Minimum Cost of Transport in Human Running Is Not Ubiquitous

Abstract

The findings confirm the existence of optimal speed for human running in some but not all participants. Those exhibiting COTmin undertook higher volume of running, ran with a cadence that was more consistently modulated with speed, and tended to be aerobically fitter. The ability to minimize energetic CoT seems not to be a ubiquitous feature of human running but may emerge in some individuals with extensive running experience.

The Pandolf load carriage equation is a poor predictor of metabolic rate while wearing explosive ordnance disposal protective clothing

“…Martin and Nelson (1986) identified an increase in walking speed results in greater flexion of the trunk and an increase in stride rate coupled with a simultaneous decrease in stride length and swing rate during backpack load carriage. As a result, alterations in an individual's preferential gait mechanics reduce the mechanical efficiency of motion (Cher, Stewart, andWorringham 2015, Donelan, Kram, andKuo 2001). Greater metabolic rates observed when compared to the Pandolf equation at faster walking speeds (Figure 4b) may be a product of the relative thickness and cumbersome size of the PPC.…”

People choose to run at their optimal speed

“…People who are unable to run aerobically at speeds above 4.2 ms −1 would not be able to have an optimal speed detected using indirect calorimetry as the method of data collection simply because there would be no curve upwards at the higher speeds (indirect calorimetry would dramatically underestimate the amount of energy being used in anaerobic respiration). The necessity of having runners fit enough to run aerobically at higher speeds has been used to suggest that some people do not have an optimal running speed (Cher, Stewart, & Worringham, ) but this does not simultaneously mean that these same people have a non‐significant relationship between CoT and speed, particularly gross CoT. If some people are not habitual runners, or only practice a small range of speeds for short distances, then they still will not have a horizontal line (i.e., nonsignificant) relationship between gross CoT and speed, because of the extremely high cost of traveling at very slow running speeds—the very speeds that are suggested to be used by endurance hunters (Liebenberg, ).…”

The Effects of Metabolic Work Rate and Ambient Environment on Physiological Tolerance Times While Wearing Explosive and Chemical Personal Protective Equipment

“…Skinfold thickness measures were obtained, using Harpenden (John Bull, West Sussex RH15 9LB, UK) callipers, at eight sites (biceps, triceps, subscapular, iliac crest, supraspinale, abdominal, front thigh, and medial calf). was determined by indirect calorimetry during a progressive incremental running protocol on a motorised treadmill [ 27 ]. Participants were also provided with the opportunity to familiarise to the PPE ensemble by walking around the laboratory and on the treadmill at the speeds to be utilised for the trials.…”