400 milligrams a day (mg/day) of this proprietary lemon verbena extract (Recoverben) resulted in a muscle strength reduction of 11% compared to 21% for the placebo group after exercise.
Additionally, lemon verbena appeared to not only speed recovery, but also reduce fatigue directly after exercise with complete recovery reported after 48 hours.
“It appears, that supplementation with lemon verbena extract strengthens the antioxidative defence system and enables effective counteraction of oxidative stress, but only if needed,” the German research team observed.
“The use of supplements with antioxidative or anti-inflammatory effects in the sports nutrition is already widespread.
“Similar results were found in other natural ingredients for effects of muscle strength and muscle damage, such as pomegranate extract and blueberry. These natural ingredients are high in polyphenols, a trait shared by lemon verbena.”
Recoverben’s makers, Vital Solutions, who also sponsored the study, pointed to previous research that identifies the product as high in polyphenols as well as exhibiting antioxidative and anti-inflammatory effects.
However, specific effects of lemon verbena on muscle damage, muscle soreness, and recovery needs have not been extensively studied.
One human pilot study investigating the extract on the muscular damage biomarker, creatine kinase and liver biomarker related to oxidative stress showed some effects on cytokines and oxidative stress markers in neutrophils.
Exhaustive exercise
The study was performed on 44 healthy males and females, aged 22–50 years old and active in sports.
These subjects were randomised to 400 mg lemon verbena extract once daily or placebo (maltodextrin).
All subjects were instructed to take two capsules daily in the morning. Products were consumed 10 days before an exhaustive exercise test, during the test day and four days after the test.
Subjects were asked to perform 200 countermovement jumps with an additional load of 10% of the participant’s body weight.
Muscle strength (MVC), muscle damage (CK), oxidative stress (GPx), inflammation (IL6) were noted to evaluate muscle damage and antioxidative capacity.
Volunteer-reported muscle soreness intensity were also assessed pre and post exercise.
Biomarker results
MVC and muscle soreness were notably less reduced after exercise in the lemon verbena extract group. The research team also found CK to be significantly increased above baseline at 24 hours.
Likewise, GPxP activity within the lemon verbena group increased compared to placebo group.
Only an increase of IL-6 was observed after exercise, without significant differences but high variability amongst subjects. Differences between groups were not significant.
“Increasing concentration of CK in the blood is an indication of muscle damage, being frequently used in sports nutrition studies,” the study said in explaining the findings.
“In our study, high levels of interindividual variation in CK concentrations were present, which could explain why we failed to observe a significant between-group difference despite other markers of muscle damage, such as MVC, favouring the lemon verbena group.
Along with the polyphenols’ antioxidant and anti-inflammatory capabilities, the team also proposed an enhanced production of vasodilation factors and the inhibition of synthesis of vasoconstrictors as possible mechanisms of action.
These could be additionally beneficial by improving tissue oxygen supply and removal of metabolic waste products, the study concluded.
Source: Journal of the International Society of Sports Nutrition
Published online ahead of print: doi.org/10.1186/s12970-018-0208-0
“Effects of lemon verbena extract (Recoverben®) supplementation on muscle strength and recovery after exhaustive exercise: a randomized, placebo-controlled trial.”
Authors: Sybille Buchwald-Werner, Ioanna Naka, Manfred Wilhelm, Elivra Schütz, Christiane Schoen and Claudia Reule