Swimming frequency vs. duration

Former Member
Former Member
Which is better, swimming more frequently with shorter duration, or less frequently with longer duration? For example, (a) 7 days a week, each time 30 min, versus (b) 3-4 times a week, each time 1 hour? Here are the factors to consider: 1. Optimize fitness and health (not for competitive/hard core swimmer--I know that would require much more work!), 2. Minimize the chlorine effect on body. Comments welcome!