Function & Exercise
A well-rounded exercise program is the basis for an active life with high functional ability. A comprehensive exercise program includes strength, aerobic, and flexibility training. Such a program provides a margin of safety or physical reserve that is needed to reduce the risk of injury, for example falls or muscle strain from “overdoing it” in the garden. Physical reserve provides a buffer of fitness over and above that required for everyday activity. This buffer ensures a higher quality of life….staving off undue fatigue.
First and most importantly, exercise benefits our health. Without regular exercise, we are at higher risk for chronic (non-communicable) diseases, like diabetes, hypertension, cancer, obesity. More information on these benefits can be found at the following link to NIH Senior Health Exercise and Physical Activity Tips.
National Institute on Aging has published “Exercise and Physical Activity Guide”. This free resource is helpful if you are getting started on an exercise program. Think of your exercise program as addressing three primary areas, endurance (also called aerobic activity), strength (also called weight lifting, resistance training or strength training), and flexibility. Endurance activity should be a bare minimum of 30 minutes on 5 or 6 days of the week. This is the minimum needed to maintain good health. However, to have good physical function we need more endurance activity, and 10,000 steps a day is a common goal. A step tracker can help us become aware of how much or more importantly, how little walking we’re doing. We should all pick the endurance activity (walking, swimming, cycling, hiking, to name a few), that we enjoy.
Walking improves function and reduces the risk of disability.
In a scientific trial where women were randomized into two groups, a control and a walking group, the walkers met 3 times/week for 6-months and walked for 1-hour (Moore-Harrison et al., 2009). The control group met to discuss nutrition. At the end of the 6-months, the overall fitness (aerobic capacity) of the walking-exercise group improved by 17% (see Figure 1). This was 35% better than the control group. The control group lost fitness so that by the end of the 6-months, the walking-exercise group was 35% more fit than the control group.
The walking-exercise also increased the groups’ overall physical function. Physical function, measured using the CS-PFP, improved by 25% whereas the control group did not lose function as illustrated in Figure 2. Risk of disability decreased from 42% to 25% in the walking-exercise group. The walking-exercise group increased both their overall fitness and physical function also increasing their physical reserve. The non-exercising control group lost fitness but not physical function, meaning they drew down their physical reserves.
Strength training is an effective means to build physical reserve and improve overall physical function.
This has been found in multiple scientific randomized control trials, in older adults (Cress, et al., 1999, Miszko et al., 2003), in people the heart disease (Ades et al., 2003, Brochu et al., 2002, Savage et al., 2011, Gary et al., 2012), and women with fibromyalgia (Kingsley, et al., 2005). In a study of women who exercised for 6-months with both aerobic and strength training, the exercise group improved overall physical function (CS-PFP total) while the control group remained essentially the same (Cress, et al., 1999). When physical function is measured using the CS-PFP, we can also learn about physical function in the different areas, upper body strength (UBS), upper body flexibility (UBF), lower body strength (LBS), balance and coordination (BalC) and endurance (End). In Figure 3 below, the 14% improvement in overall physical function was due to the improvement in both the upper and lower body strength and endurance. These reflect the type of training the women did, strength and endurance. The improvement in balance and coordination was a by-product of the overall training program. The exercise group carried 14% more weight and did it 10% faster after the training period. The exercise program improved their physical reserve providing benefits that were reflected in everyday life.
Functional training is classified as exercise training that is designed to intentionally improve function in activities performed in daily life (Wikipedia, 2017 https://en.wikipedia.org/wiki/Functional_training). The interventions that have used the CS-PFP to assess exercise training were designed to improve daily function. A mistaken notion is that “living in a two-story home will keep me fit enough that I do not have to exercise.” “Gardening is my exercise.” These are mistaken because they look to everyday activities as being adequate to provide the fitness necessary for maintaining physical reserve. Vacuuming, window washing, and gardening are not exercise programs. These are activities that require fitness but are not adequate to build fitness. An exercise program will be systematic, of moderate to high intensity, and a duration to improve cardiovascular and muscular fitness and flexibility. As a species, our ancestors survived by being efficient in their overall daily function whether food was from agriculture or as a hunter-gatherer. As we perform everyday functional tasks, we are programmed to do this in the most efficient manner possible, expending the least amount of energy. Whereas, systematic exercise is designed to make the activity (exercise) progressively more difficult in order to build fitness. This relatively brief overload brings benefits by increasing physical reserve, as we see in the study cited above (Figure 3), the participants carried 14% more weight 10% quicker. The research participants did this additional work with the same perceived exertion, “somewhat hard”, as they reported at baseline. The exercise program done for 3 hours / week had substantial payoffs in making everyday activities easier.
Your house cannot be your exercise program.
Here is how the reasoning goes for someone using the house as an exercise program. “I get winded when I climb from the basement to the main floor, so that is how I will keep up my aerobic fitness. Since my legs get tired, climbing stairs will strengthen my legs. Carrying laundry from the basement to the top-floor is the way to strengthen my upper body.” The act of performing these tasks, draws upon upper and lower body strength to carry laundry and climb stairs. Endurance, as well as, balance and coordination are needed to complete the task and do it safely. The performance of everyday functional tasks, however are intermittent, short (less than 10 minutes) and use only a few muscle groups. Functional tasks cannot truly be designed to systematically increase the load over time to gain aerobic fitness and strength. The very nature of performing everyday function is to limit the discomfort and limit energy expenditure. Such as, accumulating items at the top or bottom of the stairs to limit the number of trips is a common strategy for residents living in of a two or three-story home to minimize trips. A well-rounded exercise program will develop the physical reserve in the areas of fitness needed to perform daily function with the least amount of effort and most efficiently.