Exercise-Associated Thermographic Changes in Young and Elderly Subjects

Abstract

This study aimed at evaluating the thermographic changes associated with localized exercise in young and elderly subjects. An exercise protocol using 1 kg load was applied during 3 min to the knee flexors of 14 elderly (67 +/- 5 years) and 15 young (23 +/- 2 years) healthy subjects. The posterior thigh's skin temperature of the exercised limb and contralateral limb were measured by infrared thermography on pre-exercise, immediately post-exercise, and during the 10-min period post-exercise. Difference (p < 0.01) between elderly and young subjects was observed on pre-exercise temperature. Although differences were not observed between pre-exercise and immediately post-exercise temperature in the exercised limb, thermographic profile displayed heat concentration in exercised areas for both groups. Temperature reduction was only observed for the young group on the 10-min post-exercise (p < 0.05) in the exercised limb (30.7 +/- 1.7 to 30.3 +/- 1.5 degrees C). In contrast, there was a temperature reduction post-exercise (p < 0.01) in the contralateral limb for both groups. These results present new evidences that elderly and young subjects display similar capacity of heat production; however, the elderly subjects presented a lower resting temperature and slower heat dissipation. This work contributes to improve the understanding about temperature changes in elderly subjects and may present implications to the sports and rehabilitation programs.

Time required to stabilize thermographic images at rest

“…Studies in the field of thermography have evaluated only the lower limbs [14], hands [8] or whole body [4]. The results of this study suggest different acclimatization times for different body areas.…”

“…The scientific use of thermography began in medical research, in which it has been used to diagnose vascular disease [11], inflammation [12], tumors [6,13], metabolic disorders and abnormalities in body temperature [12]. In the field of physical activity and sports, some studies have used the technique to study differences in thermogenesis between young and elderly people [14], the effect of exercise on hand temperature [8], and the distribution and variation of T SK during progressive exercise [4].…”

“…Roy and collaborators [16] performed a study in which thermography was used to analyze the time necessary for the temperature in the region of the spine to stabilize and suggested a minimum time of 8 min and maximum of 16 min for reliable measurements [16]. The recommended acclimatization time varies between studies of skin thermometry, with periods of 10 min [14,17], 15 min [8] and 20 min [4] suggested for the subject to remain at rest in a room with controlled temperature and humidity. This variation may be influenced by environmental conditions, especially by the temperature outside the test room.…”

“…This lack of consensus [4,8,[14][15][16][17] makes it difficult to determine the optimal acclimatization protocol because each study recommends a different acclimatization period to achieve a stable T SK to ensure the homogeneity of results and allow consistent interpretation and comparison of results between studies. Consequently, the objective of this study was to identify the time required to achieve a stable T SK at rest in a group of young men and women.…”

Reliability and validity of skin temperature measurement by telemetry thermistors and a thermal camera during exercise in the heat

“…However, the differences observed in T SKIN from TC were sizeable. Utilising TC in a dynamic, ecologically valid situation is in contrast to the techniques adopted in the majority of previous research with thermal cameras that has shown broadly encouraging results (Merla et al 2010;Ferreira et al 2008;Chudecka & Lubkowska 2012), albeit not unanimously (Fernandes et al 2014). Specifically, tripod mounted cameras have been used to generate thermograms of participants who have spent up to 40 minutes in thermo-neutral conditions.…”