CONTEXT Researchers have postulated that coactivation of the hamstrings during active knee extension assists the anterior cruciate ligament in maintaining knee joint stability by exerting an opposing force to anterior tibial translation. OBJECTIVE To compare the reciprocal coactivation of the hamstrings while performing low and high velocity isokinetic movements and two closed chain movements...

A plethora of research has examined bilateral and reciprocal concentric strength relationships of the thigh musculature in a variety of athletic populations. However, little research has reported strength values of the trunk and hip musculature. Thus, the purpose of this investigation was to examine concentric and eccentric strength of the trunk and hip flexor and extensor muscle groups in fema...

Methods Apparently healthy resistance trained males (n = 30) were randomized to either a BCAA group or the CHO control group. Participants performed preliminary testing (T1) to derive peak quadriceps isometric torque, peak quadriceps isokinetic torque (60o and 120o per second), and a 1RM barbell back squat. The following week, the participants performed 10x5 repetitions at 80% of their 1RM barb...

The purpose of this study was to compare four different methods of normalising electromyograms (EMGs) recorded during normal gait. Comparisons were made between the amplitude, intra-individual variability and inter-individual variability of EMGs. Surface EMGs were recorded from the biceps femoris, semitendinosus, vastus lateralis and vastus medialis of ten males and two females while they walke...

BACKGROUND When to allow an athlete to return to unrestricted sporting activity after anterior cruciate ligament (ACL) reconstruction remains controversial. PURPOSE To report the results of functional performance testing reported in the literature for individuals at differing time points following ACL reconstruction and to examine differences between graft types. STUDY DESIGN Systematic rev...

Using the Kin-Com (Chattecx Corp, Hixson, TN) isokinetic dynamometer, 20 university females (age = 21.6 ± 1.4 years, wt = 61.73 ± 7.3 kg, ht = 162.81 ± 5.8 cm) performed concentric and eccentric isokinetic contractions at nine different velocities. At each velocity, subjects performed two submaximal and one maximal concentric and eccentric familiarization contractions. Three alternating concent...