Fueling for Energy, Endurance, and Recovery

Food significantly impacts how we feel and perform during exercise and recover afterward. Carbohydrates and fats act as the body’s primary energy sources during exercise while protein is required for muscle growth, repair, and maintenance. During a workout, your body will use a mix of carbs and fat for energy, but depending on the type, intensity, and duration of the workout, the body will rely on one more than the other. For example, during longer low-intensity workouts, such as walking and distance running or cycling, the body will burn a higher percentage of fats for fuel. In contrast, during short sessions of high-intensity workouts, such as sprinting, interval training like HIIT, and heavy weightlifting, the body will still use fats, but requires more carbohydrates for a quick source of energy. The overall goal, though, is to become metabolically flexible, which will allow your body to efficiently switch between carb burning and fat burning as needed; this will enhance energy levels and performance, as well as overall health. Support metabolic flexibility by exercising regularly and focusing on whole, nutrient-dense foods including vegetables and fruits, quality protein, and healthy fats, while avoiding processed foods, sugar, refined grains, and vegetable oils such as corn, cottonseed, and soy oils.¹

To fuel your workout, forget the giant bowl of pasta to carb load. Instead, eat complex carbohydrates like whole grains and vegetables 24 to 36 hours prior to working out; fast-digesting carbs like fruit or beetroot juice can be consumed 30 to 60 minutes before exercise for “quick” energy. It’s also important to prioritize protein, as it provides the building blocks to build and repair muscle tissue and is absolutely required to increase muscle mass. A 2022 meta-analysis of 82 studies published in the journal Sports Medicine concluded that 1.5 grams per kilogram of body weight may be the “most appropriate amount of total protein intake for maintaining and augmenting muscle strength along with resistance training.”²  For a 150-pound person, that would be about 102 grams of protein daily; however, those requirements may change depending on age (e.g., older adults require more protein) and level of exercise intensity and frequency.

Foundational Support for All Athletes

EPA and DHA

These two omega-3 fatty acids, found in cold-water fatty fish and fish oil are well recognized for their ability to modulate inflammation throughout the body, including the muscles, helping speed recovery and slowing muscle breakdown. Researchers found that 3 grams of fish oil daily (supplying a total of 1.3 grams of EPA and DHA combined) decreased oxidative stress markers in exercising muscles and reduced pain associated with muscle damage.³ EPA and DHA intake have been shown to support a healthy metabolism, the development of lean muscle mass, and improve the muscles’ ability to burn fat for fuel.⁴ To learn more about the many additional benefits of EPA and DHA, check out the article EPA & DHA: The Fats of Life.

Glutamine

Glutamine is the most abundant amino acid in skeletal muscle. It provides an anti-catabolic (anti-breakdown) effect and supports protein synthesis. When taken after exercise, glutamine can help lower muscle breakdown, likely by decreasing post-training cortisol levels. One small study found that oral glutamine supplementation lead to faster recovery and diminished muscle soreness.⁵ Glutamine also plays an important role in immune function and may support athletes’ immunity after heavy training loads.^{6 7}

Probiotics

These beneficial bacteria that can reside in our intestines are capable of supporting athletes through some of the unique immune challenges they face. For instance, while moderate exercise can boost immunity, elite athletes may actually be at greater risk of contracting colds and flus. Once sick, athletes cannot train as hard as they would like and may not get as much out of their training. Training while sick may also impede the full healing process, making one more prone to colds and flus and creating a vicious cycle. In one small study, elite distance runners given probiotics for four months experienced fewer respiratory symptoms and less severity of illness than elite runners given the placebo.⁸ Regular supplementation with probiotics also may help to protect from “leaky gut,” the intestinal permeability that often comes with regular intense and exhaustive exercise.^{9 10} Beyond protection, probiotics may even enhance muscle mass and endurance and improve recovery.^{11 12 13}

Vitamin D

Vitamin D receptor sites are widespread in muscle tissue, which hints at this nutrient’s importance in muscle health. Vitamin D deficiency is common among athletes and non-athletes alike. In the elderly, lower vitamin D levels are associated with decreased musculoskeletal performance and increased falls and injuries. In athletes, correcting a vitamin D deficiency has been shown to improve exercise performance as well as muscle mitochondrial function, which may help to inhibit muscle fatigue.^{14 15} For more information on vitamin D, check out the articles on Vitamin D and Vitamin D—Testing and Dosing.

