Thursday, December 14, 2006

LT test and getting clocked.

Standard warning: Do not attempt this test without the consent of a physician. I'm being serious, the last thing I want on my concious is being responsible for someone else's heart attack.

So what is an LT test? LT stands for lactate threshold which is the level of exercise intensity when lactate starts to accumulate in the blood and you change from a primarly fat burning to a glycogen (carbs) burning metabolism.
Methodology: Get yourself good and warmed up ending with a few stride repeats to jack up the heart rate. Once warmed up run a 30 minute time trial. At the 10 minute mark, hit the lap button on your heartrate monitor, your LT will be your average heartrate for the last 20 minutes. You should give the time trial 100 percent effort and be pretty well spent at the end of it. Ideally, you want a hard, but consistent pace throughout the whole time trial.

Ok, so that's the nuts and bolts of the matter. Tuesday seemed like a good time for a LT test, my prep work for next year is almost done, I've logged some decent running K's, and the roads were fairly dry (well the paved ones were, the dirt roads were pretty muddy). Might as well embrace some pain and get this test done. Here's the numbers:

0-10 minute mark: distance: 2.51k heartrate: 181 bpm
10-20 minutes: distance 2.54k heartrate: 183bpm
20-30 minutes: distance: 2.49k heartrate: 183 bpm
Average heartrate for last 2o minutes: 183 bpm.

So my LT is 183 bpm. I was able to maintain pretty much the same pace throughout and by the end I was sucking wind pretty hard. I believe I got an accurate reading, which is what matters. So what does this number mean? Well from my LT we can determine correct trainings 'zones', (using Joe Friel's method)

Zone 1: easy / recovery workout: <155
Zone 2: endurance training: 155-164
Zone 3: 'intensive' endurance training: 165-173
Zone 4: Threshold training: 174- 180
Zone 5 Threshold training 181-184

Personally I think these values are a little on the high side, maybe 5 beats. I'll experiment during my 'build phase' and zone in on what I think is appropriate - but at least it gives me a starting point.

So yesterday I ran through a speed trap and the officer clocked me at 13kph. Now I 'know' I was only at a max of 12 kph, my internal speedometer is quite accurate I assured him. However, he'd have none of that as his laser thingy clearly clocked me at 13kph. Fortuneately, it was a 40 zone, so I didn't get a ticket. Luckily I was just 'warming up' and he'd didn't catch me during Tuesday's LT test. :)
Cheers!

2 comments:

Cliff said...

Darren,

I was chatting with Mike Rucci (www.D3Multisport.com ) and he say run a 10 k pace and finish it off with a 5 k pace.

Would u be doing a LT test for your bike as well?

Darren said...

Hi Cliff,

I think that's a good pacing recommendation. You want to be pretty well gassed at the end of the test.
I found the test difficult. Doing Zone 1 stuff for 3 months, then jacking up the system for a 30 tt = sore muscles. Yea, I'll be doing a LT test on the bike at the end of the month.