• Basic cardiovascular physiology
• Pros and cons of using a heart rate monitor
• Definitions
• Calculating your maximum heart rate
• Heart rate training zones
• Training tips using a heart rate monitor
• Resting heart rate
• Search for the heart rate monitor for your needs

BASIC CARDIOVASCULAR PHYSIOLOGY

• the heart (the pump)
• the arteries (a distribution system)
• the capillaries  

   

  PROS AND CONS

   
   (the exchange system where gases, nutrients, and other chemical compounds move to and from surrounding tissue
• the veins (which are the return circuit)

With physical activity (exercise) more oxygen is required by the muscle cells, and the circulatory system responds by increasing the heart rate (and the cardiac output). With aerobic training, the actual amount of blood pumped per heart beat (stroke volume) increases and the efficiency of the exchange process at the capillary level improves. The result is a lower heart rate for any level of physical activity in the trained versus the untrained individual. Thus aerobic training benefits include:

• a lower resting heart rate
• a lower heart rate for a specific level of exertion
• an increased exercise capacity at an individual's maximum heart rate.

Let's look at the pros and cons on the use of a HRM.

The ADVANTAGES of a HRM include its use:

• as a motivational tool - like a coach ; brings objectivity to a training program.
• to teach beginners to read their bodies and avoid anaerobic overtraining.
• to aid in doling out energy during time trialing or climbing, saving some for the final effort.
• to analyze race efforts and design a personalized training program.
• to spot overtraining (heart rate 10% higher than normal on awakening for several consecutive days).

• its inconsistency - at the same heart rate you're not always putting out the same effort day to day.
• the lack of scientific support - there is no evidence training with a HRM improve competitive performance.
• too much data, esp with elaborate HRMs, with little agreement on how to use this information to improve training or performance.
• the lag time in heart rate response to a change in exertion - 15 to 30 sec lag with 2 to 3 min to stabilize at the new level of exertion.
• its incompatibility with group training.
• it distracts from dangerous road hazards.

DEFINITIONS

Here are some definitions you'll encounter in the literature on heart rate monitors:

• bpm - beats per minute
• Max HR (MHR) - maximum heart rate (expressed in beats per minute)
• target heart rate - the training heart rate (usually a range of values)
• Anaerobic tthreshold (AT)* (synonymous with lactate threshold). Lactate production occurs with muscle cell activity and increases as activity becomes more vigorous. Lactic acid is metabolized by the muscle cells, but at some point they cannot eliminate (or oxidize) the lactate as fast as it is being produced and the blood lactate level begins to increase. In trained athletes, this threshold for lactate buildup occurs at a higher activity level or percentage of the athlete's MHR or aerobic capacity. For all practical purposes, the AT is the highest heart rate you can maintain for a race or hard ride lasting up to an hour. As the AT increases with aerobic conditioning, it is considered one of the standard measurements to track training. The AT is usually reached at 80-90% of your maximum heart rate, but in elite riders rises to 90-93% of their maximum heart rate.
• lactate threshold (LT). See anaerobic threshold.

Let's assume you have decided to use a heart rate monitor in your training program. The first step is calculating your MHR or maximum heart rate.

CALCULATING YOUR MAXIMUM HEART RATE (MHR)

Just as we all vary in height and body habitus, everyone has their own personal maximum heart rate genetically "hardwired". Our maximum heart rate also decreases approximately one bpm (beat per minute) per year. The average MHR of a teenager is 220 beats per minute, but this may vary +/- 11 beats from the average (209-231 bpm). For example, a 40 year old who would be expected to have a MHR of 180 (220-40) could vary from 169 to 191 for his or her own personal MHR.

Another Key point is maximum heart rates are "sport specific" i.e. they vary from one sport to another. For a given rate of oxygen consumption, weight bearing activities such as running raise the heart rate more than cycling (part of your weight is supported by the bike). So you cannot use your maximum heart rate from running to plan a cycling training program without risking overtraining.

One of the following two approaches can be used to determine your MHR for cycling. The first is more accurate and the one I prefer. There can be marked discrepancies between the estimated MHR and real life results (up to 5% of the population can have heart rates 20 beats above or below the ESTIMATED figure). And if you are in shape, the typical decline of one beat per minute per year doesn't always hold.

