In this lesson we'll review physical activity guidelines and talk about the many different ways to meet these guidelines. We'll also talk in more detail about the components of both health and skill-related fitness, and then finally we'll explore the basic principles for designing safe and effective exercise programs that can help individuals achieve the physical activity guidelines and work towards their own physical fitness goals.
Remember that there are multiple different ways to meet the physical activity recommendations for health. First, we can achieve 150 minutes of moderate-intensity aerobic activity. This is something similar to a brisk walk over the course of a week. Alternatively, you could accrue 75 minutes of vigorous-intensity activity, and here this would be something that feels similar to running. Or you could do any combination of those two types of activities, moderate and vigorous. In addition to that aerobic activity, it's recommended that adults get 2 days of muscle-strengthening activities, and those activities should cover all the major muscle groups in the body.
But remember, if you want to get greater health benefits, double your minutes of aerobic physical activity. So you see here in the slide, 300 minutes of moderate-intensity aerobic activity or 150 minutes of vigorous-intensity activity are associated with greater health benefits.
Now take a few minutes to watch this video that clearly illustrates the guidelines and presents just a few ways of how individuals can meet these guidelines.
This next slide is a visual designed to help Americans meet physical activity recommendations, and it's called the MyActivity Pyramid. It's modeled after the original food pyramid, which has now been replaced by a MyPlate, but I think most of us are familiar with the pyramid still. And really, people should work up this pyramid. So you should start at the very bottom, with your lifestyle physical activity, and it kind of is the base of everything you do, and so these are activities that you should do every day, things similar to yard work or household chores, just easy walking, light activities that are incorporated throughout your day. And people should work their way up the pyramid, so if somebody's inactive, they can really start with those lifestyle activities at the bottom, and then work their way up the pyramid. The middle levels of the pyramid highlight the aerobic activity and strengthening and conditioning and flexibility activities that are recommended, and it gives some sample activities that you could participate in, such as brisk walking, jogging, swimming, yoga is given as a flexibility activity, and strength and weight training. At the very top of the pyramid, it is very small, and it represents inactivity, things that we should do very little: sitting behaviors, sedentary behaviors, being on the computer, watching TV, all of these sedentary behaviors are things we want to try to avoid.
This next slide is just a continuation of the MyActivity pyramid. It's really the bottom half of that pyramid that provides a lot more detailed information about the physical activity guidelines. You can see in the bottom right hand of this, the rectangular figure that it gives, tells you that there are guidelines available for other populations beyond adults, so, for example, adults with disabilities, children, women who are pregnant and others. Click on the link at this page and read the physical activity guidelines for children. You should be familiar with the guidelines for children and how they compare to the adult guidelines.
Now we're going to switch gears a little bit and talk about physical fitness, and I want you to remember that this is not the same as physical activity. If you're still unsure about the difference between these two terms, go back, listen to the commentary for Chapter 1 again. But as a review, physical fitness, again, is not a behavior, but rather a set of attributes or characteristics of a person that relates to their ability to perform specific tasks or specific physical activities. Over the next several slides, we'll introduce the two types of fitness, both health and skill-related. We'll talk about the components under each of these types.
The first of five components of health-related fitness is cardiorespiratory endurance. This is simply the ability of your circulatory system—meaning your heart and your blood vessels and your respiratory system, or your lungs—to work together to supply the body with the fuel and the oxygen needed during sustained physical activity, so activity that occurs over a sustained period of time. This also includes the ability of the muscles to take up and use the oxygen that's been delivered during physical activity. Participating in aerobic activities such as biking, swimming, walking, running, are always to improve your cardiorespiratory fitness. These activities increase the demand on your cardiorespiratory system, or your heart and your lungs and your blood vessels, and over time these systems start to adapt to the increased load and become more efficient.
The next two components of health-related fitness are associated with muscular health. The first, muscular strength, is simply the amount of force a muscle can exert during a single, maximal effort. So in the picture here, you see the young woman with a very heavy barbell above her head. She likely just lifted that weight once, it's as much as she could do, and then put it back down. So that would be a great example of muscular strength. Compare that to muscular endurance, which is the ability of a muscle to exert repeated force against a resistance, or to sustain a muscular contraction for a period of time. So examples of muscular endurance might be how many push-ups or sit-ups an individual can complete in a 1-minute period. A great example, I think, of comparing the differences between muscular strength and muscular endurance is if you think about moving into a new apartment or a new house. In one instance you might need to move a very heavy piece of furniture just a very short distance; so let's say you move a big dresser across one of your rooms. But on the other hand, you might be carrying many smaller boxes into your new house or your new apartment over the period of a few hours. In the first case where you move the heavy piece of furniture, that would be a great example of muscular strength, and in the second case, muscular endurance would be needed to carry, repeatedly carry, those smaller loads into the house over a period of a couple hours. Both muscular strength and endurance can be improved through resistance training, and that resistance can really be delivered through many different items. In the example above it was delivered through boxes or furniture, but most often it's delivered through free weights, machines or even a person's own body weight.
