Both types of protein shakes boosted muscle protein building similarly in young men, whether they were resting or exercising after drinking them.
Scientific Claim
In 10 young healthy males, a single 10 g dose of β-lactoglobulin and whey protein isolate both increased skeletal muscle protein synthesis rates by 70-90% in the fed state and 90-130% in the fed-exercise state, with no significant differences between the two protein sources.
Original Statement
“FED MPS rates increased (main time effect: p < 0.0001; Figure 4A) in response to both WPI (0.042 ± 0.006%/h vs. 0.081 ± 0.009%/h; p = 0.0006) and BLG (0.048 ± 0.006%/h vs. 0.083 ± 0.008%/h; p = 0.0019), with no difference in response between supplements. Likewise, FED-EX MPS rates (n = 8; main time effect: p < 0.0001; Figure 4B) increased following both WPI (0.046 ± 0.006%/h vs. 0.106 ± 0.008%/h; p < 0.0001) and BLG (0.047 ± 0.007%/h vs. 0.090 ± 0.005%/h; p = 0.0008), with no difference between supplements.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The RCT design with direct MPS measurements allows definitive claims about the lack of difference between protein sources.
Evidence from Studies
Supporting (1)
The Effect of Leucine-Enriched β-Lactoglobulin Versus an Isonitrogenous Whey Protein Isolate on Skeletal Muscle Protein Anabolism in Young Healthy Males