Running mileage, movement mileage, and fitness in male U.S. Navy recruits.

Purpose: The purpose of this study was to determine whether there is a relationship between overall fitness improvement and varying amounts of running and movement mileage.

Methods: Subjects were male U.S.

Correlations between neurograms and locomotor drive potentials in motoneurons during fictive locomotion: implications for the organization of locomotor commands.

The patterns of correlation found between motoneuron pools during fictive locomotion are the same whether the coherence functions used to detect the correlations are determined using pairs of rectified ENGs or motoneuron LDPs and rectified ENGs. This finding suggests that the higher frequencies in rectified ENGs (and, perhaps, EMGs) contain information about the synaptic input to motoneurons. Nevertheless, differences between the coherence functions of rectified ENG pairs and those of LDPs and rectified ENGs suggests that this information is distorted by harmonics introduced by rectification.

Organization of recurrent inhibition and facilitation in motoneuron pools innervating dorsiflexors of the cat hindlimb.

The incidence of recurrent inhibition and facilitation in motor nuclei innervating the dorsiflexors of the ankle and digits was examined in spinalized, decerebrate cats. Motoneurons innervating the anterior and posterior portions of the tibialis anterior (TAa and TAp, respectively) received strong recurrent inhibition following stimulation of either of the homonymous muscle nerves. Both motoneuron species received substantial recurrent inhibition from the semitendinosus (St), but stimulation of the nerve to the extensor digitorum longus (EDL), an ankle flexor synergist, evoked smaller recurrent IPSPs.

Forms of forward quadrupedal locomotion. III. A comparison of posture, hindlimb kinematics, and motor patterns for downslope and level walking.

To gain further insight into the neural mechanisms for different forms of quadrupedal walking, data on postural orientation, hindlimb kinematics, and motor patterns were assessed for four grades of downslope walking, from 25% (14 degrees slope) to 100% (45 degrees), and compared with data from level and downslope walking at five grades (5-25%) on the treadmill (0.6 m/s). Kinematic data were obtained by digitizing ciné film, and electromyograms (EMGs) synchronized with kinematic records were taken from 13 different hindlimb muscles.

Forms of forward quadrupedal locomotion. II. A comparison of posture, hindlimb kinematics, and motor patterns for upslope and level walking.

To gain insight into the neural mechanisms controlling different forms of quadrupedal walking of normal cats, data on postural orientation, hindlimb kinematics, and motor patterns of selected hindlimb muscles were assessed for four grades of upslope walking, from 25 to 100% (45 degrees incline), and compared with similar data for level treadmill walking (0.6 m/s). Kinematic data for the hip, knee, ankle, and metatarsophalangeal joints were obtained from digitizing ciné film that was synchronized with electromyographic (EMG) records from 13 different hindlimb muscles.

Forms of forward quadrupedal locomotion. I. A comparison of posture, hindlimb kinematics, and motor patterns for normal and crouched walking.

1. Posture, hindlimb kinematics, and activity patterns of selected hindlimb muscles were compared for normal and crouched treadmill walking (0.5-0.

Adaptive control for backward quadrupedal walking VI. metatarsophalangeal joint dynamics and motor patterns of digit muscles.

1. We compared the dynamics of the metatarsophalangeal (MTP) joint of the cat's hind paw and the motor patterns of two short and four long muscles of the digits for two walking forms, forward (FWD) and backward (BWD). Kinematic (angular displacements) data digitized from high-speed ciné film and electromyographic (EMG) data were synchronized and assessed for bouts of treadmill walking.