No abstract

Muscle strength and power were impaired at 6 months after ICU discharge and were associated with gait parameters. Future studies are needed to examine the role of muscle strength and power training in post-ICU rehabilitation programs to improve mobility.

The extent to which different locomotor tasks require cognitive control is not well characterized. In this article, the authors consider the potential increase in attentional demands associated with carrying an anterior load while clearing an obstacle. Nine healthy male volunteers participated in 80 walking trials, 20 in each of 4 conditions: 1 no load condition (NL) and 3 carrying conditions (2KG, 5KG, and 10KG). Of the 20 trials in each condition, 12 included a probe reaction time (PRT) test during lead limb obstacle crossing, which was used to measure cognitive load. A load-dependent increase in PRT was observed, with PRT in the 2KG condition being significantly greater than in the NL condition, and PRT in the 5KG and 10KG conditions being significantly greater than in the 2KG condition. These results suggested that cognitive load was increased when: (a) the obstacle was occluded from vision by the load, and (b) the magnitude of load was increased.

Ti t l eEv al u a tio n of t h e eff e c t s of p r e s c ri bi n g g ai t c o m pl exity u si n g s e v e r al fluc t u a ti n g ti mi n g i m p e r a tiv e s

Current research is unclear with respect to whether pole walking (PW) reduces lower limb loading when compared to regular walking (RW). Contradictory findings in the literature may be related to the relative timing between pole and foot contact events, which were examined in the current study among naïve pole walkers. Fourteen young (4 F; 25.3 ± 5.4 years) and 8 older adults (4 F; 68.5 ± 3.2 years) performed PW and RW trials along a force plate embedded walkway at two different visits. The time difference between pole and foot contact during both the onset of ground contact and the peak force application was calculated. Several kinetic measures were calculated for the lower limbs and poles. A significant decrease during PW, compared to RW, was found for foot impulse (2.1%; p < 0.01 ), peak vertical ground reaction force (vGRF) (3.4%; p < 0.01 ), rate of loading (5.2%; p = 0.02 ), and peak push-off vGRF (2.1%; p = 0.01 ). No difference in pole loading was found between age groups and visits. No significant correlations were found between the relative timing and foot loading measures. Significant low-to-moderate negative correlations were found between peak foot and pole vGRFs ( p = 0.04 ), peak foot vGRF and pole strike impulse ( p = 0.01 ), peak foot vGRF and pole impulse ( p = 0.02 ), and peak foot push-off vGRF and pole impulse ( p = 0.01 ), suggesting that as pole loading increased, foot loading decreased. Findings suggest timing between pole and heel contact may not be related to unloading the lower limbs but may be related to other aspects of pole use since PW reduced lower limb loading.

The current study quantified lumbar loading while carrying an anterior load mass and navigating an obstacle. Eight healthy male participants walked down a walkway and crossed an obstacle under three randomised LOAD conditions; empty-box (2 KG), five kilogram (5 KG) and ten kilogram (10 KG). Each walk was assessed at two events: left foot mid-stance (LMS) and right toe-crossing (TC) to characterise any changes from approach to crossing. Measures of interest included: trunk pitch, L4/L5 joint moment, compression, joint anterior-posterior shear and erector spinae activation. Findings demonstrate that obstacle crossing extended posture by 50, 41, 44%, respectively for each carried load magnitude. Further, these results indicate that shear rather than compressive loading may be an important consideration during crossing due to increase by 8, 9, 22% from LMS to TC for each load magnitude tested. These results provide insight into sagittal lumbar loading when navigating an obstacle while carrying a load. Practitioner Summary: The risk of carrying while navigating obstacles on the lumbar spine is not completely understood. The forces at the lumbar spine while simultaneously carrying and obstacle crossing were analysed. Data indicate that carrying and obstacle crossing influence lumbar shear loads, thereby moderately increasing the relative risk at lumbar spine.