The influence of cognitive load on metabolic cost of transport during overground walking in healthy, young adults

Preferred walking speed (PWS) is considered a robust measure for assessing mobility and overall health. Healthy reference data are unavailable for Qatar. The aim of this study was to investigate PWS and underlying gait parameters around PWS among healthy young adults living in Qatar. PWS was assessed for 18 Qataris (9 females) and 16 non-Qatari Arabs residing in Qatar (9 females). Within- and between-gender group comparisons were carried out using Mann–Whitney U-tests. Metabolic cost of transport, heart rate, rating of perceived exertion, and spatiotemporal parameters were compared between Qatari and non-Qatari groups of similar gender at seven speed levels relative to PWS using two-way analyses of variance (ANOVAs). Similar comparisons were done at two absolute speeds using Mann–Whitney U-tests. While PWS did not differ significantly between the female groups, it was on average 19% slower for the Qatari males as compared to non-Qatari males. At similar relative speeds, differences appeared solely in physiological parameters between female groups. Only spatiotemporal differences were revealed between the male groups where longer stride and support phase durations and slower stride frequencies characterized the Qatari male group. It is suggested that differences in PWS could be due to potential cultural factors (e.g., cultural clothing) differentiating the Qatari and non-Qatari groups. PWS values reported in this study also appear systematically lower when compared to Western references found in the literature. Findings suggest that the assessment of normative gait values needs to take both cultural habits and geographic disparity into account.

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Quantifying Cause-Effect Relations Between Walking Speed, Propulsive Force, and Metabolic Cost

10.1101/2021.10.18.21265129 ◽

2021 ◽

Author(s):

Richard Pimentel ◽

Jordan N Feldman ◽

Michael D Lewek ◽

Jason R Franz

Keyword(s):

Young Adults ◽

Health Status ◽

Time Course ◽

Walking Speed ◽

Metabolic Cost ◽

Propulsive Force ◽

Metabolic Power ◽

Cost Of Transport ◽

Walking Speeds ◽

Variance Explained

Walking speed is a useful surrogate for health status across the population. Walking speed appears to be governed in part by propulsive force (FP) generated during push-off and simultaneously optimized to minimize metabolic cost. However, no study to our knowledge has established empirical cause-effect relations between FP, walking speed, and metabolic cost, even in young adults. To overcome the potential linkage between these factors, we used a self-paced treadmill controller and real-time biofeedback to independently prescribe walking speed or FP across a range of condition intensities. Walking with larger and smaller FP led to instinctively faster and slower walking speeds, respectively, with about 80% of variance explained between those outcomes. We also found that comparable changes in either FP or walking speed elicited predictable and relatively uniform changes in metabolic cost, each explaining about ~53% of the variance in net metabolic power and ~15% of the variance in cost of transport, respectively. These findings build confidence that interventions designed to increase FP will translate to improved walking speed. Repeating this protocol in other populations may identify additional cause-effect relations that could inform the time course of gait decline due to age and disease.

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Metabolic cost in healthy fit older adults and young adults during overground and treadmill walking

European Journal of Applied Physiology ◽

10.1007/s00421-021-04740-2 ◽

2021 ◽

Author(s):

Sauvik Das Gupta ◽

Maarten Bobbert ◽

Herre Faber ◽

Dinant Kistemaker

Keyword(s):

