Changes Of Plantar Temperature And Its Relationship With Plantar Pressure Under Different Temperature Conditions

Objective: Thermal comfort is an important physiological requirement of the human body.The human body can stabilize itself in a thermal comfort state through the internal adjustment system of the body,and can also achieve heat balance of the human body by means of heating and cooling.The skin on the surface of the human body plays an important role in regulating body temperature.Although the proportion of the skin of the foot is small,its importance cannot be ignored.Especially during exercise,the skin of the foot as a sensory organ has the ability to receive the foot pressure,vibration stimulation and nerve signals.Conducting and other functions provide important feedback for adjustment actions.Therefore,this paper studies the relationship between the changes of plantar temperature and the relationship between temperature and plantar pressure during exercise in different temperature environments,and discusses the internal mechanism of the temperature change of the foot,which provides an important reference and related for the improvement of sports equipment and functional development.data support.Methods: In this experiment,10 healthy male amateur runners were selected.The experiment was divided into two stages,which were carried out in the natural room temperature environment of 32 ± 1.5°C in summer and 15 ± 1.7°C in winter.The trend of foot temperature and foot during running were recorded.Bottom pressure variation characteristics.The speed of the treadmill was set at 8km/h.The average skin temperature of the foot of the subject was recorded every 3 minutes using an infrared thermal imager.A total of 12 records were recorded.The soles of the feet were divided into big toe(Hllux-H)and other toes(Other Toes-OT),Medial Forefoot-MF,Lateral Forefoot-Lf,Medial Midfoot-MM,Lateral Midfoot-LM,Medial Rearfoot-MR)and the lateral area of the Lateral Rearfoot-LR.At the same time,the plantar pressure data of each area was collected using the Novel insole and recorded once every 3 minutes for a total of 12 records.The collected temperature data and kinematic data were processed by software for bad values,and then the data were subjected to normality test,descriptive analysis,independent sample T test,analysis of variance and correlation analysis using SPSS 19.0 software.Focus on the temperature changes in different regions of the foot in different temperature environments,and analyze the relationship between plantar pressure and temperature.Results: In the high temperature environment in summer,the initial temperature to the highesttemperature range is 35.7 °C-39 °C.There is no difference in the same movement time between the various regions of the foot.In the low temperature environment,the foot temperature varies from15.1 °C to 31.8 °C.The arch has the highest temperature and the toe temperature is the lowest.During exercise,the skin temperature of the plantar skin in winter was lower than that in summer,and the difference was very significant(P<0.001),the average temperature of the entire plantar skin increased by 2 °C in the low temperature environment,while the temperature in the high temperature environment has risen by 12.7 °C,the lower the skin temperature of the plantar,the faster the rate of increase.There is no correlation between plantar pressure and temperature.Conclusion and suggestion: in the temperature rising stage of the motion process,the initial temperature is negatively correlated with the rate of temperature rise,that is,the higher the initial temperature,the slower the temperature rise;The lower the initial temperature,the faster the region's temperature rises.The changes of plantar temperature were significantly different in different temperature environments.The plantar temperature in summer was higher than that in winter,and the difference was significant.In addition,different physiological reactions occurred.In the high temperature environment,the foot temperature decreased slightly at the beginning of exercise,while no similar reaction was found in the low temperature environment,which may be caused by the capillary contraction threshold.When exercising in high temperature environment,the frequency of sweating in the foot is higher than that in low temperature environment.Therefore,in summer sports,sports shoes are required to have better ventilation function to ensure the thermal comfort of the foot.The correlation between plantar pressure and temperature change was not found through analysis,so the internal heat production during exercise was greater than the influence of external force stimulation.When developing footwear products with foot thermal comfort under motion,foot temperature changes in different temperature environments should be considered.According to the results of this study,in the high-temperature environment,the design of sneakers should focus on the overall air permeability of the shoes,while in the low-temperature environment,the toes and heel parts should pay attention to strengthen warmth,and the toes can be designed as the heating part.