title: Increasing preferred step rate during running reduces plantar pressures.
abstract: Increasing preferred step rate during running is a commonly used strategy in the management of running-related injuries. This study investigated the effect of different step rates on plantar pressures during running. Thirty-two healthy runners ran at a comfortable speed on a treadmill at five step rates (preferred, ±5%, and ±10%). For each step rate, plantar pressure data were collected using the pedar-X in-shoe system. Compared to running with a preferred step rate, a 10% increase in step rate significantly reduced peak pressure (144.5±46.5 vs 129.3±51 kPa; P=.033) and maximum force (382.3±157.6 vs 334.0±159.8 N; P=.021) at the rearfoot, and reduced maximum force (426.4±130.4 vs 400.0±116.6 N; P=.001) at the midfoot. In contrast, a 10% decrease in step rate significantly increased peak pressure (144.5±46.5 vs 161.5±49.3 kPa; P=.011) and maximum force (382.3±157.6 vs 425.4±155.3 N; P=.032) at the rearfoot. Changing step rate by 5% provided no effect on plantar pressures, and no differences in plantar pressures were observed at the medial forefoot, lateral forefoot or hallux between the step rates. This study's findings indicate that increasing preferred step rate by 10% during running will reduce plantar pressures at the rearfoot and midfoot, while decreasing step rate by 10% will increase plantar pressures at the rearfoot. However, changing preferred step rate by 5% will provide no effect on plantar pressures, and forefoot pressures are unaffected by changes in step rate.
authors.affiliation: Discipline of Podiatry, School of Allied Health, La Trobe University, Melbourne, Vic., Australia.
authors.forename: James M
authors.initials: JM
authors.lastname: Gerrard
authors.affiliation: Discipline of Podiatry, School of Allied Health, La Trobe University, Melbourne, Vic., Australia.|La Trobe Sport and Exercise Medicine Research Centre, School of Allied Health, La Trobe University, Melbourne, Vic., Australia.
authors.forename: Daniel R
authors.identifier: http://orcid.org/0000-0002-0825-0608
authors.initials: DR
authors.lastname: Bonanno
mesh_terms: D000328:Adult; D005260:Female; D005528:Foot / Q000502:physiology*; D005684:Gait; D006801:Humans; D008297:Male; D008875:Middle Aged; D011312:Pressure; D012420:Running / Q000502:physiology*; D055815:Young Adult
keywords: kinetics; plantar loading; running cadence; step frequency