For several years I have been perched on the edge of the heart rate debate. Train with one or without one? Heart rate based training can be a powerful tool to increase your lactate threshold and enforce periodization...on the other hand, I think many ahtletes become overly dependent on their heart rate monitors. It's important to remember that your heart rate provides only a small picture of what is happening to you physiologically when you train. A number that is a bit "off" that day doesn't necessarily mean a bad workout. The heart is a muscle, too, and just like your quads and hamstrings, it has limits. It can get fatigued. Sometimes it needs a day or two to recover before it can rev back up to 90% of your max.
Anyway, enough of all that. I got one for Christmas, and I've been playing with mine for the past few workouts and having fun:
Sunday: Rode about 30 miles with one significant climb. At a comfortable working pace, it hovered around 144-146. During the hardest efforts of the climb, it got to 162. According to the monitor I burned about 1200 kcals.
Tuesday: Did some yoga in the afternoon. Downward Facing Dog: 75-80. Flank Stretch: Got up to 102. Corpse: 53. All others were about 82-84. Only burned maybe 80 kcals. Then went to my evening spin class: During the spin-up drill: got to 154. During the drill that came after that which was REALLY REALLY hard: got up to 159. During the sprint series: got up to 162. During each 3 minute recovery: got down in the 120's. During the 1 minute recoveries: lucky to get down to the 140's.
Thursday: Quick 2+ mile run. Comfortable working pace: 148-152. Did four 15 second pickups at about 80% effort: got to 159, 160, 161, and 162. Then did shoulder prehab: 120-130. Who knew.
Should pre-hab is another issue entirely, for another post.