Swim pace for long, slow swims???

In general there is less change with swim paces from fast to slow.  In general, I would set your swim pace by a time trial of at least 15 minutes.  The average pace per 100 for this is what you would define as T pace and would set up the follow paces (roughly - they will change based on the individual):

Easy - T pace + 20% (2:00+/100m)
Moderate - T pace + 10% (1:50/100m)
Steady - T pace (1:40/100m)
Fast - T pace - 5% (1:35/100m)
Sprint - T pace - 10% (1:30/100m)

In addition, I included an example for a swimmer who average 1:40/100m.  Following this approach should give you an idea of where you paces lie.

Swimming is different than running though and almost every workout will include at least some swimming at T pace and most triathletes will not be swimming enough for a long, slow swim.  Instead, they will use easy to warmup and for drills, do longer repeats at a moderate or steady pace and short repeats at fast or sprint depending on the purpose of the workout.

Shane

Thanks SO much to you both, Shane and Steve.  Very helpful explanations.  

When I do the calculations suggested by Shane it is interesting that there IS about 20" between easy and T-pace.   I only learned to swim just over 3 years ago at a local triathlon training centre and am confident that my form is good despite my slow pace - although ALWAYS room for continuous improvement.   I am 56, 5' tall with SHORT arms so have a few challenges that others don't have but I do love swimming.  

From your calculations Steve, I think my paces should be something like the following:

2.45/100 Easy

2.31 Moderate

2.18 Steady (Tpace)

2.11 Fast

2.05 Sprint

Can you tell me if that looks right.   I generally do the type of workouts you mentioned, but not sure what you meant exactly by not having enough time for long, slow swims.  

Thanks again to you both.  

Those look fairly reasonable; the real test is how they feel to you.  Like I said, this should give you a starting point so you can catch the pace clock to see how these fit with how you percieve your exertion during swimming.

As for the long, slow swimming; most triathletes are never going to put enough time in the pool to benefit from long, slow swimming.  Training load is a combination of volume and intensity and unless you are putting in huge volume in the pool (say 20k+ a week) then you will be better served by swimming at a higher intensity when you are at the pool.

Shane

In additon to the posted above, IMO beyond warm and cool down you don't want to spend much time swimming easy in particular when most Triathletes swim 2-3K per session and no more than 5-8k x week. Even on long sets you should be pushing moderate, threshold and V02max rather often, otherwise you'll just learn how to swim slow.

OMG, I am SO impressed and grateful to have received such valuable advice from such expert athletes.    I do swim around 6500K per week at this point and swim 3x per week.   

I do have another question now, if you don't mind.   I have been doing mostly 50's - eg. 15x50 on 1.25 and have done them on 1.20, keeping a 1.05/1.07 pace.     Have done sets of 100 only occasionally, thinking I should keep on reducing the RI on the 50's until I can keep the pace with no RI's.  

Would I be wiser to start doing more 100's?  I can comfortably do 8 x 100 on 2.40 keeping my pace at about 2.22.     Any suggestions?  

I am very excited about next week's training sessions.    

I'm a huge fan of mixing it all up.  I'd like short, quick stuff, but you're not swimming 50's or 100's with rest intervals in a tri.  So I think you need sets of longer yardage too.  Sometimes I'll do sets of 200s, sometimes sets of 500s, sometimes a ladder (100,200,300,400,500,400,300,etc).  Sometimes go fast and give yourself longer rest, sometimes go fast and do short rest intervals.  Sometimes keep the pace moderate.  Etc.

Another echo -- my recent experience backs up what the smart guys are suggesting above.

I started swimming in December 2008.  I spent about three months swimming slow and working on form.  At that point I noticed that my pace had more-or-less plateaued even though I was swimming 5-6 times a week for an hour or more each time.

I saw people (esp. Newbz) recommend swimming more hard, fast intervals to improve speed, so I decided to give it a shot. 

So, for the last ~1.5 months I've been swimming a lot of 100y and 200y intervals (like 8x100y on 1:30, or 4x200y on 3:00).  I still swim 5-6 times/wk for about 1 hour, but include at least a couple hard intervals in almost every workout.  This helped me drop my long, steady pace for 500y from about 1:30/100y to about 1:23/100y, and it is still dropping (knock on wood!).  My impression is that the key to this improvement has been the hard intervals.

Another interesting thing about swimming faster is I've noticed my form has improved as I've gotten stronger in the water.

You swim 100 yards in 20 seconds?  I can't go that fast in a speed boat.