Given all of the variables, finding the correct pulse rate for a guy who runs on a treadmill can be somewhat of an adventure. With a proper understanding of your physiology, over-all fitness level, state of health, and what type of workout you are performing, you should be able to gauge your level of effort, and if you are in a safe heart rate zone. Also, because of the physiological differences between the genders, what works for a woman won't work for you.
Maximum Heart Rate
The first thing you need to do is calculate your maximum heart rate during exercise. Although the American Heart Association, or AHA, states that there is now a new gender-specific heart rate formula, the only real change affects women. Guys can still use the standard formula of subtracting their age from 220 for an approximation of their max heart rate. So if you are 50-years-old, your approximate max heart rate is 170 beats per minute.
General Training Zone
Referring to the AHA's target heart rate zone chart, you should stay with the broad range of 50 to 85 percent of your max heart rate, according to your age, as you do your workout on the treadmill. Using your age of 50 again, this means that you should be in the zone of 85 to 145 bpm as you workout. This is a very broad range for any man, but just remember that the harder you walk or run on a treadmill, the faster or harder your heart will beat.
Increasing Heart Rate
With the understanding that the heart will work harder as you increase your effort on the treadmill, be cautious to patiently increase over a period of time. As with most things, too much too soon on the treadmill will usually result in poor performance, possible injury and just plain not having any fun. As you increase your effort, knowing the different heart rate zones that apply to you can help. In a target heart rate chart for men, a 50-year-old man will be in the top end zone of 90 to 100 percent heart rate with between 153 to 170 bpm. Shorter periods of time should be spent in this zone until you can increase your fitness and effort safely.
Once you get a feel of where your level of fitness is during your treadmill workout, you can stray away some from the standard max heart rate formula to see what is right for you. Through experimentation by varying the time and effort of your workout, and how well you recuperate, you will be better able to see what works for you. Even though you may be 50-years-old, you may have been exercising consistently for a long time, which usually means you can sustain a higher max heart rate than what the standard formula tells you. If you have been sedentary for many years you may only sustain a heart rate much lower than predicted.
In an article on target heart rate zone training from Purdue University North Central, it is noted that by working out at a higher level of effort or overloading your cardiovascular system, the heart will slowly become stronger. Once the heart grows stronger from this work overload from your treadmill workout, it becomes more efficient. This new strength and efficiency will actually increase the max heart rate, and training zones, thereby allowing you to run or walk faster and farther without overly taxing the heart.