Haskap berry (Lonicera caerulea L., also known as blue honeysuckle) contains high levels of anthocyanin and polyphenols. These nutrient levels might contribute to improved cardiovascular health as well as physical performance. Haskap is also high in cyanidin-3-O-glucoside (C3G), a naturally occurring anthocyanin that may improve endothelial function and has potential to affect vascular function, inflammation, and oxidative stress. These properties make Haskap berry a prime candidate for improving aerobic performance in humans.
In a recent double-blind, placebo controlled trial published in Nutrients (DOI: https://doi.org/10.3390/nu14040780) researchers aimed to determine the influence of Haskap berry consumption on endurance running performance.
The 30 participants were non-smoking males aged 18-45 years with an average (mean) height of 178.2 cm and weight of 77.7 kg. Participants were not taking any additional supplements or medication that may have impacted the study results. The participants visited an environmentally controlled laboratory facility on three separate occasions during the study period. To investigate the effect of Haskap berry on aerobic performance, three tests (lactate threshold, VO2peak, and 5 km time trial) were used. During the first trip, participants' physical status was checked, they tested the treadmill, and completed a 5 km time trial. The second and third visits included all three experimental trials which were performed at the same time of day between sessions with similar environmental conditions.
Participants were divided into either the Haskap berry or placebo group, both supplements were mixed with no fat yoghurt to aid consumption. The Haskap berry intervention was a commercially available powder while the placebo was an unsweetened, artificially flavoured and colored Black Cherry KoolAid with added maltodextrin. During the trial, participants were provided with a standardized light meal. Throughout the study period, they were also advised to maintain their current diet and exercise but told to restrict foods high in polyphenols to a single portion per day.
The results showed lower heart rate and VO2 at submaximal intensities during the lactate threshold trial for the Haskap berry group. Time to exhaustion for the Haskap group was also longer by 20 seconds during the VO2peak test. The 5 km time trial also showed performance improvement by 21 seconds or 0.25 km/h in mean running velocity. This showed an improvement in running performance by >2%.
The researchers conclude that the collected data “[adds] to the growing body of evidence that dietary (poly)phenolic-rich foods could be helpful to enhance athletic performance, and critically offer exercisers a practical, non-pharmacological, food-based solution to support training and competition.