Facebook
Twitter
LinkedIn
Email
 |
Checking for direct PDF access through Ovid | |
Excerpt
Using 31P magnetic resonance spectroscopy (MRS) we have recently shown that acute increases in volume and/or intensity of exercise have elicited long-term effects on the ability of muscle to generate ATP from oxidative phosphorylation (OxPhos). OxPhos was measured from the initial PCr recovery rate during the first 14-seconds of recovery following 90-seconds isometric plantar flexion exercises using 31P MRS. The following (figure) shows fluctuations in OxPhos consequent to three acute increases in volume/intensity of exercise that produced delayed onset muscle soreness (EXMS). OxPhos was decreased to less than 50% of pre-injury stress values even after 6 weeks post injury. Furthermore, it took over 14-weeks to recover to pre-EXMS levels. The reductions in OxPhos were also accompanied by an increased rate of fatigue and indicators of exercise difficulty. These decreases in OxPhos can not be attributed to random fluctuations. Our lab has previously shown that these types of measurements of OxPhos have a test-retest reliability of 5.6% CV and/or an SEP of 0.033 mM/sec. In conclusion, our initial results indicate that our method of measuring OxPhos may be a very specific marker of compromised mitochondria and/or muscle capillary bed function.
