Rather, the challenge lies in covering the distance within a limited timeframe. Most everyone reading this article could complete miles in several days without much issue; however, running miles in less than 30 hours would be a much greater test.

Add to this the component of competition, and the objective becomes even more demanding. In order to finish under cutoffs and race well against your peers, you must perfect your ability to run at a steady pace for a long period of time. Stamina-based workouts help you achieve this through lactate threshold improvement and learning to run by effort — two essential skills when racing on rough trails or hilly road courses.

Ashley Nordell finishing strong at the Lake Sonoma 50 Mile. Blood lactate is formed through any simple muscle movement. During light activity, the body is able to rid the muscles of the small amount of lactate created. However, at higher exercise intensities, muscles are flooded with lactate and a point is eventually reached at which the body cannot clear the large amounts of lactate created.

We are all familiar with this feeling: burning muscles, the inability to produce power, and the inevitable need to slow down. Lactate threshold LT , the most important determinant for endurance athlete success, has been reached. Keep in mind that stamina-based training is not speedwork.

In fact, the most difficult aspect of LT improvement is to keep from running these workouts too quickly. Pushing yourself to go longer at a given pace rather than faster is the key component. In general, LT is attained near a one-hour race pace and stamina-based training focuses on working at or near this point.

Running too fast will only tire you and shorten the amount of time you are able to hold your effort within this beneficial range. Unlike your endurance-based workouts , stamina-based workouts require to minute warmup and cooldown periods. Twenty minutes at a steady state pace will provide training benefits early in the training cycle, but as your fitness improves, work up to an hour or more.

The tempo run is probably the most misinterpreted workout in the running community. Tempo runs are more intense and thus shorter in duration than steady state runs. They last between 15 and 40 minutes and are performed at LT, which is between a to minute race pace.

For most, this is achieved at nearly 12k to half-marathon race pace. I started feeling more comfortable again for this training block.

I hope that continues. It just transfers to your efficiency in running on everything. Jim Walmsley on the way to his mile world record in Photo: Hoka.

If you find the length of tempo runs tough to recover from or just too daunting, try tempo intervals as a way to increase your stamina. Importantly, although ultra-endurance athletes have a reasonable knowledge of nutrition, they tend to favour the insights of other athletes over qualified nutrition experts [ 21 ].

Accordingly, the aim of this paper is to provide an accessible, evidence-based Position Stand on the nutritional considerations of ultra-marathon training and racing to inform best-practice of athletes, coaches, medics, support staff, and race organizers.

This is particularly pertinent given the increased participation in ultra-marathon racing across the globe, and the ever-expanding extremes of race demands. This Position Stand is concerned primarily with the nutritional considerations for single-stage ultra-marathon training and racing.

Articles were searched via three online databases Pubmed, MEDLINE, and Google Scholar , and the main search-terms comprised various combinations of the following: extreme-endurance, hydration, marathon, nutrition various terms , pathophysiology, physiology, supplements various terms , ultra-marathon, and ultra-endurance.

The reference-lists of those articles selected for inclusion were manually searched for additional literature.

The data informing our recommendations are incomplete, particularly relative to other sports, for several reasons. Firstly, despite the growing popularity of ultra-marathon, participant numbers are still relatively low.

Secondly, ultra-marathons are often contested in remote locations and environmental extremes which do not lend themselves to complex or invasive data-collection protocols, especially when requiring equipment that is difficult to transport.

For this review, therefore, the decision was made to include all published studies that were relevant to the topic, irrespective of any methodological concerns that may have arisen e.

We have, nevertheless, been clear with respect to methodological limitations of the studies included. Furthermore, we have graded the strength of our evidence statements according to the system employed by the National Heart, Lung, and Blood Institute NHLBI [ 22 ] , which we have adapted to incorporate a fourth level pertinent to case-reports.

The system in question has also been used by other nutrition-related reviews [ 23 ]. Table 1 is a summary of the grading system and evidence categories. The foremost nutritional challenge facing the ultra-marathon runner is meeting the daily caloric demands necessary to optimize recovery and permit prolonged and repeated training sessions [ 24 ].

From a metabolic perspective, ultra-marathon racing places a heavy dependence on oxidative metabolism to utilize glycogen and fat stores efficiently; moreover, with increasing race distance, there is a substantial increase in the use of free fatty acids as fuel [ 25 ].

Therefore, a central aim of any periodized ultra-marathon training program should be to maximize capacity for fat metabolism, thereby sparing muscle glycogen for the latter stages of competition. Given that training volume and intensity will vary throughout the season, the energy and macronutrient intake must be periodized to accommodate variable training loads.

Careful consideration of the weekly requirements of both training and recovery is recommended to achieve energy balance, unless there is an individual goal of weight loss or gain. In addition, when nutritional intake cannot be matched e.

When expressed relative to body mass, ultra-marathon runners undertaking frequent bouts of intense training e. With respect to macronutrient breakdown, Table 3 provides estimated daily requirements for individuals completing training runs at However, for athletes with greater caloric requirements, relative protein intakes up to 2.

Unless strategically targeting a ketogenic approach, fat intakes ranging from 1. The aim of ultra-marathon training should be to maximize fat metabolism in order to preserve muscle glycogen; therefore, nutrition strategies that promote or optimize fat oxidation should be prioritized.

Pre-exercise CHO intake also facilitates the uptake of blood glucose into muscle, and suppresses hepatic liver glycogenolysis [ 37 ], which may increase the potential risk of hypoglycaemia during the early period of a training session in susceptible individuals [ 38 ], although any negative impact of this on short-duration exercise performance has been refuted [ 39 ].

Others have reported hypoglycaemia-like symptoms during exercise that follows CHO intake [ 40 ] which may negatively impact athlete effort perceptions. Collectively, these data support the notion that athletes should aim to commence training in a euglycemic state [ 41 ].

These daily intakes are deemed necessary to restore muscle and liver glycogen, satisfy the metabolic needs of the muscles and central nervous system, and ensure CHO availability for days of successive training.

Nevertheless, a joint proposition from the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine [ 42 ] suggested that:. The notion of train-low, compete-high is based on insights from cellular biology suggesting that careful manipulation of glycogen via dietary CHO restriction can serve as a regulator of metabolic cell-signalling, which can optimize substrate efficiency and endurance adaptations [ 5 ].

