Let’s return to our fictional scenario presented in the previous blog – you are finishing up physical therapy following your total knee replacement and are looking to maintain your gains by independently exercising at the gym. In our last post, we discussed some of the reasons people frequent the gym. While there are a wide variety of motivations, the key takeaway should be that exercise is a personal construct and is a reflection of one’s goals for the effort they put in. With that information in mind, this next installation outlining transition from PT to the gym will address some of the key ideas one should be familiar with in order to maximize your time spent.
The fitness and health industry can be a chaotic place. It sometimes seems like there are a multitude of different people endorsing a multitude of different products and promoting a particular approach to fitness. Sometimes these endorsers make wild claims such as “lose 100 pounds in 10 minutes with our new HYPER-FAT-BURNING HIGH INTENSITY METABOLISM BOOSTING TAI CHI INSPIRED WORKOUT PROGRAM (for 10 easy installments of $9.99… plus shipping).” Others make such claims as targeted fat loss in particular areas of the body and the power to get you in the shape of your dreams in just weeks. While there are nuggets of truth present in many of these claims, they consistently seem to breeze over the bottom line – any increase in physical activity beyond your baseline level of activity will yield results when done to an appropriate intensity. The common theme among these different programs is that they promote exercise. Plain and simple.
Does this mean that all exercise is equal? No, it does not. As we discussed above, exercise is a highly individualized construct that needs to factor in the individuality of the participant. Some folks are unable to tolerate high intensity exercise due to cardiovascular compromise, but are very comfortable with a long bike ride on a recumbent bike. Others might be able to participate in high intensity exercise program from an intensity standpoint, but may have joints that groan in protest when performing the higher impact, ballistic movements. All exercise is not equal, but exercise as a whole is the way to elicit the positive changes in health most people seek when appraising different programs.
To help you navigate the various forms of exercise and programs, some key terminology is presented below for reference. This is not meant to be an exhaustive list, but rather a quick glossary of some commonly used terms.
Physical activity -> according to the American College of Sports Medicine (ACSM), physical activity is ANY bodily movement produced by muscular contraction and relaxation that demands an increase in calorie requirements well beyond baseline resting levels. This is a deliberately broad definition that encompasses anything from running sprints to running through the grocery store to get dinner in the oven before the kiddos come home from soccer practice. Other good examples would include vacuuming the house, carrying and folding laundry, and walking from the parking lot to the Physical Therapy Specialty Center for your next PT session. Not all physical activity is considered exercise, but all exercise would be considered a form of physical activity.
Exercise -> according to the ACSM, exercise is a type of physical activity that involves planned, structured and repetitive bodily motion with the expressed purpose of maintaining or improving aspect(s) of physical fitness. The key difference between exercise and physical activity is in the planned and deliberate nature of exercise, versus physical activity which does not need to meet this criteria and is broader in scope.
Physical fitness -> while the definition can vary based on the source, the ACSM defines physical fitness as the ability to carry out daily tasks with vigor and alertness, without undue fatigue, and with ample energy to enjoy leisure pursuits and meet unexpected emergencies. Broadly, this includes health-related concepts such as cardiovascular health, cardiorespiratory endurance, muscular strength, muscular endurance and flexibility. There are some skill-related ideas here as well – agility, coordination, balance, power, reaction time and speed chief among them. Both the skill and health related ideas require the same thing to be developed: PRACTICE. Physical fitness can be viewed as the result of physical activity and exercise performance.
SAID principle -> this is an acronym that translates to Specific Adaptation to Imposed Demands. In a nutshell, the SAID principle states that different types of exercise will yield different outcomes with respect to features of physical fitness. Engaging in marathon-distance runs will cause different adaptive processes to occur within the body compared to, say, power lifting. One will lead to advancements in realms such as the body’s use of aerobic metabolism (long distance running) to maintain a sustained effort, while the other will induce improvements in the anaerobic metabolic mechanisms (powerlifting) to generate rapid, forceful movements. The type of exercise an individual chooses to participate in will have a large part in how their body changes both on a macroscopic level (i.e body shape, muscularity, speed, etc), but also at a microscopic level where we see changes in things like muscle fiber types, mitochondrial density and efficiency of neuromuscular movement control. We had said earlier that not all exercise is equal, and the SAID principle is a good way of conceptualizing the truth in that statement.
Exercise volume -> this idea refers to the cumulative amount of exercise performed over a given amount of time. This can be expressed purely as a number (repetitions, sets, weight, distance ran, etc) or as a metaphorical representation of the exercise performed if quantifying into numbers is not possible. As an example – if our hypothetical patient performed 30 repetitions on the leg press at 100 pounds (that is 3 sets of 10 repetitions), he performed 30 x 100 = 3,000 pounds of volume on this exercise. Another example – if our hypothetical patient spent his entire 8 hour work day lifting packages and loading Amazon trucks nonstop at a rapid pace, this would be a high volume day. Comparatively if he spends his first 4 hours doing the same intensity and the next 4 at half the intensity, he will have reduced his overall exercise volume by approximately 25%. If he works only a half day but busts his butt the entire time, he has reduced his typical exercise volume by approximately 50%. This is imprecise, but useful for ballparking exercise volume if numbers can’t be used. There are a plethora of ways to manipulate training volume and we will discuss further when these definitions are brought together in a sample case.
Exercise frequency -> this idea refers to how often in a given amount of time exercise is performed. As an example – if our hypothetical patient were to go to the gym 1 time per day, 3 days per week with a rest day between, the exercise frequency would be 3 days per week on alternating days with weekends off. This idea will become more important later in our discussion as we talk about exercise dosage.
Exercise day selection/ordering -> this idea is in reference to how one lays out their exercise days, rest days and the order in which they will be performed. There are numerous schemes for organizing their exercise schedule – some folks go 6 days per week and rest only on Sundays, while others prefer 3 days per week with weekends off and a rest day between each exercise day. There is no wrong answer here; exercise scheduling must take into account personal factors and the physical ability of the individual in question.
When looking to begin or continue an exercise regimen, it is useful to consider the above ideas to break down the aims and execution of a given program. A program should be analyzed with respect to not only how often it asks the participant to exercise, but what aspects of physical fitness it purports to improve and if this matches with the individual’s goals for themselves. In our next segment we will take a deeper dive into the finer points associated with exercise intensity, program design and rationale for choosing particular modes of exercise versus others. Until then – stay healthy, safe and happy!
- Dorian Campisi, PT, DPT