Purpose:
Homocysteine is a non-protein amino acid and elevated blood levels are often caused by inappropriate lifestyles, leading to atherosclerosis and cardiovascular diseases. The aim of this study was to determine the levels of homocysteine after a 9-month training program.

Methods:
The group studied consisted of obese and overweight women, as well as women with normal body mass. During the training program, control examinations were carried out four times and the following parameters were analyzed: homocysteine blood levels, body mass, BMI, a single 10-minute exercise at a workload of 100W and the VO2max measured using the Astrand–Ryhming method.

Results:
The highest homocysteine levels were found in obese women and the lowest in lean women. Higher levels were observed in older women (aged over 50 years) compared to younger women (aged below 50 years). The differences were clearly visible in obese women. Homocysteine levels decreased after the 9-month training program. A single exercise performed every three months during the training program resulted in an increase in homocysteine levels or no changes.

Conclusions:
Higher homocysteine levels in the blood after a single exercise are likely caused by faster metabolism of this amino acid. Exercise of moderate intensity leads to a decrease in homocysteine levels in the blood, especially in obese women. Regular physical activity should therefore be recommended not only to prevent and treat obesity but, most importantly, atherosclerosis.