This may be particularly beneficial in the early stages of a training regimen, thereby allowing sufficient time for adaptations to occur. Periodically training with low muscle glycogen is associated with the activation of signalling pathways, including AMPK, which play a crucial role in mitochondrial biogenesis.

Importantly, this regulates key transporter proteins including glucose transporter-4 GLUT-4 and the monocarboxylate transporters, both of which mediate endurance performance for review, see [ 5 ]. Chronic training with lowered but not depleted glycogen stores can result in adaptations that, following glycogen resynthesis, increase total work and time to exhaustion during exercise [ 43 ].

The above-mentioned strategy has been scarcely studied in relation to ultra-marathon training and should, therefore, be practiced tentatively.

Indeed, safe implementation requires nutrition-specific knowledge, an understanding of training periodization, and a degree of experience and self-awareness on behalf of the athlete with respect to their requirements.

As such, athletes are cautioned against training in a chronically depleted state especially during intensive training periods, or when repeated days of prolonged training are scheduled as this may lead to low energy availability and, ultimately, relative energy deficiency RED-S [ 46 ];.

A further consideration is that high-intensity performance will likely be compromised by low glycogen availability, due to a relative inability to sustain a high work rate [ 45 ]. The practice of periodic CHO moderation should, therefore, be preferred to restriction.

Another approach in modifying macronutrient intake to shift metabolic flexibility in favor of fat oxidation is the use of ketogenic diets. These have traditionally involved dramatic alterations in dietary fat utilizing a fat:protein or fat:carbohydrate ratio.

The term keto-adapted has been used to denote a metabolic shift towards efficient use of ketone bodies. While debate exists, keto-adaptation may take several weeks or months, indicating that sustained tolerance to high-fat intake may be necessary in order that the individual acquire the full benefits.

Various ketogenic strategies have been studied e. However, the subsequent impact of this change in substrate efficiency on exercise performance is unclear. Accordingly, a strict ketogenic diet may not be necessary to promote fat oxidation in ultra-marathon runners.

Notwithstanding the available research which indicates a degree of benefit, ketogenic diets have been associated with acute negative symptoms, including: fatigue, headaches, poor concentration, lethargy, GI discomfort, nausea, and weight loss.

All such symptoms may have consequences for training, particularly when resulting in immunosuppression and decreases in lean mass. Furthermore, it is plausible that runners training in a glycogen-depleted state, and who are insufficiently keto-adapted , may become acutely catabolic.

It should also be noted that significant increases in fat intake are often congruent with decreased intake of fiber and micronutrients specifically, iron, magnesium, potassium, folate, and antioxidants [ 51 ]. Previous studies into sustained ultra-endurance exercise have highlighted concerns with decreased intakes of some micronutrients magnesium and B-vitamins [ 52 , 53 ] and, as such, a mineral-rich approach involving plant-based foods and wholegrains should be incorporated into the overall nutrition strategy to support broader training requirements.

Finally, available data support the contention that while ketogenic approaches may enhance fuel utilization to favor fat oxidation, the ability to perform at higher intensities may be compromised, or even reduced, due to downregulation of pyruvate dehydrogenase [ 54 ], leading to reduced oxygen economy [ 55 ].

Despite positive anecdotal reports from ultra-marathon runners, there is insufficient literature to support the notion that sustained ketogenic diets are beneficial for performance, and caution is urged if following such a practice, especially when considering the influence of in-task CHO intake on substrate use during exercise.

Strategically moderating CHO intake can facilitate metabolic adaptations associated with enhanced endurance performance. However, caution is advised against training chronically glycogen depleted, particularly during periods of repeated high-intensity exercise or prior to racing.

Despite the use of ketogenic diets to facilitate a rapid metabolic shift towards greater fat oxidation, there is insufficient evidence to support the use of such diets in ultra-marathon training, and further research is warranted. Moreover, nitrogen balance can remain below baseline for several days following unaccustomed exercise [ 57 ].

The substantial training distances of ultra-marathon are associated with high levels of mechanical stress. This is reinforced by empirical data showing that whole-blood markers of muscle breakdown e.

The environmental terrain typical of ultra-marathon also deserves consideration in the training program. Downhill running on mountainous or undulating paths is associated with greater peak flexion angles relative to level or uphill running; this exaggerates the eccentric component of impact-loading, thereby increasing muscle damage [ 56 ].

Indeed, muscle damage resulting from a single bout of downhill running can result in a shortened stride-length in subsequent efforts [ 61 ], and this may be pertinent for runners training on consecutive days.

As such, although prior conditioning of the musculoskeletal system is critical for successful participation in ultra-marathon, participants should be mindful of nutritional strategies which may mitigate muscle damage and the associated inflammation during the training period.

Satisfying metabolic demand for protein is, therefore, a prerequisite for both recovery and general health. Contemporary guidelines for athletes engaged in chronic endurance training suggest dietary protein in the amount of 1.

Current evidence indicates that protein intakes of less than 1. Furthermore, amounts exceeding 2. This may, in turn, necessitate slightly higher intakes [ 64 ].

Runners should also be mindful that protein needs may be higher in older adults [ 67 , 68 ]. During chronic training, protein ingested before sleep appears to be an effective strategy to increase muscle protein synthesis overnight for review, see [ 70 ].

Ultra-marathon runners who struggle to meet their protein needs through dietary means might choose to supplement, perhaps using whey protein due to its high bioavailability and complete amino acid profile [ 63 ]. The branched-chain amino acids BCAAs have been the focus of study for many years.

An acute bout of prolonged exercise increases the rate of BCAA oxidation in skeletal muscle [ 71 ], suggesting that demands in ultra-marathon runners may be greater, but chronic training significantly attenuates the absolute rate of BCAA oxidation during exercise [ 71 ].

Therefore, the primary utility of BCAAs may be in muscle recovery and immune regulation during periods of hard training and racing [ 72 , 73 ], particularly when consumed in the post-absorptive state [ 74 ]. Although meeting absolute protein demand is critical for the ultra-marathon runner, the literature suggests that L-leucine may support the upregulation of muscle protein synthesis, influencing mRNA translation and the mTOR cell-signalling pathway [ 75 ].

