First, I haven't officially calculated my heart rates since, well, ever. The last time I had planned a test was during a race in 2010. I had pre-programmed my Garmin for the race, including transitions. Unfortunately, the multisport function crashed the device requiring an update on the firmware (which at the time was not available). I could get a display but not record any data. I ended up guessing at my lactate threshold based on the few times I glanced at the device. I estimated my LTHR at 171. Using the chart provided by Friel in his Triathlete's Training Bible. Here's a link to his blog, lots of good stuff there. I extrapolated my zones. There were 2 issues with the system: the estimated LTHR and technically your are not supposed test during a race. Second, I am Un-American and need something to do during the Superbowl.
I think that my zones are too high. This is further supported by my Rate of Perceived Exertion (RPE). While biking, I feel a shift in energy around HR 150, when, according to the data, it should happen at 153. Minuscule difference, sure, but I still want to know.
1. Queue up a testosterone, laden mid-80s combat movie (Commando)
2. Warm up. I did 4x2:30, increasing gearing. Then 5x(1 min hard/ high cadence: 1 min spin). 5 min easy Z2 spinning.
3. Pee. Hydrate. Reset watch. (It's best to do this off of the bike)
4. Start spinning and bring HR into Z4. Start watch again.
5. Ride as hard as possible for 30 min. At the 10 min mark, hit lap. Stop timing at 30 min.
6. Spin comfortably for 20 more min.
7. Laugh at cheesy special effects and one liners by the Arnold (whom I believe is a triathlete)
8. Limp off bike holding hamstring.
The hypothesis is refuted. My former LTHR was 171. According to the results of this test, it is 172. My zones do not change more than one heart beat. My next test, try and figure out why I am such a pansy at HR 150. Not sure how to measure this yet.