You spend a lot of time and energy pumping iron, so you want to get as much benefit from it as possible. And that means you have to eat (or drink) the right thing after your work-out.
So a new study should be of interest. It finds that a soy-dairy protein blend increases muscle mass better than whey protein alone.
In the study, published online in the Journal of Applied Physiology, researchers from the University of Texas Medical Branch found that using a protein blend of soy, casein and whey post-workout prolongs the delivery of select amino acids to the muscle for an hour longer than using whey alone.
It also shows a prolonged increase in amino acid net balance across the leg muscle during early post-exercise recovery, suggesting prolonged muscle building.
The study was conducted by researchers from UTMB in collaboration with DuPont Nutrition and Health.
"This study sheds new light on how unique combinations of proteins, as opposed to single protein sources, are important for muscle recovery following exercise and help extend amino acid availability, further promoting muscle growth," said Blake B. Rasmussen, chairman of UTMB's Department of Nutrition and Metabolism and lead researcher of the study.
The new research builds on an earlier publication reporting that a soy-dairy blend extends muscle protein synthesis when compared to whey alone, as only the blended protein kept synthesis rates elevated three to five hours after exercise. Together, these studies indicate that the use of soy-dairy blends can be an effective strategy for active individuals seeking products to support muscle health.
The double-blind, randomized clinical trial included 16 healthy subjects, ages 19 to 30, to assess if consumption of a blend of proteins with different digestion rates would prolong amino acid availability and lead to increases in muscle protein synthesis after exercise.
The protein beverages provided to study subjects consisted of a soy-dairy blend (25 percent isolated DuPont Danisco SUPRO soy protein, 50 percent caseinate, 25 percent whey protein isolate) or a single protein source (whey protein isolate). Muscle biopsies were taken at baseline and up to five hours after resistance exercise. The protein sources were ingested one hour after exercise in both groups.