Supplements for Muscle Health

Branched Chain Amino Acids (BCAAs)

The essential amino acids leucine, isoleucine and valine make up the BCAAs. These amino acids make up the largest percentage of the body’s essential amino acid pool and are present in high levels in the muscles.¹⁶ BCAAs are directly involved in stimulating the pathways responsible for muscle protein synthesis and can be directly metabolized into skeletal muscle.  Leucine is of particular importance, since it appears to be the driving force behind many of the benefits associated with the BCAAs. Leucine is, however, more effective in the presence of other amino acids, which makes supplementing with additional protein (such as whey) or the complete family of BCAAs a good idea. In one study, 85mg of BCAAs/kg of body weight supplemented before, during, and after a resistance training workout led to a 30-fold increase in muscle-protein building compounds one hour after a workout compared to placebo.¹⁷ Studies using leucine alone have found 2.5 to 10 grams a day to show benefit.^{18 19 20}

HMB (a.k.a. beta-hydroxy-beta-methylbutyrate)

HMB is a metabolite produced in the body from the breakdown of leucine and derived in small amounts from some foods such as catfish, grapefruit, and breast milk. It decreases protein loss during stress by inhibiting protein breakdown. Athletes use HMB supplements because they help the body retain nitrogen (a major component of amino acids, the building blocks of protein) which helps to slow muscle damage and inhibit muscle breakdown during intense exercise. In one study, volunteers supplemented with HMB experienced less protein breakdown during the first couple weeks of a new resistance training program and overall were able to lift more total weight and increase strength better than the placebo group.²¹

TMG (Trimethylglycine)

This natural compound, also called betaine or betaine anhydrous, helps your muscles function at their best, in part by acting as an osmolyte, a molecule that helps cells—including muscle cells—stay hydrated, maintaining optimal fluid balance, reducing muscle fatigue, and increasing endurance. Studies have found that men taking 1.25 grams of betaine once or twice a day for two weeks experienced improved endurance, quality, and power of both upper and lower body exercises.^{22 23} Another study found that untrained women taking 2.5 grams of betaine daily for eight weeks in conjunction with a resistance training program, improved body composition by enhancing reductions in fat mass.²⁴ Betaine can be taken pre-workout to help muscle stay “pre-hydrated” and/or post-workout to rehydrate muscle cells.

ZMA

This combination of zinc, magnesium aspartate and B-6 was shown to improve muscle strength in athletes after 7 weeks of supplementation when compared with placebo. ZMA’s effects are likely due to its ability to raise low blood concentrations of zinc and magnesium, which are associated with low levels of testosterone and growth hormone and can impair fitness performance. When paired with resistance training, ZMA may improve muscle strength. To support muscle repair and development, it is best to take ZMA before bed.²⁵

Supplements to Support Endurance

Beetroot

Beetroot is one of the best dietary sources of nitrate and nitrite, which are metabolized by the body into nitric oxide. Nitric oxide signals the blood vessels to relax, thus enhancing blood flow. Far from simply enhancing blood flow, though, nitric oxide also appears to have positive effects on exercise performance. One way in which this happens is by reducing the cost of physical exercise on muscles, making what oxygen is present be used more efficiently, delaying onset of fatigue.²⁶ In human studies, beetroot (usually taken as juice) increased the total power output and time trial performance in cyclists, improved perceived exertion and running speed in recreationally fit adults, improved total repetition time in rowers, and increased breath-holding time in divers.^{27 28} Nitrate and nitrite derived from beetroot appear to be most beneficial for high-intensity, constant work-rate exercise.²⁷ To enhance exercise performance, beetroot can be taken daily or acutely 1-3 hours before exercise. Beetroot is, of course, available fresh, but it is also available in juice form and in powdered supplements for greater convenience.

Beta-Alanine

During high-intensity exercise, acid is produced as a byproduct of the process of making the energy necessary for muscle contractions. Although the acidity is associated with muscle building hormone stimulation, the burn of high acid levels can force you to stop your workout prematurely. Beta-alanine supports the body’s acid buffering capacity and helps us better tolerate performance-related acidity in the blood, thus improving power and strength, and delaying fatigue during high-intensity workouts.^{29 30}

Supplements to Support Recovery

Adaptogens

Herbs that improve the body’s resistance to a variety of stressors (physical, psychological or chemical) and help bring the body into balance are considered adaptogens. This class of herbs may be of particular value to athletes in improving physical fitness and performance and in supporting a healthy stress response and overall vitality. Good choices include one or a combination of the following:

• Ashwaganda – Supports healthy stress hormone levels, modulates inflammation, improves VO2 max, improves muscle strength and supports muscle recovery.^{31 32 33 34 35} It has been traditionally used to promote general strength and vitality.
• Rhodiola rosea – May improve endurance exercise capacity and protect against fatigue caused by exercise.^{36 37 38} It may be of special value for those adjusting to high-altitude training, especially when combined with cordyceps.³⁹
• Cordyceps – Although technically mushrooms, not an herb, cordyceps has been traditionally used to enhance endurance, energy, and vitality. In animal studies, cordyceps has been found to increase time to exhaustion during exercise, improve endurance capacity and enhance exercise performance.^{40 41 42 43} In a small human study, cordyceps was combined with Reishi, another medicinal mushroom, daily for three months, as amateur cyclists trained for and participated in major cycling races. Those who took the supplements were found to be better protected from overtraining syndrome and also to have increased protections against free radicals.⁴⁴
• Ginseng – Long valued in traditional medicine to support physical and mental energy, ginsengs may also specifically support exercise performance. A 2023 review in the journal Nutrients examining ginseng’s effect on exercise-induced muscle damage, found positive results for physiological markers of muscle damage. The researchers also found evidence that ginseng reduces fatigue and supports muscle regeneration, exercise performance, and injury prevention. The studies used various types of ginseng, including American ginseng, Korean ginseng, and red ginseng with doses ranging from 420 mg to 2 g per day. Benefits were seen in participants taking ginseng for at least seven days and up to eight weeks.⁴⁵

Electrolytes

Electrolytes are charged molecules found inside and outside the cells of the body. They are responsible for maintaining a healthy fluid balance and are essential for nerve impulses and muscle contractions. In general, electrolyte replacement is not necessary for those undertaking short bouts of exercise, especially if sweating is minimal. However, for those who participate in endurance sports or who perspire very heavily during workouts, adding electrolytes to your water can help to replace those that are lost, protecting from the dangerous condition of hyponatremia, whose symptoms can range from mild headache and nausea to seizure, coma and even death. The most important electrolytes to replace are sodium, potassium and chloride. Adding carbohydrates to a liquid electrolyte solution improves the absorption of electrolytes (particularly sodium) from the small intestine.⁴⁶

Phosphatidylserine

Commonly referred to as PS, phosphatidylserine is a unique type of phospholipid that is found in the membrane of every cell. PS supports concentration and focus, and in one study, golfers who took 200mg a day for 6 weeks had an improved number of ball flights during tee-off.⁴⁷ PS is also well recognized for its ability to modulate the stress response. Exercise is a moderate stressor and causes the release of cortisol, one of our stress hormones that plays many important roles in the body but can wreak havoc when over-secreted. Excessive exercise (a.k.a. overtraining) or exercise coupled with other stressors results in an inability to recover from exercise due to chronically elevated cortisol levels. PS helps to modulate the cortisol response to exercise and helps to offset the effects of high cortisol.^{48 49 50}  One study even found that PS significantly reduced muscle soreness and improved perceptions of well-being during periods of intense weight training.⁵¹

Turmeric

This golden spice associated with Indian cuisine contains the compound curcumin, which has been catapulted into the spotlight due to its inflammation modulating effects. When added to a workout routine, curcumin reduces muscle soreness and supports recovery.⁵¹ It also reduces the rate of muscle breakdown in old and young athletes alike, preserving strength and supporting athletic performance.⁵²

Whey Protein

Protein is an essential nutrient for human health and one that is especially important for athletes. Protein is necessary for building and repairing muscles and tissues, making immune complexes that keep us healthy, making hemoglobin to carry oxygen around the body, and making hormones and enzymes. Many quality foods can contribute to an athlete’s protein needs, but whey protein might be an especially good addition. Whey protein is derived from dairy and is one of the most absorbable and usable forms of protein.⁵⁴ It is an excellent source of branch chain amino acids (BCAAs) and in particular leucine, an amino acid that directly activates muscle protein synthesis. It is a good source of the sulfur-containing amino acids cysteine and methionine, which are precursors to glutathione, one of the body’s most potent antioxidants.⁵⁵ Whey can also be a good source of immune complexes, such as lactoferrin, which support healthy immune function in over- and intensely-trained athletes.⁵⁴ Supplementing the diet with whey protein in close proximity to exercise (before, during, or after) may help to increase lean tissue mass, improve exercise performance, and enhance recovery from heavy exercise by decreasing muscle damage and soreness.^{56 57 58}

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