Prediction of transition speed in gaits based on kinetics and kinematics variables

Abstract

The kinetic and kinematic aspects of walking and running are very different at their preferred speed. Locomotion at gait transitions is rarely used; hence actual alternation across the transition speed (TS) remains an unexploited area that can potentially merit run/walk in race running. Awareness of the scientific knowledge in gait transition should therefore be valuable. The aim of this thesis was to investigate the gait transition phenomena and predict the transition speed on different gradients based on the oxygen uptake kinetics and lower limb kinematics. The study investigated preferred transition speed (PTS) on different gradient inclinations and was completed in three stages; firstly laboratory experiments TS1 and TS2 determined the actual PTS, subsequent experiments (TS3 and TS4) examined changes of the oxygen kinetics across PTS. The third stage, TS5 used the kinematics data collected to propose mathematical models that examined the PTS. An overall total of seventy-nine participants (48 males and 31 females) were involved at different stages and rigorously undergo the separate experimental protocols. The findings support as well as contradict previous literature results. Firstly, the energy equivalent TS (EETS) based on kinetics of oxygen uptake per unit distance (EETS/km) and per unit stride (EETS/stride) accurately predicted the PTS on the flat but not on other gradients. Secondly, the increased ankle muscular constraint conditions of using weights did not affect the PTS. However, it significantly increased the oxygen uptake kinetics for run/walk on – 8 and 0 % and the Bla on the + 8 %. Based on novelty of the mathematical model, the role of the dorsi and plantar flexors was further evidenced to influence and predict PTS regardless of gradient inclinations. In conclusion, the findings in this thesis indicated that different metabolic energy pathways regulated the run/walk and that ankle muscular constraints determined the PTS. Incorporating the synergistic perspective, cognitive influence plays an important role to overcoming difficulty of walking at running speeds as observed in the occurrence of hysteresis in TS1. Information on the run/walk can be integrated during training and race as recommended from the thesis findings.