I´ve just watched for 10th time the GPP Essentials DVD. 
Talking about Tempo Sessions;
what should be a good interval rest between reps of 100, 150 and 200m in a workout with splits as follow:
100 100 100
100 200 100
100 200 200
100 150 150
Walk 50 meters between reps. and 100 meters between sets.
Thats a very good rest ration, but then comes a problem. You walk faster in the first few runs and then you tend to walk way much slower after mid point and towards the end. I’d say stick to the 1:1 - 1:2 ratio if your good enough. If you run 100m on 15 then take 30 off and so on. If you can’t then take 1:3 and so on. between sets you can take something like 2 minutes or so. Moniter your rest and record cause you might want to know where you started from each year to know whats going on.
Thats a good suggestion however it becomes a big pain in the butt to keep cliking your watch and resetting it ever 15-30 seconds. Some watches like my Nike watch actually you have to hold down the button for 5 seconds for the thing to clear.
I personally do not like to time tempo. Maybe with new athletes early in the yr. it may be a good idea for them to learn pace and how long they should rest for but later in the yr when you are in the swing of things i think as long as you keep your reps and your rest (walk pace) consitent you will not have any problems.
You’re right man. It does take up a lot of consentration and becomes a pain when you are all out. But then I’m used to it nowadays. + you can let your coach time you. Do you have one?
check your watch. some will allow to have 30 interval automatically.
http://www.regenerationlab.com/archives/000025.php
pace clocks make the difference, see charlie the only benefit of swimming training…
Pace clocks work great when doing tempo runnign in place in the pool. I use it everytime i do a pool session.
But if you dont have a coach it would be hard to see the pace clock from across the track.
two clocks…one on each end.