Muscle Mitochondrial Capacity Is Impaired Immediately Following Maximal Exercise, 2025, Dickinson et al

Discussion in 'Other health news and research' started by Mij, Jan 12, 2025.

  1. Mij

    Mij Senior Member (Voting Rights)

    Messages:
    10,144
    Abstract
    Mitochondria are essential in supplying energy to skeletal muscle. Near-infrared spectroscopy (NIRS) was developed to noninvasively assess mitochondrial capacity (mV̇O2max) as a rate constant of metabolic recovery after exercise.

    Purpose
    This study measured the time course mV̇O2max following both maximal and submaximal exercise.

    Methods
    Healthy male and female participants were tested (n = 12 maximal and n = 8 submaximal exercise). A NIRS device was placed on the left medial gastrocnemius. Participants performed either 1 min of maximal, rapid (~2 Hz), or submaximal (~0.37 Hz) plantar flexion exercise on a custom pneumatic ergometer. mV̇O2max was measured before and immediately after exercise. mV̇O2max measurements consisted of four incomplete recovery curves of muscle metabolism taken after 30 s of electrical muscle stimulation except in the first post-exercise to be consistent with the use of pre-exercise trial. The four recovery curves were collected 50-, 156-, 260-, and 366-s postexercise, each producing an mV̇O2max rate constant.

    Results
    After maximal exercise, muscle acceleration decreased to 52 ± 18% (P = 0.001) of prevalues. mV̇O2max was reduced from the pre-exercise mean at the first post-trial (2.16 ± 0.44 to 1.21 ± 0.52 min−1, P < 0.001). The fourth trial showed recovery from the first (2.2 ± 0.46 min−1 vs 1.21 ± 0.52 min−1, P < 0.001) and was not significantly different from pre-exercise values (2.2 ± 0.46 vs 2.16 ± 0.44 min−1, P = 0.41). No change in acceleration or mV̇O2max was seen after submaximal exercise (P > 0.05).

    Conclusions
    The 56.7% reduction in mV̇O2max supports the hypothesis that in young, healthy individuals, a minute of maximal exercise transiently impairs mV̇O2max, which then recovers within 6 min. The NIRS method shows promise in tracking time course changes in mV̇O2max and warrants further investigation of the transient effects of exercise on mV̇O2max.
    LINK
     

Share This Page