Inter-segment foot kinematics during cross-slope running (original) (raw)
Locomotor adaptations for changes in the slope of the walking surface
Gait & Posture, 2004
The goal of this study was to examine the transition of walking from a level surface onto different inclined surfaces. Kinematic data of limb and trunk segments were recorded from individuals as they approached and stepped onto four different ramped surfaces (slopes = 3 • , 6 • , 9 • , 12 •). This transition introduced significant adaptations to the swing limb trajectory that were evident in even the lowest ramp condition and appear to be scaled to the ramp inclination although the nature of this scaling seemed to change between the 6 • and 9 • conditions. An increased forward pitch of the trunk orientation during all ramp conditions was initiated early on during the preceding stance phase on level ground. The swing limb modification essentially consisted of a two-stage response. The initial response of the limb trajectory changes was not specific to the degree of inclination but later changes were dependent on the ramp condition. The initial response is to ensure a safe toe clearance as the foot approaches the edge of the ramp and then later modifications provide the appropriate positioning of the limb to prepare for an elevated foot contact. Early changes were actively produced through an increased pull-off by the hip flexors and an elevation of the swing limb by the active muscle control of the stance limb. Ankle dorsiflexion also appears to have a supporting role increasing toe clearance. Absorption at the hip and knee during later swing contribute to control and position the limb in preparation for foot contact. These strategies were similar to those adopted for step changes in the level of the walking surface where there are similar demands of the quickly moving the limb forward and upward, however, the positioning of the limb for new angled landing surface requires further adaptations.
Journal of Biomechanics, 2018
Knowing the ground reaction forces (GRFs) during walking has various biomechanical applications in injury prevention, gait analysis, as well as prosthetic and footwear design. The current study presents a method for predicting the GRFs in level and incline/decline walking that may be used in various outdoor biomechanics studies geared towards the above applications. The method was developed to predict the complete set of GRFs at walking inclinations of 0°, ±5°, ±10°, ±15°, and ±20°. Plantar pressure insoles were used to obtain inclination-specific, linear regression models based on three periods of gait stance phase, and the model-determined GRFs were compared with those measured from a forceplate. The three periods were determined based on the observed shifting of load-bearing insole sensors from heel to forefoot during walking, i.e., heel-strike, midstance, and toe-off. Six subjects wearing minimalist shoes fitted with plantar pressure insoles containing 99 pressure sensors performed ten walking trials at each of the aforementioned inclinations on an adjustable ramp with an embedded forceplate. Data from contact of the instrumented shoes with the forceplate were used to create linear regressions to transform insole pressure data into a complete set of GRFs. The root mean square error (RMSE) over peak recorded values were on average 10%, 3%, 21% for level walking and 11%, 4%, 23% for ramp walking in the respective anteroposterior, vertical, and mediolateral directions. The multistage linear regression model developed in the current study may be an acceptable option for estimating GRFs during walking in various environments without the restraint of a forceplate.
Footstep analysis at different slopes and speeds in elite race walking
Journal of strength and conditioning research / National Strength & Conditioning Association, 2013
Padulo, J, Annino, G, D'Ottavio, S, Vernillo, G, Smith, L, Migliaccio, GM, and Tihanyi, J. Footstep analysis at different slopes and speeds in elite race walking. J Strength Cond Res XX(X): 000-000, 2012-To investigate the effects of speed and slope on kinematic parameters, we studied the step parameters of 12 elite race walkers on a treadmill at different speeds (3.61, 3.89, and 4.17 mÁs 21 ) and slopes (0, 2, and 7%). A high-speed digital camera (210 Hz) was used to record motion, and 2D data were analyzed with Dartfish 5.5Pro. The parameters studied were step length (SL), step frequency (SF), and contact time (CT). The results showed that the increases in SL were linearly related to increases in speed: r = 0.37 with p , 0.01, whereas decreases in SL were elicited with an increase in slope r = -0.56, p , 0.0001 ([0-2% = -3.5%, p , 0.02], [0-7% = -7.5%, p , 0.01]). The SF was positively correlated with increases in speed, r = 0.56, p = 0.0001, and slopes, r = 0.50, p , 0.0001 (0-2% = 3.6% n.s.; 0-7% = 8.5%, p , 0.01). Conversely, CT was negatively correlated with increases of both speed; r = -0.57, p , 0.0001 and slope r = -0.50, p , 0.0001 (0-2% = -3.4%, n.s.; 0-7% = -7.7%, p , 0.01). These results suggest that using slopes ,7% could considerably alter the neuromechanical behavior of athletes, whereas slopes around 2% could positively influence the performance of the elite race walkers without altering the race-walking technique.
