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The purpose of this study was to determine if curved non-motorized treadmills can reproduce overground running better than motorized treadmills by analysing the differences in joint kinematics (hip, knee, and ankle) using SPM. Nineteen recreational runners completed three randomized running tests on these surfaces. Kinematic data from the hip, knee, and ankle joints were collected. Two-tailed SPM t-tests were performed to analyse time-continuous gait cycles in three anatomical planes of each joint. Higher within-subject variability was observed in the frontal and transverse planes during curved non-motorized treadmill running. SPM analysis showed more significant differences ( p  < 0.05) between curved non-motorized treadmill and overground than between motorized treadmill and overground, mainly in knee (from 12% to 30% and 93% to 99% of the gait cycle) and ankle (from 19% to 23% of the gait cycle) in the sagittal plane. Therefore, running on curved non-motorized treadmills is more biomechanically different compared to overground than motorized treadmills, and might not be the best strategy to replicate overground running in terms of joint kinematics during highly controlled research studies. However, they could be an interesting tool in rehabilitation or training environments since the changes observed in joint kinematics were likely not functionally relevant.

Skin temperature assessment has received much attention as a possible measurement of physiological response against stress produced by exercise and research studies usually measure skin temperature 24 or 48 h after exercise. Scientific evidence about skin temperature evolution during the 24-h period immediately after exercising is, however, scarce. The aim was to assess the effect of a 10 km run at moderate intensity on baseline skin temperature and thermal response after a cold stress test during that 24 h period. Fourteen participants were measured before, immediately after, and at 2, 5, 9 and 24 h after a 10 km run at a perceived exertion rate of 11 points (max 20 points). Fourteen control participants who undertook no exercise were also measured during that day. The measurements included muscle pain and fatigue perception, reactive oxygen species, heart rate variability, skin temperature of the lower limbs, and skin temperature after cold stress test. Exercise resulted in a skin temperature increase (e.g., 0.5-1.3 °C of posterior leg 9 h after exercise) and this effect continued in some regions (0.4-0.9 °C of posterior leg) over that 24 h period. However, the thermal response to the cold stress test remained the same (p > 0.05). In conclusion, 10 km aerobic running exercise results in a skin temperature increase, peaking at between 5 and 9 h after exercise, but does not alter the thermal response to a cold stress test. This study provides a sound basis for post-exercise skin temperature response that can be used as a setting-off point for comparisons with future studies that analyze greater muscle damage., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)