various athlete and non-athlete groups suggests that other at-risk groups, such as male athletes involved in leanness sports 8 , exhibit similar reductions in RMR.

Confirmation of energy deficiency may complement available screening tools and make it easier for athletes and their support staff to adopt appropriate dietary treatment approaches 5 , 22 , While quantifying RMR reduction may be an important tool to detect chronically energy-deprived athletes, the RMR reduction is nothing but the product of underlying metabolic adaptations, i.

a symptom. Therefore, other metabolic, endocrine or clinical markers are required to determine causal and mechanistic factors contributing to RMR suppression. In amenorrheic athletes, the RMR suppression was not only associated with the suppression of the reproductive hormones estrogen and progesterone, it also correlated with reductions in key metabolic hormones, such as leptin and T3 These findings provide real-life evidence of previous seminal studies by Anne Loucks and colleagues who established a direct and dose-dependent relationship between energy availability and alterations in hormones related to energy status e.

Furthermore, there is increasing evidence that physical performance is also impacted by energy deficiency.

However, as prospective experiments are challenging if not prohibitive in competitive athletes, most of the knowledge on the potentially detrimental effects of energy deficiency on performance is derived from observational studies.

For example, Van Heest et al. followed a group of young elite female swimmers during a week training period. In light of the connection between energy status and menstrual health, swimmers were retrospectively divided into groups based on their menstrual status.

Further, swimmers with menstrual disturbances demonstrated endocrine evidence of low energy availability, including reduced concentrations of thyroid hormones and IGF A similar study was recently published by Woods et al.

As a result, athletes lost weight Analysis of 5-km time trial data demonstrated a 3. Despite the above mentioned negative effects on health and performance of athletes, acute or chronic states of energy deficiency remain a part of competitive sports.

Reasons for this continued problem include seasonal variations in training volume, the need to lose weight or improve body composition, and regulations or traditions in specific sports, including light weight rowing.

For example, shifting weight loss away from functional tissues, such as skeletal muscle and bone, towards the loss of adipose tissue has the potential to maintain functional capacity This can be achieved using exercise as a stimulus to preserve muscle mass, as data from our lab demonstrates.

Young, healthy and endurance-trained men underwent repeated periods of severe energy deficiency, once with incorporation of exercise and once without exercise. To maintain equicaloric conditions, participants were compensated for the additional energy cost of the prescribed exercise Despite similar reductions in body weight and fat mass, the incorporation of exercise preserved lean mass Figure 3 and prevented declines in submaximal performance indices and indices of well-being The unexplored crossroads of the female athlete triad and iron deficiency: a narrative review.

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FormalPara Key Points While the effects of high altitude on the endocrine systems, energy intake, resting metabolic rate and body mass are severe, it appears that resting metabolic rate is also increased, albeit to a smaller extent, at low to moderate altitudes, and targeting adequate energy intake is important for optimizing health and appears to be an emerging factor associated with optimizing altitude adaptations.

Full size image. References Mujika I, Sharma AP, Stellingwerff T. Article Google Scholar Wilber RL. Google Scholar Bonetti DL, Hopkins WG. PubMed Google Scholar Saunders PU, Pyne DB, Gore CJ. PubMed Google Scholar Chapman RF, Karlsen T, Resaland GK, et al. PubMed Google Scholar Gore CJ, Clark SA, Saunders PU.

PubMed Google Scholar Chapman RF, Laymon Stickford AS, Lundby C, et al. PubMed Google Scholar Bartsch P, Saltin B. PubMed Google Scholar Stellingwerff T, Pyne DB, Burke LM.

PubMed Google Scholar Meyer NL, Manore MM, Helle C. PubMed Google Scholar Bergeron MF, Bahr R, Bartsch P, et al. CAS PubMed Google Scholar Hawley JA, Gibala MJ, Bermon S.

