Shawn Talbott highlights seven supplements with proven benefits for endurance athletes.
Written by: Shawn Talbott, PhD
As an endurance athlete, you might be interested in dietary supplements that have proven benefits to enhance oxygen efficiency, improve blood flow, balance hormone profile, and improve stress adaptation.
The Magnificent Seven
There are seven dietary supplements that have been evaluated in research studies of endurance athletes:
- Rhodiola – helps improve oxygen transfer from lungs to red blood cells
- Cordyceps – helps speed transfer of oxygen from red blood cells to mitochondria
- Eurycoma – balances hormones (lower cortisol and higher testosterone)
- Quercetin – improves blood flow by dilating blood vessels
- Arginine – improves blood flow by dilating blood vessels
- Eleuthero – provides resistance to physical stress and increases energy levels
- Ashwagandha – provides resistance to mental stress and induces relaxation
Rhodiola is a Himalayan root used by the Sherpa people to “adapt” to the stress of living and working at high altitudes. Even today, Sherpa climbers chew on rhodiola for an energy and endurance boost when helping mountaineers scale Mt. Everest. One mechanism for rhodiola’s anti-fatigue effects is an enhancement of oxygen efficiency – with subjects living at high altitude (5,380 meters) showing a beneficial effect of rhodiola supplementation on blood oxygen levels, time to exhaustion, VO2peak, and pulmonary ventilation during endurance exercise.
Cordyceps is a Tibetan mushroom used in traditional Chinese medicine (TCM) for “lung protection” and to balance the “Qi” – the fundamental “energy of life.” In clinical studies, cordyceps feeding results in significant improvements in fatigue, oxygen uptake, and endurance exercise performance.
Eurycoma is a root, often called Malaysian ginseng, that is used as a traditional remedy in Southest Asia (Malaysia, Thailand, Vietnam) to help individuals “adapt” to the reduced energy and depressed mood that often come with chronic stress and overtraining. Eurycoma contains a group of small peptides that are effective in restoring the balance between the catabolic hormone cortisol and the anabolic hormone testosterone.
Quercetin (an antioxidant) and arginine (an amino acid) have been used effectively to improve blood flow in patients with high blood pressure and heart disease – and have become popular in some endurance supplements, but it is unknown whether or not the small levels typically contained in some supplements would be effective in improving endurance performance.
Eleuthero (Siberian ginseng) and ashwagandha (Indian ginseng) are used in traditional medicine as “adaptogens” to help the body adapt to stressful situations. Eleuthero tends to be more “energizing” while Ashwagandha is regarded as more “relaxing” in its effects.
How to Use Them
Dosage ranges to consider are listed below and are dependent on delivery of effective levels of the active compounds – rather than to the total amount of the herb itself. Pay attention to product labels, which are required to list the percentage of active compounds provided by each herbal extract. For example, one product might provide 1,000mg of a low-potency cordyceps (and a low content of the active adenosine compounds), while another product might deliver a lower total amount of cordyceps, but at a higher potency with a higher level of active adenosine. Focus on the total amount (percentage) of active compounds rather than the absolute amount (milligrams) of each herb to maximize the endurance effects and your performance benefits.
- Rhodiola = 150-300mg (standardized to 5-6% rosavins)
- Cordyceps = 100-500mg (standardized to 5-10% adenosine)
- Eurycoma = 25-50mg (standardized to 20-25% eurypepides)
- Quercetin = 100-300mg (pure)
- Arginine = 2,000-3,000mg (pure)
- Eleuthero = 100-200mg (standardized to 0.5-1% eleutherosides)
- Ashwagandha = 10-30mg (standardized to 5-10% withanolides)
No amount of any herb is going to take you from the couch to the podium without your dedication to proper training and nutrition. However, if you’re already doing what you can in terms of diet and exercise, then adding a daily supplement to enhance the effects of your training might serve as a “biochemical tune-up” for your body and help you reach the next level of performance.
Shawn Talbott holds a MS in exercise science (UMass) and a PhD in nutritional biochemistry (Rutgers) and competes in iron-distance triathlons and ultramarathons.