The fourth component of health-related fitness is flexibility, or the ability to move your joint through its complete range of motion. This can be improved through stretching exercises where you purposefully work to improve muscle elasticity. Think about all the real-world implications for flexibility, being able to bend, to reach, to twist. All of these things require flexibility. Some of these examples from real-world things that you need flexibility for: reaching for something that's on a high shelf, bending over to tie your shoes, squatting down to plant a garden. All of these things require some level of flexibility. Think of more examples. The final component of health-related fitness is body composition, the ratio of body fat to fat-free mass. Fat-free mass is simply other things in your body such as muscles, bones, organs, water. And remember that this is not a person's weight, but rather the makeup of their body. Regular physical activity and eating a healthy diet are just two of the behaviors that are associated with body composition or how your body's made up. We'll talk a lot more about body composition, obesity and the connection to health in a later chapter.
We'll now move on to the components of skill-related fitness, and here there are six different components, and what you'll see is that we'll talk very briefly about them here, and we're not going to talk too much about the components of skill-related fitness because they're not as closely associated with general and overall health as health-related fitness components were. So we'll talk a lot less over the course of the semester about skill-related components of fitness. The first of these is agility. This is simply the ability to quickly and accurately change the direction of the movement of the entire body in space. So in the picture here you see a baseball player high-stepping through a ladder that's placed on the ground, quickly and efficiently moving his body through this ladder. Another great example is thinking about a running back in football, quickly changing directions during a run, trying to avoid contact with the defender, both great examples of agility. The second component is balance, or the ability to maintain equilibrium while moving or stationary, and here you see a young girl that's balancing on one leg on a balance beam, clearly keeping her balance, keeping her equilibrium while stationary, and it looks like she's about ready to move as well. A great example of where balance is very important in our everyday lives is in older adults who are at risk for falling. Falling can lead to very dangerous complications, especially in people of older age, and so poor balance is really a major risk factor for lots of health complications. So balance is one thing that we may talk about throughout the rest of the semester.
The third component is coordination, using multiple senses to perform activities smoothly and efficiently. The example in the picture is two young ladies jumping rope between two jump ropes. They're combining their sight of the ropes, the sound of the ropes hitting the ground, and other information taken in via their senses, to jump at the appropriate time without hitting those ropes. The fourth component is power, and here we're talking about the application of both speed and strength to produce a muscular movement. One way to train power is by moving a moderate amount of weight very quickly through an athletic movement. So think about athletes, two athletes, passing a medicine ball back and forth very quickly to each other or doing jumps, one athlete doing jumps with that medicine ball. Not as much weight as the athlete could jump with, but a weight that allows them to practice jumping very quickly with that weight. Powerful movements are important for many, many different aspects in athletic performance.
The final two components of skill-related fitness are pictured here on the slide in the picture of the track start, and they're also described here. The first is reaction time: how quickly can someone react to a stimulus? So the example here, when the gun goes off in the track start, how quickly do the runners initiate that first movement? And the second thing that you can see in the picture is speed. These gentlemen in the picture are obviously trying to move quickly from one point to another, which is an example of speed.
Now that we've covered the components of both health and skill-related fitness, we're going to move into talking about some general principles of training, and these principles are just general guidelines that apply to anyone attempting to develop their physical fitness. They're related to the body's response to physical activity and exercise, and regardless of whether someone has been very active throughout their life or whether they've been inactive and are just starting to try to develop their fitness, these principles apply. So the first one of these is overload; here we're talking about stressing the body beyond its normal load or intensity. So, for example, lifting heavier weights than normal or sprinting instead of just running or trying to run instead of walk. All those would be examples of overload. The second principle of training is progression. Think about this as starting slowly and building into an exercise program or training session. So, for one example, think about someone who's been inactive or sedentary for a long time. You wouldn't want to have them go out and run 3 miles for a workout, a very first workout. Instead, you might ask them to start with walking, gradually mix in some running, and then over time progress to running at a faster pace, or increase their speed while they're running. Essentially, this second principle of progression is allowing your body to have a chance to adapt to these new stimuli that you're presenting in the form of exercise or physical activity.