Older Adults ◽

Young Adults ◽

Walking Speed ◽

Metabolic Cost ◽

Treadmill Walking ◽

Afternoon Session ◽

Overground Walking ◽

Age Related ◽

Long Time ◽

Per Se

Abstract Purpose The purpose of this study was to determine whether net metabolic cost of walking is affected by age per se. Methods We selected 10 healthy, active older adults (mean age 75 years) and 10 young adults (mean age 26 years), and determined their preferred overground walking speed. On the same day, in a morning and afternoon session, we had them walk at that speed overground and on a treadmill while we measured oxygen consumption rate. From the latter we subtracted the rate in sitting and calculated net metabolic cost. Results Anthropometrics were not different between the groups nor was preferred walking speed (1.27 m s−1 both groups). There was no difference in net metabolic cost of overground walking between older and young adults (e.g., in the morning 2.64 and 2.56 J kg−1 m−1, respectively, p > 0.05). In the morning session, net metabolic cost of walking was higher on the treadmill than overground in our older adults by 0.6 J kg−1 m−1 (p < 0.05), but not in young adults. Conclusion First, there is no effect of age per se on metabolic cost of overground walking. Second, older adults tend to have higher metabolic cost of walking on a treadmill than walking overground at preferred speed, and adaptation may take a long time. The commonly reported age-related elevation of metabolic cost of walking may be due to confounding factors causing preferred walking speed to be lower in older adults, and/or due to older adults reacting differently to treadmill walking than young adults.

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The immediate effect of foot orthoses on gluteal and lower limb muscle activity during overground walking in healthy young adults

Gait & Posture ◽

10.1016/j.gaitpost.2021.07.003 ◽

2021 ◽

Vol 89 ◽

pp. 102-108

Author(s):

Adam I. Semciw ◽

Viji N. Visvalingam ◽

Charlotte Ganderton ◽

Peter Lawrenson ◽

Paul W. Hodges ◽

...

Keyword(s):

Young Adults ◽

Lower Limb ◽

Muscle Activity ◽

Foot Orthoses ◽

Lower Limb Muscle ◽

Limb Muscle ◽

Overground Walking

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Associations Between Foot Placement Asymmetries and Metabolic Cost of Transport in Hemiparetic Gait

Neurorehabilitation and Neural Repair ◽

10.1177/1545968316675428 ◽

2016 ◽

Vol 31 (2) ◽

pp. 168-177 ◽

Cited By ~ 17

Author(s):

James M. Finley ◽

Amy J. Bastian

Keyword(s):

Walking Speed ◽

Metabolic Cost ◽

Positive Association ◽

Stroke Survivor ◽

Gas Analysis ◽

Stroke Survivors ◽

Cost Of Transport ◽

Foot Placement ◽

Hemiparetic Gait ◽

All Speeds

Stroke survivors often have a slow, asymmetric walking pattern. They also walk with a higher metabolic cost than healthy, age-matched controls. It is often assumed that spatial-temporal asymmetries contribute to the increased metabolic cost of walking poststroke. However, elucidating this relationship is made challenging because of the interdependence between spatial-temporal asymmetries, walking speed, and metabolic cost. Here, we address these potential confounds by measuring speed-dependent changes in metabolic cost and implementing a recently developed approach to dissociate spatial versus temporal contributions to asymmetry in a sample of stroke survivors. We used expired gas analysis to compute the metabolic cost of transport (CoT) for each participant at 4 different walking speeds: self-selected speed, 80% and 120% of their self-selected speed, and their fastest comfortable speed. We also computed CoT for a sample of age- and gender-matched control participants who walked at the same speeds as their matched stroke survivor. Kinematic data were used to compute the magnitude of a number of variables characterizing spatial-temporal asymmetries. Across all speeds, stroke survivors had a higher CoT than controls. We also found that our sample of stroke survivors did not choose a self-selected speed that minimized CoT, contrary to typical observations in healthy controls. Multiple regression analyses revealed negative associations between speed and CoT and a positive association between asymmetries in foot placement relative to the trunk and CoT. These findings suggest that interventions designed to increase self-selected walking speed and reduce foot-placement asymmetries may be ideal for improving walking economy poststroke.

