Influence of Adjuvant Therapy in Cancer Survivors on Endothelial Function and Skeletal Muscle Deoxygenation

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Neuromuscular recovery from severe- and extreme-intensity exercise in men and women

Maximal voluntary contraction force (MVC), potentiated twitch force (Qpot), and voluntary activation (%VA) recover to baseline within 90s following extreme-intensity exercise. However, methodological limitations masked important recovery kinetics. We hypothesized reductions in MVC, Qpot, and %VA at task failure following extreme-intensity exercise would be less than following severe-intensity exercise, and Qpot and MVC following extreme-intensity exercise would show significant recovery within 120s but remain depressed following severe-intensity exercise. Twelve subjects (6 men) completed two severe-intensity (40, 50%MVC) and two extreme-intensity (70, 80%MVC) isometric knee-extension exercise bouts to task failure (Tlim). Neuromuscular function was measured at baseline, Tlim, and through 150s of recovery. Each intensity significantly reduced MVC and Qpot compared to baseline. MVC was greater at Tlim (pThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

The rate of change for tissue oxygenation index (TOI; Panel A), deoxygenated hemoglobin ([HHb]; Panel B), and total hemoglobin ([Hb]_total; Panel C) as a function of oxygen uptake (V˙O2).

<p>Note that the absolute change in TOI and [HHb] as a function of the increase <math><mrow><msub><mrow>V<mo>˙</mo>O</mrow><mn>2</mn></msub></mrow></math> during exercise were significantly less in cancer survivors compared to controls. Values are mean ± SE.</p

Near-infrared spectroscopy (NIRS)-obtained muscle oxygenation data at baseline, 50 W, and the ventilatory threshold (VT).

<p>Tissue oxygenation index (TOI; Panel A) in the cancer survivors remained at baseline levels throughout the test compared to the progressive decrease observed in controls. Deoxygenated hemoglobin ([HHb]; Panel B) was significantly lower in cancer survivors compared to controls at VT. Total hemoglobin ([Hb]_total; Panel C) at VT was significantly decreased in the cancer survivors compared to controls. Values are mean ± SE; † P<0.05 significantly different compared to baseline. * P<0.05 significantly different compared to controls.</p

Endothelium-dependent, flow-mediated, brachial artery dilation (FMD) in control and cancer survivors (CS).

<p>FMD values are shown normalized for the magnitude of the hyperaemic shear stimulus (i.e. % change in diameter divided by the AUC_SR).</p