Aerobic Point Sytem

It's a pretty good basic system. 

If you train with power on the bike, Cycling Peaks uses TSS (Training Stress Score) which is essentially a system that counts "points" for your volume & intensity mix.  There are similar systems used for running, though they are less precise given measurement difficulties (Daniels suggests one in his book and you can google TRIMPs for another idea).  And there's been talk on ST and elsewhere about how to do a system for swimming as well, though this is likely even more arbitrary than running. 

But anything that helps you track your overall training "load" may be useful in mapping out your schedule--especially if you don't use a coach to help with it.  I'm starting to use TSS more and will probably look at tracking something for my running as well. 

I've been using TTS as well and used *sometimes* Daniels scoring system, but at the end, the time spent training and how my body feels is been the best system This winter I am planning to do some serious running and swimming and add quality sessions on the trainer; hence I might need to pay a closer attention to TSS and how that relates to my running volume