Investigation of diurnal variability of Citrus lemon and Mentha piperita essential oils on 25 metre swimming and anaerobic performance parameters in elite pentathletes

This study examined the effects of Citrus lemon (CL) and Mentha piperita (MP) essential oils on the diurnal variability of 25-meter swimming sprint and anaerobic performance in elite pentathletes. Accordingly, the aim of the study was to determine how different essential oils applied in the morning and evening affect daily fluctuations in sports performance parameters. A total of 25 athletes, including 13 females and 12 males, with a mean age of 12.60±1.44 years, participated in the study. The athletes were evaluated under three test conditions: no intervention, CL, and MP essential oil application. Measurements were conducted both in the morning and evening. Anaerobic performance was assessed using the Countermovement Jump Test (CMJ), and swimming sprint performance was analyzed using the 25-meter freestyle swimming test. The essential oils were administered via inhalation. As a result of the measurements and comparisons, the effects of essential oil applications were observed. In terms of 25-meter swimming time, both CL and MP resulted in faster swim times compared to the non-intervention condition. In the morning, MP showed a significant improvement with 14.00±0.20 s compared to the control group's 14.50±0.30 s (p<0.05). Similarly, in the evening, a shorter time of 13.90±0.18 s was recorded compared to the control group's 14.30±0.28 s (p<0.05). According to the post hoc analysis of the 25-meter evening swimming data, both the CL and MP groups showed significant performance improvements compared to the non-intervention group (p<0.05); however, there was no significant difference between CL and MP (p>0.05). In CMJ measurements, both oils resulted in higher jump heights compared to the control, but these differences were not statistically significant (p>0.05). MP recorded 46.50±1.30 cm in the morning and 46.80±1.25 cm in the evening, while CL reached 46.00±1.40 cm in the morning and 46.20±1.35 cm in the evening. This study shows that CL significantly improved swimming sprint performance, although its effect on anaerobic performance was not statistically significant. MP also demonstrated a positive effect on swimming performance.