Sex-related sEMG associations during prolonged overground walking depended on muscle, outcome, and processing approach; selected amplitude contrasts (TA and GL peak, GL RMS) persisted on a task-relative scale, but these findings do not establish differences in neural drive, maximal activation capacity, or walking function.
Key Findings
Results
Males had higher tibialis anterior (TA) and gastrocnemius lateralis (GL) peak amplitudes and higher GL RMS than females across all processing variants after Holm correction in the QC-screened dataset.
Processing variants were raw, band-pass-filtered, and filtered features normalized to the peak of each participant-side-muscle ensemble-mean walking envelope.
Mixed-effects models were adjusted for height and body weight.
Analysis used publicly available recordings from 31 healthy adults (19 females, 12 males) comprising 13,465 gait cycles.
Results
Some sex contrasts were present only under specific processing choices.
The TA RMS contrast was significant only in the raw analysis.
A hamstring-region peak contrast was significant only after task-reference normalization.
Results
No muscle-specific integrated EMG (iEMG) comparison survived Holm correction.
iEMG was one of four outcomes evaluated alongside RMS, peak amplitude, and stride-to-stride RMS CV.
Holm correction was applied to multiple comparisons across muscles.
Results
Including the two channels excluded for signal-quality concerns produced limited changes in TA and GL amplitude estimates, whereas stride-to-stride RMS coefficient of variation (CV) findings were sensitive to processing and channel exclusions.
Two channels were excluded from the QC-screened dataset and retained in an inclusive sensitivity analysis.
The amplitude findings were thus comparatively robust to channel inclusion, while CV findings were not.
Methods
The adjusted models included 28 of the 31 participants, contributing 278 and 280 participant-side-muscle summaries in the respective datasets.
Models adjusted for height and body weight, which limited the sample to participants with those covariates.
The unit of analysis was participant-side-muscle summaries.
Conclusions
Sex-related sEMG associations depended on muscle, outcome, and processing approach, and do not establish differences in neural drive, maximal activation capacity, or walking function.
Selected amplitude contrasts persisted on a task-relative scale (normalized to the walking envelope peak).
Surface EMG amplitude is influenced by factors beyond neural drive, so interpretation is limited.
What This Means
This study reanalyzed publicly available muscle-activity recordings (surface electromyography, or sEMG) from 31 healthy adults—19 women and 12 men—walking for a prolonged period. The goal was to see whether leg muscle activity differs between the sexes, and whether the answer changes depending on how the signals are processed.
Men showed higher peak activity in the shin muscle (tibialis anterior) and a calf muscle (gastrocnemius lateralis), and higher average activity in the calf muscle, regardless of how the data were processed. Other differences appeared only under some approaches: one shin-muscle difference showed up only in unfiltered data, and a hamstring-area difference only after signals were scaled to each person's own walking pattern. No differences in total accumulated activity survived statistical correction, and findings on stride-to-stride variability were unstable depending on processing and which channels were included.
This research suggests that sex differences in muscle signals during walking are not uniform and depend heavily on the muscle and analysis choices. The author cautions that these signals do not show differences in how strongly the nervous system drives muscles, in maximal muscle capacity, or in how well people walk. Factors such as tissue under the skin can also influence surface recordings, so the results should be viewed as exploratory in a fairly small sample.
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Celen M. (2026). Sex Differences in Lower-Limb Surface Electromyographic Characteristics During Prolonged Overground Walking.. Physiological research. https://pubmed.ncbi.nlm.nih.gov/42960455/