Study to explore potential benefits of Rooibos tea
A TEAM of scientists from the Cape Peninsula University of Technology (CPUT) and the Prime Human Performance Institute in Durban will test the extent to which homegrown Rooibos tea could aid sportsmen and women.
In a previous study, led by Professor Jeanine Marnewick, at CPUT’s Oxidative Stress Research Centre, researchers found that Rooibos plays a preventative role in exercise-induced oxidative stress, meaning that its abundance of antioxidants works in unison to resist cell damage, which often occurs during high-intensity bursts of exercise.
CPUT Sports Management Department Professor Simeon Davies explained that these studies demonstrated that during repeated exhaustive exercise bouts Rooibos can reduce physical fatigue allowing for improved performance.
“In gist, oxidative stress can be defined as an imbalance between oxidants and antioxidants in favour of oxidants – also known as free radicals. Since oxidants are unstable molecules, they can cause damage to vital cell components, such as genetic material, lipids and proteins.
“Free radicals are derived from organisms and cells inside the body and the outside environment, such as cigarette smoke, heavy metals, pesticides and certain medication, but can also occur as a result of strenuous exercise when our bodies use oxygen to produce energy,” Davies said.
To prevent free radical damage, the body has a natural defence system of antioxidants that can combat the damage caused by oxidants, but it’s often not sufficient under certain conditions, such as strenuous physical activity, he said.
“The initial oxidative stress study already showed that drinking Rooibos in a concentrated form – equivalent to six cups a day – boosted performance during repeated arm flexion/extension work by around 5%, which may have interesting implications for usage in elite sports, where every percentage point counts during competition, but may also allow for improved training that could in itself elevate competition times,” Davies said.
To build on these findings, a more comprehensive study will be done in a simulated and controlled hypoxic (low oxygen) environment simulating high altitude (3 500m).
The study will involve 50 relatively fit individuals between the ages of 18 and 60.
On test day, each participant will consume a specially prepared tonic consisting of water and concentrated Rooibos or a placebo. Physical performance will be measured on calibrated Wattbikes, while oxidative stress and other related stress markers will be measured via blood samples to evaluate the efficacy of Rooibos during strenuous exercise.
The hypoxic element to the study aims to investigate Rooibos’s ability to combat high altitude sickness (HAS). Exercising at high altitude induces a high degree of oxidative stress, which is often associated with HAS. In a pilot study, led by Davies in 2015, eight climbers supplemented with Rooibos in a concentrated pill form while summiting Mount Aconcagua, which at 6 962m is the highest mountain in the southern hemisphere.
Preliminary findings from the Aconcagua expedition found Rooibos to be an effective supplement that appeared to mitigate the effects of HAS.
This study will take place at the Prime Human Performance Institute at Moses Mabhida Stadium.
Davies said if Rooibos proved successful in the studies that are to follow, it could become a staple food supplement for elite athletes the world over.
“It’s exciting to think that a South African indigenous plant such as Rooibos may become athletes’ next musthave supplement. In the notso-distant future, concentrated Rooibos may also become available to consumers in tablet or tonic form to naturally elevate antioxidant levels in the body, reducing risk of other chronic diseases, such as cardiovascular disease and diabetes,” Davies said.