Université de Fribourg

Lower between-limb asymmetry during running on treadmill compared to overground in subjects with laterally pronounced knee osteoarthritis

Robadey, Jacques ; Staudenmann, Didier ; Schween, Raphael ; Gehring, Dominic ; Gollhofer, Albert ; Taube, Wolfgang

In: PLOS ONE, 2018, vol. 13, no. 10, p. e0205191

Subjects with knee osteoarthritis (KOA) show gait asymmetries evidenced by lower knee flexion and shorter contact times for the affected leg. Interestingly, running on a treadmill compared to running overground is also associated with lower knee flexion and shorter contact times. Thus, it is of particular interest how gait patterns are influenced by the type of ground in subjects with KOA....

Université de Fribourg

Brachialis muscle activity can be assessed with surface electromyography

Staudenmann, Didier ; Taube, Wolfgang

In: Journal of Electromyography and Kinesiology, 2015, vol. 25, no. 2, p. 199–204

The brachialis muscle (BR) represents an important elbow flexor and its activity has so far mainly been measured with intramuscular electromyography (EMG). The aim of this study was to examine whether the activity of the BR can be assessed with surface EMG without interference from the biceps brachii (BB). With eight subjects we measured surface EMG of the arm flexor synergists, BR, BB, and...

Université de Fribourg

Increase in heterogeneity of biceps brachii activation during isometric submaximal fatiguing contractions: a multichannel surface EMG study

Staudenmann, Didier ; Dieën, Jaap H. van ; Stegeman, Dick F. ; Enoka, Roger M.

In: Journal of Neurophysiology, 2014, vol. 111, no. 5, p. 984–990

The effects of fatigue emerge from the beginning of sustained submaximal contractions, as shown by an increase in the amplitude of the surface electromyogram (EMG). The increase in EMG amplitude is attributed to an augmentation of the excitatory drive to the motor neuron pool that, more importantly than increasing discharge rates, recruits additional motor units for the contraction. The aim of...

Université de Fribourg

Redundancy or heterogeneity in the electric activity of the biceps brachii muscle? Added value of PCA-processed multi-channel EMG muscle activation estimates in a parallel-fibered muscle

Staudenmann, Didier ; Stegeman, Dick F. ; Dieën, Jaap H. van

In: Journal of Electromyography and Kinesiology, 2013, p. -

Conventional bipolar EMG provides imprecise muscle activation estimates due to possibly heterogeneous activity within muscles and due to improper alignment of the electrodes with the muscle fibers. Principal component analysis (PCA), applied on multi-channel monopolar EMG yielded substantial improvements in muscle activation estimates in pennate muscles. We investigated the degree of...