Abstract
Background: The cardiac morphology and functioning undergoes a variety of changes on physical training, and it depends on the type of training the person undergoes. Endurance training and speed training are the two major classifications in it, and it is essential to know which type overruns the other in increasing the cardiac functioning.

Aims and Objective: To compare the cardiac functioning of three groups of human participants’ viz., endurance athletes, speed athletes, and untrained individuals, by measuring their VO2 max and QRS wave amplitude.

Materials and Methods: Fifteen endurance athletes (mean age ± SD: 20.27 ± 1.58 years), 15 speed athletes (mean age ± SD: 20.15 ± 1.85 years), and 15 control subjects (mean age ± SD: 19.33 ± 0.82 years) were recruited into the study. VO2 max was obtained from three tests (beep test, Uth–Sorensen–Overgaard–Pedersen method, and Cooper variation method), and mean QRS wave amplitude was measured using Minnesota code of classification.Statistical analysis was done using ANOVA test.

Result: The VO2 max (V) and QRS wave amplitude (R) of endurance (V: P < 0.001; R: P < 0.001) and speed athletes (V: beep test—P < 0.05, others—P < 0.001; R: P < 0.05) were significantly higher than that of the untrained individuals. When compared between the two athletic groups, endurance athletes showed significantly higher values than the speed athletes in both the parameters (V: P < 0.001; R: P < 0.001).

Conclusion: Both endurance and speed training enhance the cardiac functioning when compared with the untrained individuals significantly. But, endurance training shows an edge over speed training in increasing the effectiveness of working of heart.

Key words: Cardiac Functioning; Endurance Athletes; Speed Athletes; QRS Wave Amplitude; VO2 max