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Energy Expenditure of Level Overground Walking in Young Adults: Comparison With Prediction Equations

Journal of Physical Activity and Health ◽

10.1123/jpah.2020-0283 ◽

2021 ◽

pp. 1-8

Author(s):

Jingjing Xue ◽

Shuo Li ◽

Rou Wen ◽

Ping Hong

Keyword(s):

Young Adults ◽

Energy Expenditure ◽

Metabolic Rate ◽

Energy Cost ◽

Sports Medicine ◽

Resting Metabolic Rate ◽

Prediction Equations ◽

Overground Walking ◽

All Speeds ◽

Walking Energy Cost

Background: The purpose of this study was to investigate the accuracy of the published prediction equations for determining level overground walking energy cost in young adults. Methods: In total, 148 healthy young adults volunteered to participate in this study. Resting metabolic rate and energy expenditure variables at speeds of 4, 5, and 6 km/h were measured by indirect calorimetry, walking energy expenditure was estimated by 3 published equations. Results: The gross and net metabolic rate per mile of level overground walking increased with increased speed (all P < .01). Females were less economical than males. The present findings revealed that the American College of Sports Medicine and Pandolf et al equations significantly underestimated the energy cost of overground walking at all speeds (all P < .01) in young adults. The percentage mean bias for American College of Sports Medicine, Pandolf et al, and Weyand et al was 12.4%, 16.8%, 1.4% (4 km/h); 21.6%, 15.8%, 7.1% (5 km/h); and 27.6%, 12%, 6.6% (6 km/h). Bland–Altman plots and prediction error analysis showed that the Weyand et al was the most accurate in 3 existing equations. Conclusions: The Weyand et al equation appears to be the most suitable for the prediction of overground walking energy expenditure in young adults.

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Muscle Metabolic Energy Costs While Modifying Propulsive Force Generation During Walking

10.1101/2020.07.31.230698 ◽

2020 ◽

Author(s):

Richard E. Pimentel ◽

Noah L. Pieper ◽

William H. Clark ◽

Jason R. Franz

Keyword(s):

Young Adults ◽

Metabolic Cost ◽

Metabolic Energy ◽

Energy Costs ◽

Joint Power ◽

Lower Limb Muscles ◽

Age Related ◽

Musculoskeletal Models ◽

Metabolic Costs ◽

Related Increase

AbstractWe pose that an age-related increase in the metabolic cost of walking arises in part from a redistribution of joint power where muscles spanning the hip compensate for insufficient ankle push-off and smaller peak propulsive forces (FP). Young adults elicit a similar redistribution when walking with smaller FP via biofeedback. We used targeted FP biofeedback and musculoskeletal models to estimate the metabolic costs of operating lower limb muscles in young adults walking across a range of FP. Our simulations support the theory of distal-to-proximal redistribution of joint power as a determinant of increased metabolic cost in older adults during walking.

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Factors affecting metabolic cost of transport during a multi-stage running race

Journal of Experimental Biology ◽

10.1242/jeb.091645 ◽

2013 ◽

Vol 217 (5) ◽

pp. 787-795 ◽

Cited By ~ 17

Author(s):

S. Lazzer ◽

P. Taboga ◽

D. Salvadego ◽

E. Rejc ◽

B. Simunic ◽

...

Keyword(s):

Metabolic Cost ◽

Cost Of Transport ◽

Factors Affecting ◽

Multi Stage

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Reduced prosthetic stiffness lowers the metabolic cost of running for athletes with bilateral transtibial amputations

Journal of Applied Physiology ◽

10.1152/japplphysiol.00587.2016 ◽

2017 ◽

Vol 122 (4) ◽

pp. 976-984 ◽

Cited By ~ 10

Author(s):

Owen N. Beck ◽

Paolo Taboga ◽

Alena M. Grabowski

Keyword(s):

