Heart Rate Monitor Buying Guide

How heart rate monitors work

Heart rate monitors, while useful to anyone who is exercising or wants to exercise, are particularly recommended for two groups of people: those with medical conditions who need to keep their heart rate down and competitive athletes who use heart rate monitors as a training tool. If you’re just starting an exercise regimen, you can use a heart rate monitor to establish your endurance limits and monitor your progress. Heart rate monitors can also help dieters determine how many calories they burn during a workout.

Heart rate monitors have one basic function: measuring your heart rate. How you use that information is what gives a heart rate monitor its value.

For a heart rate monitor to be a useful part of your exercise program, you need the ability to set your target heart rate (THR). This is the heart rate you want to maintain during exercise, and before you can determine that, you need to calculate your maximum heart rate (MHR). MHR is the number of times your heart can beat in one minute and it represents the absolute maximum physical exertion you can endure.

THR is a percentage of your MHR and is usually expressed as a target zone consisting of your THR +/- 11 heartbeats. For example, if your MHR is 190 and you want to exercise at 70% of your MHR, your THR is 133 and your target range is 122–144.

Goals

Heart rate monitors range from the very simple to the enormously complex, so before you buy one you need to determine your exercise goals. If you’re just beginning an exercise regimen or just trying to get into better shape, a basic heart rate monitor without advanced capabilities would be best for you. If you’re trying to lose weight, look for a heart rate monitor that can calculate the calories you burn.

To get the best value, think about your future fitness plans as well as your current goals. Once you get rid of that extra weight and reach your desired fitness level, do you think you might train for competition? If so, choose a heart rate monitor with tracking tools that you can use as you need them.

Ease of use

Most heart rate monitors consist of a chest strap that serves as a transmitter and a wrist monitor that serves as the receiver. Using electrodes that contact your skin, the chest strap measures your heart rate and transmits that information to the wrist monitor. It’s essential for a heart rate monitor’s chest strap to fit properly—snug, but not constricting. If the strap is too loose, proper contact cannot be maintained and readings will not be correct.

Because the chest strap is almost universally considered cumbersome and somewhat uncomfortable, some heart rate monitors do away with it, but the results so far have not been good. One strapless model uses fingertip sensors on the wrist monitor, but user feedback so far is that it is difficult if not impossible to keep your fingers on the sensors during most workouts. Another heart rate monitor uses a modified glove with fingertip sensors built in, but this model can only be used at temperatures above 60º Fahrenheit and can’t be used at all for swimming or cycling.

Heart rate monitors that simply monitor your heart rate and calculate calories burned have few, if any, buttons to master. Adding features means more screens and buttons to contend with, which can be inconvenient during a workout. Choose a heart rate monitor with your goals firmly in mind and don’t buy more than you need.

Features

Most heart rate monitors have an alarm that alerts you when you go over or under your THR. Some will store your heart rate information for future reference. More advanced heart rate monitors keep track of not just your heart rate, but lap times and time spent in your THR zone as well, allowing you to monitor your progress as you train.

Serious athletes should choose heart rate monitors that calculate the average heart rate over an entire exercise period and gauge hydration levels, glycogen stores, recovery, race pace and fatigue. These heart rate monitors should also let you track your training goals over time. The most advanced heart rate monitors will maintain a detailed log that you can download to your computer so you can track your performance over longer periods of time.

Other considerations

Athletes and trainers will tell you that a heart rate monitor is only one tool to help you while you’re exercising. As valuable as a heart rate monitor is for training, the most important thing is to listen to your body. Pay attention to how you feel as you work out, and from workout to workout.

Heart rate monitors use radio waves to send your heart rate information from the transmitter to the receiver. In certain circumstances, such as when someone near you is also using a heart rate monitor, their radio signals could interfere with yours, causing a false reading. Electro-magnetic fields can also cause interference. If you work out near power lines, you could also receive false readings. This issue, common to all radio devices, is called cross talk.

Some heart rate monitors require a return to the manufacturer for battery replacement. This may be unavoidable if you’ve got your eye on a particular model, but if not, look for a heart rate monitor with a replaceable battery you can find easily.

Need to know more?

• Heart Rate Training Basics
  http://www.howtobefit.com/heart-rate-basics.htm
• Heart Rate Monitor Training
  http://www.marathonguide.com/training/articles/HeartMonitorTraining.cfm
• Understanding Target Heart Rates
  http://www.americanheart.org/presenter.jhtml?identifier=4736