LACTIC THRESHOLD
Ok, i need some help. I got into a discussion last night with a very avid cyclist. He said we have to test on heart rate to establish our lactic threshold. We in EN never talk abour lactic testing. I told him that it is all about watts which equals "work:" From my limited understanding of how it all works, it looks like we are going to go into race knowing what watts we are going to hold for 112 miles and then we will know what pace we are going to run. He kept drilling me on how i estaablished my zones within the data tool with out doing a lactic test. Will we ever do lactic testing or is everything going to be off our watts and pace. I also understand that we are never going to be close to the line of lacticte threshold during the ironman, and maybe this is why we dont test.. Please help
Comments
Hi Shawn,
You will determine heart rate training zones at the same time as pace/wattage training zones. When you do our tests. Notice that we have you do time trial (bike and run), and have you enter your time for the run, watts for the bike (if you have a powermeter), your average heart rate for the run TT and average HR for the bike TT. This average HR for the TT's is a close approximation of your lactate threshold heart rate.
From the run time you extract a VDot value and prescribed run paces.
From the bike watts you extract an FTP (functional threshould power) and we then prescribe wattage for bike workouts as a percentage of FTP.
From the bike and run average HR's for the TT's, we determine heart rate training zones -- the Zone 1-5 stuff you see in the prescribed workouts.
But to answer your friends question:
Heart rate is your body's response to the work performed. When you run 8' pace or ride your bike at 220w, your body is performing the work required to move your body down the road at 8' pace or to push 220w. Increased fitness (becoming more fit and running a 7' mile, or pushing 260w) is a fuction of your body adapting to sustain higher and higher workloads.
Pace and watts are objective measurements of the work performed by your body. Your body then dials up a heart rate to support this work performed...it's a response, not a direct measurement of the worked performed. More importantly, heart rate is subjective -- 8' pace/220w could yield a 165bpm heart rate on Tuesday, but only 160bpm (or 170bpm) on Thursday. But 8'/220w on Tuesday is always 8'/220w on Thursday.
In summary (not sure if I'm being clear here
):
The net is our "EN motto," displayed across the back of our jerseys and singlets: Work is Speed Entering the Body -- focus on the work, put weight on the bar and lift it, and you will get faster.
If you have power, ignore heart rate for testing purposes. The difference in heart rate between days may be fitness as you noted, but it could also be a whole host of other factors like dehydration or fatigue. You just don't know. As Rich stated, the power meter measures work, the heart rate monitor measures your response to that work on that given day.
As to terms, lactic threshold or functional threshold, to most they mean the same thing and are used to benchmark fitness levels and to help set training zones to aid in training. On the bike the most precise test is the amount of power that can be generated in one hour, which is your functional threshold. Most people approximate this test with a shorter version. EN uses the 2x20(2) test. Many use a 20 minute test and extrapolate results. The run test is typically a 10K race result, but again you can use 5K results or other tests. By testing at the beginning and end of a block you have objective evidence that you have improved your fitness.
Work works! Good luck bud.
I used power only for all training and racing last season. When I got to my first A race, the weather had shot up by about 20 degrees. I held the target power on the bike for the most part, and did not back off the power to compensate for the heat. Mistake. I think if I had an HRM, I would have had a better indication that my body response was not correlating with my power output (as I had in cooler weather training). In light of that experience I am going to do some experimenting with the HRM and power meter together this season.
Totally agree. HR, RPE and other inputs are great secondary pieces of information that should not be ignored when racing. If your HR is too high it becomes very hard to ingest and digest food, it's a sign of dehydration and fatigue. If your HR is high, it doesn't necessarily mean you need to slow down, maybe it's just drink more. If it's 100 degrees outside, it's probably worth considering. Also as often is the case, your HR may be very high coming off the swim and onto the bike. In this case, it's often best to slow down, get the HR settled and get food and liquids into the system.
To my original point though, sitting on your trainer and trying to build fitness, power is best, everything else is secondary.
tom