These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Resistance training reduces the acute exercise-induced increase in muscle protein turnover.
    Author: Phillips SM, Tipton KD, Ferrando AA, Wolfe RR.
    Journal: Am J Physiol; 1999 Jan; 276(1):E118-24. PubMed ID: 9886957.
    Abstract:
    We examined the effect of resistance training on the response of mixed muscle protein fractional synthesis (FSR) and breakdown rates (FBR) by use of primed constant infusions of [2H5]phenylalanine and [15N]phenylalanine, respectively, to an isolated bout of pleiometric resistance exercise. Trained subjects, who were performing regular resistance exercise (trained, T; n = 6), were compared with sedentary, untrained controls (untrained, UT; n = 6). The exercise test consisted of 10 sets (8 repetitions per set) of single-leg knee flexion (i.e., pleiometric muscle contraction during lowering) at 120% of the subjects' predetermined single-leg 1 repetition maximum. Subjects exercised one leg while their contralateral leg acted as a nonexercised (resting) control. Exercise resulted in an increase, above resting, in mixed muscle FSR in both groups (UT: rest, 0.036 +/- 0.002; exercise, 0.0802 +/- 0.01; T: rest, 0.045 +/- 0.004; exercise, 0.067 +/- 0.01; all values in %/h; P < 0.01). In addition, exercise resulted in an increase in mixed muscle FBR of 37 +/- 5% (rest, 0.076 +/- 0.005; exercise, 0.105 +/- 0.01; all values in %/h; P < 0.01) in the UT group but did not significantly affect FBR in the T group. The resulting muscle net balance (FSR - FBR) was negative throughout the protocol (P < 0.05) but was increased in the exercised leg in both groups (P < 0.05). We conclude that pleiometric muscle contractions induce an increase in mixed muscle protein synthetic rate within 4 h of completion of an exercise bout but that resistance training attenuates this increase. A single bout of pleiometric muscle contractions also increased the FBR of mixed muscle protein in UT but not in T subjects.
    [Abstract] [Full Text] [Related] [New Search]