"Flipping the switch" and strength rides

I mentioned in an earlier post the bike testing revealed a good VO2max of 64, but also showed that I had a low lactate threshold (LT) relative to my VO2max. LT is highly trainable, but VO2max is pretty much set by genetics and health history (smoking, bronchitis, etc.), although it has a little flexibility. So I need to raise my LT through training. Tony has prescribed two ways for me to raise my LT.

The first is by training my body to transition into aerobic, lactate-producing mode at a higher heartrate. He says the best way to accomplish that is by "flipping the swich" over and over. That means going from my aerobic threshold (the point at which you start burning mostly fat for energy -- that's 114 bpm for me) as quickly as possible to 10 or so bpm above my LT. Short hill repeats are a good way to do that, but as I have learned, also a very uncomfortable way (some might say painful). As Tony told me, the body does not like to cross that threshold that much that frequently.

A second way to raise LT is to do 'strength workouts.' At first I thought this meant weight lifting, but it's not. It's riding longer distances at slightly over my LT. The cadence-power testing that I've been doing is a good example, I guess. I have not been prescribed any workouts for this yet.