Abstract
Resistance training is the most effective strategy to modify muscle architecture,
enhancing sport performance and reducing injury risk. The aim of this study was
to compare the effects of high loads (HL) versus lower loads (LL), maximal
versus submaximal efforts, and high frequency (HF) versus low frequency (LF) on
quadriceps architectural adaptations in team sports players. Five databases were
searched. Vastus lateralis thickness, fascicle length and pennation angle, and
rectus femoris thickness were analyzed as main outcomes. Overall, resistance
training significantly improved muscle thickness and pennation angle, but not
fascicle length. LL led to greater fascicle length adaptations in the vastus
lateralis compared to HL (p=0.01), while no substantial differences were found
for other load comparisons. Degree of effort and training frequency did not show
meaningful differences (p>0.05). In conclusion, LL lengthen the fascicle to a
greater extent than HL, and training with LL twice a week could maximize
architectural adaptations, whereas the degree of effort does not appear to be a
determinant variable on quadriceps architectural adaptations.
Keywords
muscle thickness - fascicle length - pennation angle - strength