Lower Limb ◽

Metabolic Cost ◽

Ground Reaction Forces ◽

Metabolic Rates ◽

Distance Running ◽

Cost Of Transport ◽

Leg Stiffness ◽

Metabolic Costs ◽

In Series ◽

Reaction Forces

Inspired by the springlike action of biological legs, running-specific prostheses are designed to enable athletes with lower-limb amputations to run. However, manufacturer’s recommendations for prosthetic stiffness and height may not optimize running performance. Therefore, we investigated the effects of using different prosthetic configurations on the metabolic cost and biomechanics of running. Five athletes with bilateral transtibial amputations each performed 15 trials on a force-measuring treadmill at 2.5 or 3.0 m/s. Athletes ran using each of 3 different prosthetic models (Freedom Innovations Catapult FX6, Össur Flex-Run, and Ottobock 1E90 Sprinter) with 5 combinations of stiffness categories (manufacturer’s recommended and ± 1) and heights (International Paralympic Committee’s maximum competition height and ± 2 cm) while we measured metabolic rates and ground reaction forces. Overall, prosthetic stiffness [fixed effect (β) = 0.036; P = 0.008] but not height ( P ≥ 0.089) affected the net metabolic cost of transport; less stiff prostheses reduced metabolic cost. While controlling for prosthetic stiffness (in kilonewtons per meter), using the Flex-Run (β = −0.139; P = 0.044) and 1E90 Sprinter prostheses (β = −0.176; P = 0.009) reduced net metabolic costs by 4.3–4.9% compared with using the Catapult prostheses. The metabolic cost of running improved when athletes used prosthetic configurations that decreased peak horizontal braking ground reaction forces (β = 2.786; P = 0.001), stride frequencies (β = 0.911; P < 0.001), and leg stiffness values (β = 0.053; P = 0.009). Remarkably, athletes did not maintain overall leg stiffness across prosthetic stiffness conditions. Rather, the in-series prosthetic stiffness governed overall leg stiffness. The metabolic cost of running in athletes with bilateral transtibial amputations is influenced by prosthetic model and stiffness but not height. NEW & NOTEWORTHY We measured the metabolic rates and biomechanics of five athletes with bilateral transtibial amputations while running with different prosthetic configurations. The metabolic cost of running for these athletes is minimized by using an optimal prosthetic model and reducing prosthetic stiffness. The metabolic cost of running was independent of prosthetic height, suggesting that longer legs are not advantageous for distance running. Moreover, the in-series prosthetic stiffness governs the leg stiffness of athletes with bilateral leg amputations.

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Contributions of metabolic and temporal costs to human gait selection

Journal of The Royal Society Interface ◽

10.1098/rsif.2018.0197 ◽

2018 ◽

Vol 15 (143) ◽

pp. 20180197 ◽

Cited By ~ 8

Author(s):

Erik M. Summerside ◽

Rodger Kram ◽

Alaa A. Ahmed

Keyword(s):

Movement Time ◽

Metabolic Cost ◽

Metabolic Energy ◽

Human Gait ◽

Cost Of Transport ◽

Relative Value ◽

Weighted Combination

Humans naturally select several parameters within a gait that correspond with minimizing metabolic cost. Much less is understood about the role of metabolic cost in selecting between gaits. Here, we asked participants to decide between walking or running out and back to different gait specific markers. The distance of the walking marker was adjusted after each decision to identify relative distances where individuals switched gait preferences. We found that neither minimizing solely metabolic energy nor minimizing solely movement time could predict how the group decided between gaits. Of our twenty participants, six behaved in a way that tended towards minimizing metabolic energy, while eight favoured strategies that tended more towards minimizing movement time. The remaining six participants could not be explained by minimizing a single cost. We provide evidence that humans consider not just a single movement cost, but instead a weighted combination of these conflicting costs with their relative contributions varying across participants. Individuals who placed a higher relative value on time ran faster than individuals who placed a higher relative value on metabolic energy. Sensitivity to temporal costs also explained variability in an individual's preferred velocity as a function of increasing running distance. Interestingly, these differences in velocity both within and across participants were absent in walking, possibly due to a steeper metabolic cost of transport curve. We conclude that metabolic cost plays an essential, but not exclusive role in gait decisions.

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