March 24, 09
Improved Endurance capacity following chocolate milk consumption compared with two commercially available sports drinks. Kevin Thomas, Penelope Morris and Emma Stevenson. Applied Physiology, Nutrition and Metabolism. Vol 34 . 2009.
This study examined the effects of 3 recovery drinks on endurance performance following glycogen depleting exercise. Nine trained male cyclists performed 3 experimental trials, in a randomized counter balanced order, consisting of a glycogen depleting trial, a 4hour recovery period and a cycle to exhaustion at 70% power at maximal oxygen uptake.. At 0 and 2 hours into the recovery period, participants consumed chocolate milk (CM), a carbohydrate replacement drink (CR), or a fluid replacement drink (FM). Participants cycled 51 and 43% longer after ingesting the CM than after the CR or FR. CR is an effective recovery aid after prolonged endurance exercise for subsequent exercise at low to moderate intensities.
My take on it:
Well, this study was done by Mars, and I am pretty sure they have a chocolate milk product for sale in the UK! I have several athletes who do use chocolate milk post exercise and swear by it. It makes sense to me that it would aid with recovery as it contains both carbs and protein which when combined together enhance both glycogen re-synthesis and muscle repair and have a synergistic response. 8oz of milk contains 200 cals and about 31g carbs and 8g protein; an almost perfect 4:1 ratio! Additionally, the milk may increase free fatty acids which may help to explain why the subsequent exercise time to failure (TTF) was longer in the CM group. I do think that the same study should be done with a higher intensity TTF trial. And in the meantime, for athletes performing ultraendurance training, I would recommend a protocol that included all 3 (CM, CR, and FR) as their calorie intake needs are higher anyway and the amount of fluid lost through sweat is no doubt higher.