Ok, here's a con to doing observed tests. I personally think they are a lot closer than a formula. I would also recommend that if you decide to do a climbing test, that you not do it alone. It isn't likely that you can have a problem if you've been exercising regularly. From what I've read about it, you will get to a pain zone before you injure your heart. Few people can "push" beyond that level. However, you will be on a hill and presumably clipped into the pedals and exhausted. A liittle support isn't a bad idea.
REPRINT:
Nevertheless, there's a flaw in anchoring your workout to your maximum heart rate. Few people know what it actually is. To learn it, you need to exercise at maximum intensity (red line zone) for 30 seconds or so and record your heart rate. Exercising at this intensity is hard. It's very uncomfortable. Even highly trained athletes can't spend much time there. Exercise at 90-100% of your maximum heart rate and you significantly increase your risk of injury. I often meet athletes who are willing to take the risk to do a self test. They have usually used a heart rate monitor and have pushed themselves to their limit in an attempt to learn how high their heart rate will go. They have a good sense of the stress their body will tolerate. They're used to pain for gain. They believe the benefits outweigh the risks. They know the value of anchoring their training to a true maximum heart rate. But even for those willing to put themselves through a max heart rate test the result can vary on any given day for any number of circumstances. Maximum heart rate is affected by heat, cold, altitude, dehydration, medication, stress, poor sleep, too much to eat. It changes as activity changes. Get my drift? The heart is the king of all the muscles. Its ability to beat a maximum number of times in a minute in response to internal and external changes and to adjust the body accordingly is awesome.
Finding Your Anchor
The good news is that you don't need a formula to design your exercise program and you don't need a reading of your maximum heart rate. You just need to know your heart rate at your anaerobic threshold. It's easy to find out with a 'talk test.' That takes a little bit of time and a willingness to exert some energy. If you have a heart rate monitor, this assessment will be easy. Here's how it works. Start walking to warm up your muscles. (I like the Reebok walking shoes best!) As you walk, attempt to monitor your pulse with periodic pulse checks (preferably using your heart rate monitor). You can also pay attention to your perceived level of exertion (sometimes called rate of perceived exertion). Here you use a scale of 1-10, then describe your pace as easy, fairly easy, medium, etc. using this range of numbers where 1 is very easy and 10 is very hard. After you are warmed up, increase your pace to an intensity where your perceived level of exertion or heart rate increases about 5 beats every 30 to 60 seconds. Pay attention to your breathing. When your pace is sufficient that you can't sing a song without taking a breath in a place where you normally wouldn't, check your heart rate. I encourage folks to have fun and learn to say Mary Poppin's phrase, supercaclifragilisticexpialidocious!! When they test for their anaerobic threshold, they know they've reached it when they can't repeat that word without taking a couple of breaths. That pace is what I call your 'functional' anaerobic threshold.
I believe knowing this 'threshold' number is much more important than knowing your max heart rate because it is the place at which your body shifts from aerobic (primarily fat burning) metabolism to anaerobic (primarily sugar burning) metabolism.
Whenever I work with a client, we determine this number and, for the purposes of designing a workout, look at a heart rate chart and find out where this number is on the 80% heart rate line. This may or may not truly be 80% of that client's maximum heart rate. But with that point as an anchor we can design a multiple zone (and multiple benefit) exercise prescription that will increase fitness and decrease fatness. We'll know we're doing wind sprints when the intensity goes above that number. Most deconditioned folks are encouraged to exercise only at 50-60% of an age predicted max heart rate. With this program they exercise just like everyone else.
There's more value to knowing this number. It's about motivation. Your heart has a resting point. It's the lowest number of beats your heart rate goes to at rest or the resting heart rate (RHR). The most accurate RHR is counted when you wake up in the morning before you sit up to get out of bed. You can get a pretty close approximation if you lie down and are still for ten minutes or so. Once you have your resting heart rate and your functional anaerobic threshold numbers, you can create a 'chart' that in relation to being dead (no heart rate at all) and your maximum heart rate (which you don't know) defines that range of exercise where the body prefers to burn fat as fuel.
(Heart Rate Chart)
With regular workouts that include 'wind sprints' above your anaerobic threshold, this number will not only go up, your resting heart rate (for most folks) will go down. If you create a graph like the one above you will be able to plot and see the changes in your fitness on a daily, weekly or monthly basis. We're talking major motivation here!!!
Heart Zone Training breaks this fat burning range and the two levels above anaerobic threshold into the zones described earlier. Believing 'you can only manage what you can measure' Edwards encourages you to spend a specific number of minutes in specific zones based on training goals. Each zone has points (1 for Healthy Heart, 2 for Temperate, etc.) which are multiplied by what she calls time in zone--the number of minutes you spend in each zone. Recording accumulated points validates your experience. It's an incarnation of Ken Cooper's point keeping system.