TY - JOUR
T1 - Association between foot thermal responses and shear forces during turning gait in young adults
AU - Gonzalez, Angel E.
AU - Gutierrez, Ana Pineda
AU - Kern, Andrew M.
AU - Takahashi, Kota Z.
N1 - Funding Information:
This work was supported by the National Institutes of Health [P20GM109090 to Kota Takahashi]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Publisher Copyright:
© 2021 PeerJ Inc.. All rights reserved.
PY - 2021/1/18
Y1 - 2021/1/18
N2 - Background. The human foot typically changes temperature between pre and post-locomotion activities. However, the mechanisms responsible for temperature changes within the foot are currently unclear. Prior studies indicate that shear forces may increase foot temperature during locomotion. Here, we examined the shear-temperature relationship using turning gait with varying radii to manipulate magnitudes of shear onto the foot. Methods. Healthy adult participants (N = 18) walked barefoot on their toes for 5 minutes at a speed of 1.0 m s−1 at three different radii (1.0, 1.5, and 2.0 m). Toe-walking was utilized so that a standard force plate could measure shear localized to the forefoot. A thermal imaging camera was used to quantify the temperature changes from pre to post toe-walking (1T), including the entire foot and forefoot regions on the external limb (limb farther from the center of the curved path) and internal limb. Results. We found that shear impulse was positively associated with 1T within the entire foot (P < 0.001) and forefoot (P < 0.001): specifically, for every unit increase in shear, the temperature of the entire foot and forefoot increased by 0.11 and 0.17 ◦C, respectively. While 1T, on average, decreased following the toe-walking trials (i.e., became colder), a significant change in 1T was observed between radii conditions and between external versus internal limbs. In particular, 1T was greater (i.e., less negative) when walking at smaller radii (P < 0.01) and was greater on the external limb (P < 0.01) in both the entire foot and forefoot regions, which were likely explained by greater shear forces with smaller radii (P < 0.0001) and on the external limb (P < 0.0001). Altogether, our results support the relationship between shear and foot temperature responses. These findings may motivate studying turning gait in the future to quantify the relationship between shear and foot temperature in individuals who are susceptible to abnormal thermoregulation.
AB - Background. The human foot typically changes temperature between pre and post-locomotion activities. However, the mechanisms responsible for temperature changes within the foot are currently unclear. Prior studies indicate that shear forces may increase foot temperature during locomotion. Here, we examined the shear-temperature relationship using turning gait with varying radii to manipulate magnitudes of shear onto the foot. Methods. Healthy adult participants (N = 18) walked barefoot on their toes for 5 minutes at a speed of 1.0 m s−1 at three different radii (1.0, 1.5, and 2.0 m). Toe-walking was utilized so that a standard force plate could measure shear localized to the forefoot. A thermal imaging camera was used to quantify the temperature changes from pre to post toe-walking (1T), including the entire foot and forefoot regions on the external limb (limb farther from the center of the curved path) and internal limb. Results. We found that shear impulse was positively associated with 1T within the entire foot (P < 0.001) and forefoot (P < 0.001): specifically, for every unit increase in shear, the temperature of the entire foot and forefoot increased by 0.11 and 0.17 ◦C, respectively. While 1T, on average, decreased following the toe-walking trials (i.e., became colder), a significant change in 1T was observed between radii conditions and between external versus internal limbs. In particular, 1T was greater (i.e., less negative) when walking at smaller radii (P < 0.01) and was greater on the external limb (P < 0.01) in both the entire foot and forefoot regions, which were likely explained by greater shear forces with smaller radii (P < 0.0001) and on the external limb (P < 0.0001). Altogether, our results support the relationship between shear and foot temperature responses. These findings may motivate studying turning gait in the future to quantify the relationship between shear and foot temperature in individuals who are susceptible to abnormal thermoregulation.
KW - Biomechanics
KW - Curved path walking
KW - Feet
KW - Locomotion
KW - Thermoregulation
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U2 - 10.7717/peerj.10515
DO - 10.7717/peerj.10515
M3 - Article
C2 - 33552710
AN - SCOPUS:85099761668
VL - 9
JO - PeerJ
JF - PeerJ
SN - 2167-8359
M1 - e10515
ER -