Your heart rate is important. I do easy satisfying low-level cardio at a heart rate of around 105-125 bpm. Starch is certainly optimal post-workout and preferable to sugar if you are looking for lean gains. White rice is the best source of carbs for spiking your insulin post-workout and building muscle.
Starch pre-workout has more value for strength-building.
I'm doing both.
F 5 ft 3. HW: 196 lbs. Primal SW (May 2011): 182 lbs (42% BF)... W June '12: 160 lbs (29% BF) (UK size 12, US size 8). GW: ~24% BF - have ditched the scales til I fit into a pair of UK size 10 bootcut jeans. Currently aligning towards 'The Perfect Health Diet' having swapped some fat for potatoes.