Autor: |
Dos Santos PCR; Department of Human Movement Sciences, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. paulocezarr@hotmail.com.; Posture and Gait Studies Laboratory (LEPLO), Institute of Biosciences, Graduate Program in Movement Sciences, São Paulo State University (UNESP), Rio Claro, Brazil. paulocezarr@hotmail.com.; Department of Human Movement Sciences, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands. paulocezarr@hotmail.com., Lamoth CJC; Department of Human Movement Sciences, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands., Barbieri FA; Department of Physical Education, Human Movement Research Laboratory (MOVI-LAB), Graduate Program in Movement Sciences, São Paulo State University (UNESP), Bauru, Brazil., Zijdewind I; Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands., Gobbi LTB; Posture and Gait Studies Laboratory (LEPLO), Institute of Biosciences, Graduate Program in Movement Sciences, São Paulo State University (UNESP), Rio Claro, Brazil., Hortobágyi T; Department of Human Movement Sciences, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. |
Abstrakt: |
We examined the effects of age on intermuscular beta-band (15-35 Hz) coherence during treadmill walking before and after experimentally induced fatigue. Older (n = 12) and younger (n = 12) adults walked on a treadmill at 1.2 m/s for 3 min before and after repetitive sit-to-stand, rSTS, to induce muscle fatigability. We measured stride outcomes and coherence from 100 steps in the dominant leg for the synergistic (biceps femoris (BF)-semitendinosus, rectus femoris (RF)-vastus lateralis (VL), gastrocnemius lateralis (GL)-Soleus (SL), tibialis anterior (TA)-peroneus longus (PL)) and for the antagonistic (RF-BF and TA-GL) muscle pairs at late swing and early stance. Older vs. younger adults had 43-62% lower GL-SL, RF-VL coherence in swing and TA-PL and RF-VL coherence in stance. After rSTS, RF-BF coherence in late swing decreased by ~ 20% and TA-PL increased by 16% independent of age (p = 0.02). Also, GL-SL coherence decreased by ~ 23% and increased by ~ 23% in younger and older, respectively. Age affects the oscillatory coupling between synergistic muscle pairs, delivered presumably via corticospinal tracts, during treadmill walking. Muscle fatigability elicits age-specific changes in the common fluctuations in muscle activity, which could be interpreted as a compensation for muscle fatigability to maintain gait performance. |