Effect of Swimming Training on Cardiac Morphological Factors, Apelin and Insulin like Growth Factor-1 in Male Wistar Rats

Different training methods have cardioprotective effects. The aim of this study was to examine the potential protective impact of continuous and interval swimming training with weights on cardiac morphological factors and serum levels of Apelin and Insulin-like Growth Factor-1 in male Wistar rats.

In this experimental study, 27 male rats divided randomly into the control (n=6), sham (n=5), interval (n=8) and endurance (n=8) groups. The endurance group swam for 12 weeks/5 days while swimming time increased incrementally. During the 12-week/4-day period, the interval group engaged in swimming exercises while gradually increasing the load and reducing the duration of rest. Apelin and Insulin like Growth Factor-1 concentration, heart weight and left ventricle weight were measured. One-way ANOVA was utilized and Tuckey-HSD test was used to point out the place of significance (α ≤ 0.05).

Findings showed that total heart weight in interval and endurance training compared to the control (P= 0.02 and P= 0.02 respectively) and sham (P= 0.02 and P= 0.02, respectively) significantly increased. Furthermore, the weight of the left ventricle showed a significant increase following endurance training in comparison to both the control (P= 0.02) and the sham groups (P= 0.02). Additionally, it was found to be significantly higher than the sham group following interval training. (P= 0.01). Apelin significantly increased in interval and endurance training compared to the control (P= 0.00 and P= 002 respectively) and sham groups (P= 0.02 and P= 0.04, respectively). Moreover, insulin like growth factor-1 significantly increased in interval and endurance training compared to the control (P= 0.01 and P= 0.01, respectively).

It appears that a 12-week swimming training program, particularly in an interval format, can induce physiological hypertrophy in cardiac tissue and provide cardiac protective benefits through the upregulation of Insulin-like Growth Factor-1 and Apelin.