Improved Endurance Running Performance Following Haskap Berry (Lonicera caerulea L.) Ingestion

Background: Food high in (poly)phenolic compounds, such as anthocyanins, have the potential to improve exercise recovery and exercise performance. Haskap berries are rich in antho-cyanins, but no research has examined the potential to improve human performance. The aim of this study was to determine the influence of Haskap berry on parameters of endurance running perfor-mance. Methods: Using a double-blind, placebo controlled, independent groups design, 30 male recreational runners (mean ± SD age, 33 ± 7 years; stature, 178.2 ± 7.2 cm; mass, 77.7 ± 10.6 kg; . VO_2peak, 52.2 ± 6.6 mL/kg/min) volunteered to participate. Following familiarisation, volunteers visited the laboratory twice (separated by seven days) to assess submaximal, maximal and 5 km time trial running performance. After the first visit, volunteers were randomly assigned to consume either the Haskap berry intervention or an isocaloric placebo control. Results: There were modest changes in heart rate and^.VO₂ at submaximal intensities (p < 0.05). Time to exhaustion during the VO_2peak test was longer in the Haskap group by 20 s (p = 0.031). Additionally, 5 km time trial performance was improved in the Haskap group by ~21 s (p = 0.016), which equated to a 0.25 km/h increase in mean running speed compared to the placebo control; this represented a >2% improvement in running performance. Conclusions: The application of this newly identified functional food to athletes has the capacity to improve endurance running performance.