The winter months, as a triathlete, see a lot of your usual outdoor pursuits seriously curtailed.  This could be due to poor weather, lack of daylight or general lack of oomph.  I, therefore, see the winter period as an ideal time to work on your swimming weaknesses in the pool. 

This does not mean that you should just get in the pool and do endless lengths ploughing up and down covering huge distances.

The winter is an ideal period to take some time out of your program to improve your swimming so that when you hit spring again you are better equipped with dealing with those bigger distances required.  This means identifying weaknesses and planning your sessions accordingly.

In my experience the two things that a lot of triathletes could work on in terms of their swimming are technique and general swim speed.

As a rough rule of thumb if you are swimming at 2-30 minutes (or more) per 100m then your focus should be on improving your technique because in the short, medium and long term this is where there are still loads of gains to be made.  This means your swim training should be mainly short distance repeats concentrating on good form, giving yourself sufficient rest to swim each length with good form.  Using different sets/lengths to isolate various technique pointers.

As you start getting towards the 2 min mark for 100m you are probably ready to start putting a little bit of pressure on this technique.  I don’t think you should at this point start just swimming loads of lengths but start to introduce some short distance repeats (says 25s and 50s) where you are trying to build the pace that you can hold this technique for.  We are not talking sprint work but, for example, if you want to be able to swim at faster than 2 min per 100 you need to be able to swim 25m repeats in under 30 seconds first. 

These sessions do not need to be long and laborious, in fact if you are quite new to swimming you are probably better of doing more sessions of a shorter duration rather than the other way around.

Even for the pretty experienced swimmer I think taking a bit of time out during the winter program to improve your technique and reduce the distance and work on more stuff is probably useful in terms of making you a better swimmer.

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