Areta JL, Burke LM, Camera DM, West DW, Crawshay S, Moore DR, Stellingwerff T, Phillips SM, Hawley JA, Coffey VG. Reduced resting skeletal muscle protein synthesis is rescued by resistance exercise and protein ingestion following short-term energy deficit. The myofibrillar protein synthesis (MPS) response to resistance exercise (REX) and protein ingestion during energy deficit (ED) is unknown. In young men (n ϭ 8) and women (n ϭ 7), we determined protein signaling and resting postabsorptive MPS

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... during energy balance [EB; 45 kcal·kg fat-free mass (FFM) Ϫ1 ·day Ϫ1 ] and after 5 days of ED (30 kcal·kg FFM Ϫ1 ·day Ϫ1 ) as well as MPS while in ED after acute REX in the fasted state and with the ingestion of whey protein (15 and 30 g). Postabsorptive rates of MPS were 27% lower in ED than EB (P Ͻ 0.001), but REX stimulated MPS to rates equal to EB. Ingestion of 15 and 30 g of protein after REX in ED increased MPS ϳ16 and ϳ34% above resting EB (P Ͻ 0.02). p70 S6K Thr 389 phosphorylation increased above EB only with combined exercise and protein intake (ϳ2-7 fold, P Ͻ 0.05). In conclusion, short-term ED reduces postabsorptive MPS; however, a bout of REX in ED restores MPS to values observed at rest in EB. The ingestion of protein after REX further increases MPS above resting EB in a dose-dependent manner. We conclude that combining REX with increased protein availability after exercise enhances rates of skeletal muscle protein synthesis during short-term ED and could in the long term preserve muscle mass.