Effects of concentric vs eccentric loading on cardiovascular variables and ECG
There is a paucity of information concerning the cardiovascular responses and adaptations to strength training. Limited evidence suggest that which particular type of resistance exercise could be more tolerable as well as potentially safer for people with cardiac diseases or impairments. So, the aim of study was to determine and compare the effect of concentric and eccentric loading on cardiovascular variables and ECG.20 Young healthy students (mean age 20 ± 4 years) participated and were randomly divided into two groups- Experimental & Control. Pre & Post training readings were taken for following Parameters –Heart Rate, Blood Pressure, Mean Arterial Pressure, Rate Pressure Product and ECG. At first testing bout, participants performed concentric exercises (at 75% of 10 RM). Participants returned 10 days after the first session to perform exercises using the eccentric contraction type. Related‘t’ test and one way ANOVA was applied for statistical analysis between groups. Cardiovascular measures collected from subjects were significantly lower during eccentric than during concentric bouts in all subjects (p<0.01) and ECG showed no significant changes after both training protocols (p>0.05). So, it can be concluded that since eccentric exercise produces less cardiopulmonary demands so are more suitable for persons with low exercise tolerance, who are at the risk of adverse cardiopulmonary events and for improving and maintaining cardiac fitness.
Keywords: Eccentric Exercise, Concentric Exercise, ECG, Cardiopulmonary demands, Young population.