Is soy milk a better recovery aid compared to semi-skimmed milk after exercise? does it increase time to exhaustion in trained cyclists?
Introduction Milk has been proven to be a popular recovery drink for trained cyclists to achieve high profile results because milk contains carbohydrates and protein. On the other hand, research has now shown that Soy milk can be just as effective as semi skimmed milk as it contains the same high quality protein.
Method For the first visit, eight male trained cyclists took part in a maximum oxygen consumption test (VO2max) to determine each participant's VO2 max and maximum power output (Pmax).
The second visit consisted of the glycogen depletion trial where each participant had to cycle at 90% of their Pmax for 2 min and then cycle for 2 min at 50% of their Pmax. This was in a form of intervals and continued until participants could no longer maintain their pedal rate. The percentage was then decreased to 80%, 70% and 60%.
This was followed by a 4 h recovery period. Participants were given 355 ml of soy milk or semi-skimmed milk in a double blind, randomised design at the start and then 2 h into the recovery process. Both drinks were masked with 10 g of cocoa powder.
The Endurance trial followed which required participants to cycle at 70% of their Pmax until exhaustion. Heart rate, body hydration, blood lactate, food diaries and gastrointestinal distress questionnaire were variables that were also measured throughout.
Results Time to exhaustion at the end of the endurance trial showed six out of eight participants cycled for longer with semi-skimmed milk (11.9±3.6 min). Only two participants cycled longer with soy milk (9.9±3.2 min). There were no significant differences in the results or any of the variables measured.
Conclusion The present study did not reveal significant results when testing for the relevance of the ingestion of soy milk over semi-skimmed milk.