Intakes of up to 2. A typical training session for the ultra-marathon runner appears sufficient to cause substantial dehydration. Over the half-marathon distance Over longer training distances marathon , high-level runners exhibited a body weight loss of 0.

Furthermore, abstaining from fluid resulted in an average dehydration of 3. Notwithstanding the commonly-reported effects of mild dehydration on subsequent exercise performance, chronic dehydration can influence health outcomes, with several authors noting dehydration-mediated changes in vasopressin, and markers of metabolic dysfunction or disease [ 8 ].

To mitigate carry-over effects from one session to the next, and to maintain general health, there are two components of hydration that warrant consideration in the periodized nutrition program: 1 hydration strategies to facilitate post-exercise recovery; and 2 day-to-day hydration requirements that are independent of training.

When recovery time is short, or the extent of fluid loss is great, thirst-driven fluid intake is not adequate to restore water balance [ 79 ].

Targeted fluid replacement strategies are, therefore, critical to maximize recovery before a subsequent session. It stands to reason that runners should replenish the fluid volume lost in training; this can be estimated via pre- to post-exercise body mass weighing.

However, even in a hypohydrated state, the obligatory excretion of metabolic waste products allows for continued fluid losses [ 80 ]. Consequently, a fluid volume greater than that lost in training is necessary to fully restore water balance.

This notion has been demonstrated empirically by both Shirreffs et al. As these data indicate, plain water is not likely sufficient to restore fluid balance following training due to the consequent decrease in plasma sodium concentration and osmolality [ 82 ] causing diuresis.

Unequivocally, post-exercise urine output decreases as the drink sodium concentration increases; sodium intake should, therefore, ideally equal the concentration of sodium lost in sweat.

There is little research on the suggested rate of fluid intake, but the available data indicate that slow consumption i. The actual fluid intake necessary to attain euhydration on a day-to-day basis will vary with renal and extrarenal water losses [ 85 ]; moreover, the absolute daily fluid intake from food and drink will vary widely among individuals.

There are also daily fluctuations in total body water, estimated by Cheuvront et al. Interestingly, using biochemical measures of blood and urine, average plasma osmolality was found to be similar between groups of low-volume 1.

Indeed, elite Kenyan endurance runners have been shown to exhibit a euhydrated state when consuming fluid ad-libitum [ 87 ]. Moreover, given the sensitivity and reliability of the human thirst sensation to denote dehydration [ 79 ], it is reasonable to suggest that drinking-to-thirst is appropriate for responding to daily hydration needs.

There are individuals with relatively high plasma osmolality thresholds for thirst [ 88 ], which can lead to chronic deviations from a euhydrated state.

Accordingly, the thirst sensation may only be appropriate in instances of acute dehydration. For the ultra-marathon runner, hydration monitoring strategies are recommended see Hydration monitoring strategies.

In addition, overuse of fluids that contain insufficient concentrations of electrolytes e. Although direct measures such as urine osmolality are rarely practical for most individuals, there are several simple and accessible tools that can be used to estimate hydration status.

The urine color chart is the most common means of estimating hydration status in runners [ 90 ]. The Venn diagram proposed by Cheuvront and Sawka [ 91 ] is a more sophisticated tool appropriate for healthy, active, low-risk populations which estimates hydration status by combining measures of nude body mass, thirst perception, and urine color.

General day-to-day hydration can, in most instances, be achieved by following a drink-to-thirst ad libitum strategy. To inform post-training rehydration strategies, athletes should measure pre- to post-exercise body mass losses, and monitor their hydration status. Given the durations typical of ultra-marathon, it is not feasible to meet caloric demands in their entirety.

Several scenarios can be examined to reinforce this hypothesis. When offset against the energy intakes observed in a typical ultra-marathon, runners are likely to exhibit a net calorie loss [ 92 ]. Accordingly, in addition to implementing an in-race nutrition strategy, an effort should be made to minimize caloric deficits before and after the race, and should be considered part of the overall holistic approach.

Indeed, CHO availability for racing can be maximized by adhering to a contemporary loading strategy i. Field studies indicate that successful completion of ultra-marathon is generally associated with greater energy and fluid intake [ 14 , 15 ], even when accounting for variations in performance time [ 15 ].

Consequently, relative to shorter races contested at a higher intensity, ultra-marathon runners can usually accommodate greater energy intake and more calorie-dense foods to the level of individual tolerance [ 94 ].

There is variability with respect to the absolute rate of energy intake reported during racing, but a sensible range can be determined. These findings have been reported elsewhere under similar race conditions [ 92 ]. Greater caloric intakes may, therefore, be necessary for longer races to enable performance.

Where GI distress is an issue, transient reductions in energy intake to the lower-end of this range are reasonable, congruent with a reduction in race pace. This may be particularly pertinent in the latter stages of a race in order to minimize the risk of hypoglycaemia which can result in race non-completion, and reinforces the importance of progressive gut training during the preparation phase [ 97 ].

The mechanistic link between glycogen depletion in skeletal muscle and liver, and a subsequent early-onset fatigue during prolonged exercise was made in the s [ 98 ]. In addition to negatively impacting endurance performance, the reduction in plasma glucose concentration that follows glycogen depletion is associated with acute cognitive decline; this, in turn, can compromise athlete safety on ultra-marathon courses of technical terrain or those requiring navigation.

Nevertheless, the absolute CHO requirements for ultra-marathon racing are unclear. There is certainly a lower rate of CHO utilization during ultra-marathon relative to marathon.

Laboratory data demonstrate that respiratory exchange ratio RER gradually decreases until the 8th hour of a 24 h treadmill run, and plateaus thereafter, reflecting a reduced rate of energy derived from CHO; moreover, this is congruent with a diminished running velocity [ 99 ].

As muscle glycogen diminishes, there is a compensatory increase in fat oxidation, with rates of 0. The prolonged durations and slower relative running speeds that characterize ultra-marathon appear, therefore, to permit increased rates of fat oxidation for adenosine triphosphate ATP re-synthesis [ ].

However, there is still a risk of glycogen depletion during ultra-marathon if work rate is too high, or if nutrition is poorly managed. Worthy of note is that extremes of both temperature and altitude will increase the absolute rate of CHO oxidation during exercise [ ], and the nutrition strategy should accommodate these variations.

