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Commentary on viewpoint: a time for exercise: the exercise window

Journal Article


Abstract


  • TO THE EDITOR: Dr. Chacko provides an interesting viewpoint on

    the optimal time to exercise for glycemic control (1). While

    intuitive to suggest that moderate-intensity exercise in the midpostprandial

    state might best normalize blood glucose, other

    factors warrant consideration. Patterns of exercise and its intensity,

    along with diabetes classification, require individualized

    attention because they differentially influence glucose/insulin levels

    (2, 3) and underlying phenotype. Immediately after highintensity

    interval exercise, blood glucose is reduced, independent

    of whether it is performed before or after breakfast (4), an effect

    that is greater in magnitude than with moderate-intensity exercise

    (2, 4). As indicated (1), whether exercise timing matters for

    chronic effects is unknown (notwithstanding the importance of

    acute effects). Research is urgently needed to determine whether

    acute exercise-induced responses translate to chronic adaptations

    underlying improved insulin sensitivity and beta-cell function.

    Some studies have examined exercising fasted vs. fed. Training

    fasted or at higher intensities appears likely to elicit greater muscle

    and whole body adaptations (5), including reduced lipid deposition

    that impairs insulin signaling, and greater transcriptional

    regulation of proteins involved in glucose disposal (i.e., GLUT-4,

    AMPK). Further research is needed to determine the long-term

    effects of fasted exercise on preventing and treating T2DM. Ultimately

    the diversity of human physiology, disease progression (and

    treatment) and individual behaviors (e.g., feeding pattern) complicates

    a “one-size-fits-all” optimal exercise prescription. Also important

    to consider are other risks (e.g., morning-impaired cardiovascular

    control) balanced against the proven benefits of exercise and a need

    to promote exercise compliance at the population level.

Authors


  •   Dr Monique Francois
  •   Hawley, John A. (external author)
  •   Cotter, Jim D. (external author)

Publication Date


  • 2017

Citation


  • Francois, M. E., Hawley, J. A. & Cotter, J. D. (2017). Commentary on viewpoint: a time for exercise: the exercise window. Journal of Applied Physiology, 122 (1), 210-210.

Scopus Eid


  • 2-s2.0-85032188589

Number Of Pages


  • 0

Start Page


  • 210

End Page


  • 210

Volume


  • 122

Issue


  • 1

Place Of Publication


  • United States

Abstract


  • TO THE EDITOR: Dr. Chacko provides an interesting viewpoint on

    the optimal time to exercise for glycemic control (1). While

    intuitive to suggest that moderate-intensity exercise in the midpostprandial

    state might best normalize blood glucose, other

    factors warrant consideration. Patterns of exercise and its intensity,

    along with diabetes classification, require individualized

    attention because they differentially influence glucose/insulin levels

    (2, 3) and underlying phenotype. Immediately after highintensity

    interval exercise, blood glucose is reduced, independent

    of whether it is performed before or after breakfast (4), an effect

    that is greater in magnitude than with moderate-intensity exercise

    (2, 4). As indicated (1), whether exercise timing matters for

    chronic effects is unknown (notwithstanding the importance of

    acute effects). Research is urgently needed to determine whether

    acute exercise-induced responses translate to chronic adaptations

    underlying improved insulin sensitivity and beta-cell function.

    Some studies have examined exercising fasted vs. fed. Training

    fasted or at higher intensities appears likely to elicit greater muscle

    and whole body adaptations (5), including reduced lipid deposition

    that impairs insulin signaling, and greater transcriptional

    regulation of proteins involved in glucose disposal (i.e., GLUT-4,

    AMPK). Further research is needed to determine the long-term

    effects of fasted exercise on preventing and treating T2DM. Ultimately

    the diversity of human physiology, disease progression (and

    treatment) and individual behaviors (e.g., feeding pattern) complicates

    a “one-size-fits-all” optimal exercise prescription. Also important

    to consider are other risks (e.g., morning-impaired cardiovascular

    control) balanced against the proven benefits of exercise and a need

    to promote exercise compliance at the population level.

Authors


  •   Dr Monique Francois
  •   Hawley, John A. (external author)
  •   Cotter, Jim D. (external author)

Publication Date


  • 2017

Citation


  • Francois, M. E., Hawley, J. A. & Cotter, J. D. (2017). Commentary on viewpoint: a time for exercise: the exercise window. Journal of Applied Physiology, 122 (1), 210-210.

Scopus Eid


  • 2-s2.0-85032188589

Number Of Pages


  • 0

Start Page


  • 210

End Page


  • 210

Volume


  • 122

Issue


  • 1

Place Of Publication


  • United States