Purpose: To characterize and evaluate the repeatability of ultrasound recorded blood flow in the axillary artery during one-arm dynamic elbow flexion.
Method: 11 healthy women (23 +/- 0.9 yr, 168 +/- 1.7 cm, 63 +/- 1.1 kg) performed 90 degrees elbow flexion in supine position. Mean maximum blood velocity was recorded by ultrasound during and after two submaximal loads, representing 16 and 24% of maximal voluntary contraction, and after exhaustion (.VO(2peak))Axillary artery diameter was measured after each workload. Each subject was examined two times 8 wk apart. Oxygen uptake was measured during exercise. Values are mean +/- SE.
Results: Flow was not different in the two tests. Flow was 25% higher immediately after than during exercise at the submaximal workloads. Flow immediately after .VO(2peak) was 1420 +/- 79 mL.min(-1). Axillary artery diameter after .VO(2peak) was 8% larger than at rest. Coefficient of variation ranged from 11 to 23%, coefficient of repeatability ranged from 230 mL.min(-1) at rest to 940 mL.min(-1) after exercise. Coefficient of repeatability for artery diameter was 0.09 cm; coefficient of variation for diameter was about 4% at all recording times.
Conclusion: The present study showed that ultrasound recordings of blood flow during dynamic elbow-flexion exercise were reproducible. The method can be used to study training-induced flow changes and can detect differences of about 130 mL.min(-1). Artery diameter seemed to increase as flow and load increased.