With respect to the absolute amounts of CHO and fats to be consumed during ultra-marathon, individual strategies vary greatly. Over the same distance, others report greater CHO intakes of When expressed relative to body-mass, finishers consumed nearly double the amount of CHO than non-finishers 0.

Moreover, this rate of ingestion may lead to nutrient malabsorption and GI distress [ ]. With increasing race distance, a greater proportion of calories from exogenous fat may be critical for success [ 95 ]. Throughout a mile race, finishers consumed a total of Collectively, these data suggest that successful completion of ultra-marathon likely requires a higher degree of tolerance to both CHO and fat intake either as solids or fluids.

Foods with a greater fat content are advantageous during racing in terms of caloric provision per unit of weight, and this is pertinent for minimizing pack weight when running self-sufficient.

Moreover, foods with a greater fat content see Table 4 often contain more sodium, which may help mitigate the risk of exercise-associated hyponatraemia. Gastrointestinal distress and a lack of appetite in non-finishers may explain their lower overall intake.

Protein is likely an important component for prolonged endurance exercise because of the substantial proteolysis and muscle damage that can manifest before the conclusion of a race.

In controlled studies, however, there are conflicting results. By contrast, when ultra-marathon runners were supplemented with Irrespective, nutrition strategies should be implemented that mitigate the consequences of prolonged protein abstinence, and a balance of macronutrients should be consumed.

A degree of self-sufficiency when racing may provide an opportunity for runners to follow a more bespoke nutrition strategy to better satisfy individual protein needs see Table 4 for example foods. Runners who are concerned that consuming calories from protein might compromise energy availability i.

Another means by which amino acid supplementation might provide an advantage during ultra-marathon racing is in offsetting central fatigue. Prolonged exercise increases the synthesis and metabolism of 5-hydroxytryptamine 5-HT; serotonin in the brain, which is associated with lethargy, drowsiness, and reduced motivation [ ].

Critically, tryptophan the 5-HT precursor competes with BCAAs to cross the blood-brain barrier [ ], with the hypothesis that increasing the circulating concentrations of BCAAs might mitigate 5-HT accumulation, attenuate the seretonin:dopamine ratio [ ], and potentially offset central fatigue.

Indeed, athletes showed reduced effort perceptions when BCAAs were supplemented during submaximal cycle exercise performed in a glycogen-depleted state [ ]. Moreover, when trained cyclists undertook several hours of exercise in the heat to exacerbate the central component of fatigue, BCAA supplementation prolonged time to exhaustion [ ].

It is feasible that the role of BCAAs in offsetting central fatigue may be further pronounced during the extreme-distance ultra-marathons, the conditions of which are rarely replicated, and difficult to perform reliably, in a laboratory environment.

The effect of BCAAs on central fatigue is far from certain, and further studies specific to ultra-marathon running are needed to elucidate the mechanisms that might underpin any beneficial effects.

A key consideration for the ultra-marathon runner should be the palatability of food and fluid , particularly in longer races. Moreover, tastes and food preferences will likely change throughout the course of the race [ ].

In the aforementioned studies, runners tended to exhibit a penchant for savory food i. An important consideration is to what extent one must rely on food provided by organizers at pre-determined checkpoints, given that the nature of such food is unpredictable and may be in limited supply.

Accordingly, it is recommended that runners anticipate food availability, and carry their own food to more accurately fulfil their individual needs.

Finally, race organizers are encouraged to provide a variety of foods at checkpoints including a mixture of proteins, carbohydrates, and fats; see Table 4 , and to publish in advance the list of foods to be served at feed-stations, so as to aid athletes in their race preparation.

This will break the monotony associated with repetitive feed stations, and afford the runner an opportunity to mitigate caloric deficits that will likely accumulate. As race duration increases, runners tend to favor savory foods, likely reflecting energy and electrolyte insufficiencies.

Thermoregulation during exercise is largely dependent on the mammalian sweat response to evoke evaporative heat loss. Insufficient fluid replacement, therefore, results in a net loss of body water, the main consequence of which is dehydration-induced cardiovascular drift; i.

The result is a diminished exercise capacity [ ], and an increased risk of heat illness and rhabdomyolysis [ ]. Dehydration may also diminish cognitive performance [ 11 , ] and increase perceived exertion [ ]. Moreover, consideration should be given to whether hot ambient conditions are dry or wet since the latter will compromise evaporative heat loss, increase fluid requirements, and increase the risk of heat illness.

Moreover, this strategy is considered the most appropriate method of minimizing the risk of hypo- or hyper-hydration during ultra-marathon [ 16 ]. However, given that most athletes choose to consume electrolyte formulas by ingesting fluids, drinking-to-thirst may result in the under-consumption of sodium and other vital electrolytes.

In long-distance ultra-marathons, the most common hydration plan is drinking according to an individualized schedule [ ]. Moreover, finishers tend to consume fluid at a greater rate than non-finishers [ 92 ].

Collectively, the available data suggest that there are broad individual intakes among ultra-marathon runners, but that successful runners tend to meet the lower-limits of recommended values.

Fluid ingestion that results in diluted plasma sodium may be indicative that runners are not meeting their sodium needs [ 92 ]. Over-hydration, and the consequent dilution of plasma sodium, can have severe adverse effects on health see Exercise-associated hyponatraemia , and there are case-reports of water intoxication in runners who aggressively rehydrate [ ].

Individuals wishing to optimize performance should determine their individual sweat rates, in advance, under conditions which resemble competition i.

An accessible means of estimating sweat rate is to measure nude body mass pre- and post-exercise; this will allow for an individualized fluid ingestion strategy. Sodium is the major ion of the extracellular fluid and contributes to the generation of action potentials for muscle contraction, but it also has an important role in fluid retention [ ].

Modest symptoms include headache, fatigue, and nausea, but can result in seizures and death in severe cases [ 9 ]. Two key, interrelated mechanisms are responsible for hyponatraemia: i excessive sodium loss from the extracellular fluid resulting from a high sweat rate e.

Although the condition is rare, and individual susceptibility plays a role in prevalence, the earliest reported cases were observed in ultra-marathon runners and Ironman triathletes [ 9 ] i.

