A wireless accelerometer node for reliable and valid measurement of lumbar accelerations during treadmill running.

This study investigated the reliability of a wireless accelerometer and its agreement with optical motion capture for the measurement of root mean square (RMS) acceleration during running. RMS acceleration provides a whole-body metric of movement mechanics and economy. Fifteen healthy college-age participants performed treadmill running for two 60-s trials at 2.

Contributions of lower extremity kinematics to trunk accelerations during moderate treadmill running.

Background: Trunk accelerations during running provide useful information about movement economy and injury risk. However, there is a lack of data regarding the key biomechanical contributors to these accelerations. The purpose was to establish the biomechanical variables associated with root mean square (RMS) accelerations of the trunk.

Lower extremity fatigue increases complexity of postural control during a single-legged stance.

Background: Non-linear approaches to assessment of postural control can provide insight that compliment linear approaches. Control entropy (CE) is a recently developed statistical tool from non-linear dynamical systems used to assess the complexity of non-stationary signals. We have previously used CE of high resolution accelerometry in running to show decreased complexity with exhaustive exercise.

Reliability of mechanomyography and triaxial accelerometry in the assessment of balance.

Reliability of high-resolution accelerometery (HRA) and mechanomyography (MMG) was evaluated for the assessment of single-leg balance. Subjects (5M/5F, 25+/-3 yr; 169.4+/-11.

High resolution MEMS accelerometers to estimate VO2 and compare running mechanics between highly trained inter-collegiate and untrained runners.

Background: The purposes of this study were to determine the validity and reliability of high resolution accelerometers (HRA) relative to VO(2) and speed, and compare putative differences in HRA signal between trained (T) and untrained (UT) runners during treadmill locomotion.

Methodology: Runners performed 2 incremental VO(2max) trials while wearing HRA. RMS of high frequency signal from three axes (VT, ML, AP) and the Euclidean resultant (RES) were compared to VO(2) to determine validity and reliability.

Control entropy identifies differential changes in complexity of walking and running gait patterns with increasing speed in highly trained runners.

Regularity statistics have been previously applied to walking gait measures in the hope of gaining insight into the complexity of gait under different conditions and in different populations. Traditional regularity statistics are subject to the requirement of stationarity, a limitation for examining changes in complexity under dynamic conditions such as exhaustive exercise. Using a novel measure, control entropy (CE), applied to triaxial continuous accelerometry, we report changes in complexity of walking and running during increasing speeds up to exhaustion in highly trained runners.

Effects of balance training on selected skills.

The purpose of this study was to determine the effect of a 4-week balance training program on specified functional tasks. Thirty-six subjects (age = 22.7 +/- 2.

Effects of pelvic stabilization on lumbar muscle activity during dynamic exercise.

Many commonly utilized low-back exercise devices offer mechanisms to stabilize the pelvis and to isolate the lumbar spine, but the value of these mechanisms remains unclear. The purpose of this study was to examine the effect of pelvic stabilization on the activity of the lumbar and hip extensor muscles during dynamic back extension exercise. Fifteen volunteers in good general health performed dynamic extension exercise in a seated upright position on a lumbar extension machine with and without pelvic stabilization.

Adaptive sweat gland response after spinal cord injury.

Objective: To compare the eccrine gland cholinergic sensitivity of upper (UE) and lower (LE) extremities in untrained able-bodied individuals (UAB), untrained individuals with spinal cord injury (U/SCI), and trained wheelchair athletes (E/SCI).

Design: Static group comparison.

Setting: SCI population.

Effects of isokinetic ankle fatigue on the maintenance of balance and postural limits.

Objective: To quantify changes in balance parameters and ranges of postural control at the ankle after isokinetic fatigue.

Design: Before-after trials, with a 5 x 6 repeated-measures design.

Setting: General community.