Developing new intermuscular coordination patterns through an electromyographic signal-guided training in the upper extremity.
Gang Seo, Jeong-Ho Park, Hyung-Soon Park and 1 others
PMID 37658406WHAT IT FOUND
Ten healthy adults trained six weeks with EMG biofeedback learned to separate brachioradialis and biceps activation and use new upper-limb muscle coordination patterns when asked to use the trained strategy.
Habitual patterns did not change.
Key findings
01During the six-week training, task performance improved for trials that targeted biceps activation while suppressing brachioradialis.
02From Week 2, the trained-strategy synergy set changed: brachioradialis joined the shoulder adductor/flexor pattern, and biceps formed a biceps-dominant elbow flexor pattern.
03The habitual synergy set was conserved, and the estimated number of synergies stayed at five.
STILL TO COME
How it was doneWhat they foundWhat it means for PTs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study was done in 10 young adults with no neurological or musculoskeletal injury, so it does not show what happens in patients with stroke or other motor impairments. There was no control group, so the observed changes cannot be compared with what might have happened without training or with repeated testing. The study did not include a retention test after the six-week training period, so it does not show whether the new patterns persisted after training stopped. Outcomes were muscle activity and synergy patterns, not upper-limb function or activities of daily living. The muscle synergy result depends on electrode placement, posture, and the selected muscles, although the study used custom shirts, posture checks, and a harness. Ten of 12 prescreened individuals could not separate the two muscles with verbal guidance, and only those 10 were enrolled.
The easy way to misread this
Do not read this as evidence that EMG-guided training improves upper-limb function after stroke. The study tested ten healthy adults, measured muscle coordination patterns, did not include patients, did not include a control group, and did not assess activities of daily living.