Slightly greater amounts of sodium and other electrolytes will be required in hot e. Indeed, there is anecdotal evidence that effervescent dissolvable electrolyte tablets, and liquid electrolytes added to water, can compromise drink palatability, particularly during long races or those contested in the heat, thereby resulting in reduced fluid consumption.

As such, capsules or tablets that can be swallowed whole are recommended, thus leaving water untreated. The amounts taken should also be offset against the sodium consumed from salt-containing foods, although it should be noted that it is unlikely that the recommended rate of sodium intake will be achieved from foods alone.

In addition, the concentrations of some electrolytes e. As such, runners are encouraged to pay close attention to the ingestion method and composition of their electrolyte formula. Given the inherent risks associated with EAH, greater care should be taken to educate ultra-marathon runners on its deleterious consequences.

For example, there are data to suggest that although sodium ingestion may help attenuate the likelihood of developing EAH, sodium intake is not sufficient for this purpose when simultaneous with excessive fluid ingestion [ 89 ].

As a result, runners sometimes adopt a low-volume drinking plan instead of increasing sodium intake congruent with their needs [ ].

Such poor practice must be challenged, since it is possible to consume adequate amounts of both fluid and sodium during prolonged exercise, with sufficient practice. The type, duration, and severity of symptoms vary on an individual basis, with upper GI-tract related issues e.

The pathophysiology of GI distress during ultra-marathon training and racing is multifactorial, but is likely the result of reduced mesenteric blood flow [ , ], leading to relative GI hypoperfusion [ ].

An increased appearance of systemic lipopolysaccharides LPS from gram-negative intestinal bacteria may result from acute intestinal tight-junction protein disruption, thereby provoking an immune response, as well as endotoxin-mediated GI distress [ ].

Symptoms pertaining to exercise-associated GI distress are highly individualized and may be related to predisposition, intestinal microbiome activity based on bacterial quantity and species diversity , and feeding tolerance [ ].

The primary nutritional cause of GI upset during ultra-marathon is the high intake of CHO, particularly hyperosmolar solutions e. Runners experiencing upper-GI discomfort were reported to have a greater energy and CHO intake than runners not experiencing symptoms [ ].

This supports the notion that high rates of CHO ingestion, although being beneficial for race completion, might actually exacerbate symptoms of GI distress.

In addition, strategies that could mitigate the likelihood of LPS release into the blood and, thus, endotoxin-associated symptoms, include limiting the consumption of saturated fat [ ], avoiding the consumption of non-steroidal anti-inflammatory drugs NSAIDs [ ], and maintaining an adequate water intake [ ].

Recognizing the early onset of GI distress, and strategizing to maintain energy intake close to target values regardless, may be the key to managing some GI-related issues. Although counterintuitive, there may be some instances when eating regardless of nausea will give the most relief from such symptoms, especially when nausea is caused by hypoglycemia.

While ultra-marathon training may elicit progressive behavioral changes e. It is apparent that well-trained athletes can tolerate higher intakes of CHO during running [ ], and that habituation to a high CHO diet enhances total carbohydrate oxidation rates which may be important for sustained race performance [ ] and reduced GI upset.

Where symptoms of irritable bowel syndrome IBS are present, practicing a low FODMAP fermentable oligosaccharide, disaccharide, monosaccharide and polyol diet has been shown to reduce GI distress acutely [ , ]. While responses to low FODMAP diets may be highly individual, strategic implementation under guidance of a qualified nutrition professional in the days preceding a race, or during training when acute symptoms occur, may confer GI support.

Nevertheless, further research is warranted to confirm whether such benefits are applicable during sustained running. Finally, the use of probiotic bacteria, particularly including the gram-positive genera Lactobacillus and Bifidobacterium species, has been shown to modify GI microbiota [ ] and may provide an adjunct nutritional strategy in cases pertaining to acute GI disruption e.

There is evidence of reduced GI symptom prevalence and severity following the administration of probiotics [ , ] although benefits may be individualized and strain-specific.

Lactis CUL34 was shown to reduce GI symptoms, and may be associated with the maintenance of running speed in the latter stages of marathon [ ]. The inclusion of dietary prebiotic nutrients e. Symptoms of upper-GI distress, particularly nausea, are commonly reported during ultra-marathons, are a cause of non-completion, and are more prevalent in longer races.

To mitigate GI distress, runners should avoid highly concentrated CHO, and minimize dehydration. Nutritional strategies should be practiced in training, well in advance of racing, to allow sufficient time for GI adaptations that optimize CHO absorption, and mitigate GI distress.

Caffeine is widely consumed as part of a normal diet, and there is clear evidence-for-efficacy regarding its ergogenic properties in a variety of sports [ , , ], although the extent of the ergogenic effect is largely dependent on inter-individual genetic variance [ ].

Caffeine works via two potential mechanisms: firstly, there is a centrally-mediated ergogenic effect, whereby caffeine blocks adenosine receptors in the brain and inhibits the binding of adenosine, resulting in improved cognitive function and concentration; secondly, caffeine potentiates intramuscular calcium release, thereby facilitating excitation-contraction coupling to increase muscle contractile function for review, see [ ].

Caffeine can cause a number of side effects, however, including GI distress, headaches, and anxiety [ ]. Caffeine strategies should, therefore, be carefully planned and practiced in advance of competition.

It should be noted that while there is some evidence that reducing habitual intake prior to competition might enhance caffeine sensitivity on race day [ ], the hypothesis has been contested [ ]. Caffeine has been shown to positively impact endurance performance [ ], but there is a paucity of data on the use of caffeine during ultra-marathon.

However, the dose response is not linear i. A conservative strategy may also mitigate the likelihood of side-effects. If frequent doses are to be taken during ultra-marathon, then lower more sustainable amounts e.

Importantly, caffeine has been shown to be effective when taken in the latter stages of endurance exercise [ ]; accordingly, ultra-marathon runners are encouraged to target any caffeine intake for the latter stages of competition.

Individual sensitivity should, of course, be carefully considered, and strategies well-rehearsed. tablets vs. Although enhanced fat oxidation may be facilitated by nutritional ketosis evoked via caloric restriction, carbohydrate restriction, or chronic high-fat diets , current evidence does not indicate an ergogenic effect when compared to diets that have a moderate-to-high CHO content.

