Abstract

A double blind, placebo-controlled, randomized human study was conducted to evaluate the effect of Morinda citrifolia (noni) fruit juice on aerobic fitness of cyclists. Twenty volunteers drank 120 mL of noni juice, or a placebo, for 14 days. Another 10 volunteers comprised a reference group. Modest increases in oxygen uptake at 50 Watt workload (p = 0.005) and VO₂ max (p = 0.009) occurred in the noni juice group, but a longer study is needed. However, the results suggest that fitness benefits previously observed in a three week clinical trial may begin to appear in some individuals within 2 weeks of noni juice supplementation. Phytochemicals present in noni juice, but not in the placebo, were scopoletin (17.07±0.64 μg/mL), asperulosidic acid (36.00±11.27 μg/mL) and deacetylasperulosidic acid (435.67±46.48 μg/mL). The noni juice evaluated in this trial did not contain any anabolic androgenic steroids or stimulants. Therefore, the fitness promoting properties of noni juice may be associated predominantly with presence of iridoids.

Keywords:

Human study, noni juice, VO₂ max,

References

Competing interests

The authors have no competing interests.

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The authors have no competing interests.