Swim Intervals & Drills Really Work

Several weeks ago I started doing some intervals as part of my swim training.  Just some 50's at 1:05 or 1:00 with 15 to 20 seconds rest with a goal of doing 12 of them.  I have yet to do 12 but twice I have done 10, other times my form when to pot so I stopped early. 

Anyway, I had a tri a few weeks ago and felt real good coming out of the water but the time was too short to be a accurate 400yrds.

Anyway, today, I did 600yrds straight in the pool for the 1st time in a while (it has probably been 2-3 months since I have done anything more than 200yrds at a time).  I knew I could do that but have just been focusing on form/drills & intervals lately. 

My time was 1:58 per 100.  I know that is not fast by any standard but it is about 20 seconds per 100 faster than any previous time I have posted on anything over 200 yrds and I was not  tired at the end.  This was just my warmup and I decided to just keep going until I got to 600 which is the distance of my next race in 4 weeks.

So what is the moral of the story.  I know swimming is the toughest for beginners and the lesson is this.  Do the drills consistently (I did not for a long time) and put some intervals in your training at some point to help push your cardio system further. 

Thanks for reading.