Hormonal and metabolic response in middle-aged women to moderate physical effort during aerobics

The aim of this study is to estimate the metabolic and hormone response in middle-aged women to acute physical aerobic exercise accompanied by music, the so-called "aerobics." The experiment (single 60-minute aerobics session) included 11 women aged between 30 and 50. The following variables were determined in blood samples collected from the participants four times (in fasting state [I], before exercise [II], after exercise [III], and after 12 hours of rest [IV]): concentration of lactic acid, glucose, free fatty acids, leptin, insulin, growth hormone, testosterone, and cortisol. Furthermore, the measurements included body mass before and after the exercise, and body temperature was taken in the auditory canal and on the forehead. The heart rate was registered during the exercise on a continuous basis. In all cases, the heart rate did not reach its maximum level, and on average, it amounted to approximately 70% of the maximum pulse rate. Therefore, this effort can be considered as submaximal. In all cases, we observed loss of body mass (from 0.2 to 0.7 kg) (p > 0.02) increase in the temperature measured on forehead. Significantly, accompanied by nonsignificant increase in the temperature measured on the tympanic membrane was registered. Single loading gives rise to change in hormone and metabolic profiles. Furthermore, a decrease in blood concentration of glucose before and after aerobics (p > 0.001) could be observed, and if the determination taken at measurement IV of glucose in blood is taken into consideration, then the value taken in measurement I is significantly the highest in relation to other measurements. Concentration of free fatty acids were increased (p > 0.002) after exercise and remained on the same level until the following day. The levels of insulin were significantly decreased, but growth hormone levels were increased. The exercise had no impact on testosterone concentration, whereas average blood concentration of leptin in the successive measurements showed a decreasing trend, although these changes are not statistically significant.Our observations provide the possibly full view of the physiologic reaction to the applied program of complex physical exercise accompanied by music, supporting the exercise's rhythm. The research program presented requires further investigation, e.g., what is the recommended frequency of the exercises applied on a weekly basis, and when should the intensity of the same increase.