Author(s): MANDERS, R., HUNT, J., KING, D., Institution: UNIVERSITY OF SURREY, Country: UNITED KINGDOM, Abstract-ID: 2032

INTRODUCTION:
New Zealand Blackcurrants (NZBC) have been well described as ergogenic aids. It has been postulated that the NZBC related performance effects could be the result of a better oxygen delivery to the muscles, which in turn could lead to an improved running economy (RE) and substrate utilisation. We aimed to investigate the effects of 7-day NZBC supplementation on 5km running performance, running economy and substrate utilisation in trained male and female runners.
METHODS:
9 males (31.8±10.3y, BMI:23.4±2.3 kg/m2, VO2max:52.1±6.5 mL/kg/min) and 9 females (31.2±9.5y, BMI:21.8±2.1 kg/m2, VO2max:47.2±5.8 mL/kg/min) were recruited. Using a double-blind, randomised, placebo controlled, cross-over design, participants received 600 mg/day NZBC extract (containing 210 mg anthocyanins) or a placebo (PLA) for 7 days prior to assessing RE and metabolic responses at 75%, 85% and 95% of LT2 followed by a 5km time trial (TT). RE and metabolic parameters were determined via breath-by-breath analysis and TT performance by completion time.
RESULTS:
The 5km TT was completed in 1355±147s and 1191±100s for females and males resp. in PLA. NZBC supplementation did not have significant effects on TT performance in males (1215±118s, P=0.2). In the female group there was a strong trend toward improved TT performance with a completion time of 1335±158s (P=0.051). RE was lower at the higher (95% and 85%LT2) intensities compared to 75%LT2 at a group level for both PLA (184.0±12.61, 188.3±14.13 and 198.0±17.02 mL/kg/km, resp. P<0.05) and NZBC (180.1±14.56, 181.1±15.82 and 190.2±15.52 mL/kg/km, resp. P<0.05). No significant differences were found in RE between trials at group level for females and males at the different intensities (P>0.05). NZBC did not alter total energy expenditure at 75%, 85% or 95%LT2 when compared to PLA at a group (11.2±2.31, 12.7±3.04, 14.2±3.54 kcal/min vs. 11.9±2.44, 13.3±2.77, 14.9±3.21kcal/min resp. (P>0.1) or gender specific level. Carbohydrate and fat oxidation also did not differ between PLA and NZBC (P>0.1).
CONCLUSION:
7 Days of New Zealand Blackcurrant supplementation did not significantly improve running economy, performance or substrate use in trained runners but there was a strong trend towards improved performance for female athletes. These results underline the differences between male and female physiology and the need for more gender specific research.