Early emergence of temporal co-ordination of lower limb segments elevationangles in human locomotion

We analysed the co-ordination of the elevation angles of the thigh (alpha ( t)), shank (alpha (s)) and foot (alpha (f)) during walking in 19 adults and 21 children (aged 11-144 months), including the very first unsupported ste ps in four. Cross-correlation functions (CCF) maturation of pairs of elevat ion angles was quantified by a global error parameter (Et-(CCF)) reflecting the difference between particular CCF value of toddlers and mean adult val ue (Ea((CCF))). During the very first step, E4((CCF)) could be five times h igher than Ea((CCF)) With walking experience, Et-(CCF) for both alpha (t)-a lpha (s) and alpha (s)-alpha (f) pairs evolved following a biexponential pr ofile, with a fast time constant below 6 months. Adult-like CCF parameters were reached earlier for alpha (s)-alpha (f) than alpha (f)-alpha (s) indic ating disto-proximal maturation of the temporal co-ordination of the lower limb segments in human locomotion. (C) 2001 Elsevier Science Ireland Ltd. A ll rights reserved.