Table 4.

Ground contact time, flight time, step length, stride frequency and duty factor for the different groups

Older adults Young adults
Contact time (ms)276±23284±27271±023282±22
Flight time (ms)**80±2583±29112±19104±21
Step length (cm)*,‡93.9±7.699.1±8.499.5±3.0103.6±6.4
Stride frequency (Hz) **1.41±0.101.38±0.131.31±0.081.28±0.07
Duty factor (%)**38.9±3.138.8±3.335.5±2.336.7±2.6
  • Values are means ± S.D. of both legs; N=20 (older runners), N=10 (older non-active subjects), N=9 (younger runners), N=10 (younger non-active subjects).

    Step length was defined as the anterior displacement of the foot (midpoint of the distance between calcaneus and metatarsal markers) from heel strike to contralateral heel strike.

    Asterisks indicate statistically significant differences between older and young adults: *P<0.05, **P<0.01; significant differences between runners and non-active individuals (P<0.05).

    There was no age-by-running activity interaction for the analysed parameters (P>0.05).