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Fig. 6. Loaded walking. (A) Average curves of the instantaneous recovery of
mechanical energy r(t) for the African women (thick
continuous line, mean of 32 steps by four subjects), the European women (thin
continuous line, mean of 14 steps by five subjects) and all European subjects
(males and females, dotted line, mean of 32 steps by ten subjects). A
comparison with Fig. 4 shows
that, in all subjects, loading decreases tpk- and
increases r(t) at the beginning of the descent of the centre
of mass (ttr,down), but that this results in a net
increase in Rint in the African women only (final value
attained by the thick line at the end of the step in B). The corresponding
mean values of the parameters for all European subjects and the African women
are given in Table 1 (loaded).
For further details, see legend to Fig.
4.