Abstract. The aim of this paper is to verify whether step aerobics train-ing (SAT) has an impact on the temperature of deep muscles of the spineof young, healthy subjects and if there exists a relationship between the max-imal oxygen uptake (VO2max) and thermal results. The study was conductedin a group of 21 subjects of both sexes, aged 20.2±0.38. The step aerobicstraining sessions lasted 30 weeks, one training session perweek, 60 minutesper session. Thermograms of the spine were taken with the useof an infraredthermographic camera. Instrumental measurements included BMI, vital capac-ity of the lungs, and maximal oxygen uptake (VO2max). After a30-week-long SAT, a statistically significant increase in the average temperature of themuscles of the thoracic and lumbar spine was observed in subjects of bothsexes (1.2◦C and 1.28◦C, respectively, p<0.05). At the same time, VO2maxincreased from 42.98 ml/kg/min to 43.6 ml/kg/min in male subjects and from40.4 ml/kg/min to 41.1 ml/kg/min in female subjects (p>0.05). The rela-tionship between VO2max and temperature of the muscles of the thoracic andlumbar spine after the 30thSAT was not statistically significant (r = – 0.28;p = 0.226; r = – 0.11; p = 0.634, respectively). The study showed that a 30-week-long step aerobics training (SAT) had a positive impact on thermoregulationof apparently healthy male and female subjects aged 20. Furthermore, it canbe safely assumed that thermography may be used as a non-invasive method ofexamination of the thermoregulation mechanism of SAT participants.