Thermography is often used to determine the effect of training and the risk of injury following training. However, thermograms taken at different intervals following exercise give different results. To determine the hourly variation in skin temperature in the upper and lower body immediately after strength training. A secondary objective was to determine if there are any bilateral differences for each area and moment of temperature recording. A longitudinal study design was employed to study the evolution of skin temperature over 8 h following an exercise protocol consisting of four sets of ten repetitions of the bench press, the leg press, the flat bench cable fly, and the leg extension. The sample consisted of fourteen physically active university students. Thermograms were recorded with a T335 FLIR® infrared camera (FLIR® Systems, Sweden). The temperatures from 24 regions of interest (ROIs) were obtained from the 78 anatomical regions provided by the Termotracker® software (ThermoHuman, Spain). A repeated-measures analysis of variance with planned repeated contrast tests was used to determine the effect of successive changes in temperature. Significant differences in body temperature over time were found in both the upper and lower body. No significant bilateral differences were found. Thermal images taken after training are affected by when they are taken, as the results show that in the trunk, the arms, and the legs the skin temperature drops significantly immediately after the exercise, then increases to the initial pre-exercise temperature and continues to increase in most cases.