With lots of marketing hype around sports products, our Sports Naturopath, Kate Smyth believes it is important to critically evaluate the evidence behind any claims. As interest in herbal medicines is increasing among athletes, we thought we’d share some insights from recently published medical journals.
The area of sports performance and sports products can be confusing but by sharing evidence-based information, we hope to create greater awareness and empower you to make informed decisions. Please keep in mind, this information is general in nature and does not qualify as specific advice for your individual sport or health status.
Many sports products are underpinned by large marketing budgets, whereas many natural products demonstrate clinical results but unfortunately allocated limited research budgets in regards to their effects on sports performance.
Plants provide nutritious macro-nutrients such as carbohydrates and lipids. Herbal medicines also contain active compounds that reduce infections and inflammation. Their applications are very broad from improving cardiovascular health to balancing hormones. The most popular herbs contain antioxidant properties that play a role in reducing oxidative stress, enhancing muscle recovery and energy with intensive exercise. In this post we’ll investigate just four of the herbs used by athletes namely Green Tea, Ginseng, Turmeric, and Tribulus.
Green tea extract
Green tea extract (Camilla Sinensis) is often found in weight management and stimulating supplements. Green tea extract (GTE) contains polyphenols, and antioxidants reported to increase fat utilisation. The phytonutrients in green tea have also been shown to inhibit pro-inflammatory substances and improve tendon, cartilage and collagen in athletes. Unfortunately, the majority of poor quality (yet widely available) GTE products do not declare their level of active ingredients and therefore provide very mixed results for athletes.
Dietary inclusion of GTE antioxidants is well supported. A 2017 clinical trial involving 54 soccer players taking GTE demonstrated significant improvements in oxidative status over a six week period (Hadi,2017). A subsequent study involving cyclists, demonstrated positive effects on neuromuscular function, reduced oxidative stress and muscle damage with cumulative exercise (Machado, 2018). Other studies suggest it may improve body mass and composition in athletes (Sellami, 2018).
I encourage athletes to use GTE as a substitute for coffee with limited withdrawal side effects. Although the average cup of pure green tea usually contains around 25 milligrams of caffeine, this is considered to be low when compared to around 100-180 milligrams in a typical coffee as mentioned in our blog here.
Synopsis: Green tea extract is a great source of antioxidants. Clinical trials focused on weight loss do not include well-trained athletes and therefore the relevance of results remain questionable. Whilst green tea is well researched by credible sources such as the Cochrane Review (Jurgens, 2012), in my opinion GTE supplements do not deliver significant weight loss benefits over and above a sound nutritional and exercise plan to warrant the marketing hype. Green tea is however a great alternative to coffee and absolutely delicious as a matcha latte or in bliss balls. See recipe here
When considering herbs for sports performance, the ginseng family is widely studied and praised for its support of physical endurance. There are many different forms of ginseng. The root of Korean ginseng (Panex Ginseng) is widely recognised for its anti-inflammatory, antioxidant, immune enhancing and endurance performance benefits. It also contains vitamins A, B, C and E along with iron, magnesium, potassium, phosphorous and ginsenoside active compounds.
A 2018 study demonstrated ginseng’s anti-fatigue effects related to its reduction in creatine kinase and blood urea nitrogen (Yan et al). Other studies suggest that use over a nine week period may improve aerobic capacity, (Vo2max), physical performance, lactate production and heart rate in athletes.
Its medicinal use extends to erectile dysfunction, libido, weakness, poor memory, cardiovascular issues, fatigue in menopausal women, and cognitive function. For information on other useful herbs during menopause click here
Synopsis: Ginseng’s inclusion in nearly 8000 research papers in PubMed suggests this herb deserves consideration, especially in athletes with fatigue, however conclusive evidence in large well-controlled studies relating to direct performance benefits, is still lacking.
Turmeric Curcuma Longa is the most well research root in the world and renown for its antioxidant, anti-inflammatory and hepatoprotective coumarin agents. In clinical practice it is widely prescribed for inflammatory conditions such as arthritic joint conditions, liver and digestive issues, cancer, neurodegenerative disease and autoimmune conditions.
Turmeric has benefits for marathoners, downhill runners, and weight trainers by attenuating muscle inflammation caused by training and competition through reducing inflammatory cytokines (Silalertdetkul, 2013). Some researchers suggest curcumin may serve as a more effective anti-inflammatory agent than ibuprofen during and following heavy exertion (Davis, 2007).
A study involving male master cyclists showed a significant reduction in advanced glycation end-products (AGEs) which are associated with stiffening of skeletal muscle, tendons, joints, bone, heart, arteries and lung with turmeric use (Chilelli, et al. 2016). A recent 2020 systemic review concluded turmeric before, during and up until 72 h’ post-exercise, improved performance by modulating the inflammation caused by physical activity (Fernández-Lázaro et al. 2020).
Synopsis: Turmeric’s appearance in over 15,000 published research papers provides credibility behind its anti-inflammatory capabilities for recovery and injuries . Turmeric is generally well tolerated in therapeutic doses without significant side-effects. Sufficient levels of active curcumin is difficult to obtain through dietary intake alone and therefore supplementation may be beneficial for some athletes. Professional guidance around its bioavailability and quality is however imperative in order to obtain its reported benefits.
Tribulus Tribulus Terrestris gained popularity amongst eastern European male athletes for its reported ability to improve testosterone, muscle growth and libido in power and weight-lifting athletes. Tribulus is used medicinally for hormonal support in both men and women. Tribulus contains steroidal saponins, such as diosgenin and phytosterols with beneficial effects on reproductive, urinary and cardiovascular systems.
Many of the recent studies investigating the anabolic and androgenic action of Tribulus are poorly designed and provide conflicting results. A 2008 study was unable to reveal a significant variation or increased above the WADA cut-off limits testosterone (Saudan,2008). Another study on Australian rugby union players failed to use adequate therapeutic levels of Tribulus.
Synopsis: Although considered a relatively safe herb by clinicians, this plant has been targeted for contamination with illegal substances in supplements. Some supplements containing Tribulus have led to positive doping control tests. Therefore this herb should be avoided by elite athletes. Read the blog “Supplements and what all athletes should know” here . In our opinion further research is warranted before safe and effective recommendation of this herb for sports performance can be provided.
As with all natural medicines, just because they are “natural” does not necessarily imply they are safe or without side effects or interactions with other medications. Therefore, athletes should consult with a qualified herbal practitioner who is across drug controls before self prescribing.
For further information on the suitability of these options for your particular situation, book in for an individual assessment with our Sports Naturopath Kate Smyth here