Acute Testosterone Administration Does Not Affect Muscle Anabolism

Discussion in 'Men's Health Forum' started by Michael Scally MD, Aug 24, 2019.

  1. Michael Scally MD

    Michael Scally MD Doctor of Medicine

    [OA] Acute testosterone Administration Does Not Affect Muscle Anabolism

    We previously demonstrated that improved net muscle protein balance, via enhanced protein synthetic efficiency, occurs 5 days after testosterone (T) administration. Whether the effects of T on muscle protein kinetics occur immediately upon exposure is not known.

    We investigated the effects of acute T exposure on leg muscle protein kinetics and selected amino acid (AA) transport using the arteriovenous balance model, and direct calculations of mixed-muscle protein fractional synthesis (FSR) and breakdown (FBR) rates. Four healthy men were studied over a 5 h period with and without T (infusion rate, 0.25 mg·min− 1).

    Muscle protein FSR, FBR, and net protein balance (direct measures and model derived) were not affected by T, despite a significant increases in arterial (p = 0.009) and venous (p = 0.064) free T area under the curve during T infusion. T infusion had minimal effects on AA transport kinetics, affecting only the outward transport and total intracellular rate of appearance of leucine.

    These data indicate that exposing skeletal muscle to T does not confer immediate effects on AA kinetics or muscle anabolism. There remains an uncertainty as to the earliest discernable effects of T on skeletal muscle protein kinetics after initial administration.

    Church DD, Pasiakos SM, Wolfe RR, Ferrando AA. Acute testosterone administration does not affect muscle anabolism. Nutr Metab (Lond). 2019;16:56. Acute testosterone administration does not affect muscle anabolism