• Warm up thoroughly. On a long, steady hill increase effort every minute for at least 5 minutes until you can't go any faster. Then sprint for 15 seconds. Check your heart rate at its maximum for a full 30 seconds and double the number. Similar results can be obtained on a stationary trainer.

   

• 220 minus your age in years. A rough figure and much less accurate than the on bike approach.
  
• The only limit to the length of time one can ride at 100% of their MHR is personal discomfort. This level of activity does not "strain" the heart muscle or have other harmful effects on the heart itself. Although this level of activity might be considered in a competitive race or event for a short sprint, maximizing the benefits of a training program is the result of a mixture of recovery and hard days (see below). As the time you can hold 100% MHR is considerably shorter than the time you can ride at 84-90% MHR, the art of racing is finding the right mix to get you to the finish line first. Most competitive athletes train at their lactate threshold (84-90% of their MHR).

HEART RATE TRAINING ZONES

The Heart Rate Intensity Zones are divided as follows:

• Zone 1 65% of MHR (recovery rides)
• Zone 2 65-72% of MHR (endurance events)
• Zone 3 73-80% of MHR (high level aerobic activity)
• Zone 4 84-90% of MHR (lactate threshold(LT,AT); time trialing)
• Zone 5 91-100% of MHR (sprints and anaerobic training)
• If you always train at low heart rates, you will develop endurance with no top end speed. Conversely if you train hard most of the time, you'll never recover completely and chronic fatigue will poison your performance. The solution is to mix hard training with easy pedaling in the proper proportions.

The best approach is to stay below 80% of maximum heart rate (zones 1 to 3) on your easy days to build an aerobic base while allowing day to day recovery, and then push above 85% when it's time to go hard to improve your high level performance. But avoid training in the no man's land or mediocre middle at 80-85% of MHR where it's too difficult to maintain the pace for the long rides needed to build endurance and allow some recovery time, but not hard enough to significantly improve your aerobic performance and increase your lactate threshold.

Training programs should be individualized, but once a good base is developed early in the season with Zones 1 and 2 exertion, most programs contain the following elements.

TRAINING TIPS USING A HEART RATE MONITOR

Tips for a training week: (see also mileage tips and training options)

• one long recovery ride - zone 1 or 2
• one long day (event distance + 10 to 20%) - maxhr = to that planned for the event
• three high intensity days - zone 4
• one or two interval workout days which are counted as one of the three zone 4 days. For example:
  • warm up - zone 1
  • 20 min - zone 3
  • 5 min - zone 4
  • 7 intervals - hit 90% max, recover to 60 - 65% max
  • 5 min - zone 4
  • 20 min - zone 3
  • warm down - zone 1
• the sixth and seventh days of the week can be rest days off the bike or slow recovery rides at zone 1 or 2 exertion to stretch out your muscles.

USING A HRM TO AVOID OVERTRAINING

1. Heart rate is higher than normal and legs feel tired
2. Heart rate is normal and legs feel tired
3. Heart rate is higher than normal and legs feel good
4. Heart rate is normal and legs feel good

In the first situation, your recovery from previous rides isn't close to what it should be. Head on home and take the day off. Pushing on will only put you in a deeper hole. In the second and third scenarios, your recovery is incomplete, but not to the extent of #1. You can continue riding, but only if you can keep distance and intensity moderate. Scenario number four indicates you are right on schedule with your training.

Your resting heart rate (RHR) is another indicator of your degree of training (and monitor for moving into an overtrained state). As you train, your resting heart rate should fallas a result of the increased efficiency of the circulatory system. The heart will increase the volume of blood pumped per beat, and the peripheral muscle cells will become more effective at extracting oxygen from the blood passing through their capillary networks. The RHR for an untrained individual is 60 to 80 beats per minute. With training, it is not uncommon to see the RHR fall into the high 40s or low 50s. And as mentioned above, regular monitoring of your resting heart rate in the mornings (before getting up and beginning your daily activities) can be used as a monitor for overtraining (heart rate on awakening and before getting out of bed 10% higher than your personal normal for several consecutive days).

SLOW HEART RATE

search for the best suited  heart rate moitor for your needs; ie  Running, Cycling, Triathlon etc.