The effect of aerobic exercise on quadriceps echo intensity and cross-sectional area

Abstract

The two primary measurements involving Ultrasound Imaging used to assess changes in muscle following exercise are Echo Intensity (EI), which is the gray scale of the image and cross-sectional area (CSA). Due to limited literature, it is unclear how and to what degree muscles composition changes following aerobic exercise.
Purpose: This study evaluated the change in CSA and EI following aerobic cycling exercise.
Methods: Sixteen males (age: 24 ± 7, height 184 ± 6 cm, mass 80 ± 7 kg) voluntarily cycled for 60 minutes, Pre and post EI and CSA of the Rectus Femoris (RF) and Vastus Lateralis (VL) were measured using US.
Results: There was a statistically significant (P<0.01) increase in EI in the RF 34.30to 38.0 A.U. and the VL 27.74 to 32.11 A.U., but there was no significant difference in CSA.
Conclusions: Aerobic exercise does influence EI but not CSA during aerobic exercise.