As human beings, we need to exercise in order to maintain and/or improve our health and fitness. Yet, according to the Centers for Disease Control and Prevention (CDC), only 20.9% of adults (18 years of age and over) in the U.S. meet the Physical Activity Guidelines for both aerobic and muscle-strengthening activities. Only 20.9%! That’s almost disturbing. That means that out of approximately 240 million adults, only 50 million engage in adequate amounts of physical activity and exercise! This begs the following questions: 1) What are adequate amounts of physical activity and exercise?
2) What is the difference between exercise and physical activity? 3) Why are we seeing this trend?
What are Adequate Amounts of Physical Activity and Exercise?
The following statement is an excerpt from the American College of Sports Medicine’s (ACSM) most current Position Stand on the Quality and Quantity of Exercise:
“The ACSM recommends that most adults engage in moderate-intensity cardiorespiratory exercise training for ≥30 min-d on ≥5 d-wk for a total of ≥150 min-wk, vigorous-intensity cardiorespiratory exercise training for ≥20 min-d on ≥3 d-wk (≥75 min-wk ), or a combination of moderate- and vigorous-intensity exercise to achieve a total energy expenditure of ≥500–1000 MET-min-wk . On 2–3 d-wk , adults should also perform resistance exercises for each of the major muscle groups, and neuromotor exercise involving balance, agility, and coordination. Crucial to maintaining joint range of movement, completing a series of flexibility exercises for each the major muscle–tendon groups (a total of 60 s per exercise) on ≥2 d-wk is recommended. The exercise program should be modified according to an individual’s habitual physical activity, physical function, health status, exercise responses, and stated goals.”
Okay, lets break this down line by line.
Intensity may be prescribed as a percentage of an individual’s VO2max or VO2R, Heart Rate Max or Heart Rate Reserve (HRR), Rate Perceived Exertion (RPE), and/or Metabolic Equivalent (MET). The ACSM defines moderate-intensity as 50–70% of an individual’s HRmax and vigorous-intensity as 70–85% of his/her HRmax. Therefore, the ACSM is recommending that “most adults” perform cardiorespiratory exercise (e.g., LSD, Interval Training, etc.) for ≥30 min-d on ≥5 d-wk for a total of ≥150 min-wk, or vigorous-intensity cardiorespiratory exercise training for ≥20 min-d on ≥3 d-wk (≥75 min-wk ). They even suggest that a combination of these intensities can be performed so long as a total energy expenditure of ≥500–1000 MET-min-wk is achieved.
I know what you’re thinking; without a heart rate monitor, how do I monitor intensity? What the hell are MET minutes per week? Therein lies the problem! The governing organizations of the fitness industry (ACSM and NSCA) are providing recommendations that are irrelevant to the majority of the population. Most people do not want to invest in or wear a heart rate monitor, and even less are willing to learn what a MET is and track their MET minutes per week. So that leaves us with RPE. The OMNI RPE scale is a graphic utilized to help individuals identify their level of intensity. The scale ranges from “0” (Extremely Easy) to “10” (Extremely Hard). Two versions of the OMNI Scale are pictured below:
The OMNI Scale is probably the most applicable and relevant method to estimate intensity of exercise. How many times have you been in a conversation and been asked, or have asked someone, “On a scale of 1–10…” It is one of the most recognizable scales of all time. So why is it not more frequently implemented in the fitness industry? It is certainly easier to comprehend than percentages and MET-minutes.
In regards to resistance training, the National Strength and Conditioning Association (NSCA) and the ACSM recommend that individuals perform 2–4 sets consisting of 8–12 repetitions for each of the major muscle groups (e.g., Posterior Chain, Quadriceps, Back, etc.). Furthermore, these governing organizations suggest performing various flexibility and mobility exercises for each of the major joints at least two days per week. Obviously the NSCA and ACSM believe resistance training is essential to maintaining and/or improving health and fitness. However, these recommendations provided no insight into intensity, volume, or exercises. Yes, an individual could research resistance training and learn about percentages, sets and reps, and various methodologies and programs (e.g., linear and undulating periodization, Wendler’s 5/3/1, the Conjugate Method, HIIT, CrossFit, and split routines), but very few people are motivated enough to devote the time and energy necessary to learn the intricacies of resistance training. So, the question becomes, how do we better educate the general public regarding the specifics of strength training?
What is the Difference Between Exercise and Physical Activity?
The ACSM defines physical activity as any action or movement produced from the contraction of skeletal muscles that results in a considerable increase over an individual’s resting energy expenditure (REE). Exercise is a type of physical activity. What differentiates exercise from physical activity is that exercise is planned, structured, repetitive, and performed with the intent of improving and/or maintaining various components of physical fitness.
In order to simplify matters, I am going to use the follow definitions to differentiate physical activity and exercise:
Physical Activity — movement
Exercise — planned, structured movement performed with a purpose
Why is the Majority of Adults in the U.S. Not Meeting the Current Recommendations?
Possible explanations for the lack of engagement in physical activity and exercise include:
- Ineffective outreach, communication, and education regarding the frequency, intensity, duration, and mode of exercise (aerobic, anaerobic, resistance training, and flexibility) that individuals should perform
- Dull and redundant activities/training programs
- Lack of community, camaraderie, and/or competition in physical activity and exercise programs
- Perceived barriers (e.g., limited access to a facility, current fitness level not being adequate to engage in a new activity or program, lack of time, and cost of entry)
Research has suggested that there is a lack of association between knowledge of health and exercise and participation in physical activity. Thus, it is essential that we as exercise professionals develop new methods to influence and engage the public.
Potential solutions to increase engagement include:
- Identify and provide specific activities and modes of exercise
- Utilize the FITT principle in conjunction with the OMNI RPE Scale to generate more specific recommendations
- Incorporate as much variance as possible in regards to the activities and exercises
- Encourage participation in group activities, fitness programs, and sport in order to generate a sense of community, camaraderie, and competition
- Sponsor activities and events that are general, inclusive, and accessible to all members of the community
Next, we will discuss how to better implement the OMNI Scale and various other methods to estimate intensity, as well as how to improve the current training recommendations.