Relationship between foot eversion and thermographic foot skin temperature after running

Short-Term Skin Temperature Responses to Endurance Exercise: A Systematic Review of Methods and Future Challenges in the Use of Infrared Thermography

BACKGROUND

Body temperature is often assessed in the core and the skin. Infrared thermography has been used to measure skin temperature (Tsk) in sport research and clinical practice. This study aimed to explore the information reported to date on the use of infrared thermography to detect short-term Tsk responses to endurance exercise and to identify the methodological considerations and knowledge gaps, and propose future directions.

METHOD

A web search (PubMed, Science Direct, Google Scholar, and Web of Science) was conducted following systematic review guidelines, and 45 out of 2921 studies met the inclusion criteria (endurance sports, since 2000, English, full text available).

RESULTS

A total of 45 publications were extracted, in which most of the sample were runners (n = 457, 57.9%). Several differences between IRT imaging protocols and ROI selection could lead to potential heterogeneity of interpretations. These particularities in the methodology of the studies extracted are widely discussed in this systematic review.

CONCLUSIONS

More analyses should be made considering different sports, exercise stimuli and intensities, especially using follow-up designs. Study-derived data could clarify the underlying thermo physiological processes and assess whether Tsk could be used a reliable proxy to describe live thermal regulation in endurance athletes and reduce their risk of exertional heat illness/stroke. Also more in-depth analyses may elucidate the Tsk interactions with other tissues during exercise-related responses, such as inflammation, damage, or pain.

Adaptive clip-limit-based bi-histogram equalization algorithm for infrared image enhancement

Infrared (IR) images are basically low-contrast in nature; hence, it is essential to enhance the contrast of IR images to facilitate real-life applications. This work proposes a novel adaptive clip-limit-oriented bi-histogram equalization (bi-HE) method for enhancing IR images. HE methods are simple in implementation but often cause over-enhancement due to the presence of long spikes. To reduce long spikes, this work suggests to apply a log-power operation on the histogram, where the log operation reduces the long spikes, and power transformation regains the shape of the histogram. First, a histogram separation point is generated applying the mean of the multi-peaks of the input histogram. After that, an alteration in the input histogram is done using the log-power process. Subsequently, a clipping operation on the altered histogram followed by redistribution of the clipped portion is performed to restrict over-enhancement. Next, the modified histogram is sub-divided using the histogram separation point. Finally, the modified sub-histograms are equalized independently. Simulation results show that the suggested method effectively improves the contrast of IR images. Visual quality evaluations and quantitative assessment demonstrate that the suggested method outperforms the state-of-the-art algorithms.

Effect of custom-made and prefabricated foot orthoses on kinematic parameters during an intense prolonged run

Foot orthoses are one of the most used strategies by healthy runners in injury prevention and performance improvement. However, their effect on running kinematics throughout an intense prolonged run in this population is unknown. Moreover, there is some controversy regarding the use of custom-made versus prefabricated foot orthoses. This study analysed the effect of different foot orthoses (custom-made, prefabricated and a control condition) on spatio-temporal and angular (knee flexion and foot eversion) kinematic parameters and their behaviour during an intense prolonged run. Twenty-four recreational runners performed three similar tests that consisted of running 20 min on a treadmill at 80% of their maximal aerobic speed, each one with a different foot orthosis condition. Contact and flight time, and stride length and stride rate were measured every 5 min by an optical measurement photoelectric cell system. Knee flexion and foot eversion kinematic parameters were measured by two high-speed cameras. No significant differences were found between the different foot orthoses in any of the time points studied and between the interaction of foot orthosis and behaviour over time, in any of the variables studied (P > 0.05). The use of custom-made and prefabricated foot orthoses during an intense prolonged run does not produce changes in spatio-temporal and kinematic parameters in healthy runners. These results suggest that a healthy runner maintains its ideal movement pattern throughout a 20 minute prolonged run, regardless the type of foot orthosis used.

Review on Wearables to Monitor Foot Temperature in Diabetic Patients

One of the diseases that could affect diabetic patients is the diabetic foot problem. Unnoticed minor injuries and subsequent infection can lead to ischemic ulceration, and may end in a foot amputation. Preliminary studies have shown that there is a positive relationship between increased skin temperature and the pre⁻ulceration phase. Hence, we have carried out a review on wearables, medical devices, and sensors used specifically for collecting vital data. In particular, we are interested in the measure of the foot⁻temperature. Since there is a large amount of this type of medical wearables, we will focus on those used to measure temperature and developed in Spain.