The purposes of this investigation were to determine the effects of 8 weeks of unilateral concentric-only dynamic constant-external-resistance (DCER) training on the cross-sectional area (CSA) and strength of the trained and contralateral quadriceps femoris muscles. Seventeen men (ages 24.5 ± 4.6 yrs) volunteered for the study and were divided into a training (Tr) group and a control (Con) group. The Tr group trained the nondominant limb with concentric-only leg extension DCER exercise 3 times a week for 8 weeks. Pretraining and posttraining CSA and strength measurements for both the trained and contralateral limbs were determined for all subjects through magnetic resonance imaging scans and concentric DCER strength tests, respectively. The results indicated a significant (p < 0.05) 3.3% mean increase in the CSA of the trained quadriceps femoris muscles, and significant increases in the concentric DCER strength of both the trained (39.7%) and contralateral (14.6%) limbs. These data suggest neural adaptations.
- Muscle size
- Strength training
ASJC Scopus subject areas
- Orthopedics and Sports Medicine
- Physical Therapy, Sports Therapy and Rehabilitation