Intentional attempts to achieve weight gain via an energy surplus are rare and challenging 7. However, the likelihood of athletes entering a negative energy balance is much higher, whether it is through reducing dietary intake to achieve or maintain a low body weight in sports with weight limitations e.

lightweight rowing , endurance sports, or anti-gravity sports, as the result of disordered eating and clinical eating disorders, or the inability to match the increased expenditure as a result of training and competition The etiology as well as the consequences of chronic energy deficiency, i.

a long-term mismatch between energy intake and expenditure, have been reviewed extensively in the context of the female athlete triad 5 , and more recently under the term relative energy deficiency in sports RED-S , a more encompassing approach to include a broader athletic population and numerous health-related outcomes aside from bone and menstrual health 22 , In contrast, the purpose of the present mini-review, which resulted from an invited presentation at the World Rowing Conference held in Berlin, Germany, was to highlight issues specific to endurance sports and more specifically rowing, with a special emphasis on practical approaches for the detection of energy-deficient athletes and strategies to alleviate some of the effects detrimental to athletic performance.

Textbook knowledge suggests that a negative energy balance results in weight loss via the mobilization of energy stores from fat and lean tissues in efforts to balance the imposed energy deficit 9.

In addition to providing energy, the loss of metabolically active body tissue also results in a reduction in energy expenditure, thereby reducing the initial energy deficit However, this reduction is typically not sufficient to balance the imposed deficit completely and therefore requires additional reductions in TDEE to return to a physiologically preferential state of equilibrium at a lower set-point.

In fact, it is well documented that almost any induction of an energy deficit leads the downregulation of energy-expending processes to conserve energy in efforts to further minimize the energy gap between intake and expenditure, a phenomenon referred to as adaptive thermogenesis While adaptive reductions in RMR in response to energy restriction have been documented in numerous longitudinal studies in various populations 1 , 12 , 13 , 25 , cross-sectional approaches to identify athletes whose RMR is chronically suppressed are much more challenging, as RMR is highly variable between individuals One particular problem is the lack of suitable prediction equations for athletic populations, as prominent equations e.

Harris-Benedict, Cunningham, Mifflin-St. Jeor fail to account for the unique body composition of athletes 21 , 37 , thereby potentially under- or overestimating their RMR substantially.

To overcome this issue, we have implemented a novel approach Figure 1 which combines advanced whole-body imaging with indirect calorimetry In short, we compare RMR measured via indirect calorimetry with RMR predicted from the size of the primary tissues and organs contributing to whole-body energy expenditure inner organs, brain, skeletal muscle, adipose tissue, bone using established tissue-coefficients While amenorrhea represents a clear clinical sign which has been linked to energy deficiency for many years 20 , its diagnosis in female athletes involves the exclusion of other causes 4.

Further, subclinical menstrual disturbances which may go unnoticed by the athletes, have also been linked to energy status 3. As such, the confirmation of RMR suppression can provide additional evidence for the role of energy deficiency in the etiology of menstrual disturbances, especially since it involves tools commonly available to sports nutrition practitioners.

Further, energy deficiency is more likely to go unnoticed in male athletes, whose reproductive function appears to be less vulnerable by energy status 32 , as well as female athletes using hormonal contraception.

In these cases, RMR measurements may be a first step in the detection of energy deficiency. In fact, unpublished data from various athlete and non-athlete groups suggests that other at-risk groups, such as male athletes involved in leanness sports 8 , exhibit similar reductions in RMR.

Confirmation of energy deficiency may complement available screening tools and make it easier for athletes and their support staff to adopt appropriate dietary treatment approaches 5 , 22 , While quantifying RMR reduction may be an important tool to detect chronically energy-deprived athletes, the RMR reduction is nothing but the product of underlying metabolic adaptations, i.

a symptom. Therefore, other metabolic, endocrine or clinical markers are required to determine causal and mechanistic factors contributing to RMR suppression. In amenorrheic athletes, the RMR suppression was not only associated with the suppression of the reproductive hormones estrogen and progesterone, it also correlated with reductions in key metabolic hormones, such as leptin and T3 These findings provide real-life evidence of previous seminal studies by Anne Loucks and colleagues who established a direct and dose-dependent relationship between energy availability and alterations in hormones related to energy status e.

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To prevent and address these challenges, endurance athletes can incorporate several things into their training programs. Smart use of supplementation, guided by personalized lab testing, can help address any nutrient gaps identified in their diet alone, especially in athletes who may have dietary restrictions.

Additionally, trying out different methods of meal timing and macronutrient intake around training sessions can help athletes identify which feeding schedules work best for their performance and recovery, helping to plan out race day strategies.

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