The bilateral limb deficit (BLD) describes the difference in maximal or near maximal force generating capacity of muscles when they are contracted alone or in combination with the contralateral muscles. A deficit occurs when the summed unilateral force is greater than the bilateral force. This study examined the presence of the BLD during isokinetic knee extensions and flexions in a group of adolescent females (n=8, mean of 15+/-1 years) and compared with previously reported data by this researcher of adult and older females. Data were collected from subjects during slow (45 deg/s) isokinetic knee extensions and flexions and it was found that a BLD exists during both extension and flexion regardless of age. Furthermore, this study is the first to examine the presence of the deficit in an adolescent population. Myoelectric signal (MES) data showed that there is no difference between bilateral and unilateral isokinetic knee extensions and flexions regardless of age group.

Fatigue is a common and often debilitating symptom for people living with chronic hepatitis C viral infection. Numerous published reports in the past decade have attempted to address the nature and aetiology of fatigue in chronic hepatitis C; however, this field is plagued with lack of clarity about how hepatitis C virus (HCV)-related fatigue occurs and when it is experienced by the infected person. Consequently, both patients and clinicians alike are unclear about how to mediate or prevent the negative consequences of HCV-related fatigue. In the following article, the authors identify areas of ambiguity and incongruity that have evolved primarily from the underlying assumptions and methodological decisions of researchers in the field of HCV-related fatigue. Research related to fatigue in chronic illness is drawn upon to suggest future directions for investigations and interventions in the field of HCV-related fatigue. Future research needs to move beyond the subjective symptomatology of HCV-related fatigue and begin to account for the multidimensional and contextualised nature of the fatigue experience.

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Previous research identifies that pushing and pulling is responsible for approximately 9–18% of all low back injuries. Additionally, the handle design of a cart being pushed can dramatically alter a worker’s capacity to push (≅9.5%). Surprisingly little research has examined muscle activation of the low back and its role in muscle function. Therefore, the purpose of this study was to examine the effects of handle design combination of pushing a platform truck cart on trunk muscle activity. Twenty participants (10 males and 10 females, mean age = 24.3 ± 4.3 years) pushed 475 lbs using six different handle combinations involving handle orientation (vertical/horizontal/semi-pronated) and handle height (hip/shoulder). Multichannel high-density EMG (HDsEMG) was recorded for left and right rectus abdominis, erector spinae, and external obliques. Pushing at hip height with a horizontal handle orientation design (HH) resulted in significantly less (p < 0.05) muscle activity compared to the majority of other handle designs, as well as a significantly higher entropy than the shoulder handle height involving either the semi-pronated (p = 0.023) or vertical handle orientation (p = 0.028). The current research suggests that the combination of a hip height and horizontal orientation handle design may require increased muscle demand of the trunk and alter the overall muscle heterogeneity and pattern of the muscle activity.