Related to the second principle of progression is the FITT formula: frequency, intensity, time and type. I'll say it one more time: frequency, intensity, time and type. And this is simply a formula that's used as a guideline for creating an exercise program that's both safe and effective for developing physical fitness. Frequency, we're talking about how often you exercise, once a week, twice a week, five times a week. Intensity, we're talking about how hard that exercise session is, how difficult is that session. Time, how long do you exercise, is it 20 minutes, 30 minutes, 60 minutes. And finally the type, what type of exercise do you choose. And all four of these components, all four of these aspects of the FITT formula, are dependent on a couple things. One, the individual's fitness goals, so, for example, the program for someone who wants to enhance their muscular endurance is going to be different than someone who wants to increase their muscular strength. The second thing that it's dependent on is the current level of fitness of the individual, so someone with very high levels of current fitness should be able to handle a more intense or longer exercise session, maybe more sessions per week, compared to someone who's just getting started who would need lower levels of intensity, maybe less frequent, shorter time sessions first and then progress into those more intense and longer sessions.
The next two general principles of training are specificity and reversibility. Specificity is really talking about the idea that fitness gains are specific to the type of activity performed. So if you want improvements in running, you need to run. If you want improvements in muscular strength, you have to perform specific types of resistance training that build that muscular strength. And if you want to get even more detailed, you can think about this as particular activities. So if you're doing bicep curls, you're going to strengthen the muscles of your bicep; it's not going to have any fitness effects on the lower half of your body, for example the quadriceps in your legs. So when you think about developing physical fitness, the activities that you choose must be specific to the type of fitness that you want to develop. Fourth is the principle of reversibility. Here we just mean "Use it or lose it." It's a pretty common phrase that you hear pretty often, and it's the idea that these fitness gains are not permanent, so you must continue to be active to maintain the adaptations that you have made from being physically active and exercising. That doesn't mean that rest is not important; rest is an important part of an effective training plan, but here we're talking about periods of rest that are a week or longer where you might see declines in the adaptations that were made from previous physical activity.
The fifth principle of training is recovery. Rest is an important part of any training plan, just like we just talked about, and rest is in proportion to the intensity and duration of exercise sessions. So the harder and the longer you exercise the more rest that particular body system needs. The sixth and final principle of training is that individual differences matter. At the very extreme, think about the different training needs of a 25-year-old man who's a member of the national soccer team, compared to the training needs of a 75-year-old man who's overweight and has been sedentary for most of his adult life. Clearly, the physical conditions of these two men are very different, and they would need very different training plans. In addition to that, they probably have very different goals. So for example, the 25-year-old man that's a member of the national soccer team might have very specific goals related to soccer, compared to the 75-year-old man who probably has a lot of health-related goals, maybe to reduce his risk of falling, maybe to just improve overall health. But either way, the important point here is that each person, regardless of how different they are or how similar they are, each person has different needs when it comes to developing their own physical fitness.
In addition to the general principles of training, when you're designing an exercise program there are five different things to keep in mind when you're building this program. The first is to make sure that it's safe to begin that exercise program; so this could include talking to your doctor, but it also could include, or start with, taking a questionnaire, such as the PAR-Q,or the Physical Activity Readiness Questionnaire, and there's a copy of this questionnaire, it's ten items, there's a copy posted on Compass. I want you to take a look at it, read over the questions, think about how these questions could relate to whether or not it's safe for you to participate in physical activity. The second is to do some sort of self-assessment of your current fitness level, and this could provide a baseline or starting point for thinking about some of your goals, which leads into the third point here. You need specific goals when we're talking about developing your fitness, and we'll talk a lot more in the future about setting effective goals that are specific and adjustable and timely, but again, we'll talk about this in a future chapter. Fourth, build slowly, and here you can think back to that principle of progression in the FITT formula. You want to start gradually and, in order to maintain consistency and keep up with your physical activity routine, you want to build in slowly.
Finally, choose activities that you enjoy. You'll be much more likely to stick with your program if you pick activities that you enjoy. There are just a few pictured here, hiking, swimming, golfing. There are so many activities to choose from; choosing one that's right for you is really important. You should also keep in mind that you're exercise program should work to improve all of the components of health-related fitness.
