Fig. 1

a Inertial measurement units (IMUs) were placed on the sacrum and the tibia of the right leg. b Acceleration signals in time-domain for trunk and leg segments for one participant for standing on a hard surface with eyes open. c Trunk–leg Magnitude-Squared Coherence (MSC) for iSCI population (red) and able-bodied (AB) individuals (blue) presented as an ensemble average (mean ± standard deviation) for both populations and each standing condition on hard surface (HS) and foam surface (FS) with eyes open (EO) and eyes closed (EC). d Cancellation-index indicating reciprocal action between the angular acceleration of the ankle and hip joints as presented for one participant from AB and iSCI populations for standing on a hard surface with eyes open