For example, exogenous fatty-acid supplementation e. Animal models indicate a potential mechanistic benefit for the inclusion of MCTs to enhance mitochondrial biogenesis through both Akt and AMPK signalling, thereby enhancing endurance performance [ ]. Nevertheless, controlled studies show limited impact of MCTs on fuel utilization during exercise when human subjects are in a low-glycogen or a glycogen-replenished state [ ].

A further consideration is that, in order to mitigate the likelihood of GI distress during exercise, MCT oil should only be taken in relatively small amounts i. Nevertheless, there are anecdotal reports of MCT use by ultra-marathon runners, during both training and racing, which warrant further study.

Performance benefits have, however, been repeatedly refuted [ , ]; as such, despite the compelling mechanistic basis for ketone esters to facilitate ultra-marathon performance, there is currently no direct evidence to this effect, and further research is needed.

Athletes should ensure that normal dietary intake is sufficient to provide an appropriate variety and quantity of micronutrients.

Given the substantial oxidative stress associated with ultra-marathon competition, isolated vitamin C has been hypothesized as a means of attenuating the high prevalence of post-race immunosuppression, although the data are conflicting.

By contrast, a randomized, placebo-controlled trial by Peters et al. Accordingly, acute supplementation in the immediate pre- or post-race period may mitigate oxidative damage and immunosuppression that precedes URTI, although further research is needed to corroborate these findings and establish the effects of acute, in-task supplementation.

Chronic, daily supplementation with antioxidants is not recommended due to the potential blunting effect on several aspects of exercise-induced physiological adaptation for review, see [ ]. L-glutamine is the most abundant amino acid in the body, with an essential role in lymphocyte proliferation and cytokine production [ ].

In catabolic and hypercatabolic situations, L-glutamine can be essential to help maintain normal metabolic function and is, therefore, included in clinical nutritional supplementation protocols and recommended for immune-suppressed individuals [ ].

Nevertheless, in terms of mitigating immunodepression after exercise, the available evidence is not sufficiently strong for L-glutamine supplements to be recommended for athletes for review, see [ ]. By contrast, there is emerging research that, in addition to probiotic use, L-glutamine may provide adjunct nutritional support for GI epithelial integrity [ ].

Furthermore, the authors highlighted a potential dose response, with higher concentrations 0. It has been proposed elsewhere that L-glutamine supplementation may be associated with heat-shock factor-1 HSF-1 expression, providing a mechanistic link to GI integrity via regulation of occludin tight-junction proteins [ ].

Further research is warranted with respect to L-glutamine supplementation in the context of ultra-marathon. To mitigate the extreme peripheral stress associated with competition, ultra-marathon runners commonly use analgesics including NSAIDs Ibuprofen or aspirin , non-opioid analgesics paracetamol , and compound analgesics co-codamol [ ].

There are several reports of attenuated exercise-induced muscle inflammation, circulating creatine kinase levels, and muscle soreness when NSAIDs were administered prophylactically before exercise [ , ].

By contrast, a number of studies have found no effect of NSAIDs on analgesia or inflammation during exercise [ , , , , ]. Notwithstanding, NSAID use can cause serious adverse effects on cardiovascular, musculoskeletal, gastrointestinal, and renal systems, all of which might be exacerbated by ultra-marathon running for review, see [ ].

There is an increased risk of GI-injury with NSAID use, and this may be exacerbated in long-distance runners contesting marathon and ultra-marathon who already exhibit a greater incidence of GI-bleeding [ , , ]. Frequent prophylactic use of NSAIDs is also associated with increased risk of renal side-effects [ , ], and concern has been expressed about a possible causative role of NSAIDs on exercise-induced hyponatremia [ ].

Given the equivocal evidence-for-efficacy and the acute contraindications, NSAID use during ultra-marathon is strongly discouraged. We thereby recommend race organizers to discourage NSAID use among their participants. Non-NSAID analgesics e. Caution is urged, therefore, against the frivolous and systematic use of analgesics for symptom-masking.

Accordingly, there is a growing need for greater batch-testing of supplements, and special consideration should be given when athletes are entering races that are overseen by anti-doping organizations. This will be critical in minimizing the risk of inadvertent positive tests.

Despite the potential efficacy of other ergogenic aids e. Runners should abstain from NSAIDs e. Analgesics may provide effective pain-relief, but conservative use is advised in order to avoid the inadvertent masking of serious symptoms.

Ultra-marathon is a rapidly-growing sport contested by amateur and elite athletes the world-over. Due to its dynamic and complex nature, runners must endure myriad physiological stresses which can substantially impinge on both health and performance.

This Position Stand highlights the nutritional considerations that are important for facilitating training adaptation, improving race performance, and mitigating the negative consequences of participation.

These recommendations, as outlined in our evidence statements, should be considered by athletes and coaches, and may inform best-practice of those overseeing ultra-marathon events i. Millet GP, Millet GY.

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Most runs within a given week fall into this category. They are shorter than 90 minutes and are done at an easy pace. Yet, many runners fail in their training by running these too fast. Easy runs can certainly take place on trails, but climbs may elevate your heart rate.

This is okay in short, infrequent bouts, but use hiking breaks on elongated and steep pitches to keep the effort easy. Recovery runs assist with the recuperation process between tough efforts. They can be used for the rest periods between taxing intervals or on the days following rigorous workouts, including a long run.

They are purposely short in duration and kept at a very slow pace. Again, if you find yourself on hilly terrain, keep these efforts easy by incorporating hiking breaks or stopping temporarily to catch your breath. The long run is the most crucial of the three endurance-based workouts for ultrarunners.

It enables you to build a strong fitness base, run farther than previously possible, and, in turn, boosts race-day confidence. This is what usually comes to mind when thinking about running long.

The objective is simply to spend a lot of time on your feet in order to:. The pace should be easy, but the effort consistent. I recommend you do this workout first thing in the morning, because only water coffee or tea without sugar or creamer is also allowed and electrolytes are permitted until the run is complete.

This technique teaches the body to use fuel stores more sparingly and perform more efficiently on low blood sugar. These runs are very taxing on the body and spirit, and should therefore be limited to training runs that are three hours or less and placed three or four weeks apart.

