madman
Super Moderator
Myofibrillar and Mitochondrial Protein Synthesis Rates Do Not Differ in Young Men Following the Ingestion of Carbohydrate with Whey, Soy, or Leucine-Enriched Soy Protein after Concurrent Resistance- and Endurance-Type Exercise
ABSTRACT
Background: Protein ingestion during recovery from resistance-type exercise increases postexercise muscle protein synthesis rates. Whey protein has been reported to have greater anabolic properties than soy protein, an effect which may be attributed to the higher leucine content of whey.
Objective: The objective of this study was to compare postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) proteinsynthesisratesafteringestionofcarbohydratewithwhey,soy,orsoyproteinenrichedwithfreeleucine(tomatch the leucine content of whey) during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men.
Methods: In a randomized, double-blind, parallel-group design, 36 healthy young recreationally active men (mean ± SEM age: 23±0.4 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and L-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 20 g protein from whey (WHEY), soy (SOY), or leucine-enriched soy (SOY+LEU) after concurrent resistance- and endurance-type exercise. Blood and muscle biopsies were collected over a 360 min postexercise recovery period to assess MyoPS and MitoPS rates, and associated signaling through the mammalian target of rapamycin complex 1 (mTORC1).
Results: Postprandial peak plasma leucine concentrations were significantly higher in WHEY (mean±SEM: 322±10 μmol/L) and SOY + LEU (328 ± 14 μmol/L) compared with SOY (216 ± 6 μmol/L) (P < 0.05). Despite the apparent differences in plasma leucinemia, MyoPS(WHEY:0.054±0.002;SOY:0.053±0.004;SOY+LEU:0.056±0.004%·h−1; P=0.83), and MitoPS (WHEY: 0.061±0.004; SOY: 0.061±0.006; SOY+LEU: 0.063±0.004%·h−1; P=0.96) rates over the entire 360 min recovery period did not differ between treatments. Similarly, signaling through mTORC1Ser2448, p70S6kThr389, 4E-BP1Thr37/46, and rpS6Ser235/236 was similar between treatments.
Conclusion: Postexercise MyoPS and MitoPS rates do not differ after co-ingestion of carbohydrate with 20 g protein from whey, soy, or leucine-enriched soy protein during 360 min of recovery from concurrent resistance- and endurance type exercise in young, recreationally active men.
In conclusion, co-ingestion of carbohydrate with 20 g whey, soy, or free leucine-enriched soy protein do not lead to differences in overall postexercise MyoPS or MitoPS rates during recovery from a single bout of concurrent resistance and endurance-type exercise in recreationally active young men. Increasing the leucine content of soy protein to match that of whey protein does not further increase postexercise MyoPS or MitoPS rates during 360 min of recovery from concurrent resistance- and endurance-type exercise.
ABSTRACT
Background: Protein ingestion during recovery from resistance-type exercise increases postexercise muscle protein synthesis rates. Whey protein has been reported to have greater anabolic properties than soy protein, an effect which may be attributed to the higher leucine content of whey.
Objective: The objective of this study was to compare postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) proteinsynthesisratesafteringestionofcarbohydratewithwhey,soy,orsoyproteinenrichedwithfreeleucine(tomatch the leucine content of whey) during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men.
Methods: In a randomized, double-blind, parallel-group design, 36 healthy young recreationally active men (mean ± SEM age: 23±0.4 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and L-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 20 g protein from whey (WHEY), soy (SOY), or leucine-enriched soy (SOY+LEU) after concurrent resistance- and endurance-type exercise. Blood and muscle biopsies were collected over a 360 min postexercise recovery period to assess MyoPS and MitoPS rates, and associated signaling through the mammalian target of rapamycin complex 1 (mTORC1).
Results: Postprandial peak plasma leucine concentrations were significantly higher in WHEY (mean±SEM: 322±10 μmol/L) and SOY + LEU (328 ± 14 μmol/L) compared with SOY (216 ± 6 μmol/L) (P < 0.05). Despite the apparent differences in plasma leucinemia, MyoPS(WHEY:0.054±0.002;SOY:0.053±0.004;SOY+LEU:0.056±0.004%·h−1; P=0.83), and MitoPS (WHEY: 0.061±0.004; SOY: 0.061±0.006; SOY+LEU: 0.063±0.004%·h−1; P=0.96) rates over the entire 360 min recovery period did not differ between treatments. Similarly, signaling through mTORC1Ser2448, p70S6kThr389, 4E-BP1Thr37/46, and rpS6Ser235/236 was similar between treatments.
Conclusion: Postexercise MyoPS and MitoPS rates do not differ after co-ingestion of carbohydrate with 20 g protein from whey, soy, or leucine-enriched soy protein during 360 min of recovery from concurrent resistance- and endurance type exercise in young, recreationally active men.
In conclusion, co-ingestion of carbohydrate with 20 g whey, soy, or free leucine-enriched soy protein do not lead to differences in overall postexercise MyoPS or MitoPS rates during recovery from a single bout of concurrent resistance and endurance-type exercise in recreationally active young men. Increasing the leucine content of soy protein to match that of whey protein does not further increase postexercise MyoPS or MitoPS rates during 360 min of recovery from concurrent resistance- and endurance-type exercise.
