I don't want to bore you guys with the details, but earlier this evening I became nostalgic and decided to re-read some of the more epic fight scenes in the Wheel of Time book series. One of my personal favorite fight scenes occurs at the end of the Shadow Rising, where Rand faces off and successfully captures Asmodean after an awesome chase scene.

While I was pouring back over the material, I noticed that after Rand narrowly escapes death by tumbling out of the Gateway, he begins to describe a sort of strain on saidin. This strain appears to occur as soon as he enters Rhuidean. Here are some examples:

Rand channeled--it seemed oddly difficult; he pulled at the heart of saidin, wrenched at it until it raged into him--he channeled, and thick bolts of jagged lightning shot from the dome-clouds.
-The Shadow Rising, page 967

Here's another example:

He had to stop Asmodean. Straining--and it took strain--he threw lightning ahead, balls of fire ripping up out of the ground, anything to slow the red-coated man.
-The Shadow Rising, page 968

What is this "strain" described in the previous passages? Does it have anything to do with the magic of Rhuidean, or is it more or less a result of Rand being stressed out from channeling continuously, pushing beyond fatigue and exhaustion in order to achieve a single-minded purpose? Please forgive me if the answer is obvious. It has been a long time since my last read, and I thought it might help to collect some opinions.