If you’re new to exercise and looking to start a new training program, you may be wondering what intensity level is appropriate for your goals and fitness level. Many people are unsure of what intensity levels are defined and avoid exercises labeled vigorous intensity due to fear of injury or lack of capacity. As a personal trainer and exercise physiologist, it is my job to help explain these terms and concepts in a more understandable way. In this article, I’ll break down light, moderate, and vigorous intensity so that you, as a physically active individual, are more educated and more comfortable with what you are doing in your day-to-day exercises. It is recommended that most healthy adults engage in a combination of moderate and vigorous exercise, while light to moderate exercise be performed by the physically challenged. Intensity is individually based, which means your intensity level is based on your physical abilities and is not generalized by the abilities of others. Ideally, a professional in the field would determine your intensity levels based on a guided fitness test, but I will provide you with information that will allow you to obtain an estimate without such resources. For this we will use what is known as the target HR reservation method. This method starts with HR reserve, which is defined as the difference between your resting heart rate and your maximum HR. Your heart rate reserve is then multiplied by the appropriate intensity percentage you’re aiming for, then your resting heart rate is added again to get your target heart rate reserve. Below, I have demonstrated the method for moderate intensity exercise.
1) To find your HR max. Estimated, subtract your age from 220.
220-22 = 198 bpm. My estimated maximum HR is 198 beats per minute.
2) To find your resting heart rate, use a radial pulse or heart rate monitor. My resting HR is 60 beats per minute. I will now subtract my resting heart rate from my estimated maximum heart rate to determine my heart rate reserve.
198 – 60 = 138 beats per minute.
3) Now I must use the heart rate reserve (HRR) and multiply it by the percentage equivalent to the intensity you intend to achieve.
to. Light intensity <50% HRR
B. Moderate intensity 50-70% HRR
vs. Vigorous intensity 70% -85% HRR
In this case, I would like to exercise at a moderate intensity. So I will multiply my HRR by 50% to get my lowest HR value and then by 70% to get my highest value to stay within that moderate intensity range.
138 beats per minute X.50 = 69 beats per minute.
138 beats per minute X.70 = 96.6 beats per minute.
4) The last step in this process to obtain your final target HR reserve range is to add your resting HR to the HRR percentage. This allows the equation to consider your level of cardiovascular endurance at rest and adjust accordingly. Below I have demonstrated how to do it and have found my target HRR range for moderate intensity exercise.
69 beats per minute + 60 beats per minute = 129 beats per minute
96.6 beats per minute + 60 beats per minute = 156.6 beats per minute.
Target heart rate range for moderate intensity = 129 bpm – 156.6 bpm.
Benefits of light intensity exercise
Light intensity exercise is very beneficial for older adults. It allows them to remain physically active when there may be physical limitations or health problems that prevent moderate or vigorous activity. Light intensity is considered to be anything below 50% of the target heart rate reserve and provides many health benefits, especially for the unfit. An Oregon State University study, published in the American Journal of Health Promotion, showed a significant increase in the health of older people, who participated in light physical activities such as walking. These individuals were less likely to develop chronic diseases and had lower body mass index measurements.
Benefits of moderate intensity exercise
Moderate intensity exercise is the most beneficial form of exercise. It produces a huge number of health benefits ranging from lower blood pressure, improved cholesterol, weight control, cancer prevention, and much more. A moderate intensity is recommended for all adults unless restricted by a physician. Moderate intensity is anything between 50% and 70% of your target HR reserve and can be achieved by doing many activities, including brisk walking, biking, water aerobics, and dancing. There are a wide range of ways you can be physically active and reap the benefits of moderate intensity, but it starts with you taking the first step.
Benefits of vigorous intensity exercise
Vigorous intensity exercise is recommended for adults who are typically physically active and of at least an average level of fitness. Vigorous intensity is not weightlifting or Olympic-rate sprinting. Intense intensity activities include jogging, rowing, elliptical, fast dancing, and aerobics. The target HR reserve percentage is between 70% and 85%. It is recommended that, if you have a history of health problems or are middle-aged, obtain authorization from your physician before engaging in vigorous activity. Vigorous intensity has similar benefits to moderate intensity, but it also carries an increased risk of injury. It is recommended that the average adult obtain a combination of moderate and vigorous intensity to achieve the maximum benefits from exercise.
Now what?
In conclusion, it is useful to know that intensity levels are important but not as intimidating as they seem. The ACSM recommends that a healthy adult get 30 to 60 minutes of moderate exercise or 20 to 60 minutes of vigorous exercise, or a combination of both, each day for ≥3 to 5 days a week. It is also recommended that if you only participate in moderate intensity, you do it 5 ≥ days a week and if you only participate in vigorous intensity, 3 ≥ days a week. Ask your doctor if you have any concerns about your current fitness level and your ability to engage in vigorous intensity exercise. I hope you can take what was mentioned above and use it as a resource on your journey to optimal wellness.