Essential amino acid-enriched whey enhances post-exercise whole-body protein balance during energy deficit more than iso-nitrogenous whey or a mixed-macronutrient meal: a randomized, crossover study.

ABSTRACT:

Background

The effects of ingesting varying essential amino acid (EAA)/protein-containing food formats on protein kinetics during energy deficit are undetermined. Therefore, recommendations for EAA/protein food formats necessary to optimize both whole-body protein balance and muscle protein synthesis (MPS) during energy deficit are unknown. We measured protein kinetics after consuming iso-nitrogenous amounts of free-form essential amino acid-enriched whey (EAA?+?W; 34.7?g protein, 24?g EAA sourced from whey and free-form EAA), whey (WHEY; 34.7?g protein, 18.7?g EAA), or a mixed-macronutrient meal (MEAL; 34.7?g protein, 11.4?g EAA) after exercise during short-term energy deficit.

Methods

Ten adults (mean?±?SD; 21?±?4 y; 25.7?±?1.7?kg/m²) completed a randomized, double-blind crossover study consisting of three, 5 d energy-deficit periods (-?30?±?3% of total energy requirements), separated by 14 d. Whole-body protein synthesis (PS), breakdown (PB), and net balance (NET) were determined at rest and in response to combination exercise consisting of load carriage treadmill walking, deadlifts, and box step-ups at the end of each energy deficit using L-[²H₅]-phenylalanine and L-[²H₂]-tyrosine infusions. Treatments were ingested immediately post-exercise. Mixed-muscle protein synthesis (mixed-MPS) was measured during exercise through recovery.

Results

Change (? postabsorptive + exercise to postprandial + recovery [mean treatment difference (95%CI)]) in whole-body (g/180?min) PS was 15.8 (9.8, 21.9; P?=?0.001) and 19.4 (14.8, 24.0; P?=?0.001) greater for EAA?+?W than WHEY and MEAL, respectively, with no difference between WHEY and MEAL. ?PB was -?6.3 (-?11.5, -?1.18; P?=?0.02) greater for EAA?+?W than WHEY and?-?7.7 (-?11.9, -?3.6; P?=?0.002) greater for MEAL than WHEY, with no difference between EAA?+?W and MEAL. ?NET was 22.1 (20.5, 23.8; P?=?0.001) and 18.0 (16.5, 19.5; P?=?0.00) greater for EAA?+?W than WHEY and MEAL, respectively, while ?NET was 4.2 (2.7, 5.6; P?=?0.001) greater for MEAL than WHEY. Mixed-MPS did not differ between treatments.

Conclusions

While mixed-MPS was similar across treatments, combining free-form EAA with whey promotes greater whole-body net protein balance during energy deficit compared to iso-nitrogenous amounts of whey or a mixed-macronutrient meal.

Trial registration

ClinicalTrials.gov, Identifier no. NCT04004715 . Retrospectively registered 28 June 2019, first enrollment 6 June 2019.

SUBMITTER: Gwin JA 

PROVIDER: S-EPMC7791816 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature