Heart Rate

A great technique for training that has become popular recently involves the monitoring of one's heart rate.  For team training, this technique is used less since practices need to be more uniform for everyone for efficiency.  But for individual training, monitoring the heart, in conjunction with actual speed and perceived effort, can be a huge training aid.  Below we have listed some of the basic considerations of using your heartbeat to enhance your training.
 

Don't.  Don't estimate your maximum heart rate by using your age!  This is ridiculous.  True to our motto, we know that every athlete is different, and that grouping athletes together by a category like age is cooky.  Some people that are 50 have higher maximums than those that are 40 or lower.  So many variables play a part is what your maximum heart rate is, that estimating by one factor may give you an incorrect level.  Maximum heart rates can also change for the better or worse depending on the level of conditioning at any given time.  If you want to be lazy about it and aren't looking for a precise level then use the age method.  Otherwise, stay away from it.

Do.  Look at the change in your heart rate at different work levels.  The chart below gives you a rough estimate of what your rates should be based on a given exertion level;

  Effort Max Heart Rate Blood Lactate
12 Max 100%  
11      
10 Very Hard   High
9   90%  
8 Hard   Med
7   80%  
6 Mod Hard   Med/Low
5   70%  
4 Easy   Low
3      
2 Min    

As an example of how to use this info, suppose you ran for 15 minutes at the Medium Lactate (perceived) pace, and at the end you determined that your heart rate is 160 beats per minute.  Your maximum heart is then likely to be around 188 beats per minute (160/.85).  A non-mathematical way to get your maximum would be to run at a moderate to easy pace for 5 to 10 minutes and then sprint as hard as you can up a hill for 3 to 4 minutes.  Take your pulse, and that should be your max.

And, if you also knew that you went a 7:00 pace you could judge your improvement by monitoring future runs.  You may see a small rise in your heart rate to 163 and an increased pace of 6:20 while you are still running at a Medium pace.  Similarly, you may try to run an identical pace of 7:00 and realize that your effort and heart rate have dropped.  These would both illustrate a rise in your threshold and, in turn, your performance.

If, however, things are going the other way, where you feel as though you are working harder and you cannot increase your heart rate or drop time, give yourself a rest, since you are not helping your training out by continuing--you are likely over-trained and/or not rested enough.  The chart below gives you examples of what to look out for;

Set

Perceived Exertion

Heart Rate

Time

It Means
1st Hard 160 10:00  
2nd Mod/Hard 155 10:00 Increased Threshold
2nd Hard 165 9:45 Increased Threshold
2nd Harder 155 10.15 Over-trained, sick, stressed, etc.

Once you get a feel for your heart rates you should be able to better gauge and adjust your training to maximize the results.  Be sure to note over-training and under-training signs, and possible clues that you are sick or stressed and adjust your workouts accordingly. 

Other Factors.  Heat can reek havoc on your body, because when the body gets hot, it diverts much of the blood to the skin to help cool your body.  That is a great thing, except for the fact that it leaves less blood for the rest of your body.  As a result, your heart pumps faster to compensate and your lactic acid builds up quicker.  Also, if your heart rate rises by more than 10 beats per minute while working just as hard, you may be becoming dehydrated.  Get yourself some fluids quick!  A 10% decline in your performance at the same effort could also signal troubles.

Keep yourself full of carbos.  During a long workout or race, if you notice a drop in speed and in heart rate, but you still feel like you are working just as hard, you may be 'bonking' or 'hitting the wall'.  This could be a result of not taking in enough carbohydrates to keep your muscles going.  If your heart rate just won't go up, then get yourself some carbos in the form of either a good sports drink or some sport gel or bar.  However, if you take these after you hit the wall, it is probably too late.  Do it well before you think you might be getting depleted and do it often.

Keep in mind that if you have been partying too much or are stressed, your body may also show abnormal signs of strain.  Listen to your body and adjust your workout accordingly.