Their use is practical in early season training when weekly intensity levels are low. These workouts are the exception to the typical long-run theory that time on feet is all that matters.

They are the most challenging component of our endurance-based training. Just as the name implies, the goal is to finish fast or with a high level of perceived effort. These runs make you a stronger runner, build your confidence, and become race-day habit-forming.

Due to the amount of energy expended on the back end, fast-finish sessions are slightly shorter than the standard long run. There is no reason for this because sorry-not-sorry Leadville is not that hard.

Many blame the altitude. Others blame their fitness. Some blame the lack of qualifying standards to get in. After observing literally hundreds of athletes choosing to drop out, I have come to the conclusion that altitude, fitness or experience of the athlete is not to blame.

Inspiration will take you farther than calories, your VO2max, your pacer or your new pair of shoes. The trick is, you have to find what inspires you. You have to have something you are emotionally connected to and invested in.

That can be the sensation of the finish, the challenge, or being a role model to your kids. Whatever is it is, it should resonate on a deep, personal and emotional level… not a rational one. Early in my coaching career, I always said I wanted my athletes to rest more. Rest is good, but it was naive of me to think that more is always better.

What I have learned is that athletes have the time to rest. What does this mean? Turn off your phone and meditate for 15 minutes instead of checking Twitter and mindlessly scrolling through Instagram. If you have a recovery run planned, do it as slowly as possible. Instead of watching TV, do some self bodywork with a foam roller or massage ball.

None of these activities cost one single minute more to do. But, they will all have positive impacts on your recovery. All my athletes have goals. It is a necessary carrot and part of what will make them great. However, for every goal they have stated, there are multiple pieces of process underneath that supports that goal.

It is not a sustainable nor effective way to manage training. Athletes are best served to focus primarily on the processes they can control day in and day out. If you are deliberate in your efforts and take joy in the process, the outcome normally takes care of itself.

So there you have them. All without a single additional workout, supplement, interval or gadget. This is a really great article. The hike to run ratio is a new one for me. Will be trying this for sure. Great work and thanks!!! I come back and read this article every so often to remind myself of all these great points, especially with regards to rate of perceived exertion RPE rather than paying attention to pace or HR.

Thanks Koop! Yes, two six mile runs can be completely different. So, miles alone is not indicative of training load. I can do an easy recovery jog for an hour doing 6 ten-minute miles on the road; or a harder 6 ten-minute miles on technical trail; or I can do a hard tempo run and hit near 10 miles in an hour; or I can warm up for 20 min and do leg and lung crushing hills or intervals for the remaining 40 min.

Excellent article. Have taken good notes, Thanks! Finally, creatine may also help reduce the risk of injury by increasing muscle tissue strength and resilience. Creatine is an amino acid that is naturally produced by the body but can also be supplemented.

For ultra runners, creatine has several benefits, including increased energy levels. Creatine helps muscles produce ATP, which provides them with energy for intense activities such as long-distance running.

Studies have shown that supplementing with creatine can improve energy levels during endurance exercise, allowing runners to push themselves further and longer. Additionally, it has been suggested that creatine can reduce fatigue and muscle soreness in runners.

To reap the benefits of creatine supplementation, it is recommended to take it before or during exercise. Ultra runners should consider incorporating creatine into their supplement regimen before their next long run to experience increased energy levels and reduced muscle fatigue.

Creatine is a naturally occurring compound found in the body and can also be consumed through dietary sources or supplements. For ultra runners, creatine has several benefits including enhanced muscle recovery.

It has been shown to improve performance, reduce fatigue, and help athletes maintain energy levels during longer runs and races. In addition, creatine can increase strength and power output, which are important for ultra runners. Lastly, it can reduce the risk of injury by helping to protect muscles from damage caused by intense exercise.

As such, supplementing with creatine may be a worthwhile consideration for runners looking to enhance their performance and overall health.

For ultra runners, creatine can provide a range of benefits to help improve endurance and performance. This means that runners who supplement with creatine may be able to run faster and longer without feeling as fatigued. In addition, creatine has also been shown to improve mental clarity and focus.

This is important for runners who need to stay alert and focused during long or intense runs. By improving mental cognition, creatine can help runners maintain their pace and avoid distractions that might otherwise slow them down.

Other benefits of creatine supplementation include increased muscle strength and improved recovery time between workouts. These benefits make creatine an effective supplement for ultra runners who are looking to improve their performance and achieve their goals.

Creatine is a supplement that is beneficial for ultra runners. It can help increase muscle mass and strength, which in turn leads to better performance. Additionally, creatine helps the body produce more energy, allowing runners to go farther and faster.

It also helps reduce fatigue and muscle soreness during recovery. Moreover, one of the benefits of creatine for ultra runners is that it can boost the immune system, reducing the risk of illness and injury.

Research suggests that creatine supplementation can strengthen the immune system by increasing white blood cell count and function.

However, as with any supplement, it is important to consult with a healthcare professional before use. For ultra runners, supplementing with creatine can offer several benefits to improve performance.

For most, this is achieved at nearly 12k to half-marathon race pace. I started feeling more comfortable again for this training block. I hope that continues. It just transfers to your efficiency in running on everything.

Jim Walmsley on the way to his mile world record in Photo: Hoka. If you find the length of tempo runs tough to recover from or just too daunting, try tempo intervals as a way to increase your stamina. Though these are slightly faster than tempo runs, they are broken into two or more repeats with short 2- to 5-minute recovery jogs in between.

Tempo intervals should be run at to minute race pace or appropriately 10k to 15k race pace. Each repeat should last between 6 and 15 minutes. The longer repeats necessitate a longer recovery interval.

Start with short repeats and increase their length as your fitness and confidence develop. Thirds progression runs are an exception to the rules. No warmup is required as this workout begins at a comfortable, conversational pace; however, as the workout progresses, you pass from an endurance-based training zone into a stamina-based training zone.

As the name implies, the workout is split into thirds. For the first third, run at a very slow, easy pace. In the second third, increase your pace to a manageable, but steady speed.

This is an excellent workout for developing a sense of pace and effort as you pass from one training zone to the next. Like the recovery, easy, and long runs described in our endurance-based workouts article , stamina-based workouts can also be performed too aggressively.