Effect of slope and footwear on running economy and kinematics
Scandinavian Journal of Medicine & Science in Sports, 2013
Lower energy cost of running (Cr) has been reported when wearing minimal (MS) vs traditional shoes (TS) on level terrain, but the effect of slope on this difference is unknown. The aim of this study was to compare Cr, physiological, and kinematic variables from running in MS and TS on different slope conditions. Fourteen men (23.4 Ϯ 4.4 years; 177.5 Ϯ 5.2 cm; 69.5 Ϯ 5.3 kg) ran 14 5-min trials in a randomized sequence at 10 km/h on a treadmill. Subjects ran once wearing MS and once wearing TS on seven slopes, from-8% to +8%. We found that Cr increased with slope gradient (P < 0.01) and was on average 1.3% lower in MS than TS (P < 0.01). However, slope did not influence the Cr difference between MS and TS. In MS, contact times were lower (P < 0.01), flight times (P = 0.01) and step frequencies (P = 0.02) were greater at most slope gradients, and plantar-foot angles-and often ankle plantar-flexion (P = 0.01)-were greater (P < 0.01). The 1.3% difference between footwear identified here most likely stemmed from the difference in shoe mass considering that the Cr difference was independent of slope gradient and that the between-footwear kinematic alterations with slope provided limited explanations.
Quantifying Kinematic Adaptations of Gait During Walking on Terrains of Varying Surface Compliance
2020 8th IEEE RAS/EMBS International Conference for Biomedical Robotics and Biomechatronics (BioRob), 2020
Locomotion is essential for a person’s ability to function in society. When an individual has a condition that limits locomotion, such as a lower limb amputation, the performance of a prosthetic often determines the quality of life an individual regains. In recent years, powered prosthetic devices have shown nearly identical replication for human leg motion on non-compliant terrains. However, they still face numerous functional deficits such as increased metabolic cost and instability for walking on surfaces of varying compliance and complexity. This paper proposes joint angles of the biological leg are uniquely altered by surface compliance regardless of a subject’s individual walking pattern. These differences are then displayed and quantified as a way to better characterize able-bodied walking compensation typical with three common terrains: sand, grass and gravel. This study also collects data outdoors using IMU sensors and is not limited by lab setup and conditions. These resul...
Gait & Posture, 2020
Background: The Oxford Foot Model (OFM) and Rizzoli Foot Model (RFM) are the two most frequently used multi-segment models to measure foot kinematics. However, a comprehensive comparison of the kinematic output of these models is lacking. Research question: What are the differences in kinematic output between OFM and RFM during normal gait and typical pathological gait patterns in healthy adults?. Methods: A combined OFM and RFM marker set was placed on the right foot of ten healthy subjects. A static standing trial and six level walking trials were collected for normal gait and for four voluntarily adopted gait types: equinus, crouch, toe-in and toe-out. Joint angles were calculated for every trial for the hindfoot relative to shank (HF-SH), forefoot relative to hindfoot (FF-HF) and hallux relative to forefoot (HX-FF). Average static joint angles of both models were compared between models. After subtracting these offsets, the remaining dynamic angles were compared using statistical parametric mapping repeated measures ANOVAs and t-tests. Furthermore, range of motion was compared between models for every angle. Results: For the static posture, RFM compared to OFM measured more plantar flexion (Δ = 6 • ) and internal rotation (Δ = 7 • ) for HF-SH, more plantar flexion (Δ = 34 • ) and inversion (Δ = 13 • ) for FF-HF and more dorsal flexion (Δ = 37 • ) and abduction (Δ = 12 • ) for HX-FF. During normal walking, kinematic differences were found in various parts of the gait cycle. Moreover, range of motion was larger in the HF-SH for OFM and in FF-HF and HX-FF for RFM. The differences between models were not the same for all gait types. Equinus and toe-out gait demonstrated most pronounced differences. Significance: Differences are present in kinematic output between OFM and RFM, which also depend on gait type. Therefore, kinematic output of foot and ankle studies should be interpreted with careful consideration of the multi-segment foot model used.