MUSCLE OXYGENATION AND FEMORAL ARTERY FLOW DURING DYNAMIC PLANTAR FLEXION EXERCISE

Abstract

1173 Purpose of the study was to investigate oxygenation patterns of m. gastrocnemius, a. tibialis and 1. soleus muscle groups and common femoral artery blood flow (Qfa) during dynamic plantar flexion exercise at different contraction frequency. Six females (21±1% y.o.) in a supine position performed a 1-min dynamic plantar flexion at 30% MVC (40, 60, 80 cpm) alternated with a 15-min recovery. Then they exercised (60 cpm) until exhaustion. Qfa in the dominant leg was measured by Doppler ultrasound (HP Sonos 1000). Muscle oxygenation (mSO2) was measured by a near-infrared photometer based on spatially resolved method (OM-100AS, Shimadzu). Qfa almost doubled after the onset of exercise reaching a plateau within 30 s independently of contraction frequency. L. soleus and a. tibialis mSO2 sligthly decreased only at 80 cpm. Whilst m. gastrocnemius mSO2 reached its minimum value since the beginning of exercise at 40 cpm (from 71±3 to 29±8 at 40 cpm; from 72±2 to 29±9 at 60 cpm; from 73±2 to 29±8 at 80 cpm). At 60 cpm Qfa progressively increased throughout the duration of exhaustive exercise, whilst m. gastrocnemius mSO2 dropped at the onset of exercise and gradually recovered during the last part of exercise. These data suggest that oxygenation pattern differs in main synergists for plantar flexion at different cpm and m. gastrocnemius mSO2 recovery during exhaustive exercise is an indirect evidence of regional blood flow redistribution in the calf muscles. Supported by CNR and JSPS Exchange Program