Learn how pace and perceived effort correlate by running them on flat, even surfaces. As you discover how these particular sessions should feel, take them to more difficult terrain, like the trails and rolling roads where you will need to rely on your honed sense of effort rather than splits on a watch.

Anna Mae Flynn at the Lake Sonoma 50 Mile. Ian Torrence has more than 12 years of experience coaching runners of all levels. Ian and his wife, Emily, are online coaches at Sundog Running. Information about his coaching services can be found at SundogRunning. Columns , Resources , Your Ultra-Training Bag of Tricks.

By Ian Torrence on December 6, Comments. Support us! His training system for marathoners revolves around increasing that power so that output at lactate threshold and aerobic threshold get very close together. In addition, these runs could improve the power and recruitment of Type-I slow-twitch muscle fibers, while also spurring the production of mitochondria and capillaries.

And since the runs are faster, the muscular output is greater, leading to more strength. But there are downsides too.

Go too hard, and some of those aerobic benefits erode away, while endocrine and nervous system stresses go sky-high. A steady run forced on tired legs leads to injury risk, with little benefit other than mental toughness.

The goal is to run with as much pace as possible with as little effort as possible, since that is when running economy improves the most. Steady runs are especially important for marathoners, who often use long runs to lock into faster paces.

The trail athletes face a much wider range of musculoskeletal and biomechanical stresses, emphasizing the ATHLETE part of being a runner. We like athletes to apply five rules to add some structure to these unstructured effort days. Let the body kick into a fully aerobic gear. No pace is too slow, like all easy runs.

After those 10 minutes, listen to your body. What is it saying? As you adapt to the musculoskeletal demands, downhills will become free speed.

On flatter terrain, embody smoothness with relaxed arms and no urgency. If you walk most of the ups in training, try to run a bit more.

If you walk some of the ups, try to run all but the steepest grades. If you rarely walk, add a bit more power into your stride. RELATED: When and Why to Train Below Aerobic Threshold.

Fueling is key to improve endurance and adapt to the training you are doing, while also mitigating some of that risk. Sometimes, they will even include minute moderately hard tempo runs after a warm-up, which is how we can spur more long-distance adaptations without doing 30 or 40 mile runs in training.

Every weeks, a mid-week trail run may be a similar approach, often in aerobic build weeks. David Roche partners with runners of all abilities through his coaching service, Some Work, All Play.

Pushing yourself to go longer at a given pace rather than faster is the key component. In general, LT is attained near a one-hour race pace and stamina-based training focuses on working at or near this point.

Running too fast will only tire you and shorten the amount of time you are able to hold your effort within this beneficial range. Unlike your endurance-based workouts , stamina-based workouts require to minute warmup and cooldown periods.

Twenty minutes at a steady state pace will provide training benefits early in the training cycle, but as your fitness improves, work up to an hour or more.

The tempo run is probably the most misinterpreted workout in the running community. Tempo runs are more intense and thus shorter in duration than steady state runs. They last between 15 and 40 minutes and are performed at LT, which is between a to minute race pace.

For most, this is achieved at nearly 12k to half-marathon race pace. I started feeling more comfortable again for this training block. I hope that continues. It just transfers to your efficiency in running on everything.

Jim Walmsley on the way to his mile world record in Photo: Hoka. If you find the length of tempo runs tough to recover from or just too daunting, try tempo intervals as a way to increase your stamina.

Though these are slightly faster than tempo runs, they are broken into two or more repeats with short 2- to 5-minute recovery jogs in between. Tempo intervals should be run at to minute race pace or appropriately 10k to 15k race pace.

Each repeat should last between 6 and 15 minutes. The longer repeats necessitate a longer recovery interval. Start with short repeats and increase their length as your fitness and confidence develop. Thirds progression runs are an exception to the rules. No warmup is required as this workout begins at a comfortable, conversational pace; however, as the workout progresses, you pass from an endurance-based training zone into a stamina-based training zone.

As the name implies, the workout is split into thirds. For the first third, run at a very slow, easy pace. In the second third, increase your pace to a manageable, but steady speed. This is an excellent workout for developing a sense of pace and effort as you pass from one training zone to the next.

Like the recovery, easy, and long runs described in our endurance-based workouts article , stamina-based workouts can also be performed too aggressively. Learn how pace and perceived effort correlate by running them on flat, even surfaces.

Faster easy running often coincides with faster racing, leading to an association that can undercut growth after the aerobic, endocrine and nervous systems rebel against the chronic stress. Or in athletes that start their running journey later in life, any run might be moderate at first, creating an understanding that all running should be moderate even as fitness grows.

In fact, I am going on the record to say I am against throwing out babies or bathwater altogether. I am brave to take that stand, thank you for saying so. That is why doing moderate running all the time can be so negative—if an athlete feels like crap and forces the pace, it becomes a hard run that can tear them down.

RELATED: Aerobic Build Weeks. Heart rate may be below aerobic threshold on downhills and flats, and closer to lactate threshold on climbs. RELATED: Forget Everything You Think You Know About Form. Coach Renato Canova works with many of the best marathoners of all time, and these types of steady effort long runs are key to his system.

In his book Marathon Training: A Scientific Approach , Canova refers to steady effort runs as being around what he calls aerobic lipidic power, essentially meaning the effort is both fast and sustainable.

His training system for marathoners revolves around increasing that power so that output at lactate threshold and aerobic threshold get very close together. In addition, these runs could improve the power and recruitment of Type-I slow-twitch muscle fibers, while also spurring the production of mitochondria and capillaries.

And since the runs are faster, the muscular output is greater, leading to more strength. But there are downsides too. Go too hard, and some of those aerobic benefits erode away, while endocrine and nervous system stresses go sky-high. A steady run forced on tired legs leads to injury risk, with little benefit other than mental toughness.

The goal is to run with as much pace as possible with as little effort as possible, since that is when running economy improves the most.

Steady runs are especially important for marathoners, who often use long runs to lock into faster paces. The trail athletes face a much wider range of musculoskeletal and biomechanical stresses, emphasizing the ATHLETE part of being a runner.

We like athletes to apply five rules to add some structure to these unstructured effort days. Let the body kick into a fully aerobic gear. No pace is too slow, like all easy runs. After those 10 minutes, listen to your body. What is it saying?