Coconut water (CW) has been among the hottest beverage trends over the past five years, and is often thought of as a healthier alternative to the more traditional sugar-laden sports drinks people consume during exercise. Though marketed primarily as a general use drink, it has gained popularity as a sports drink. This is because it naturally contains both carbohydrate and electrolytes, despite having an overall middling micronutrient content (as shown in Figure 1).
Unrelated to exercise, its proponents often remark that coconut water can be prepared to be given intravenously without complications, as its osmolarity (concentration of a solution) matches that of our blood. While the osmolarity of coconut water may be similar to that of human blood, that does not necessarily make it a better sports drink than those commercially available. Several studies have looked at CW as a way of improving rehydration after exercise with fairly unremarkable results. One study[1] found CW was better than plain water at rehydrating after exercise, but not any better than commercial sports drink that contained adequate sodium. Two other studies[2][3] found no significant differences in rehydration between CW and plain water.

One study that looked at the effects of CW consumption prior to exercise found no differences in exercise capacity when compared to consumption of sports drinks or plain water. In contrast, other research has found that drinking CW prior to exercise did result in an improved “time to exhaustion” for cycling exercise performed in a hot environment. Findings from these studies also show that individuals consuming CW reported gastrointestinal distress more frequently.
No study to date has examined CW consumed by participants during exercise, and so any performance-enhancing (or detracting) effects are unknown. Accordingly, the aim of this new study was to examine the effects of CW compared with plain water on hydration and performance. Secondary outcomes were palatability and voluntary intake of CW during intense exercise.
Coconut water is often touted as a healthier sports drink, although research looking at its effects on performance, particularly when consumed during exercise, is lacking. This new study was set up to examine the effects of coconut water on hydration and exercise performance.